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May 14, 2020

https://www.sciencedaily.com/releases/2020/05/200514115742.htm

The exposome: When our environment drives health and disease

<em>Science</em>

In the two contributions to The exposome is the sum of all the environmental drivers of health and diseases: a combination of external factors such as chemicals contained in the air, water or food, and of internal components produced by our organism in response to various stress factors. This very complex set of elements is continually evolving, and to map it fully is a challenging undertaking. A first paper describes recent progress that will help with this task, such as the development of high-resolution mass spectrometry, a technology that can detect tens of thousands of compounds in biological and environmental samples. Associated with growing databases on all known chemicals and powerful computational tools to analyse large amounts of data, these recent technological advances could revolutionise environmental monitoring.This first paper also highlights that a network approach is needed to take into account the large number of chemical exposures in our daily lives and the complex way they interact with our cells. This is why the second review describes ways to characterise groups of chemicals in diverse samples, from water and soil to biological tissues, and to identify mixtures that pose a combined risk. "Innovative sampling techniques such as hand wipes or silicon bracelets can be used to measure personal exposure," Prof. Schymanski explains. "We also mentioned the importance of non-targeted analyses to identify unknown contaminants and showed the potential of in-vitro bioassays to assess the toxicity of complex mixtures, even if chemical identities remain unknown.""Both papers are a call for a research effort at a scale comparable to what was done for the human genome, to get in-depth knowledge of the cocktail of substances we are exposed to and their intricate interactions with living organisms," Prof. Schymanski points out.There are still many challenges ahead: databases have to be harmonised and made fully accessible, statistical tools need refining in order to account for the constellation of chemicals coming from related sources, and methodologies should be standardised. But despite the difficulties, the perspectives are tremendous.According to the European environment -- state and outlook 2020, we face environmental challenges of unprecedented scale. The number of new chemicals has risen from 20 to 156 million from 2002 and 2019. Pesticides, industrial chemicals and pharmaceuticals can enter the environment and the food chain, possibly causing unwanted effects and disease. Medical research estimates that every year nine million deaths are related to pollution. This highlights the need for research to address the chemical complexity of our world and elucidate the multiple links between environmental quality and health.Just like large scale genomic studies allowed the detection of many genetic variations linked to diseases, the implementation of exposome-wide association studies with hundreds of thousands of participants would help identify the strongest chemical risk factors and understand their impact on individual health. It will enable the establishment of environmental risk scores, which could be used to develop individual prevention and treatment strategies. "On top of providing crucial information for individual patients, research on the exposome will also support the necessary shift in existing policies," Prof. Schymanski says. By helping regulatory bodies to focus on the chemicals with the most adverse effect and elucidating their combined effect, it will help minimise the impact on our health and on the ecosystems we live in. LCSB director Prof. Rudi Balling concludes: "We are proud that with Prof. Schymanski, Luxembourg is now at the forefront of this exciting and significant research field."

Pollution

May 14, 2020

https://www.sciencedaily.com/releases/2020/05/200514115732.htm

How particulate matter arises from pollutant gases

When winter smog takes over Asian mega-cities, more particulate matter is measured in the streets than expected. An international team, including researchers from Goethe University Frankfurt, as well as the universities in Vienna and Innsbruck, has now discovered that nitric acid and ammonia in particular contribute to the formation of additional particulate matter. Nitric acid and ammonia arise in city centres predominantly from car exhaust. Experiments show that the high local concentration of the vapours in narrow and enclosed city streets accelerates the growth of tiny nanoparticles into stabile aerosol particles.

In crowded urban centres, high concentrations of particulate matter cause considerable health effects. Especially in winter months, the situation in many Asian mega-cities is dramatic when smog significantly reduces visibility and breathing becomes difficult.Particulates, with a diameter of less than 2.5 micrometres, mostly form directly through combustion processes, for example in cars or heaters. These are called primary particulates. Particulates also form in the air as secondary particulates, when gases from organic substances, sulphuric acid, nitric acid or ammonia, condense on tiny nanoparticles. These grow into particles that make up a part of particulate matter.Until now, how secondary particulates could be newly formed in the narrow streets of mega-cities was a puzzle. According to calculations, the tiny nanoparticles should accumulate on the abundantly available larger particles rather than forming new particulates.Scientists in the international research project CLOUD have now recreated the conditions that prevail in the streets of mega-cities in a climate chamber at the particle accelerator CERN in Geneva, and reconstructed the formation of secondary particulates: in the narrow and enclosed streets of a city, a local increase of pollutants occurs. The cause of the irregular distribution of the pollutants is due in part to the high pollutant emissions at the street level. Furthermore, it takes a while before the street air mixes with the surrounding air. This leads to the two pollutants ammonia and nitric acid being temporarily concentrated in the street air. As the CLOUD experiments demonstrate, this high concentration creates conditions in which the two pollutants can condense onto nanoparticles: ammonium nitrate forms on condensation cores the size of only a few nanometres, causing these particles to grow rapidly."We have observed that these nanoparticles grow rapidly within just a few minutes. Some of them grow one hundred times more quickly than we had previously ever seen with other pollutants, such as sulphuric acid," explains climate researcher Professor Joachim Curtius from Goethe University Frankfurt. "In crowded urban centres, the process we observed therefore makes an important contribution to the formation of particulate matter in winter smog -- because this process only takes place at temperatures below about 5 degrees Celsius." The aerosol physicist Paul Winkler from the University of Vienna adds: "When conditions are warmer, the particles are too volatile to contribute to growth."The formation of aerosol particles from ammonia and nitric acid probably takes place not only in cities and crowded areas, but on occasion also in higher atmospheric altitudes. Ammonia, which is primarily emitted from animal husbandry and other agriculture, arrives in the upper troposphere from air parcels rising from close to the ground by deep convection, and lightning creates nitric acid out of nitrogen in the air. "At the prevailing low temperatures there, new ammonium nitrate particles are formed which as condensation seeds play a role in cloud formation," explains ion physicist Armin Hansel from the University of Innsbruck, pointing out the relevance of the research findings for climate.The experiment CLOUD (Cosmics Leaving OUtdoor Droplets) at CERN studies how new aerosol particles are formed in the atmosphere out of precursor gases and continue to grow into condensation seeds. CLOUD thereby provides fundamental understanding on the formation of clouds and particulate matter. CLOUD is carried out by an international consortium consisting of 21 institutions. The CLOUD measuring chamber was developed with CERN know-how and achieves very precisely defined measuring conditions. CLOUD experiments use a variety of different measuring instruments to characterise the physical and chemical conditions of the atmosphere consisting of particles and gases. In the CLOUD project, the team led by Joachim Curtius from the Institute for Atmosphere and Environment at Goethe University Frankfurt develops and operates two mass spectrometers to detect trace gases such as ammonia and sulphuric acid even at the smallest concentrations as part of projects funded by the BMBF and the EU. At the Faculty of Physics at the University of Vienna, the team led by Paul Winkler is developing a new particle measuring device as part of an ERC project. The device will enable the quantitative investigation of aerosol dynamics specifically in the relevant size range of 1 to 10 nanometres. Armin Hansel from the Institute for Ion Physics and Applied Physics at the University of Innsbruck developed a new measuring procedure (PTR3-TOF-MS) to enable an even more sensitive analysis of trace gases in the CLOUD experiment with his research team as part of an FFG project.

Pollution

May 13, 2020

https://www.sciencedaily.com/releases/2020/05/200513111434.htm

New, rapid mechanism for atmospheric particle formation

Carnegie Mellon University researchers working with an international team of scientists have discovered a previously unknown mechanism that allows atmospheric particles to very rapidly form under certain conditions. The research, which was published in the journal

"The only real uncertainties in our understanding of climate in the atmosphere have to do with fine particles and clouds, how these have changed over time and how they will respond to climate change," said Neil Donahue, Thomas Lord University Professor of Chemistry and a professor in the departments of Chemical Engineering, and Engineering and Public Policy.The number of particles in the atmosphere at any given time can have major effects locally and globally, including contributing to unhealthy smog in cities and influencing the Earth's climate. However, particles need to reach a certain size -- around 100 nanometers in diameter -- to contribute to those effects, Donahue noted.If particles don't reach that size, they quickly get subsumed into other, larger particles. This means that one would expect few new particles to be created in polluted urban environments where the air is already full of larger particles that could gobble up small, new particles. Yet new particle formation is relatively common in those environments, as plainly seen when haze reforms rapidly after rainfall in cities around the world.Donahue thinks the answer to that mystery may lie in this new research. "We found a new way for tiny nucleated particles in the atmosphere to grow up quickly to become large enough to affect climate and health," he said.Donahue's lab group has long been part of the CLOUD experiment, an international collaboration of scientists that use a special chamber at CERN in Switzerland to study how cosmic rays affect the formation of particles and clouds in the atmosphere. The chamber allows researchers to precisely mix vaporous compounds and observe how particles form and grow from them.In this study, designed by Carnegie Mellon chemistry doctoral candidate Mingyi Wang, the CLOUD team condensed nitric acid and ammonia vapors across a wide range of temperatures and found that the resulting new particles can grow 10 to 100 times faster than previously observed, allowing them to reach sizes large enough to avoid being consumed by other particles. The compound formed from those two vapors, ammonium nitrate (a common fertilizer), was previously known to be a contributor to atmospheric pollution within larger particles, but its role in helping tiny particles grow was not known."This may help explain how nucleated particles grow up in polluted urban conditions in mega-cities, which has been a big puzzle, as well as how they form in the upper parts of the atmosphere, where they can have a strong climate effect," Donahue explained. The team is now working to study how this mechanism plays out in Earth's upper atmosphere.For Wang, who served as co-leader of the study, this research has roots in his keen desire to understand air pollution. After an undergraduate research project where he got to sample and analyze PM2.5, Wang decided to continue in this field of research to better explore how these small particles can have such a big impact on the planet and how that impact could be remedied."I realized that those atmospheric particulate matters have never been a simple air quality problem that only Asia needs to deal with," Wang said. "Rather, they are a global challenge due to their health and climate effects."

Pollution

May 13, 2020

https://www.sciencedaily.com/releases/2020/05/200513111415.htm

Cold War nuke tests changed rainfall

Nuclear bomb tests during the Cold War may have changed rainfall patterns thousands of miles from the detonation sites, new research has revealed.

Scientists at the University of Reading have researched how the electric charge released by radiation from the test detonations, carried out predominantly by the US and Soviet Union in the 1950s and 1960s, affected rainclouds at the time.The study, published in Professor Giles Harrison, lead author and Professor of Atmospheric Physics at the University of Reading, said: "By studying the radioactivity released from Cold War weapons tests, scientists at the time learnt about atmospheric circulation patterns. We have now reused this data to examine the effect on rainfall."The politically charged atmosphere of the Cold War led to a nuclear arms race and worldwide anxiety. Decades later, that global cloud has yielded a silver lining, in giving us a unique way to study how electric charge affects rain."It has long been thought that electric charge modifies how water droplets in clouds collide and combine, potentially affecting the size of droplets and influencing rainfall, but this is difficult to observe in the atmosphere. By combining the bomb test data with weather records, the scientists were able to retrospectively investigate this.Through learning more about how charge affects non-thunderstorm clouds, it is thought that scientists will now have a better understanding of important weather processes.The race to develop nuclear weapons was a key feature of the Cold War, as the world's superpowers sought to demonstrate their military capabilities during heightened tensions following the Second World War.Although detonations were carried out in remote parts of the world, such as the Nevada Desert in the US, and on Pacific and Arctic islands, radioactive pollution spread widely throughout the atmosphere. Radioactivity ionises the air, releasing electric charge.The researchers, from the Universities of Reading, Bath and Bristol, studied records from well-equipped Met Office research weather stations at Kew near London and Lerwick in the Shetland Isles.Located 300 miles north west of Scotland, the Shetland site was relatively unaffected by other sources of anthropogenic pollution. This made it well suited as a test site to observe rainfall effects which, although likely to have occurred elsewhere too, would be much more difficult to detect.Atmospheric electricity is most easily measured on fine days, so the Kew measurements were used to identify nearly 150 days where there was high or low charge generation over the UK while it was cloudy in Lerwick. The Shetland rainfall on these days showed differences which vanished after the major radioactivity episode was over.The findings may be helpful for cloud-related geoengineering research, which is exploring how electric charge could influence rain, relieve droughts or prevent floods, without the use of chemicals.Professor Harrison is leading a project investigating electrical effects on dusts and clouds in the United Arab Emirates, as part of their national programme in Rain Enhancement Science. These new findings will help to show the typical charges possible in natural non-thunderstorm clouds.

Pollution

May 11, 2020

https://www.sciencedaily.com/releases/2020/05/200511112557.htm

Water loss in northern peatlands threatens to intensify fires, global warming

A group of 59 international scientists, led by researchers at Canada's McMaster University, has uncovered new information about the distinct effects of climate change on boreal forests and peatlands, which threaten to worsen wildfires and accelerate global warming.

Manuel Helbig and Mike Waddington from McMaster's School of Geography and Earth Sciences gathered observational data from collaborators in countries across the boreal biome. Their study of how ecosystems lose water to the atmosphere appears today in the journal The unprecedented detail of their work has highlighted dramatic differences in the ways forests and peatlands regulate water loss to the atmosphere in a warming climate, and how those differences could in turn accelerate the pace of warming.Most current global climate models assume the biome is all forest, an omission that could seriously compromise their projections, Helbig says."We need to account for the specific behavior of peatlands if we want to understand the boreal climate, precipitation, water availability and the whole carbon cycle," he says."Peatlands are so important for storing carbon, and they are so vulnerable."Until now, Helbig says, it had not been possible to capture such a comprehensive view of these water-cycle dynamics, but with the support of the Global Water Futures Initiative and participation from so many research partners in Canada, Russia, the US, Germany and Scandinavia, new understanding is emerging.As the climate warms, air gets drier and can take up more water. In response to the drying of the air, forest ecosystems -- which make up most of the world's natural boreal regions -- retain more water. Their trees, shrubs and grasses are vascular plants that typically take up carbon dioxide and release water and oxygen through microscopic pores in their leaves. In warmer, dryer weather, though, those pores close, slowing the exchange to conserve water.Together with lakes, the spongy bogs and fens called peatlands make up the remainder of the boreal landscape. Peatlands store vast amounts of water and carbon in layers of living and dead moss. They serve as natural firebreaks between sections of forest, as long as they remain wet.Peatland mosses are not vascular plants, so as warming continues, they are more prone to drying out. Unlike forests, they have no active mechanism to protect themselves from losing water to the atmosphere. Dehydration exposes their dense carbon stores to accelerated decomposition, and turns them from firebreaks into fire propagators, as shown in previous research from Waddington's ecohydrology lab.Drier peatlands mean bigger, more intense fires that can release vast amounts of carbon into the atmosphere, accelerating global warming, Helbig says."It's crucial to consider the accelerated water loss of peatlands in a warming climate as we project what will happen to the boreal landscape in the next 100 to 200 years," he says.

Pollution

May 8, 2020

https://www.sciencedaily.com/releases/2020/05/200508112906.htm

Human-driven pollution alters the environment even underground

The Monte Conca cave system on the island of Sicily is a vast system of springs and pools, sitting below a nature preserve. It might be presumed to be one of the few places untouched by human-driven pollution.

But new research published by a USF microbiology and geoscience team has found that even below ground, the microbial communities in the pools of water in the Monte Conca cave show signs of being altered by pollution from above.Publishing in the prestigious journal, PLoS One, the team found that water flowing through the vast cave system produced changes in the microbial communities between the wet and dry seasons, with the microbial communities differing in bacterial composition and ecological functions. The study suggests that as surface water flows through agricultural and urban areas, it collects bacterial contaminants before entering cave systems.The purpose of the study was to determine the impact surface runoff has on cave microbial communities using the Monte Conca spring pool as a model. The long-term impacts of these surface-derived bacterial contaminants or their impact on groundwater sources is currently not well known, said lead author Dr. Madison Davis of USF's Department of Cell Biology, Microbiology and Molecular Biology.The project was led by USF Professor James Garey of the Department of Cell Biology, Microbiology and Molecular Biology, and Professor Bogdan P. Onac of USF's School of Geosciences. USF graduate and undergraduate students Madison C. Davis, Melvin D. Baker IV, Christiana K. S. Mayne, Chelsea M. Dinon and Christina J. Moss are co-authors on the paper.The group collaborated with Italian colleagues Maria A. Messina, Giuseppe Nicolosi and Salvatore Petralia of Centro Speleologico Etneoa.The scientists found that the dry season microbial community was dominated by sulfur-oxidizing bacteria because of their ability to utilize oxygen from the cave and hydrogen sulfide from the spring pool. After a heavy rainfall, the sulfur-oxidizing community was displaced by surface-derived bacteria that were primarily identified as human contaminants, including Escherichia coli and other fecal bacteria.Caves like Monte Conca -- which is Sicily's longest and deepest gypsum karst system and was formed by sulfuric acid dissolution -- have been identified worldwide. To carry out their work, researchers traveled into the cave system to retrieve samples in four missions spanning 2015 and 2016.Sulfur oxidizers comprised more than 90 percent of the microbial community during the dry season and were replaced by potential human-influenced contaminants such as Escherichia and Lysinibacillus species after heavy rains, the researchers said. One sampling appeared to show a transition between the wet and dry seasons when potential man-made contaminants, sulfur-oxidizing bacteria and nitrogen-fixing bacteria all were present within the spring pool.The study demonstrates the impact of surface runoff on the microbial community structure and function of endemic cave communities, the researchers said.

Pollution

May 7, 2020

https://www.sciencedaily.com/releases/2020/05/200507131313.htm

A radar for plastic: High-resolution map of 1 kilometer grids to track plastic emissions in seas

Plastic may be an indispensable part of our daily lives, but its robustness and abundance have led to its overuse, putting a huge burden on the environment. Large emissions of plastic waste result in its accumulation in water bodies: in fact, recent studies have estimated about 0.27 million tons of plastic floating in the world's oceans. Because plastic does not decompose in water, it is a serious hazard for the marine life. Thus, to prevent plastic pollution, it is crucial to understand exactly how plastic is emitted into the oceans. Previous studies have tried to analyze plastic emissions, but they had some limitations: they focused on mostly mismanaged plastic waste and not how these plastic emissions actually originate.

To this end, a group of scientists at the Tokyo University of Science, led by Prof Yasuo Nihei, developed a new method to combat plastic emissions. In a study published in To begin with, the scientists focused on the different types of plastics: microplastic (MicP), which is less than 5 mm in size, and macroplastic (MacP), which is greater than 5 mm. They understood that controlling MicP was crucial because -- owing to its small size -- it is particularly hard to recover once it enters the ocean. Moreover, it can easily be ingested by marine organisms, which can negatively affect ecosystems worldwide. To avoid the emission of MicP in water bodies, it was important to find out exactly where these emissions were coming from.The scientists followed a three-step process to map plastic emissions. First, they measured MicP concentration across 70 rivers and 90 sites in Japan and examined the relation between MicP concentration and land characteristics. They collected the ratio of MacP/MicP concentrations to evaluate the MacP concentration from the MicP concentration. Next, to obtain outflow discharge at 1 km grids, they performed a "water balance analysis" in which they measured precipitation of water, distributed into three categories: evaporation, surface runoff, and underground infiltration. Finally, they calculate total plastic emission, which is the product of MicP and MacP concentrations and outflow discharge. Their findings revealed that MicP concentrations and basin characteristics were significantly correlated, meaning that the physical features of water bodies dictate the amount of plastic waste accumulated. Not just this, their analysis helped the scientists to estimate the annual plastic emission in Japan, which ranged from 210 to 4,776 tons/year of total plastic.The scientists then evaluated a high-resolution map of plastic emission over 1 km grids across Japan. They identified the critical areas where plastic emissions were the highest. Their analysis showed that these emissions were high in rivers near urbanized areas, with a high population density. Among these, cities like Tokyo, Nagoya, and Osaka were found to be hotspots for plastic emissions. Thus, this method was useful in understanding exactly where strict countermeasures should be enforced.Unlike previous studies, this study does not assume that the plastic waste is only proportional to mismanaged plastic waste but, in fact, takes into account the origin of plastic emissions. This makes it easier to implement measures and curb plastic emissions in specific areas. Prof Nihei concludes, "Our findings provide new insights that may be used to draft countermeasures against plastic emissions, thereby reducing outflow of marine pollutants from Japan. We also introduce a new method that can be used to evaluate plastic inputs in other regions of the world."

Pollution

May 6, 2020

https://www.sciencedaily.com/releases/2020/05/200506162159.htm

Cold air with water vapor rises: What that means for earth's climate

Conventional knowledge has it that warm air rises while cold air sinks. But a study from the University of California, Davis, found that in the tropical atmosphere, cold air rises due to an overlooked effect -- the lightness of water vapor. This effect helps to stabilize tropical climates and buffer some of the impacts of a warming climate.

The study, published today in the journal "It's well-known that water vapor is an important greenhouse gas that warms the planet," said senior author Da Yang, an assistant professor of atmospheric sciences at UC Davis and a joint faculty scientist with Lawrence Berkeley National Laboratory. "But on the other hand, water vapor has a buoyancy effect which helps release the heat of the atmosphere to space and reduce the degree of warming. Without this lightness of water vapor, the climate warming would be even worse."Humid air is lighter than dry air under the same temperature and pressure conditions. This is called the vapor buoyancy effect. This study discovered this effect allows cold, humid air to rise, forming clouds and thunderstorms in Earth's tropics. Meanwhile, warm, dry air sinks in clear skies. Earth's atmosphere then emits more energy to space than it otherwise would without vapor buoyancy.The study found that the lightness of water vapor increases Earth's thermal emission by about 1-3 watts per square meter over the tropics. That value compares with the amount of energy captured by doubling carbon dioxide in the atmosphere. The authors' calculations further suggest that the radiative effects of vapor buoyancy increase exponentially with climate warming.A better understanding of the vapor buoyancy effect and its stabilizing role in the tropics can also improve cloud and thunderstorm simulations, as well as climate models, the study said."Now that we understand how the lightness of water regulates tropical climate, we plan to study whether global climate models accurately represent this effect," said the study's lead author, Seth Seidel, a graduate student researcher at UC Davis.The study was funded by the David and Lucille Packard Foundation and the U.S. Department of Energy.

Pollution

May 5, 2020

https://www.sciencedaily.com/releases/2020/05/200505072200.htm

Saving energy and lives: How a solar chimney can boost fire safety

A must-have in green building design, solar chimneys can slash energy costs up to 50%. Now research reveals they could also help save lives in a building fire.

In a world-first, researchers designed a solar chimney optimised for both energy saving and fire safety, as part of the sustainable features of a new building in Melbourne, Australia.Modelling shows the specially-designed solar chimney radically increases the amount of time people have to escape the building during a fire -- extending the safe evacuation time from about two minutes to over 14 minutes.A solar chimney is a passive solar heating and cooling system that harnesses natural ventilation to regulate the temperature of a building.With an estimated 19% of the world's energy resources going to heating, ventilating and cooling buildings, integrating solar chimneys into new builds and retrofitting to existing structures offers great potential for reducing this massive environmental cost.In the new project, a collaboration between RMIT University and the City of Kingston, researchers designed a solar chimney to maximise its efficiency for both ventilating fresh air and sucking smoke out of a building in case of fire.Researcher Dr Long Shi said solar chimneys have well established environmental credentials, but their potential for improving fire safety had not been explored."In an emergency situation where every second counts, giving people more time to escape safely is critical," Shi said."Our research demonstrates that solar chimneys offer powerful benefits for both people's safety and the environment."Delivering on two important functions could boosts the already strong cost-effectiveness of this sustainable technology."We hope our findings will inspire more investment and development of solar chimneys in Australia, and around the world."Kingston Mayor Georgina Oxley said Council was excited to be a part of the groundbreaking project."Creating new and innovative ways of reducing energy consumption in our building design is something that is a priority for Council," Oxley said."The solar-chimney that has been installed at the new state-of-the-art Mentone Reserve Pavilion not only allows us to harness clean green energy to heat and cool the building, helping Council achieve its environmental goals, but it also has the potential to save lives in the event of a fire. This is a truly remarkable design."While calculations around the 6-fold increase in safe evacuation time were specific to the new building, previous research by the team from RMIT's School of Engineering has confirmed solar chimneys can successfully achieve both functions -- ventilation and smoke exhaustion.The passive design approach behind solar chimneys operates on the well-known principle that hot air always rises.Modern solar chimneys usually feature a wall of glass next to a wall that is painted black, to maximise the absorption of solar radiation. Vents at the top and bottom control the airflow in and out of the chimney for heating or cooling.As the sun warms the chimney, this heats the air inside it.The hot air rises and is vented out of the top of the chimney, which draws more air in at the bottom, driving ventilation through a building to naturally cool it down.When it's cold outside, the chimney can be closed, to direct the absorbed heat back into the building and keep it warm.It's an ingeniously simple concept that is relatively cheap to retrofit and adds almost no extra cost to a new build, but can drive energy consumption down.During a fire, the same principle -- hot air rises -- enables the solar chimney to suck smoke out of the building.Less smoke means better visibility, lower temperatures and reduced carbon monoxide -- all of which contribute to increasing the amount of time people have to safely evacuate.To understand exactly how much evacuation time a solar chimney could deliver for a specific building, you need to model for that exact design, Shi said."This will differ from building to building, but we know that any extra time is precious and improves fire safety, which could ultimately help to save lives," he said.The new research offers a technical guide for optimising the design and engineering of solar chimneys in real buildings, to expand their application across the two functions.

Pollution

May 4, 2020

https://www.sciencedaily.com/releases/2020/05/200504155207.htm

Climate change has been influencing where tropical cyclones rage

While the global average number of tropical cyclones each year has not budged from 86 over the last four decades, climate change has been influencing the locations of where these deadly storms occur, according to new NOAA-led research published in

New research indicates that the number of tropical cyclones has been rising since 1980 in the North Atlantic and Central Pacific, while storms have been declining in the western Pacific and in the southern Indian Ocean."We show for the first time that this observed geographic pattern cannot be explained only by natural variability," said Hiroyuki Murakami, a climate researcher at NOAA's Geophysical Fluid Dynamics Laboratory and lead author.Murakami used climate models to determine that greenhouse gases, humanmade aerosols including particulate pollution, and volcanic eruptions were influencing where tropical cyclones were hitting.Greenhouse gases are warming the upper atmosphere and the ocean. This combines to create a more stable atmosphere with less chance that convection of air currents will help spawn and build up tropical cyclones.Particulate pollution and other aerosols help create clouds and reflect sunlight away from the earth, causing cooling, Murakami said. The decline in particulate pollution due to pollution control measures may increase the warming of the ocean by allowing more sunlight to be absorbed by the ocean.Diminishing humanmade aerosols is one of the reasons for the active tropical cyclones in the North Atlantic over the last 40 years, Murakami said. However, toward the end of this century, tropical cyclones in the North Atlantic are projected to decrease due to the "calming" effect of greenhouse gases.Volcanic eruptions have also altered the location of where tropical cyclones have occurred, according to the research. For example, the major eruptions in El Chichón in Mexico in 1982 and Pinatubo in the Philippines in 1991 caused the atmosphere of the northern hemisphere to cool, which shifted tropical cyclone activity southward for a few years. Ocean warming has resumed since 2000, leading to increased tropical cyclone activity in the northern hemisphere.Climate models project decreases in tropical cyclones toward the end of the 21st century from the annual average of 86 to about 69 worldwide, according to the new study. Declines are projected in most regions except in the Central Pacific Ocean, including Hawaii, where tropical cyclone activity is expected to increase.Despite a projected decline in tropical cyclones by 2100, many of these cyclones will be significantly more severe. Why? Rising sea surface temperatures fuel the intensity and destructiveness of tropical storms."We hope this research provides information to help decision-makers understand the forces driving tropical cyclone patterns and make plans accordingly to protect lives and infrastructure," Murakami said.

Pollution

May 4, 2020

https://www.sciencedaily.com/releases/2020/05/200504101626.htm

Pacific oysters may not contain as many microplastics as previously thought

Plastic pollution is an increasingly present threat to marine life and one which can potentially impact your dinner table.

Oysters, and other economically valuable shellfish, filter their food from the water where they may also inadvertently capture tiny microplastics. The ingestion and accumulation of these microplastics can have detrimental effects on their health and may be passed to other animals, including humans, through the food chain.In a recent interdisciplinary study, University of Washington researchers at the School of Aquatic and Fishery Sciences, Department of Chemistry and Department of Materials Science and Engineering used advanced methodologies to accurately identify and catalog microplastics in Pacific oysters from the Salish Sea. They have discovered that the abundance of tiny microplastic contaminants in these oysters is much lower than previously thought. The findings were published in January in the journal "Until now, not a lot of chemical analysis has been done on microplastics in oysters," said co-author Samantha Phan, a UW doctoral student in chemistry. "The microplastics that chemists have looked at in previous studies are slightly bigger and easy to visually recognize, but with oysters, the microplastics are much smaller and harder to identify."In their study, the team sampled wild Pacific oysters harvested from Washington's state parks throughout the Salish Sea. Using standard processing methods, the oysters' tissue is dissolved and the remaining solution is passed through a filter. The filter collects all of the possible microplastic particles."Observation of filters is the method researchers have typically used, so if we had stopped there, we would have thought all the oysters had microplastics because small particles were present in most of the filters," said lead author Julieta Martinelli, a UW postdoctoral researcher at the School of Aquatic and Fishery Sciences.Martinelli's initial observations under a dissecting microscope revealed what were thought to be high numbers of microplastics left behind in the testing filters, but when Phan further analyzed those filters with three advanced chemical identification techniques, they realized that most of what was left in the filters was not actually plastic."When we're characterizing plastics, or any polymers in chemistry in general, we have to use multiple techniques, and not every technique will give you a full picture. It's half a picture or just part of the picture," said Phan. "When you put all those pictures and characterizations together, you can have a more complete understanding of what the composition or identities of these particles are."During their analyses, the team realized that many of the particles were, in fact, shell fragments, minerals, salts and even fibers from the testing filters themselves. In the end, they found that only about 2% of the particles distilled from the oysters could be confirmed as plastics."Most people so far have not used the combination of techniques or instruments that we used," said Martinelli. "It's really easy to stop at the first part and say, 'Oh, there's a lot of particles here. They look like plastic. They must be plastic.' But when you actually go deeper into the chemical composition, they might not be."The number of plastic particles that the team found was relatively low compared to the total number of particles analyzed; however, they stress that while it appears Pacific oysters are not accumulating large amounts of plastic, they could not identify 40% of the particles observed due to technical limitations. The researchers also acknowledge that while using a combination of instruments is the most complete way to analyze these particles, access to the equipment, elevated costs and the extremely time-consuming nature of the work are limiting factors for widespread use.As suspension feeders, oysters pull in water and the particles present in it when they inhale. Particles are then sorted in and out of the animal through their gills. Previous experiments have shown that when oysters are given microfibers or microbeads, they expel the majority of them either immediately or after a few hours. The hypothesis is that oysters' gill anatomy and physiology might be the reason why the team did not see large amounts of plastic accumulation in their samples."A lot of this has to do with how the oysters process water through their gills and how they get rid of particles," said Martinelli. "It doesn't mean microplastics are not in the water, it means that the animals are better at expelling them."In agreement with this, it has been suggested that suspension feeding bivalves like oysters might not be good indicators of pollution in estuaries because they naturally expel microplastics instead of ingesting them, which is good news for consumers that like eating oysters.

Pollution

April 29, 2020

https://www.sciencedaily.com/releases/2020/04/200429105830.htm

Long-term consequences of coastal development as bad as an oil spill on coral reefs

The near-shore habitats of Bahia Las Minas in the central Caribbean coast of Panama became heavily contaminated after a refinery accident in 1986. Over the next five years, there was a significant decline in the numbers and diversity of corals. Thirty years later, researchers from the Smithsonian Tropical Research Institute (STRI) and collaborating institutions report on the long-term changes of the oil spill on coral communities. Their findings were published in the journal

Oil pollution is known to cause lethal and sublethal responses on coral communities in the short-term, but its long-term effects have not been widely studied. The Bahia Las Minas oil spill, which contaminated about 40 square kilometers (about 15 square miles) near the Smithsonian's Galeta Point Marine Laboratory in Colon and became the largest recorded near coastal habitats in Panama, served as an opportunity to understand how coral reefs in tropical ecosystems recover from acute contamination over time."Monitoring these coral reefs was complex, exhausting and intense due to the large spatial scale of the project," said Héctor M. Guzmán, STRI marine ecologist. "Originally, we compared the contaminated refinery area with uncontaminated reef systems about 50 kilometers to the east between Portobelo and Isla Grande."After the first five years, the team found that the abundance and diversity of most hard corals (Scleractinia), some branching and massive corals, and fire corals (Millepora) had decreased in the affected area. Other organisms, such as crustose coralline algae, an encrusting stony kind of seaweed that grows in the gaps between coral reefs, and Agaricia tenuifolia, a lettuce type of hard coral, had increased."Oil residues from the spill on the sediment surface were quickly degraded through natural weathering processes," said Stefanie Kaiser, a marine biologist at the University of Lodz. "However, a large amount of oil has been trapped in deeper layers where weathering processes are strongly hampered. The chronic effects of this reoccurring oil leaking from sediments could have been by far worse for affected coral communities than the acute effects of the spill."A similar phenomenon occurred after the Deepwater Horizon oil spill in the Gulf of Mexico in April 2010, the largest in United States history. Ten years later, high levels of oil pollution continue to be found in organisms inhabiting the seafloor. However, as sea currents stir up these polluted sediments, they also contaminate species living at shallower waters.Thirty years after the Bahia Las Minas spill, there were no longer any significant differences between the area near the oil refinery and the area the original team used for comparison. Since the mid-1990s, this area was affected by coastal development and deforestation. In both areas, the number and diversity of species had declined and the number of juvenile colonies was low. That is, the younger corals and associated organisms were not enough to regenerate healthy coral communities.The similarities between both areas had more to do with the sustained deterioration of the Portobelo-Isla Grande coastal area than with an improvement in the conditions of Bahia Las Minas after the oil spill. These effects were related to coastal development and other human-related impacts on the reefs, such as rising sea temperatures, coral diseases, overfishing and aquatic pollution and sedimentation."The initial impact on the reef community was clear and somewhat predictable, a gradual recovery and an increase in the more resistant coral species," Guzmán said. "Nevertheless, we did not expect to see a similar response in our 'control' reefs where the long-term impact of coastal development was equal to or greater than the initial oil spill."Although the long-term consequences of oil pollution on reef communities could not be determined, scientists worry about the way these external factors are contributing to the deterioration of marine ecosystems in previously healthy areas and preventing recovery in areas affected by oil contamination."The coral reefs along Panama's central Caribbean coast are practically doomed by coastal development," Guzmán said. "If unplanned development continues on the rise, they may continue to survive, but without any substantial recovery."

Pollution

April 29, 2020

https://www.sciencedaily.com/releases/2020/04/200429092325.htm

Upcycling spongy plastic foams from shoes, mattresses and insulation

Researchers have developed a new method for upcycling polyurethane foams, the spongy material found in mattresses, insulation, furniture cushions and shoes.

This process, developed by researchers at Northwestern University and the University of Minnesota, first involves mixing postconsumer polyurethane foam waste with a catalyst solution that allows the foam to become malleable. Next, the method uses a "twin-screw" extrusion process that both removes air from the foam to create a new material in the shape of a hard, durable plastic or soft, flexible film as well as remolds the material.This allows foam waste to be processed into higher quality rubbers and hard plastics for use in shoe cushioning, watch wristbands, hard durable wheels (for shopping carts and skateboards) and in automotive applications, such as bumpers."Polyurethane foam waste has historically been landfilled and burned or downcycled for use in carpeting," said Northwestern's William Dichtel, who co-led the research. "Our latest work effectively removes air from polyurethane foams and remolds them into any shape. This could pave the way for industry to begin recycling polyurethane foam waste for many relevant applications."The research will be published April 29 in the journal Dichtel is the Robert L. Letsinger Professor of Chemistry in Northwestern's Weinberg College of Arts and Sciences. He co-led the research with Christopher Ellison, an associate professor of chemical engineering and materials science at the University of Minnesota.Often made from toxic building blocks, polyurethane foam is a stubborn material that frequently ends up at the bottom of landfills. While other types of plastics can be melted down and recycled, polyurethane foam's chemical bonds are so strong that it does not melt -- even in extreme heat. At best, people can shred it into synthetic fibers, which can then be downcycled into carpet and brushes.Other upcycling efforts have compressed the foam to remove its air, but this resulted in cracked or unevenly blended materials. Dichtel and Ellison's approach uses two intermeshing, co-rotating screws to simultaneously mix and remold the foam. This improved mixing and air removal.

Pollution

April 28, 2020

https://www.sciencedaily.com/releases/2020/04/200428112544.htm

Plastic pollution reaching the Antarctic

Food wrapping, fishing gear and plastic waste continue to reach the Antarctic. Two new studies into how plastic debris is reaching sub-Antarctic islands are published this month (April 2020) in the journal

New findings include analyses of some of the longest continuous datasets in the world on plastics ingested by seabirds and washed up on beaches, and insights into where this plastic originates. They also highlight the ongoing prevalence of plastic in the Polar Regions, its impact on the environment and the animals that inhabit these remote areas.Scientists from British Antarctic Survey (BAS) have systematically collected marine debris washed up on the beaches of Bird Island (South Georgia) and Signy Island (South Orkneys) over three decades. Their findings reveal an increase in the amount of debris collected. Over 10,000 items were recovered, the majority of which was plastic.Lead author Dr Claire Waluda, a marine ecologist at BAS says:"While we found an increase in the quantity of beached plastic debris, recent surveys have shown increasing numbers of smaller pieces. This might be due to the breakdown of larger pieces of plastic which have been in the Southern Ocean for a long time.""It's not all bad news. With the amount of plastic recovered on beaches peaking in the 1990s, our study suggests that the measures to restrict the amount of debris entering the Southern Ocean have been successful, at least in part. But more still needs to be done. By putting our data into oceanographic models we will learn more about the sources and sinks of plastic waste and how it is transported into and around the Southern Ocean."A second BAS-led study used seabirds as sentinels of plastic pollution, due to their natural tendency to consume indigestible items -- such as plastic -- which they mistake for natural prey. Over 30 years, researchers looked at the variation in plastic ingestion by three species of albatrosses, including the wandering albatross, and giant petrels on Bird Island.Researchers categorised debris -- including type, size, colour and origin. They found substantial differences in the characteristics of the marine debris associated with South Georgia's seabirds.For example, items ingested by wandering albatrosses and giant petrels were primarily food-related wrapping that had been packaged in South America. These species typically scavenge behind vessels so the debris is highly likely to be waste items that have been discarded or lost overboard.Lead author and seabird ecologist at BAS, Professor Richard Phillips, says:"Our study adds to a growing body of evidence that fishing and other vessels make a major contribution to plastic pollution. It's clear that marine plastics are a threat to seabirds and other wildlife and more needs to be done to improve waste-management practices and compliance monitoring both on land and on vessels in the South Atlantic.""There is some good news, we found that black-browed albatrosses typically ingested relatively low levels of debris, suggesting that plastic pollution in the Antarctic waters where they feed remains relatively low."Long-term monitoring on the islands continues whilst the rest of the world is in lockdown.Bird Island lies off the north-west tip of South Georgia and is one of the richest wildlife sites in the world. It is around 1000km south-east of the Falkland Islands and is only accessible by ship. Temperatures there vary from -10 to 10?C. Bird Island Research Station is an important centre for research into seabird and seal biology. The station operates year-round.Signy Island is one of the remote South Orkney Islands, more than 1300km from the Falkland Islands. Around half the island is covered by a permanent ice cap; the lowest recorded temperature is -39.3°C. Signy Research Station is only occupied during the Antarctic summer. Research here focuses on bird populations and terrestrial ecologyFour species of albatrosses breed at South Georgia -- wandering albatross, grey-headed albatross, black-browed albatross and light-mantled albatross. Albatrosses fly huge distances when foraging for food, even during breeding, with the foraging ranges of most species covering thousands of square kilometres of ocean. The wandering albatross is the world's largest seabird with a wingspan of over 3m. They can live over 60 years and range from sub-tropical to Antarctic waters on trips covering up to 10,000km in 10-20 days. Fishing fleets kill more than 100,000 albatrosses every yearGiant petrels also breed in Antarctica, feeding mostly on carrion, fish, squid and crustaceans. They lay a single egg, are generally colonial and both parents share incubation and chick-rearing duties. Like albatrosses, petrels have low reproductive rates and thereby low potential for population recovery, making them susceptible to environmental change.

Pollution

April 28, 2020

https://www.sciencedaily.com/releases/2020/04/200428112531.htm

Simulating borehole ballooning helps ensure safe drilling of deep-water oil, gas

A device which simulates borehole ballooning, a detrimental side effect of deep-water drilling operations, is expected to ensure safe and efficient operations. If not prevented, borehole ballooning can lead to irreversible damage and serious drilling accidents, which can result in reservoir pollution and huge economic loss.

In a recent issue of the "In order to promote the development of deep-water drilling technology and ensure the safe and efficient exploitation of deep-water oil and gas, we have conducted research on the problems encountered in deep-water drilling processes, and the borehole ballooning is one of them," said author Reyu Gao.Borehole ballooning is reversible mud gains and losses to the wellbore that occur during drilling. Increased understanding and data on the phenomenon can help scientists develop preventative response measures to counteract it.Unlike previous research, which largely focused on numerical modeling, the authors' research included experimental results."Most research into borehole ballooning has been theoretical, with few experiments," said Gao. "Our device is the first professional device capable of simulating and studying the borehole ballooning under different conditions."The device, which is made up of four individual units, can simulate conditions like different fracture opening pressures, rock types, and mud circulation pressures. Its sections include the displacement unit, the triaxial clamping unit, the back-pressure unit, and the control and data acquisition system."According to the current research, the main mechanism causing borehole ballooning is the opening and closing of the fracture network around the wellbore caused by wellbore pressure fluctuations. Therefore, based on this mechanism, we first designed the core unit of the device, the triaxial clamping unit, which can simulate the opening and closing of fractures," said Gao.The researchers proved their device was able to accurately simulate the effects of borehole ballooning through experiments, and they expect these experiments to be able to validate theoretical research on the topic.

Pollution

April 23, 2020

https://www.sciencedaily.com/releases/2020/04/200423130444.htm

Falling visibility shows African cities suffering major air pollution increases

Falling visibility in three major African cities reveals that air pollution has increased significantly over the last 45 years -- leaving citizens facing further short-term increases in man-made pollution due to increasing urbanization and economic development, a new study reveals.

Africa is not well-equipped with air quality monitoring, so scientists have used visibility data for capital cities in Ethiopia, Kenya and Uganda as a substitute measurement.They discovered a significant reduction in visibility since the 1970s, where Nairobi shows the greatest loss (60%), compared to Kampala (56%) and Addis Ababa (34%) -- due to increased particulate matter (PM) emissions from vehicles and energy generation.Correspondingly, PM pollution levels in the three cities are estimated to have increased by 182%, 162% and 62% respectively since the 1970s to the current period.University of Birmingham experts published their findings in Report co-author Dr. Ajit Singh commented: "Evidence indicates that ambient air quality in urban African locations is often poor, because of high rates of urbanisation and population growth leading to large-scale construction, increased energy use, vehicle emissions and industrialisation."PM air pollution is a major concern in East Africa because of its impact on human health. There are few air quality monitoring networks, resulting in little long-term air quality data, but visibility measured at major cities can be used as a proxy for PM pollution."We're tremendously proud of our work in East Africa and the analysis techniques we developed to study Nairobi, Kampala and Addis Ababa are translatable to other parts of the world where air quality data is limited."The Birmingham team's work is funded by the UK Department for International Development (DFID) through the East Africa Research Fund (EARF) grant 'A Systems Approach to Air Pollution (ASAP) East Africa' and Digital Air Quality (DAQ) -- East Africa funded via EPSRC Global Challenges Research Fund.Co-author Dr. William Avis commented: "Air pollution poses a major health, economic and social threat to cities around the world -- inextricably linked to how we plan, manage and live in urban areas. East Africa is no exception to this, but lacks robust air quality data."Co-author and ASAP lead Professor Francis Pope said: "We need to understand the causes and effects of air pollution in these three cities, which are rapidly developing and will likely experience further increases in PM. Poor air quality acts as a brake on development through increasing expenditure on health, loss of labour productivity, and the impact of illness on education."To date, no studies have been able to assess the role of socio-economic factors upon the evolution of air pollution in East Africa. Our work provides data that helps us understand this relationship and provides a much needed baseline for East African urban air quality that can help assess future air quality improvement interventions in the region."The researchers compared changes in pollution to population growth and GDP statistics -- finding increased PM levels linked to increases in national GDP and populations in all three study cities.They also discovered distinct variations in seasonal visibility, which are largely explained by changing PM sources and sinks in rainy and dry seasons. Visibility was lowest during the dry months and highest in wet months. At all study sites, visibility was higher on Sundays -- due to reduced traffic and industrial emissions.

Pollution

April 22, 2020

https://www.sciencedaily.com/releases/2020/04/200422214046.htm

Digital agriculture paves the road to agricultural sustainability

In a study published in

Bruno Basso, professor in the College of Natural Science at Michigan State University, and John Antle, professor of Applied Economics at Oregon State University, believe the path begins with digital agriculture -- or, the integration of big data into crop and farmland usage.Digital agriculture, Basso says, is where agriculture, science, policy and education intersect. Putting that data to use requires an effective balancing of competing economic and social interests while minimizing trade-offs.Technologies like genetic modification and crop production automation help produce more food than we need to survive. And while the modern food system is a monument to human ingenuity and innovation, it is not without problems."Agriculture's contributions to greenhouse gas emissions, water pollution and biodiversity loss show that major agricultural systems are on a largely unsustainable trajectory," Basso says. "And as the population increases, energy demands and pollution will scale accordingly."Basso says that while policymakers, farmers and environmental groups are all speaking, they are not necessarily listening."There are too many barriers, too many competing interests," Basso says. "We need to bring people to the table and design a system that works for everyone -- farmers, lawmakers, society and future generations."To meet this challenge, the researchers proposed a two-step process. The initial step focuses on the design of a sustainable framework -- with goals and objectives -- guided and quantified by digital agriculture technologies. Implementation, the second step, involves increased public-private investment in technologies like digital agriculture, and a focus on applicable, effective policy.This paper links advancements in agronomic sciences to the critical role policymakers must play in implementation and setting the agenda for sustainability in agriculture."It does no good to design a policy that the farmer will ignore," Basso says. "Policymakers must make use of digital agriculture to help drive policy. Go to the farmers and say, 'we will help you make these transitions, and we will help you transform your poorly performing and unstable field areas with financial support.'"He recommends targeted tax incentives and subsidies to support farmers working toward a more sustainable system.If the objective is to increase biodiversity, to reduce nitrogen fertilizer use or to grow less resource-intensive bioenergy perennials, incentivization is key.The researchers' analysis showed that if nitrogen fertilizer applications were based on demand and yield stability instead of uniform application, usage in the Midwest could be reduced by 36% with significant reductions in groundwater contamination and carbon dioxide emissions.Basso says that we need to make these decisions as a society -- and to brunt the cost as a society. What farmers do on their land today will affect their neighbor's grandchildren in 30 years."Making use of digital agriculture is about breaking bread and creating a sustainable agricultural system. Let's bring everyone together," Basso said.

Pollution

April 22, 2020

https://www.sciencedaily.com/releases/2020/04/200422132606.htm

Spotting air pollution with satellites, better than ever before

Researchers from Duke University have devised a method for estimating the air quality over a small patch of land using nothing but satellite imagery and weather conditions. Such information could help researchers identify hidden hotspots of dangerous pollution, greatly improve studies of pollution on human health, or potentially tease out the effects of unpredictable events on air quality, such as the breakout of an airborne global pandemic.

The results appear online in the journal "We've used a new generation of micro-satellite images to estimate ground-level air pollution at the smallest spatial scale to date," said Mike Bergin, professor of civil and environmental engineering at Duke. "We've been able to do it by developing a totally new approach that uses AI/machine learning to interpret data from surface images and existing ground stations."The specific air quality measurement that Bergin and his colleagues are interested in is the amount of tiny airborne particles called PM2.5. These are particles that have a diameter of less than 2.5 micrometers -- about three percent of the diameter of a human hair -- and have been shown to have a dramatic effect on human health because of their ability to travel deep into the lungs.For example, PM2.5 was globally ranked as the fifth mortality risk factor, responsible for about 4.2 million deaths and 103.1 million years of life lost or lived with disability, by the 2015 Global Burden of Disease study. And in a recent study from the Harvard University T.H. Chan School of Public Health, researchers found that areas with higher levels of PM2.5 also are associated with higher death rates due to COVID-19.Current best practices in remote sensing to estimate the amount of ground-level PM2.5 use satellites to measure how much sunlight is scattered back to space by ambient particulates over the entire atmospheric column. This method, however, can suffer from regional uncertainties such as clouds and shiny surfaces, atmospheric mixing, and properties of the PM particles, and cannot make accurate estimates at scales smaller than about a square kilometer. While ground pollution monitoring stations can provide direct measurements, they suffer from their own host of drawbacks and are only sparsely located around the world."Ground stations are expensive to build and maintain, so even large cities aren't likely to have more than a handful of them," said Bergin. "Plus they're almost always put in areas away from traffic and other large local sources, so while they might give a general idea of the amount of PM2.5 in the air, they don't come anywhere near giving a true distribution for the people living in different areas throughout that city."In their search for a better method, Bergin and his doctoral student Tongshu Zheng turned to Planet, an American company that uses micro-satellites to take pictures of the entire Earth's surface every single day with a resolution of three meters per pixel. The team was able to get daily snapshot of Beijing over the past three years.The key breakthrough came when David Carlson, an assistant professor of civil and environmental engineering at Duke and an expert in machine learning, stepped in to help."When I go to machine learning and artificial intelligence conferences, I'm usually the only person from an environmental engineering department," said Carlson. "But these are the exact types of projects that I'm here to help support, and why Duke places such a high importance on hiring data experts throughout the entire university."With Carlson's help, Bergin and Zheng applied a convolutional neural network with a random forest algorithm to the image set, combined with meteorological data from Beijing's weather station. While that may sound like a mouthful, it's not that difficult to pick your way through the trees.A random forest is a standard machine learning algorithm that uses a lot of different decision trees to make a prediction. We've all seen decision trees, perhaps as an internet meme that uses a series of branching yes/no questions to decide whether or not to eat a burrito. Except in this case, the algorithm is looking through decision trees based on metrics such as wind, relative humidity, temperature and more, and using the resulting answers to arrive at an estimate for PM2.5 concentrations.However, random forest algorithms don't deal well with images. That's where the convolutional neural networks come in. These algorithms look for common features in images such as lines and bumps and begin grouping them together. As the algorithm "zooms out," it continues to lump similar groupings together, combining basic shapes into common features such as buildings and highways. Eventually the algorithm comes up with a summary of the image as a list of its most common features, and these get thrown into the random forest along with the weather data."High-pollution images are definitely foggier and blurrier than normal images, but the human eye can't really tell the exact pollution levels from those details," said Carlson. "But the algorithm can pick out these differences in both the low-level and high-level features -- edges are blurrier and shapes are obscured more -- and precisely turn them into air quality estimates.""The convolutional neural network doesn't give us as good of a prediction as we would like with the images alone," added Zheng. "But when you put those results into a random forest with weather data, the results are as good as anything else currently available, if not better."In the study, the researchers used 10,400 images to train their model to predict local levels of PM2.5 using nothing but satellite images and weather conditions. They tested their resulting model on another 2,622 images to see how well it could predict PM2.5.They show that, on average, their model is accurate to within 24 percent of actual PM2.5 levels measured at reference stations, which is at the high end of the spectrum for these types of models, while also having a much higher spatial resolution. While most of the current standard practices can predict levels down to 1 million square meters, the new method is accurate down to 40,000 -- about the size of eight football fields placed side-by-side.With that level of specificity and accuracy, Bergin believes their method will open up a wide range of new uses for such models."We think this is a huge innovation in satellite retrievals of air quality and will be the backbone of a lot of research to come," said Bergin. "We're already starting to get inquiries into using it to look at how levels of PM2.5 are going to change once the world starts recovering from the spread of COVID-19."

Pollution

April 22, 2020

https://www.sciencedaily.com/releases/2020/04/200422091142.htm

Carbon dioxide sensor can lower energy use, reduce utility costs

Walk in a room, the light goes on. Most people are familiar with the motion sensors that detect activity and then turn on the lights.

Purdue University researchers are turning to similar technologies to help manage climate control and indoor air quality. They have developed a sensor to help control and cut down on energy consumption through heating and ventilation systems, particularly those used in large office and hospitality industry buildings."Climate control and proper ventilation are especially important because most people spend considerably more time indoors than outside," said Jeff Rhoads, a professor of mechanical engineering in Purdue's College of Engineering. "Climate control and ventilation are also huge sources of energy consumption in the United States and around the world."Rhoads and his team have developed a lower-cost, lower-energy carbon dioxide sensor that could change the way energy is used to heat, cool and ventilate large buildings and eventually homes.The Purdue project is supported by ARPA-E, the Advanced Research Projects Agency -- Energy, a government agency tasked with promoting and funding research and development of advanced energy technologies.The technology identifies when carbon dioxide is released into the air by a person, or people entering and breathing inside that space.The Purdue sensor detects the carbon dioxide so that heating and ventilation systems can control the climate and air turnover in spaces that are occupied, instead of using energy to control rooms that are empty."We leverage two technologies with our innovative device: resonant sensing and resistive sensing," said Rhoads, a leading sensor researcher who serves as the director of Purdue's Ray W. Herrick Labs. "We use them in combination to detect carbon dioxide. This is a great alternative to available technologies that may not reliably measure carbon dioxide while remaining competitive in cost and power consumption."Rhoads said the Purdue sensor also helps address privacy concerns about using camera technology for detecting when someone enters and leaves a room.The team, which includes professors Bryan Boudouris from Purdue's School of Chemical Engineering, and Jim Braun and George Chiu from Purdue's School of Mechanical Engineering, is working to integrate the sensor with other Internet of Things building technology.

Pollution

April 20, 2020

https://www.sciencedaily.com/releases/2020/04/200420145031.htm

Faster-degrading plastic could promise cleaner seas

To address plastic pollution plaguing the world's seas and waterways, Cornell University chemists have developed a new polymer that can degrade by ultraviolet radiation, according to research published in the

"We have created a new plastic that has the mechanical properties required by commercial fishing gear. If it eventually gets lost in the aquatic environment, this material can degrade on a realistic time scale," said lead researcher Bryce Lipinski, a doctoral candidate in the laboratory of Geoff Coates, professor of chemistry and chemical biology at Cornell University. "This material could reduce persistent plastic accumulation in the environment."Commercial fishing contributes to about half of all floating plastic waste that ends up in the oceans, Lipinski said. Fishing nets and ropes are primarily made from three kinds of polymers: isotactic polypropylene, high-density polyethylene, and nylon-6,6, none of which readily degrade."While research of degradable plastics has received much attention in recent years," he said, "obtaining a material with the mechanical strength comparable to commercial plastic remains a difficult challenge."Coates and his research team have spent the past 15 years developing this plastic called isotactic polypropylene oxide, or iPPO. While its original discovery was in 1949, the mechanical strength and photodegradation of this material was unknown before this recent work. The high isotacticity (enchainment regularity) and polymer chain length of their material makes it distinct from its historic predecessor and provides its mechanical strength.Lipinski noted that while iPPO is stable in ordinary use, it eventually breaks down when exposed to UV light. The change in the plastic's composition is evident in the laboratory, but "visually, it may not appear to have changed much during the process," he said.The rate of degradation is light intensity-dependent, but under their laboratory conditions, he said, the polymer chain lengths degraded to a quarter of their original length after 30 days of exposure.Ultimately, Lipinski and other scientists want to leave no trace of the polymer in the environment. He notes there is literature precedent for the biodegradation of small chains of iPPO which could effectively make it disappear, but ongoing efforts aim to prove this.This research was supported by the National Science Foundation's Center for Sustainable Polymers, the NSF-supported NMR Facility at Cornell, and the Cornell Center for Materials Research.

Pollution

April 20, 2020

https://www.sciencedaily.com/releases/2020/04/200420125440.htm

What did scientists learn from Deepwater Horizon?

Ten years ago, a powerful explosion destroyed an oil rig in the Gulf of Mexico, killing 11 workers and injuring 17 others. Over a span of 87 days, the Deepwater Horizon well released an estimated 168 million gallons of oil and 45 million gallons of natural gas into the ocean, making it the largest accidental marine oil spill in history.

Researchers from Woods Hole Oceanographic Institution (WHOI) quickly mobilized to study the unprecedented oil spill, investigating its effects on the seafloor and deep-sea corals and tracking dispersants used to clean up the spill.In a review paper published in the journal "So many lessons were learned during the Deepwater Horizon disaster that it seemed appropriate and timely to consider those lessons in the context of a review," says Kujawinski. "We found that much good work had been done on oil weathering and oil degradation by microbes, with significant implications for future research and response activities.""At the end of the day, this oil spill was a huge experiment," adds Reddy. "It shed great light on how nature responds to an uninvited guest. One of the big takeaways is that the oil doesn't just float and hang around. A huge amount of oil that didn't evaporate was pummeled by sunlight, changing its chemistry. That's something that wasn't seen before, so now we have insight into this process."Released for the first time in a deep ocean oil spill, chemical dispersants remain one of the most controversial debates in the aftermath of Deepwater Horizon. Studies offer conflicting conclusions about whether dispersants released in the deep sea reduced the amount of oil that reached the ocean surface, and the results are ambiguous about whether dispersants helped microbes break down the oil at all."I think the biggest unknowns still center on the impact of dispersants on oil distribution in seawater and their role in promoting -- or inhibiting -- microbial degradation of the spilled oil," says Kujawinski, whose lab was the first to identify the chemical signature of the dispersants, making it possible to track in the marine environment.Though the authors caution that the lessons learned from the Deepwater Horizon release may not be applicable to all spills, the review highlights advances in oil chemistry, microbiology, and technology that may be useful at other deep-sea drilling sites and shipping lanes in the Arctic. The authors call on the research community to work collaboratively to understand the complex environmental responses at play in cold climates, where the characteristics of oil are significantly different from the Gulf of Mexico."Now we have a better sense of what we need to know," Kujawinski says. "Understanding what these environments look like in their natural state is really critical to understanding the impact of oil spill conditions."

Pollution

April 20, 2020

https://www.sciencedaily.com/releases/2020/04/200420125436.htm

Study describes cocktail of pharmaceuticals in waters in Bangladesh

In spring of 2019, researchers set out to investigate what chemicals could be found in the waters of Bangladesh.

The scientists -- from the University at Buffalo and icddr,b, a leading global health research institute in Bangladesh -- tested a lake, a canal and a river in Dhaka, Bangladesh's capital and the nation's largest city. The team also sampled water from ditches, ponds and drinking wells in a rural area known as Matlab.In the lab, an analysis revealed that the waters held a cocktail of pharmaceuticals and other compounds, including antibiotics, antifungals, anticonvulsants, anesthetics, antihypertensive drugs, pesticides, flame retardants and more.Not all of these chemicals were found at every location, and sometimes amounts detected were low.But the ubiquity of contamination is concerning, says lead scientist Diana Aga, an environmental chemist at UB."When we analyzed all these samples of water from Bangladesh, we found fungicides and a lot of antibiotics we weren't looking for," says Aga, PhD, Henry M. Woodburn Professor of Chemistry in the UB College of Arts and Sciences. "This kind of pollution is a problem because it can contribute to the development of bacteria and fungi that are resistant to the medicines we have for treating human infection."The study appears in the April 10 volume of the journal Compounds the team found at every sampling site included the antifungal agent carbendazim, flame retardants and the insect repellent DEET.The canal and river in Dhaka contained a medley of chemicals. Of note, scientists discovered multiple varieties of antibiotics at these two sites, along with antifungals. While researchers generally found fewer antimicrobials at the rural test locations, some antibiotics were found at certain sites, and antifungal agents were common."The fact that we found so many different types of chemicals is really concerning," Aga says. "I recently saw a paper, a lab study, that showed exposure to antidepressants put pressure on bacteria in a way that caused them to become resistant to multiple antibiotics. So it's possible that even chemicals that are not antibiotics could increase antibacterial resistance."Aga's team included first author Luisa F. Angeles, a PhD candidate in UB's Department of Chemistry, who traveled to Bangladesh to sample water and train scientists there on sample collection and preparation techniques.Afterward, Aga, Angeles and colleagues studied the water in their Buffalo laboratory using state-of-the-art analytical methods.In the past, technological limitations meant scientists could only test samples for specific targeted chemicals. Aga's team was able to employ a more advanced form of analysis that screens samples for a huge variety of pollutants -- checking for more than 1,000 potential compounds in this case, including ones the researchers did not anticipate finding.The discovery of antimicrobials in urban areas was not surprising, as these chemicals are often found in human urine and later in wastewater that's released into rivers, Aga says. She thinks at rural sites, the presence of antibiotics and antifungals in water may be due to the fact that people may be using these chemicals to protect food crops and farm animals."It's important to note that antimicrobial contamination of the environment is not unique to Bangladesh, but expected in many countries throughout the world where antimicrobial use is poorly regulated in both human medicine and agriculture, which is generally the case in lower-middle income countries of Asia," says study co-author Shamim Islam, MD, clinical associate professor of pediatrics in the Jacobs School of Medicine and Biomedical Sciences at UB.Islam adds that, "As undertaken in this study, we feel analyzing and characterizing such environmental antimicrobial contamination is a critically important component of global antimicrobial resistance surveillance and mitigation efforts."

Pollution

April 20, 2020

https://www.sciencedaily.com/releases/2020/04/200420105047.htm

A cheap organic steam generator to purify water

It has been estimated that in 2040 a quarter of the world's children will live in regions where clean and drinkable water is lacking. The desalination of seawater and the purification of wastewater are two possible methods to alleviate this, and researchers at Linköping University have developed a cheap and eco-friendly steam generator to desalinate and purify water using sunlight. The results have been published in the journal

"The rate of steam production is 4-5 times higher than that of direct water evaporation, which means that we can purify more water," says Associated Professor Simone Fabiano, head of the Organic Nanoelectronics group in the Laboratory of Organic Electronics.The steam generator consists of an aerogel that contains a cellulose-based structure decorated with the organic conjugated polymer PEDOT:PSS. The polymer has the ability to absorb the energy in sunlight, not least in the infrared part of the spectrum where much of the sun's heat is transported. The aerogel has a porous nanostructure, which means that large quantities of water can be absorbed into its pores."A 2 mm layer of this material can absorb 99% of the energy in the sun's spectrum," says Simone Fabiano.A porous and insulating floating foam is also located between the water and the aerogel, such that the steam generator is kept afloat. The heat from the sun vaporises the water, while salt and other materials remain behind."The aerogel is durable and can be cleaned in, for example, salt water such that it can be used again immediately. This can be repeated many times. The water that passes through the system by evaporation becomes very high-quality drinking water," Tero-Petri Ruoko assures us. He is postdoc in the Laboratory of Organic Electronics and one of the authors of the article."What's particularly nice about this system is that all the materials are eco-friendly -- we use nanocellulose and a polymer that has a very low impact on the environmental and people. We also use very small amounts material: the aerogel is made up of 90% air. We hope and believe that our results can help the millions of people who don't have access to clean water," says Simone Fabiano.The aerogel was developed by Shaobo Han within the framework of his doctoral studies in the Laboratory of Organic Electronics, under Professor Xavier Crispin´s supervision. The result was presented in the journal Advanced Science in 2019, and is described at the link below. After taking his doctoral degree, Shaobo Han has returned to China to continue research in the field.

Pollution

April 16, 2020

https://www.sciencedaily.com/releases/2020/04/200416091941.htm

New geochemical tool reveals origin of Earth's nitrogen

Researchers at Woods Hole Oceanographic Institution (WHOI), the University of California Los Angeles (UCLA) and their colleagues used a new geochemical tool to shed light on the origin of nitrogen and other volatile elements on Earth, which may also prove useful as a way to monitor the activity of volcanoes. Their findings were published April 16, 2020, in the journal

Nitrogen is the most abundant gas in the atmosphere, and is the primary component of the air we breathe. Nitrogen is also found in rocks, including those tucked deep within the planet's interior. Until now, it was difficult to distinguish between nitrogen sources coming from air and those coming from inside the Earth's mantle when measuring gases from volcanoes."We found that air contamination was masking the pristine 'source signature' of many volcanic gas samples," says WHOI geochemist Peter Barry, a coauthor of the study.Without that distinction, scientists weren't able to answer basic questions like: Is nitrogen left over from Earth's formation or was it delivered to the planet later on? How is nitrogen from the atmosphere related to nitrogen coming out of volcanoes?Barry and lead author Jabrane Labidi of UCLA, now a researcher at Institut de Physique du Globe de Paris, worked in partnership with international geochemists to analyze volcanic gas samples from around the globe -- including gases from Iceland and Yellowstone National Park -- using a new method of analyzing "clumped" nitrogen isotopes. This method provided a unique way to identify molecules of nitrogen that come from air, which allowed the researchers to see the true gas compositions deep within Earth's mantle. This ultimately revealed evidence that nitrogen in the mantle has most likely been there since our planet initially formed."Once air contamination is accounted for, we gained new and valuable insights into the origin of nitrogen and the evolution of our planet," Barry says.While this new method helps scientists understand the origins of volatile elements on Earth, it may also prove useful as a way of monitoring the activity of volcanoes. This is because the composition of gases bellowing from volcanic centers change prior to eruptions. It could be that the mix of mantle and air nitrogen could one day be used as a signal of eruptions.This study was supported by the Deep Carbon Observatory and the Alfred P. Sloan Foundation. The research team also included colleagues David Bekaert and Mark Kurz from WHOI, scientists from several other U.S.-based universities, and from France, Canada, Italy, the United Kingdom and Iceland.

Pollution

April 15, 2020

https://www.sciencedaily.com/releases/2020/04/200415084314.htm

Breathing heavy wildfire smoke may increase risk of out-of-hospital cardiac arrest

Exposure to heavy smoke during recent California wildfires raised the risk of out-of-hospital cardiac arrests up to 70%, according to new research published today in the

Cardiac arrest occurs when the heart abruptly stops beating properly and can no longer pump blood to vital organs throughout the body. While often referred to interchangeably, cardiac arrest is not the same as a heart attack. A heart attack is when blood flow to the heart is blocked, and sudden cardiac arrest is when the heart malfunctions and suddenly stops beating unexpectedly. A heart attack is a "circulation" problem and sudden cardiac arrest is an "electrical" problem. Out-of-hospital cardiac arrests (OHCAs) are more dangerous because they can lead to death within minutes if no one performs CPR or uses a defibrillator to shock the heart back into a normal rhythm.The natural cycle of large-scale wildfires is accelerating and exposing both rural and urban communities to wildfire smoke, according to the study. While adverse respiratory effects associated with wildfire smoke are well established, cardiovascular effects are less clear."In recent decades, we experienced a significant increase in large-scale wildfires, therefore, more people are being exposed to wildfire smoke. In order to respond properly, it is important for us to understand the health impacts of wildfire smoke exposure," said study author Ana G. Rappold, Ph.D., a research scientist at the U.S. Environmental Protection Agency's Center for Public Health and Environmental Assessment in the Office of Research and Development.Researchers examined cardiac arrests during 14 wildfire-affected counties in California between 2015 and 2017, using information submitted to a health registry established by the Centers for Disease Control and Prevention, and the Cardiac Arrest Registry to Enhance Survival (CARES). Smoke density exposure was rated as light, medium or heavy according to mapping data from the National Oceanic and Atmospheric Association. The researchers compared smoke exposure on the day of the OHCA to the exposure on the same day of the week in the 3 prior weeks. They also compared the exposure 1, 2 and 3 days before the OHCA to the exposure on the corresponding days in 3 weeks prior to the cardiac arrest.The analysis found that the risk of out-of-hospital cardiac arrests:"Particulate matter from smoke that is inhaled can penetrate deeply into the lungs, and very small particles may cross into the bloodstream. These particles can create an inflammatory reaction in the lungs and throughout the body. The body's defense system may react to activate the fight-or-flight system, increasing heart rate, constricting blood vessels and increasing blood pressure. These changes can lead to disturbances in the heart's normal rhythm, blockages in blood vessels and other effects creating conditions that could lead to cardiac arrest," Rappold said.Although the researchers had no information about the actions taken by individuals, the increased risk they found in people living in lower-income communities might reflect less access to strategies to reduce exposure. Previous studies have shown that there are more respiratory problems in lower-income communities and worsening congestive heart failure in response to wildfire smoke exposure."People in a higher socioeconomic status group who have pre-existing cardiopulmonary conditions may be better able to take effective action to decrease exposure, such as staying indoors, using portable air filters or using effective respirator masks. They may also be more likely to live in homes with air conditioning and efficient air filtration," Rappold said."While other studies have found that older adults are more affected, we also observed elevated effects among middle-aged adults (aged 35-64). It is possible that this population may not be aware of their risk and may not have flexibility to discontinue activities that involve exertion and exposure during wildfire smoke episodes," concluded Rappold.To reduce exposure to wildfire smoke, researchers advise people to stay indoors with doors and windows closed, to use high-efficiency air filters in air conditioning systems, avoid exertion, and consider seeking shelter elsewhere if the home does not have an air conditioner and it is too warm to stay inside.The small sample size limited the researchers' ability to determine how the risks of smoke exposure might differ among people of different ages and genders. Individuals with personal health questions or concerns should consult with their doctor, researchers said.

Pollution

April 15, 2020

https://www.sciencedaily.com/releases/2020/04/200415084307.htm

First Gulf of Mexico-wide survey of oil pollution completed 10 years after Deepwater Horizon

Since the 2010 BP oil spill, marine scientists at the University of South Florida (USF) have sampled more than 2,500 individual fish representing 91 species from 359 locations across the Gulf of Mexico and found evidence of oil exposure in all of them, including some of the most popular types of seafood. The highest levels were detected in yellowfin tuna, golden tilefish and red drum.

The study, just published in Nature Over the last decade, USF scientists conducted a dozen research expeditions to locations off the United States, Mexico and Cuba examining levels of polycyclic aromatic hydrocarbons (PAHs), the most toxic chemical component of crude oil, in the bile of the fish. Bile is produced by the liver to aid in digestion, but it also acts as storage for waste products."We were quite surprised that among the most contaminated species was the fast-swimming yellowfin tuna as they are not found at the bottom of the ocean where most oil pollution in the Gulf occurs," said lead author Erin Pulster, a researcher in USF's College of Marine Science. "Although water concentrations of PAHs can vary considerably, they are generally found at trace levels or below detection limits in the water column. So where is the oil pollution we detected in tunas coming from?"Pulster says it makes sense that tilefish have higher concentrations of PAH because they live their entire adult lives in and around burrows they excavate on the seafloor and PAHs are routinely found in Gulf sediment. However, their exposure has been increasing over time, as well as in other species, including groupers, some of Florida's most economically important fish. In a separate USF-led study, her team measured the concentration of PAHs in the liver tissue and bile of 10 popular grouper species. The yellowedge grouper had a concentration that increased more than 800 percent from 2011 to 2017.Fish with the highest concentrations of PAH were found in the northern Gulf of Mexico, a region of increased oil and gas activity and in the vicinity of the Deepwater Horizon spill that gushed nearly four million barrels of oil over the course of three months in 2010. Oil-rich sediments at the bottom where much of the oil settled are resuspended by storms and currents, re-exposing bottom-dwelling fish.Oil pollution hot spots were also found off major population centers, such as Tampa Bay, suggesting that runoff from urbanized coasts may play a role in the higher concentrations of PAHs. Other sources include chornic low-level releases from oil and gas platforms, fuel from boats and airplanes and even natural oil seeps -- fractures on the seafloor that can ooze the equivalent of millions of barrels of oil per year."This was the first baseline study of its kind, and it's shocking that we haven't done this before given the economic value of fisheries and petroleum extraction in the Gulf of Mexico," said Steven Murawksi, professor of fisheries biology at USF, who led the international research effort.Despite the detected trends of oil contamination in fish bile and liver, fish from the Gulf of Mexico are rigorously tested for contaminants to ensure public safety and are safe to eat because oil contaminants in fish flesh are well below public health advisory levels. Chronic PAH exposure, however, can prevent the liver from functioning properly, resulting in the decline of overall fish health.These studies were made possible by BP's 10-year, $500 million commitment to fund independent research on the long-term effects of the Deepwater Horizon spill administered by the Gulf of Mexico Research Initiative. This year marks the end of that funding."Long-term monitoring studies such as these are important for early warning of oil pollution leaks and are vital for determining impacts to the environment in the case of future oil spills," Pulster said.

Pollution

April 15, 2020

https://www.sciencedaily.com/releases/2020/04/200415110459.htm

Soot may only be half the problem when it comes to cookstoves

A telltale signature of a cookstove, commonly used to prepare food or provide heat by burning wood, charcoal, animal dung or crop residue, is the thick, sooty smoke that rises from the flames. Its remnants, black stains left on the walls and clothes and in the lungs of the people -- usually women -- who tend to the stoves, are a striking reminder of the hazards the stoves pose both to human health and to the environment.

But soot is only part of the story when it comes to environmental impact -- about half of it, it turns out.As the temperatures in a cookstove begin to drop, and the black smoke turns greyish-white, soot (or black carbon) emission is replaced by organic carbon.Research from the McKelvey School of Engineering at Washington University in St. Louis has revealed that, despite its whitish appearance, organic carbon particles absorb as much -- if not more -- sunlight in the atmosphere as black carbon. And its health effects may be worse for the nearly 2.7 billion households worldwide that use them.The research was published in the April 14, 2020, issue of To better understand the effects cookstoves are having on the environment and human health, Rajan Chakrabarty, assistant professor of energy, environmental and chemical engineering, took his research to a pollution hotspot: Chhattisgarh, in the heart of rural central India, where cookstoves are one of the biggest emitters of aerosols and greenhouse gases."Previous experiments had been carried out in a lab under controlled conditions, which are different from what you'll find in the field," Chakrabarty said.Yet global mitigation and policy strategies have for 15 years been influenced by a 2005 study based on experiments carried out in a lab. That paper recommended controlling black carbon as a way to mitigate climate change in the South Asian region.To better understand the effects of cookstove emissions in the field, Chakrabarty's team headed to Chhattisgarh, between New Delhi and Calcutta. For two weeks, they lived with residents in rural homes where people used mud chulhas, or cookstoves, to prepare food. During that time, they ran 30 tests, cooking with different fuels: wood, agricultural residue and cattle dung, all of which were locally sourced.The success of their field study was greatly facilitated by local researcher and Chakrabarty's longtime collaborator, Professor Shamsh Pervez and his research group at Pt. Ravishankar Shukla University."We found the reality of a cooking cycle is a mix of black and white smoke," Chakrabarty said. The color black absorbs light, and white reflects it. "We had thought that the organic carbons counteracted the black carbon, to a degree," he said. "Soot absorbs, organics scatter."What they found was something different. The particulates in the white smoke were absorbing light very strongly in the near ultraviolet wavelengths. "When we looked under the hood," Chakrabarty said, "they were actually brown carbon." After completing the analysis, the team determined the absorption was equally if not greater than black carbon, making it an equally potent agent of atmospheric warming.Burning biomass fuel, such as wood or dung, is the dominant source of ambient air pollution particles in the South Asian region, according to Chandra Venkataraman, professor of chemical engineering at the Indian Institute of Technology Bombay. Venkataraman was the first author of that influential 2005 Science paper."This work makes a novel and crucial finding, using field measurements of particulate emissions from biomass stoves, that radiation absorption from the organic carbon component could equal that from black carbon," she said.Beyond its effects on the climate, organic carbon also poses significant health risks. Many of the particulates are what are known as high molecular weight polycyclic aromatic hydrocarbons -- compounds of carbon and hydrogen that are established carcinogens in animals and generally believed to be so in humans.Chakrabarty's findings are applicable around the world, as the World Health Organization reports nearly half of the world's population cooks over an open fire. Cookstoves can be found in homes not only in India, but around the globe, from Senegal to Peru to Albania."The finding has very significant implications for regional atmospheric warming from pollution particles containing short-lived climate forcers like black and organic carbon in the context of achieving Paris Agreement temperature targets," Venkataraman said.

Pollution

April 13, 2020

https://www.sciencedaily.com/releases/2020/04/200413140507.htm

Offshore oil and gas platforms release more methane than previously estimated

Offshore energy-producing platforms in U.S. waters of the Gulf of Mexico are emitting twice as much methane, a greenhouse gas, than previously thought, according to a new study from the University of Michigan.

Researchers conducted a first-of-its-kind pilot-study sampling air over offshore oil and gas platforms in the Gulf of Mexico. Their findings suggest the federal government's calculations are too low.U-M's research found that, for the full U.S. Gulf of Mexico, oil and gas facilities emit approximately one-half a teragram of methane each year, comparable with large emitting oil and gas basins like the Four Corners region in the southwest U.S. The effective loss rate of produced gas is roughly 2.9%, similar to large onshore basins primarily focused on oil, and significantly higher than current inventory estimates.Offshore harvesting accounts for roughly one-third of the oil and gas produced worldwide, and these facilities both vent and leak methane. Until now, only a handful of measurements of offshore platforms have been made, and no aircraft studies of methane emissions in normal operation had been conducted. Each year the EPA issues its U.S. Greenhouse Gas Inventory, but its numbers for offshore emissions are not produced via direct sampling.The study, published in Errors in platform counts: Offshore facilities in state waters, of which there are in excess of 1,300, were missing from the U.S. Greenhouse Gas Inventory.Persistent emissions from shallow-water facilities, particularly those primarily focused on natural gas, are higher than inventoried.Large, older facilities situated in shallow waters tended to produce episodic, disproportionally high spikes of methane emissions. These facilities, which have more than seven platforms apiece, contribute to nearly 40% of emissions, yet consist of less than 1% of total platforms. If this emission process were identified, it could provide an optimal mitigation opportunity, the researchers said.Eric Kort, a U-M associate professor of climate and space sciences and engineering, said EPA officials are already making adjustments to correct their count of offshore platforms operating in the Gulf of Mexico. But emissions estimates, particularly for shallow waters, still need adjustments."We have known onshore oil and gas production often emits more methane than inventoried. With this study we show that this is also the case for offshore production, and that these discrepancies are large," Kort said. "By starting to identify and quantify the problem, with a particular focus on larger shallow water facilities, we can work towards finding optimal mitigation solutions."In addition, those shallow-water discrepancies warrant further investigation, Kort added, since deep water facilities may be sending some of the oil and gas they produce via pipeline to others located closer to shore.U-M's team conducted its sampling in 2018 with Scientific Aviation using a small research plane with enough room for a pilot and passenger in the two front seats, as well as scientific gear where there normally would be two rear two seats. Tubes along the wings of the plane drew in air that was pumped to the equipment for analysis of the amount of methane included as well as wind speed. Circling a single platform gives researchers a better idea of how much methane that single source is emitting.In addition to 12 individual facilities, the flights also covered larger geographical areas. Flying downwind from clusters of 5 to 70 oil and gas facilities, and taking similar measurements, researchers can evaluate how well inventory estimates compare with large numbers of platforms."By measuring emissions from both individual facilities as well as many dozens of facilities we can compare results, evaluate different inventories, and generate a more statistically robust estimate of total emissions from the U.S. Gulf of Mexico," said Alan Gorchov Negron, lead author on the study and a Ph.D. candidate in climate sciences at U-M.As a pilot study, Kort said the research is promising but has gaps. Greater statistical sampling and identification of the cause of high emissions can guide mitigation and improve reported emissions. To further the work and fill in these gaps, new aerial sampling is in the works funded by the Alfred P. Sloan Foundation. The project, titled Flaring and Fossil Fuels: Uncovering Emissions & Losses (F³UEL), will mean more flights later over the next three years over the Gulf of Mexico, Alaska and California.The research was funded by the Climate and Clean Air Coalition Oil and Gas Methane Science Studies (managed by the UN) and the Alfred P. Sloan Foundation.

Pollution

April 8, 2020

https://www.sciencedaily.com/releases/2020/04/200408220548.htm

Improving accuracy of future climate change predictions

New research published by NUI Galway's Centre for Climate & Air Pollution Studies (C-CAPS) has shone light on the impact of clouds on climate change. The study has raised serious doubts of the likely impact of human-led interventions involving methods of cloud 'brightening' to counteract climate change. The new study has been published today in the Nature's journal --

The study looks into clouds, with one of the most important types of elements in clouds thought to be sulphate. Clouds, which are made of many droplets of condensed water on air particles, cool the climate by reflecting sunlight. According to recent theories, more air pollution serves as condensation points for cloud droplets leading to more solar reflectance. This has led many to believe that fossil fuel emissions and other air pollutions may off-set global warming through cloud 'brightening'.The Galway study found the addition of a small amount of sea-salt can dampen the effect of clouds becoming brighter as a result of increased sulphate in the atmosphere. Professor Colin O'Dowd, Director of C-CAPS and Established Chair of Atmospheric Physics, said: "The study backs up our previous thinking that sea-salt will factor out other substances and cause competition between potential nuclei influencing cloud reflectance. This means that recent theories that increased sulphate production can decrease the impact of climate change need to be reconsidered. Science is clearly pointing to the fact that carbon-based human activity is hurting our environment and there's only one pathway to solve this -- less fossil fuel and no interference with nature."Researchers from NUI Galway joined the Spanish research vessel BIO Hesperides circling Antarctica's Southern Ocean, known as the world's cleanest laboratory. The purpose of the expedition was to examine how the world's atmosphere is functioning in a pollution free environment.Lead author Dr Kirsten Fossum commented: "Clouds, particularly those overlying dark ocean surfaces, are the Earth's key climate regulators, accounting for half of global reflectance. Pollution-induced changes to cloud reflectance, represent the single biggest uncertainty in predicting future climate change. The large area covered and systematic evidence from the cruise to Antarctica provided the vast sample of clean air needed to conclusively support this study."The study was funded by SFI and the Spanish Ministry of Economy and Competitiveness. The Antarctic cruise that led to this study was organised by the Institut de Ciéncies del Mar (CSIC), Barcelona, Catalonia, Spain.The researchers behind the study run the Mace Head Air Pollution and Climate Laboratory on the west coast of Ireland where they study the cleanest air in Europe and in the northern hemisphere. The team also recently released a unique smartphone app, known as StreamAir, it provides real-time weather forecasting and highlights key drivers of air pollution and climate disruption through air quality indications.

Pollution

April 8, 2020

https://www.sciencedaily.com/releases/2020/04/200408145801.htm

Babies in popular low-riding pushchairs are exposed to alarming levels of toxic air pollutants

Parents who are using popular low-riding pushchairs could be exposing their babies to alarming levels of air pollution, finds a new study from the University of Surrey.

In a paper published by The study looked at three different pushchair types -- single pushchairs facing the road, single pushchair facing the adult and double pushchairs facing the road -- and assessed the difference in concentration of pollutants compared to those experienced by adults. The GCARE team also investigated whether pushchair covers altered exposure levels.The team simulated 89 school drop off and pick up trips in Guildford, Surrey, walking just over 2km, between the times of 8am to 10am and 3pm to 5pm.Significantly, the team found that on average, regardless of the type of pushchair, babies could be breathing 44 per cent more harmful pollutants than their parents during both morning and afternoon school runs.The GCARE team also found that a child at the bottom of a double pushchair faced up to 72 per cent higher exposure to pollutants than a child on the top seat.However, the team from Surrey found a ray of hope in the form of pushchair covers, discovering that they reduced concentration of small-sized particles by as much as 39 per cent.Professor Prashant Kumar, Founding Director of GCARE at the University of Surrey, said: "For parents, nothing is more important than the health of our children and this is why we at the University of Surrey are continuing to build on this research to understand the impact air pollution has on babies travelling in pushchairs."Our research shows that choices such as the type of pushchair you use, can impact on the amount of pollution your child faces when you are running a typical errand. But there is cause for some optimism, as our study confirms that pushchair covers and upping the buggy heights appears to have shielded children from an appreciable amount of pollution under certain conditions."

Pollution

April 8, 2020

https://www.sciencedaily.com/releases/2020/04/200408104950.htm

New study helps improve accuracy of future climate change predictions

New research published by NUI Galway's Centre for Climate & Air Pollution Studies (C-CAPS) has shone light on the impact of clouds on climate change. The study has raised serious doubts of the likely impact of human-led interventions involving methods of cloud 'brightening' to counteract climate change. The new study has been published today in the Nature's journal --

The study looks into clouds, with one of the most important types of elements in clouds thought to be sulphate. Clouds, which are made of many droplets of condensed water on air particles, cool the climate by reflecting sunlight. According to recent theories, more air pollution serves as condensation points for cloud droplets leading to more solar reflectance. This has led many to believe that fossil fuel emissions and other air pollutions may off-set global warming through cloud 'brightening'.The Galway study found the addition of a small amount of sea-salt can dampen the effect of clouds becoming brighter as a result of increased sulphate in the atmosphere. Professor Colin O'Dowd, Director of C-CAPS and Established Chair of Atmospheric Physics, said: "The study backs up our previous thinking that sea-salt will factor out other substances and cause competition between potential nuclei influencing cloud reflectance. This means that recent theories that increased sulphate production can decrease the impact of climate change need to be reconsidered. Science is clearly pointing to the fact that carbon-based human activity is hurting our environment and there's only one pathway to solve this -- less fossil fuel and no interference with nature."Researchers from NUI Galway joined the Spanish research vessel BIO Hesperides circling Antarctica's Southern Ocean, known as the world's cleanest laboratory. The purpose of the expedition was to examine how the world's atmosphere is functioning in a pollution free environment.Lead author Dr Kirsten Fossum commented: "Clouds, particularly those overlying dark ocean surfaces, are the Earth's key climate regulators, accounting for half of global reflectance. Pollution-induced changes to cloud reflectance, represent the single biggest uncertainty in predicting future climate change. The large area covered and systematic evidence from the cruise to Antarctica provided the vast sample of clean air needed to conclusively support this study."The study was funded by SFI and the Spanish Ministry of Economy and Competitiveness. The Antarctic cruise that led to this study was organised by the Institut de Ciéncies del Mar (CSIC), Barcelona, Catalonia, Spain.The researchers behind the study run the Mace Head Air Pollution and Climate Laboratory on the west coast of Ireland where they study the cleanest air in Europe and in the northern hemisphere. The team also recently released a unique smartphone app, known as StreamAir, it provides real-time weather forecasting and highlights key drivers of air pollution and climate disruption through air quality indications.

Pollution

April 8, 2020

https://www.sciencedaily.com/releases/2020/04/200408104929.htm

Lobster digestion of microplastics could further foul the food chain

Tiny fragments of plastic waste are dispersed throughout the environment, including the oceans, where marine organisms can ingest them. However, the subsequent fate of these microplastics in animals that live near the bottom of the ocean isn't clear. Now, researchers report in ACS'

Microplastic pollution that makes its way into the ocean eventually sinks to the seabed. In lobsters collected near Sardinia in the Mediterranean Sea, the researchers found that larger plastic particles became trapped in the crustaceans' stomachs. However, some particles passed into the "gastric mill," a complex of small calcified plates that grind against each other to break down food in a lobster's stomach. This process fragmented some of the plastic into smaller particles, which then moved on to the lobsters' intestines. In live animals, these smaller fragments would presumably be expelled into the ocean. These findings highlight the existence of a new kind of "secondary" microplastic, introduced into the environment by living organisms, that could represent a significant pathway of plastic degradation in the deep sea, the authors say. They also note that these tinier particles could then be more bioavailable to smaller creatures in the deep-sea food chain.

Pollution

April 7, 2020

https://www.sciencedaily.com/releases/2020/04/200407164953.htm

River-groundwater hot spot for arsenic

Naturally occurring (geogenic) groundwater arsenic contamination is a problem of global significance, with noteworthy occurrences in large parts of the alluvial and deltaic aquifers in South and Southeast Asia. To address this problem tremendous research efforts have been dedicated over the last two decades to better understand the sources and distribution of arsenic-polluted groundwater. Now, an Australian team of scientists from Flinders University, CSIRO and the University of Western Australia, together with their colleagues at the Swiss Federal Institute of Aquatic Science and Technology (Eawag), have used computer modelling to integrate much of what has been learned over the years into computer simulations that mimic the complex interactions between groundwater flow, solute transport and geochemical reaction mechanisms. Such models are important to analyse field observations, to unravel which chemical and physical processes play a role, and to predict the behaviour of arsenic within aquifers -- where and when pollution may occur in the future. The results of their study have now been published in the latest issue of

The research team selected a highly arsenic polluted site near Hanoi (Vietnam) to develop and test their computer model. In a first step they used the tiny concentrations of tritium that had entered the groundwater system from the atmosphere during the times of nuclear bomb testing, and its decay product helium, a noble gas, to reconstruct how fast and where the groundwater was moving over the last 5 decades. Once the model simulations were able to match the concentrations that were measured, additional complexity was added to the model in order to simulate how arsenic was mobilised and transported in the Holocene aquifer.At the study site, changes in groundwater flow occurred over the past 50 years since the city of Hanoi markedly increased the extraction of groundwater to satisfy its steadily increasing water demand; this showed to be the main trigger for arsenic pollution in the aquifer. The computer modelling allowed the researchers to pinpoint the source of arsenic down to the river muds that are regularly deposited at the more slow-flowing zones of the Red River. The organic matter contained in those muds fuelled a biogeochemical reaction that led to the release of arsenic and its km-long transport into the aquifer underlying the Van Phuc village, a process that continues to this day. Employing their developed computer model in predictive mode the researchers were able to illustrate the interplay of four key factors on the evolution and longevity of arsenic release at surface water/groundwater interfaces, (i) the abundance of reactive organic matter; (ii) the abundance of iron oxides; (iii) the magnitude of groundwater flow; and (iv) river mud deposition rate.

Pollution

April 7, 2020

https://www.sciencedaily.com/releases/2020/04/200407072722.htm

Litter problem at England's protected coasts

Beaches in or near England's Marine Protected Areas (MPAs) have the same levels of litter as those in unprotected areas, new research shows.

The study, by the University of Exeter, Natural England and the Marine Conservation Society, found "no difference" in the amount of anthropogenic (caused by humans) litter present inside and outside MPAs.These MPAs include the 91 Marine Conservation Zones established from 2009 onwards, 256 Special Areas of Conservation (SACs) and 89 Special Protection Areas (for birds).Plastic was the main form of litter found, and "public littering" the most common identifiable source.The study, which used data from Marine Conservation Society beach cleans, found MPAs in the South East (Kent) and South West (Cornwall and Devon) had the highest levels of shore-based litter.Regional differences in the items found -- such as fishing materials in the South West and debris from sewage around large rivers -- demonstrate the need for "locally appropriate management," the researchers say."Our work has found that MPAs, which often contain sensitive marine habitats and species, are exposed to litter much in the same way as non-protected sites," said Dr Sarah Nelms, of the University of Exeter."MPAs have no physical boundaries so, to protect them from any potential impacts of litter, we need to take a whole-system approach and reduce the overall amount of litter being released into the environment."We also need a coordinated approach that considers local nuances, tackling sources of litter that cause specific problems in certain areas."The study used 25 years of beach clean data collected by Marine Conservation Society volunteers.Dr Hazel Selley, Marine Specialist from Natural England who commissioned the work, said: "A clean, healthy and biologically diverse marine environment is immensely valuable, for the economy in coastal communities, for our charismatic wildlife and -- once we can travel again -- for the mental well-being benefits of spending time by the sea."This research sheds a light on how marine plastic pollution respects no boundaries."As we continue to research the impact of plastics on our marine life and move to eliminate avoidable plastic waste, it's also clear is that we all have a role to play keeping our beaches and ocean clean."Lauren Eyles, from the Marine Conservation Society, said: "The types of litter that were found are typical of those regularly picked up and recorded by our dedicated volunteers."What this study highlights is how long-term data from Beachwatch can provide vital evidence in helping to understand the problem, and that MPAs don't necessarily protect important habitats and species; an even more powerful message to stop litter at source."

Pollution

April 6, 2020

https://www.sciencedaily.com/releases/2020/04/200406190529.htm

Scientists' warning to humanity on insect extinctions

Some of the tiniest creatures on the planet are vital for the environment. But there is a worldwide fall in insect numbers after an accelerating rate of extinction.

Now, a global group of 30 scientists -- including University of Huddersfield lecturer Dr Matt Hill -- has highlighted the issue and suggests practical steps that everyone can take to help halt the decline. These include mowing lawns less often, avoiding pesticides and leaving old trees, stumps and dead leaves alone.A specialist in aquatic environments, Dr Hill teaches on the University's recently-established geography degree course and supervises students as they take part in conservation projects.Pollution and human impact on habitats mean that insects such as beetles, dragonflies and mayflies plus other macroinvertebrates such as snails are in long-term decline across the world, in the UK as much as anywhere, said Dr Hill. Yet they make a vital contribution to the environment."They provide food for other animals and they can also have a significant role in the functioning of freshwater ecosystems, forming a critical component in the diversity of life," he added.Dr Hill was sought out to work with scientists in countries that include Germany, the UK, Columbia, Finland and South Africa. They pooled their research into insect decline and collaborated on the two new articles.These tell how factors such as climate change, the loss of habitats and pollution -- including harmful agricultural practices -- have all contributed to declines in insect population and to species extinctions.Insects have many functions in the ecosystem that cannot be replicated by technology or any other innovation. For example, the need for pollination means that crops depend on insects to survive, and their decomposition means they contribute to nutrient cycling.The team behind the research and the new articles have drawn up a nine-point plan that enables individuals to contribute to insect survival:2. Plant native plants; many insects need only these to survive3. Avoid pesticides; go organic, at least for your own backyard4. Leave old trees, stumps and dead leaves alone; they are home to countless species5. Build an insect hotel with small horizontal holes that can become their nests6. Reduce your carbon footprint; this affects insects as much as other organisms7. Support and volunteer in conservation organisations8. Do not import or release living animals or plants into the wild that could harm native species9. Be more aware of tiny creatures; always look on the small side of life.Dr Hill specialises in aquatic habitats and his areas of research include pondscapes -- including garden ponds -- and freshwater in urban areas. He teaches modules that include ecological theory and practical conservation. Students take part in field trips that include sampling of macroinvertebrates in rivers and in their second year they conduct an in-depth study of the impact of urbanisation.

Pollution

April 6, 2020

https://www.sciencedaily.com/releases/2020/04/200406100824.htm

Link between air pollution and coronavirus mortality in Italy could be possible

The world has been hit hard by coronavirus, and health services and authorities everywhere are struggling to reduce the spread, combat the disease and protect the population. Nevertheless, the pandemic will cost lives throughout the world. An environmental researcher from Aarhus University has studied whether there could be a link between the high mortality rate seen in northern Italy, and the level of air pollution in the same region. The short answer is "yes possibly." The long answer is in the article below.

The outbreak of Severe Acute Respiratory Syndrome CoronaVirus2 had its source in the Wuhan Province in China in December 2019. Since then, the coronavirus has spread to the rest of the globe, and the world is now treating patients with the disease that follows virus infection: COVID-19. The course of the disease differs for patients the world over: many experience flu-like symptoms, while many others need hospital treatment for acute respiratory infection that, in some cases, leads to death.However, what factors affect the course of the disease and the possibilities to combat COVID-19 remains unclear, as long as there is no medical treatment or vaccine. At the moment, there are more questions than answers, and researchers all over the world are therefore working to find new insights into the global pandemic.At Aarhus University, the environmental scientist Dario Caro from the Department of Environmental Science, and two health researchers, prof. Bruno Frediani and Dr. Edoardo Conticini, from the University of Siena in Italy have found yet another small piece in the puzzle of understanding the deadly disease. They have focused on examining why the mortality rate is up to 12% in the northern part of Italy, while it is only approx. 4.5% in the rest of the country.They have just published an article entitled "Can Atmospheric pollution be considered as a co-factor in the extremely high level of SARS-CoV-2 lethality in Northern Italy?," in which they demonstrate a probable correlation between air pollution and mortality in two of the worst affected regions in northern Italy: Lombardy and Emilia Romagna.The research project has been published in the scientific journal "There are several factors affecting the course of patients' illness, and all over the world we're finding links and explanations of what is important. It's very important to stress that our results are not a counter-argument to the findings already made. At the moment, all new knowledge is valuable for science and the authorities, and I consider our work as a supplement to the pool of knowledge about the factors that are important for the course of patients' illness," says environmental scientist Dario Caro, and clarifies that there are a number of other factors that could possibly play a role in the Italian situation:"Our considerations must not let us neglect other factors responsible of the high lethality recorded: important co-factors such as the elevated medium age of the Italian population, the wide differences among Italian regional health systems, ICUs capacity and how the infects and deaths has been reported have had a paramount role in the lethality of SARS-CoV-2, presumably also more than pollution itself," he explains.The two northern Italian regions are among the most air-polluted regions in Europe. The recently published article took its outset in data from the NASA Aura satellite, which has demonstrated very high levels of air pollution across precisely these two regions. The group compared these data with the so-called Air Quality Index; a measurement of air quality developed by the European Environment Agency. The index gathers data from several thousand measuring stations all over Europe, providing a geographical insight into the prevalence of a number of pollutant sources in the EU.The figures speak for themselves. The population of the northern Italian regions lives in a higher level of air pollution, and this may lead to a number of complications for patients with COVID-19 in the regions, simply because their bodies may have already been weakened by the accumulated exposure to air pollution when they contract the disease.Dario Caro explains that the situation in the Italian regions has been a challenge for several years, with high levels of air pollution that have accumulated over a long period of time in the population. It is therefore unlikely that there is any reason to imagine that people in Denmark are exposed to the same factors or the same levels of pollution as people in northern Italy, where the authorities have been trying to reduce pollution levels for many years."All over the world, we're seeing different approaches from countries' authorities, in countries' general public health outset and in the standards and readiness of different countries' national healthcare systems. But this doesn't explain the prevalence and mortality rates that we're seeing in northern Italy compared with the rest of Italy. This feeds hope that we may have found yet another factor in understanding the high mortality rate of the disease in northern Italy," says Dario Caro.

Pollution

April 3, 2020

https://www.sciencedaily.com/releases/2020/04/200403132347.htm

Removing the novel coronavirus from the water cycle

Scientists know that coronaviruses, including the SARS-CoV-2 virus responsible for the COVID-19 pandemic, can remain infectious for days -- or even longer -- in sewage and drinking water.

Two researchers, Haizhou Liu, an associate professor of chemical and environmental engineering at the University of California, Riverside; and Professor Vincenzo Naddeo, director of the Sanitary Environmental Engineering Division at the University of Salerno, have called for more testing to determine whether water treatment methods are effective in killing SARS-CoV-2 and coronaviruses in general.The virus can be transported in microscopic water droplets, or aerosols, which enter the air through evaporation or spray, the researchers wrote in an editorial for "The ongoing COVID-19 pandemic highlights the urgent need for a careful evaluation of the fate and control of this contagious virus in the environment," Liu said. "Environmental engineers like us are well positioned to apply our expertise to address these needs with international collaborations to protect public health."During a 2003 SARS outbreak in Hong Kong, a sewage leak caused a cluster of cases through aerosolization. Though no known cases of COVID-19 have been caused by sewage leaks, the novel coronavirus is closely related to the one that causes SARS, and infection via this route could be possible.The novel coronavirus could also colonize biofilms that line drinking water systems, making showerheads a possible source of aerosolized transmission. This transmission pathway is thought to be a major source of exposure to the bacteria that causes Legionnaire's disease, for example.Fortunately, most water treatment routines are thought to kill or remove coronaviruses effectively in both drinking and wastewater. Oxidation with hypochlorous acid or peracetic acid, and inactivation by ultraviolet irradiation, as well as chlorine, are thought to kill coronaviruses. In wastewater treatment plants that use membrane bioreactors, the synergistic effects of beneficial microorganisms and the physical separation of suspended solids filter out viruses concentrated in the sewage sludge.Liu and Naddeo caution, however, that most of these methods have not been studied for effectiveness specifically on SARS-CoV-2 and other coronaviruses, and they have called for additional research.They also suggest upgrading existing water and wastewater treatment infrastructure in outbreak hot spots, which possibly receive coronavirus from places such as hospitals, community clinics, and nursing homes. For example, energy-efficient, light-emitting, diode-based, ultraviolet point-of-use systems could disinfect water before it enters the public treatment system.Potable water-reuse systems, which purify wastewater back into tap water, also need thorough investigation for coronavirus removal, and possibly new regulatory standards for disinfection, the researchers wrote.The extent to which viruses can colonize biofilms is also not yet known. Biofilms are thin, slimy bacterial growths that line the pipes of many aging drinking water systems. Better monitoring of coronaviruses in biofilms might be necessary to prevent outbreaks.The surge in household use of bactericides, virucides and disinfectants will probably cause an increase of antibiotic-resistant bacteria in the environment. Treated wastewater discharged into natural waterways demands careful monitoring through the entire water cycle. Liu and Naddeo call on chemists, environmental engineers, microbiologists, and public health specialists to develop multidisciplinary and practical solutions for safe drinking water and healthy aquatic environments.Lastly, developing countries and some regions within highly developed nations, such as rural and impoverished communities, which lack the basic infrastructure to remove other common contaminants might not be able to remove SARS-CoV-2 either. These places might experience frequent COVID-19 outbreaks that spread easily through globalized trade and travel. Liu and Naddeo suggest governments of developed countries must support and finance water and sanitation systems wherever they are needed."It is now clear to all that globalization also introduces new health risks. Where water and sanitation systems are not adequate, the risk of finding novel viruses is very high," Naddeo said. "In a responsible and ideal scenario, the governments of developed countries must support and finance water and sanitation systems in developing countries, in order to also protect the citizens of their own countries."

Pollution

April 3, 2020

https://www.sciencedaily.com/releases/2020/04/200403082851.htm

Coastal pollution reduces genetic diversity of corals, reef resilience

A new study by researchers at the University of Hawai'i at M?noa School of Ocean and Earth Science and Technology (SOEST) found that human-induced environmental stressors have a large effect on the genetic composition of coral reef populations in Hawai'i. They confirmed that there is an ongoing loss of sensitive genotypes in nearshore coral populations due to stressors resulting from poor land-use practices and coastal pollution. This reduced genetic diversity compromises reef resilience.

The study identified closer genetic relationships between nearshore corals in Maunalua Bay, Oahu and those from sites on West Maui, than to corals from the same islands, but further offshore. This pattern can be described as isolation by environment in contrast to isolation by distance. This is an adaptive response by the corals to watershed discharges that contain sediment and pollutants from land."While the results were not surprising, they clearly demonstrate the critical need to control local sources of stress immediately while concurrently addressing the root causes of global climate change," said Robert Richmond, research professor and director of the Kewalo Marine Laboratory and co-author of the study. "Additionally, this innovative science shows the need to track biodiversity at multiple levels."This research provides valuable information to coral reef managers in Hawai'i and around the world who are developing approaches and implementation plans to enhance coral reef resilience and recovery through reef restoration and stressor reduction."This study shows the value of applying molecular tools to ecological studies supporting coral reef management," stated Kaho Tisthammer, lead researcher on this paper.While the loss of coral colonies and species is easy to see with the naked eye, molecular tools are needed to uncover the effects of stressors on the genetic diversity within coral reef populations.

Pollution

April 2, 2020

https://www.sciencedaily.com/releases/2020/04/200402100900.htm

A friendlier way to deal with nitrate pollution

Learning from nature, scientists from the Center for Sustainable Resource Science in Japan and the Korean Basic Science Institute (KBSI) have found a catalyst that efficiently transforms nitrate into nitrite -- an environmentally important reaction -- without requiring high temperature or acidity, and now have identified the mechanism that makes this efficiency possible. Nitrogen is an important element for various biological processes, but it is often necessary to convert it into one form or another, in a system known as the nitrogen cycle. In nature, this is usually carried out by bacteria and other microorganisms, which can perform the feat at ambient temperature and mild pH conditions. Recently, the excessive use of nitrogen fertilizers in response to population growth has led to serious water pollution due to the presence of nitrate (NO3-) ions in fertilizers. Runoff from agriculture can lead to nitrate pollution of drinking water, and the eutrophication of lakes and marshes, leading to algae growth. As a result, it has become necessary to reduce the emission of nitrate ions into the environment.

Wastewater cleaning using microbes is currently performed, but it is not always possible to do this, as the concentration of nitrate can make it impossible for microorganisms to survive. There have been attempts to create catalysts that can perform the same task done by bacteria. Unfortunately, due to the high stability of nitrate, these expensive rare metal catalysts require high temperature, ultraviolet photolysis, or strongly acidic environments. Thus the development of catalysts that could cheaply perform the transformation at ambient temperatures was a major goal of research.Recently, an international team led by Ryuhei Nakamura of the RIKEN Center for Sustainable Resource Science (CSRS), decided to try to use the same method as nitrate reductase, an enzyme used by microorganisms, and succeeded in chemically synthesizing oxo-containing molybdenum sulfide, which was able to catalyze nitrate into nitrite in an aqueous electrolyte at neutral pH.Now, in research published in Their main finding was that pentavalent molybdenum with oxygen ligands -- one of the intermediate products -- functioned as an active species that accelerated the reaction, and showed that this active species has a structure similar to the active core of natural nitrate reductase. Their studies using EPR spectroscopy confirmed this, finding that the oxygen and sulfur, ligands of the molybdenum also play an important role in efficiently producing the pentavalent oxo-molybdenum species on the catalyst surface.According to Nakamura, "This result shows that nitrate ions can be detoxified in a mild environment without depending on rare metal catalysts. We hope that this will make possible the development of new technology for synthesizing ammonia from waste liquid."

Pollution

April 2, 2020

https://www.sciencedaily.com/releases/2020/04/200402100858.htm

Our oceans are suffering, but we can rebuild marine life

It's not too late to rescue global marine life, according to a study outlining the steps needed for marine ecosystems to recover from damage by 2050.

University of Queensland scientist Professor Catherine Lovelock said the study found many components of marine ecosystems could be rebuilt if we try harder to address the causes of their decline."People depend on the oceans and coastal ecosystems as a source of food, livelihoods, carbon capture and, thanks to coral reefs, mangroves and other coastal ecosystems, for protection from storms," Professor Lovelock said."But people are having enormous impacts globally and it's time to do what we must to ensure our oceans are healthy and vibrant for generations to come."The research revealed many examples of recovery of marine populations, habitats and ecosystems following conservation interventions."Despite humanity having greatly distorted our oceans, recent interventions have led to a number of remarkable success stories," Professor Lovelock said."The world has come together before to implement moratoriums on whaling, create a Law of the Sea, prevent pollution from ships, and limit industrialised fishing -- all with positive outcomes."For the sake of our oceans, let's go further."The main issue we need to tackle is climate change and we can only rebuild the abundance of the world's marine if the most ambitious goals within the Paris Agreement are reached."Professor Lovelock said the benefits of strong action are myriad."Conserving coastal wetlands could improve food security for the millions of people who depend on them, and reduce the dangers of storm damage and flooding -- saving billions of dollars," she said."Mangroves, saltmarshes and seagrasses can store carbon in their soils and biomass which can help mitigate climate change."They provide so many benefits to coastal society that investing to rebuild them is a no-brainer."Professor Carlos Duarte from Saudi Arabia's King Abdullah University of Science and Technology said the goal was not to recreate historical ecosystems."That's no longer possible -- rather we should improve on the status quo by re-building stocks of depleted marine populations over coming decades," Professor Duarte said."The elephant in the room is climate change, especially for vulnerable ecosystems like coral reefs and kelp beds."There's no one silver bullet -- we have to address the root causes of ecological collapses."It's not enough to reduce pollution or fishing pressure as the future of the ocean also depends on how rapidly greenhouse gas emissions are reduced."

Pollution

April 1, 2020

https://www.sciencedaily.com/releases/2020/04/200401111651.htm

The candy-cola soda geyser experiment, at different altitudes

Dropping Mentos

During production, soda is carbonated by sealing it under carbon dioxide pressure that is about four times the total air pressure. This causes carbon dioxide to dissolve in the beverage. When someone opens the container, carbon dioxide escapes from the space above the liquid, and the dissolved carbon dioxide slowly enters the gas phase, eventually causing the soda to go "flat." MentosIn the lab, the researchers added a Mentos

Pollution

March 30, 2020

https://www.sciencedaily.com/releases/2020/03/200330110342.htm

Air pollution linked to dementia and cardiovascular disease

People continuously exposed to air pollution are at increased risk of dementia, especially if they also suffer from cardiovascular diseases, according to a study at Karolinska Institutet in Sweden published in the journal

The number of people living with dementia is projected to triple in the next 30 years. No curative treatment has been identified and the search for modifiable risk and protective factors remains a public health priority. Recent studies have linked both cardiovascular disease and air pollution to the development of dementia, but findings on the air pollution-link have been scarce and inconsistent.In this study, the researchers examined the link between long-term exposure to air pollution and dementia and what role cardiovascular diseases play in that association. Almost 3,000 adults with an average age of 74 and living in the Kungsholmen district in central Stockholm were followed for up to 11 years. Of those, 364 people developed dementia. The annual average level of particulate matter 2.5 microns or less in width (PM2.5) are considered low compared to international standards."Interestingly, we were able to establish harmful effects on human health at levels below current air pollution standards," says first author Giulia Grande, researcher at the Department of Neurobiology, Care Sciences and Society at Karolinska Institutet. "Our findings suggest air pollution does play a role in the development of dementia, and mainly through the intermediate step of cardiovascular disease and especially stroke."For the last five years of exposure, the risk of dementia increased by more than 50 percent per interquartile range (IQR) difference in mean PM2.5 levels and by 14 percent per IQR in nitrogen oxide. Earlier exposures seemed less important. Heart failure and ischemic heart disease both enhanced the dementia risk and stroke explained almost 50 percent of air pollution-related dementia cases, according to the researchers."Air pollution is an established risk factor for cardiovascular health and because CVD accelerates cognitive decline, we believe exposure to air pollution might negatively affect cognition indirectly," says Giulia Grande. "In our study, virtually all of the association of air pollution with dementia seemed to be through the presence or the development of CVD, adding more reason to reduce emissions and optimize treatment of concurrent CVD and related risk factors, particularly for people living in the most polluted areas of our cities.

Pollution

March 30, 2020

https://www.sciencedaily.com/releases/2020/03/200330093429.htm

Extreme, high temperatures may double or triple heart-related deaths

When temperatures reach extremes of an average daily temperature of 109 degrees Fahrenheit, the number of deaths from cardiovascular disease may double or triple. Researchers note that these findings raise concerns that traditionally hot regions may be especially vulnerable to heat-related cardiovascular deaths, according to new research published today in

The highest temperature on earth in the last 76 years, 129 degrees Fahrenheit, was recently recorded in Kuwait. Given the consistently high temperatures in Kuwait (average ambient temperature 82.2 degrees Fahrenheit), researchers examined the relationship between temperature and more than 15,000 cardiovascular-related deaths in the country. All death certificates in Kuwait from 2010 to 2016 that cited "any cardiovascular cause" for individuals ages 15 and older were reviewed for this study.Compared to the number of deaths on days with the lowest mortality temperature (average daily temperature of 94.5 degrees Fahrenheit, when the fewest people died), when the 24-hour average temperature was extreme (109 degrees Fahrenheit or higher), the investigators found:To examine the effects of temperature on its own, the investigators adjusted for other environmental factors such as air pollution and humidity. Higher temperatures affected both genders and all ages differently."While cardiologists and other medical doctors have rightly focused on traditional risk factors, such as diet, blood pressure and tobacco use, climate change may exacerbate the burden of cardiovascular mortality, especially in very hot regions of the world," said Barrak Alahmad, When core body temperature increases, the human body tries to cool itself by shifting blood from the organs to underneath the skin. This shift causes the heart to pump more blood, putting it under significantly more stress. A collaborative group of cardiologists, environmental health specialists and epidemiologists hypothesized that increasing temperatures in hotter regions of the world could lead to increased CVD death due to extreme heat's effects on the body."The warming of our planet is not evenly distributed. Regions that are inherently hot, like Kuwait and the Arabian Peninsula, are witnessing soaring temperatures unlike ever before. We are sounding the alarm that populations in this part of the world could be at higher risk of dying from cardiovascular causes due to heat," said Alahmad. "Although we cannot conclude it from this analysis, men and working-age people may have been at greater increased risk because of spending more time outside. We need to explore this relationship further and consider serious preventive strategies that could reduce the impact of rising temperatures on our health."The study was limited by only having information on any cardiovascular cause of death, so it is not known whether any specific type of heart problem is more susceptible to the influence of extreme heat. Although the researchers found a strong association between extremely high temperatures and increased cardiovascular deaths, further research is needed to establish a cause and effect relationship.

Pollution

March 27, 2020

https://www.sciencedaily.com/releases/2020/03/200327141517.htm

Seafloor of Fram Strait is a sink for microplastic from Arctic and North Atlantic Ocean

Working in the Arctic Fram Strait, scientists from the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research (AWI) have found microplastic throughout the water column with particularly high concentrations at the ocean floor. Using model-based simulations, they have also found an explanation for this high level of pollution. According to their findings, the two main ocean currents in Fram Strait transport the microscopically small plastic particles into the region between Greenland and Spitsbergen from both the Arctic and the North Atlantic. While passing through the Strait, many particles eventually drift to the seafloor, where they accumulate. The experts report on this phenomenon in a study just released in the journal

Located between the northeast coast of Greenland and the Svalbard archipelago, Fram Strait is the only deep passage between the Arctic and Atlantic Oceans. In its waters, which reach depths of 5,600 metres, two opposing currents flow right by one another like an underwater highway. In the eastern "lane" the West Spitsbergen Current transports warm water north from the Atlantic, while in the other lane the East Greenland Current moves sea ice and frigid water south from the Arctic. This extraordinary combination of circumstances is most likely the reason why experts from the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research while collecting water and seafloor samples at the Arctic deep-sea observatory HAUSGARTEN in Fram Strait, detected extremely high quantities of microplastic particles in the sediment, and intermediate levels in the water column in the summer of 2016."We found the highest concentration of microplastic particles in water at our northernmost sampling spot near the sea-ice edge," reports AWI biologist and first author Mine Tekman. In the area technically referred to as the marginal ice zone, one cubic metre of surface water contained more than 1,200 microplastic particles, though this hardly came as a surprise to the researchers. "From previous studies we knew that the Arctic sea ice can contain as much as 12,000 microplastic particles per litre of meltwater. When this ice reaches the end of its journey and melts in the northern Fram Strait, it most likely releases its microplastic load into the sea, which would explain the high concentration in the surface waters," she adds.In contrast, the level of pollution was 16,000 times higher in sediments at the bottom of Fram Strait. The analysis of sediment samples with a Fourier-transform infrared spectrometer (FTIR) revealed up to 13,000 microplastic particles per kilogramme of sediment. "This large quantity of particles and the various types of plastic we found in the sediment confirm that microplastic is continually accumulating on the seafloor of Fram Strait. In other words, the deep sea in this region is a sink for microscopically small plastic particles," says AWI deep-sea expert and co-author Dr Melanie Bergmann.This view was confirmed by ocean circulation modelling, in which the experts simulated the microplastic particles' route to Fram Strait. Depending on the particle size, type of plastic, sinking speed and water depth, some particles travelled up to 650 kilometres before coming to rest on the ocean floor. "The results of our model disprove the notion that microplastic particles could rapidly and almost vertically sink to the bottom," says Melanie Bergmann. In fact, the plastic waste is caught by the ocean currents and can drift for tremendous distances. Especially the aggregation with organic material like algal remains is what causes the particles to sink from the surface through the water column to the seafloor.With regard to Fram Strait, this means the majority of the plastic particles stockpiled at its bottom likely originate from remote regions; for instance, the East Greenland Current transports microplastic from the Arctic Ocean to the eastern Greenland slope. While collecting samples in its basin, the researchers above all found ethylene-vinyl acetate, a type of plastic used e.g. for coatings, lacquers, paper, packaging and shoe soles. In contrast, the West Spitsbergen Current carries particles from waters south of Spitsbergen into Fram Strait. This finding was also reflected in the plastic mix found in the respective samples.It should also be mentioned that more than half of all plastic particles identified were smaller than 25 micrometres in diameter, roughly half the thickness of a fine human hair. "This high percentage of truly minute particles is of course troubling, as it immediately raises the question of how marine organisms respond to these minuscule bits of plastic waste," says Melanie Bergmann. To answer this question, British colleagues are currently investigating whether the crustaceans in the AWI's Arctic zooplankton samples have consumed any plastic.For their part, the AWI experts now want to explore how the microplastic levels in Fram Strait change throughout the year. To this end, they'll use devices referred to as sediment traps, which are moored at the AWI's Arctic deep-sea observatory HAUSGARTEN and catch the various particles and marine snow that gradually descend from the sea surface, all through the year."The study that's just been released offers an important snapshot in which analyses with infrared microscopes allowed us to gain a solid overview of plastic pollution in Fram Strait," says Gunnar Gerdts, an AWI microbiologist and Head of the Microplastic Analysis Group. The experts determined that 39 percent of the particles suspended in the water came from polyamide, which is used to produce e.g. fibres for textiles and fishing nets, while nearly a quarter of all particles in the water column were identified as synthetic rubber (ethylene-propylene-diene rubber), an elastic type of plastic used e.g. in automotive and machine-building, as pond liner, for sealing roofs and house fronts, and as filler in artificial turf. In the seafloor sediments, the team primarily found particles made of chlorinated polyethylene (CPE), which is used e.g. in the manufacture of cables, hoses, films and antilock braking systems (ABS).

Pollution

March 27, 2020

https://www.sciencedaily.com/releases/2020/03/200327113702.htm

Scientists predict the size of plastics animals can eat

A team of scientists at Cardiff University has, for the first time, developed a way of predicting the size of plastics different animals are likely to ingest.

The researchers, from the University's Water Research Institute, looked at the gut contents of more than 2,000 animals to create a simple equation to predict the size of a plastic item an animal can eat, based on the length of its body.In the study, published today in The researchers say that as the plastic pollution problem escalates, it is vital to be able to quickly assess the risk of plastics to different species around the world.This work could also help scientists measure the risk of plastic pollution to ecosystems and food supplies -- and ultimately the risk to human health.By trawling through published data, the team found plastics ingested by marine and freshwater mammals, reptiles, fishes and invertebrates, from 9mm-long fish larvae to a 10m-long humpback whale.During their research they found some shocking examples of the extent of plastic pollution, including hosepipes and flower pots in a sperm whale, plastic banana bags inside green turtles and a shotgun cartridge in a True's beaked whale.Co-lead author of the study Dr Ifan Jâms said: "We still know very little about the way most animals feed in the wild, so it's difficult to figure out how much plastic they could be eating."This information gives us a way to start measuring the extent of the plastic pollution problem."We hope this study lays a foundation for including the 'ingestibility' of plastics into global risk assessments."We also hope this work will encourage more sophisticated assessments of the amount of plastic that may be moving into global ecosystems and food supplies."Project leader Professor Isabelle Durance said: "All of us will have seen distressing, often heart-breaking, images of animals affected by plastic, but a great many more interactions between animals and plastic are never witnessed. This study gives us a new way of visualising those many, many unseen events."While we understand increasingly where concentrations of plastic in the world's aquatic ecosystems are greatest, it's only through work like this that we can know which animals are likely to be in danger from ingesting it."Through this work, we can also begin to understand how much plastic is entering global food webs or human foods, for example, because we know the general sizes of plastic likely to be taken in by zooplankton or fishes."We recognise that our research is part of wider efforts and there is still more work to do to quantify the risks from smaller plastic fragments or to understand the damage caused by plastic ingestion, but we hope this work helps the world to address its growing plastic problem."The researchers said further work was needed to look at how and where terrestrial animals eat plastic to predict wider risks.

Pollution

March 27, 2020

https://www.sciencedaily.com/releases/2020/03/200327103034.htm

Control of anthropogenic atmospheric emissions can improve water quality in seas

A new research led by MPhil student Miss Yu Yan Yau and supervised by Dr Benoit Thibodeau from the Department of Earth Sciences and the Swire Institute of Marine Science, the University of Hong Kong (HKU), highlighted the importance of reducing fossil fuel combustion not only to curb the trend of global warming, but also to improve the quality of China's coastal waters. The findings were recently published in the  journal

Fossil fuel burning is strongly associated with global warming. However, atmospheric and marine pollution linked to energy production, transportation and industrial activity are often overlooked. Production of nitrogen oxides (NOx) emissions via fossil fuel burning and the manufacturing of fertilizer pollutes the atmosphere and leads to the formation of ground-level ozone, smog, acid rain and contributes to global warming through the greenhouse effect. Moreover, nitrogen is a natural fertilizer and thus when atmospheric nitrogen oxides deposit in the water, it can also have a fertilizing effect. This fertilizing effect can lead to 'eutrophication'; a chain reaction starting with the addition of nutrients (here nitrogen oxides), which enhance the production of algae, which, in turn, die and sink to the bottom of the ocean and decompose. During the decomposition of this organic material, oxygen is consumed from the water, lowering the dissolved oxygen content at the bottom of the ocean. Constant reductions of dissolved oxygen scan lead to hypoxia, a level of oxygenation that is too low for most organisms to sustain their normal activities.The study used Intergovernmental Panel on Climate Change (IPCC) -- projected trends in atmospheric emissions of NOx coupled with a biogeochemical model to estimate the impact of the deposition of nitrogen oxides in four major Chinese coastal seas: The South China Sea, the East China Sea, the Yellow Sea and the Bohai Sea. The researchers found that although atmospheric deposition is not as important as riverine nitrogen input, it can still fuel up to 15% of the total amount of organic matter found at the bottom of the ocean, increasing significantly (up to 5%) the area of hypoxia. The good news is that it also found that a reduction of emissions can lead to a significant decrease of hypoxic zones, and that the South China Sea is the most sensitive area to nitrogen input."I hope our study brings more attention to the potential benefit of reducing fossil fuel burning on human and ecosystem health but also on local economic activities like fisheries, which are severely affected by hypoxia," said Miss Yau."Low levels of oxygen are observed in many coastal seas around the world and it is important to find better ways to tackle this problem. While we understand that sewage and nutrient input from the Pearl River drive most of the hypoxia in the Greater Bay Area, we observe low levels of oxygen in regions that are not directly under the influence of these sources. Thus, it is important to investigate the impact of atmospheric deposition more locally," Dr Thibodeau remarked.

Pollution

March 26, 2020

https://www.sciencedaily.com/releases/2020/03/200326080838.htm

New framework will help decide which trees are best in the fight against air pollution

A study from the University of Surrey has provided a comprehensive guide on which tree species are best for combatting air pollution that originates from our roads -- along with suggestions for how to plant these green barriers to get the best results.

In a paper published in As part of their critical review, the authors identified a gap in information to help people -- including urban planners, landscape architects and garden designers -- make informed decisions on which species of vegetation to use and, crucially, what factors to consider when designing a green barrier.To address this knowledge gap, they identified 12 influential traits for 61 tree species that make them potentially effective barriers against pollution. Beneficial plant properties include small leaf size, high foliage density, long in-leaf periods (e.g. evergreen or semi-evergreen), and micro-characteristics such as leaf hairiness. Generally detrimental aspects of plants for air quality include wind pollination and biogenic volatile organic compound emissions. In the paper, the team emphasise that the effectiveness of a plant is determined by its environmental context -- whether, for example, it will be used in a deep (typical of a city commercial centre) or shallow (typical of a residential road) street canyon or in an open road environment. To help concerned citizens with complex decisions, such as which tree is best for a road outside a school in a medium-sized street canyon, the team from Surrey has also developed a plant selection framework.Professor Prashant Kumar, Founding Director of GCARE at the University of Surrey, said: "We are all waking up to the fact that air pollution and its impact on human health and the health of our planet is the defining issue of our time. Air pollution is responsible for one in every nine deaths each year and this could be intensified by projected population growth."The use of green infrastructure as physical barriers between ourselves and pollutants originating from our roads is one promising way we can protect ourselves from the devastating impact of air pollution. We hope that our detailed guide to vegetation species selection and our contextual advice on how to plant and use green infrastructure is helpful to everyone looking to explore this option for combatting pollution."

Pollution

March 25, 2020

https://www.sciencedaily.com/releases/2020/03/200325110906.htm

Burying or burning garbage boosts airborne bacteria, antibiotic resistance genes

Municipal solid waste is trash -- such as plastic, food scraps and lawn clippings -- that goes into garbage bins and doesn't get recycled. Most of this waste is buried in landfills or is incinerated. Now, researchers reporting in ACS'

Residual antibiotics from discarded medications and other products can end up in municipal solid waste. Some microbes in the garbage are resistant to those antibiotics, and they can spread resistance genes to other bacteria, allowing them to survive in the presence of these drugs. But scientists hadn't studied whether treating the garbage through incineration or landfilling releases these bacteria and genes into the air, where people or animals could breathe them in. So Yi Luo, Xiangdong Li and colleagues wanted to investigate the bacterial community and associated antibiotic-resistance genes in the municipal solid waste treatment system of Changzhou, a city in eastern China.The researchers collected air samples surrounding a landfill site, a municipal solid waste incinerator and two transfer stations (where garbage is delivered and processed). Air from both the municipal incinerator and the landfill site had higher levels of particulate matter and bacteria than upwind locations. The team identified 16 antibiotic-resistance genes in the air samples and tracked their source to municipal solid waste and leachate in the system. The genes were much more abundant in air downwind from the facilities than upwind. These results suggest that municipal solid waste treatment systems could be a reservoir of antibiotic-resistance genes that can be transmitted to nearby residents who breathe the air, the researchers say.

Pollution

March 24, 2020

https://www.sciencedaily.com/releases/2020/03/200324102705.htm

Ships' emissions create measurable regional change in clouds

A container ship leaves a trail of white clouds in its wake that can linger in the air for hours. This puffy line is not just exhaust from the engine, but a change in the clouds that's caused by small airborne particles of pollution.

New research led by the University of Washington is the first to measure this phenomenon's effect over years and at a regional scale. Satellite data over a shipping lane in the south Atlantic show that the ships modify clouds to block an additional 2 Watts of solar energy, on average, from reaching each square meter of ocean surface near the shipping lane.The result implies that globally, cloud changes caused by particles from all forms of industrial pollution block 1 Watt of solar energy per square meter of Earth's surface, masking almost a third of the present-day warming from greenhouse gases. The open-access study was published March 24 in "In climate models, if you simulate the world with sulfur emissions from shipping, and you simulate the world without these emissions, there is a pretty sizable cooling effect from changes in the model clouds due to shipping," said first author Michael Diamond, a UW doctoral student in atmospheric sciences. "But because there's so much natural variability it's been hard to see this effect in observations of the real world."The new study uses observations from 2003 to 2015 in spring, the cloudiest season, over the shipping route between Europe and South Africa. This path is also part of a popular open-ocean shipping route between Europe and Asia.Small particles in exhaust from burning fossil fuels creates "seeds" on which water vapor in the air can condense into cloud droplets. More particles of airborne sulfate or other material leads to clouds with more small droplets, compared to the same amount of water condensed into fewer, bigger droplets. This makes the clouds brighter, or more reflective.Past attempts to measure this effect from ships had focused on places where the wind blows across the shipping lane, in order to compare the "clean" area upwind with the "polluted" area downstream. But in this study researchers focused on an area that had previously been excluded: a place where the wind blows along the shipping lane, keeping pollution concentrated in that small area.The study analyzed cloud properties detected over 12 years by the MODIS instrument on NASA satellites and the amount of reflected sunlight at the top of the atmosphere from the CERES group of satellite instruments. The authors compared cloud properties inside the shipping route with an estimate of what those cloud properties would have been in the absence of shipping based on statistics from nearby, unpolluted areas."The difference inside the shipping lane is small enough that we need about six years of data to confirm that it is real," said co-author Hannah Director, a UW doctoral student in statistics. "However, if this small change occurred worldwide, it would be enough to affect global temperatures."Once they could measure the ship emissions' effect on solar radiation, the researchers used that number to estimate how much cloud brightening from all industrial pollution has affected the climate overall.Averaged globally, they found changes in low clouds due to pollution from all sources block 1 Watt per square meter of solar energy -- compared to the roughly 3 Watts per square meter trapped today by the greenhouse gases also emitted by industrial activities. In other words, without the cooling effect of pollution-seeded clouds, Earth might have already warmed by 1.5 degrees Celsius (2.7 F), a change that the Intergovernmental Panel on Climate Change projects would have significant societal impacts. (For comparison, today the Earth is estimated to have warmed by approximately 1 C (1.8 F) since the late 1800s.)"I think the biggest contribution of this study is our ability to generalize, to calculate a global assessment of the overall impact of sulfate pollution on low clouds," said co-author Rob Wood, a UW professor of atmospheric sciences.The results also have implications for one possible mechanism of deliberate climate intervention. They suggest that strategies to temporarily slow global warming by spraying salt particles to make low-level marine clouds more reflective, known as marine cloud brightening, might be effective. But they also imply these changes could take years to be easily observed."What this study doesn't tell us at all is: Is marine cloud brightening a good idea? Should we do it? There's a lot more research that needs to go into that, including from the social sciences and humanities," Diamond said. "It does tell us that these effects are possible -- and on a more cautionary note, that these effects might be difficult to confidently detect."

Pollution

March 23, 2020

https://www.sciencedaily.com/releases/2020/03/200323132416.htm

Concrete solutions that lower both emissions and air pollution

Sometimes, fixing one problem can create another.

Concrete production contributes 8 percent of global greenhouse gases, and demand continues to rise as populations and incomes grow. Yet some commonly discussed strategies to reduce the sector's global GHG emissions could, under some scenarios, increase local air pollution and related health damages, according to a study from the University of California, Davis.For the study, published today in the journal The scientists also compared several GHG-reduction strategies to determine which are most likely to lower both global emissions and local air pollution related to concrete production. They found that a variety of available methods could, together, reduce climate and health damage costs by 44 percent."There is a high emissions burden associated with the production of concrete because there is so much demand for it," said lead author Sabbie Miller, an assistant professor in the UC Davis Department of Civil and Environmental Engineering. "We clearly care a great deal about greenhouse gas emissions. But we haven't paid as much attention to health burdens, which are also are driven in large part by this demand."Among the most effective strategies include using cleaner-burning kiln fuel, more renewable energy and replacing a portion of the cement used in production with lower-carbon alternative materials.While carbon capture and storage technologies could reduce GHG emissions from concrete production by up to 28 percent, the study found it could actually increase human health impacts from air pollutants unless the technology itself is powered by clean energy. It's also not currently widely implementable."Air pollution and climate change problems are really intertwined when we talk about solutions," said co-author Frances Moore, an assistant professor with the UC Davis Department of Environmental Science and Policy. "This paper takes these two problems and their joint nature seriously. It shows how different solutions have different effects for global climate change and local air pollution, which may matter a lot for policymakers."Cement production is responsible for about half of the total climate (32 percent) and health (18 percent) damages of making concrete. That is followed by aggregate production, which is responsible for 34 percent of health damages and 4 percent in climate damages.Mixing concrete, or batching, contributes little to climate damages but represents 11 percent of health damages.To reduce these impacts, the authors evaluated eight GHG reduction strategies and presented the options in ways policymakers can consider for feasibility.Methods that can be readily implemented to reduce climate damages include:Amine scrubbing and calcium looping, which are forms of carbon capture storage, could reduce climate damage costs over 50 percent and 65 percent, respectively. They are not yet readily implementable but may become so in the future.Cleaner combusting kiln fuel shows the greatest co-benefit, with a 14 percent reduction in health damages -- four times as large as any other mitigation strategy for air quality benefits.The authors note that additional strategies and policies that reduce particulate matter emissions may reduce air pollution impacts more directly.Major concrete-producing communities include parts of the U.S., China, Brazil, India, Russia and other regions. While effectiveness of strategies varies by region, the study says that overall, a mixture of the strategies could reduce climate and health damages by 85 percent and 19 percent, respectively."As the cement and concrete industries make large efforts to reduce greenhouse gas emissions, it is critical that they remain mindful of the impacts decisions have on other environmental burdens to avoid undesired side effects," Miller said.

Pollution

March 23, 2020

https://www.sciencedaily.com/releases/2020/03/200323125603.htm

Coal exit benefits outweigh its costs

Coal combustion is not only the single most important source of CO

"We're well into the 21st century now and still heavily rely on burning coal, making it one of the biggest threats to our climate, our health and the environment. That's why we decided to comprehensively test the case for a global coal exit: Does it add up, economically speaking? The short answer is: Yes, by far," says Sebastian Rauner, lead author and researcher at the Potsdam Institute for Climate Impact Research (PIK). For their computer simulations, the researchers looked not only at electricity generation, but at all energy sectors, including transport, buildings, industry and agriculture."We find that, based on all countries' current climate pledges under the Paris Agreement, humanity is so far not on track to keep global warming below 2 degrees. Yet, if all countries would introduce coal exit policies, this would reduce the gap to fulfilling the goal by 50 percent worldwide. For coal-heavy economies like China and India, quitting coal would even close the gap by 80-90 percent until 2030."The researchers developed a simulation framework which considers the full life cycle effects of phasing out coal, accounting not only for all impacts along of coal combustion from shaft to chimney, but also how a coal exit would affect the remaining energy sources and the energy sector as a whole. For the first time, they analysed monetised environmental and human health costs, thus enabling a comparison with mitigation costs: "In particular, we looked at two externalities: Human health costs, especially caused by respiratory diseases, and biodiversity loss, as measured on the basis of how much it would cost to rewild areas currently cultivated. The mitigation costs, in turn, are mostly economic growth reductions and costs for investments in the energy system.""Benefits from reduced health and ecosystem impacts clearly overcompensate the direct economic costs of a coal exit -- they amount to a net saving effect of about 1.5 percent of global economic output in 2050 -- that is, 370$ for every human on Earth in 2050.," Gunnar Luderer explains, leader of the energy research group at PIK. "We see this effect already in the medium term. In particular, India and China could reap most of those benefits already by 2030."China and India are prime cases for a coal exit given their high reliance on coal and pressing air pollution crises, magnified by high population density, as well as population growth in India and an increasingly vulnerable aging population in China. Thus people could feel the positive effects of a coal exit almost immediately in their daily lives. "This has very significant policy implications: It makes a huge difference for the citizens of an Indian or Chinese megacity what air they breeze, and for farmers how intact ecosystems are. These benefits are immediate and local," says Sebastian Rauner. "So the incentives towards policy makers are twofold: One, it is not unlikely that phasing out coal can win popular support, and eventually elections. Two, it is worthwhile phasing out coal even if your neighbours do not.""Phasing out coal could hence be one way out of what we know as the tragedy of the commons," adds Nico Bauer, a co-author of the study and also at PIK, "Coal phase-out has a positive synergy between the global climate challenge and local environmental pollution. In international climate negotiations, governments need to factor-in that exiting coal is a cheap way to substantially reduce global greenhouse gas emissions and has huge co-benefits at home. Our study shows that national and global interests are not necessarily trading-off, but can go hand in hand."Given the Paris Agreement's current requirement for updates to the Nationally Determined Contributions (NDCs), this paper comes quite timely, comments co-author Gunnar Luderer of PIK: "It underscores the benefits of a global coal exit -- to the better of our planet and our health. Yet, importantly, ending coal is just the beginning. It must be flanked by further ambitious climate policies to avoid a lock-in to other fossil fuels, namely oil or natural gas."

Pollution

March 18, 2020

https://www.sciencedaily.com/releases/2020/03/200318104408.htm

Fish scales could make wearable electronics more sustainable

Flexible temporary electronic displays may one day make it possible to sport a glowing tattoo or check a reading, like that of a stopwatch, directly on the skin. In its current form, however, this technology generally depends on plastic. New research in

Within such displays, electricity-conducting and light-emitting components are layered onto a transparent film. To make them flexible enough to withstand the bending required to stay on skin or other soft surfaces, researchers have so far relied on films made of plastic -- a substance derived from fossil fuels, a limited resource and a source of pollution. Hai-Dong Yu, Juqing Liu, Wei Huang and colleagues wanted to find a more sustainable and environmentally friendly material for the film. They settled on gelatin derived from collagen in fish scales, which are usually thrown away.After preparing a gelatin solution from the fish scales, they poured it into a petri dish that acted as a mold for the film as it dried. In tests, they found the film had the attributes, including flexibility and transparency, needed for use in wearable devices. The film also appeared unlikely to linger in landfills: It dissolved within seconds in hot water and could then be recycled into a new film. When buried in soil, it degraded within 24 days. The team used the film to build a working alternating current electroluminescent device that continued to glow even after being bent and relaxed 1,000 times. Films derived from fish scales are a promising alternative for more sustainable flexible electronics, including wearables and folding displays, the researchers conclude.

Pollution

March 16, 2020

https://www.sciencedaily.com/releases/2020/03/200316173516.htm

Microplastic fibers linked to respiratory, reproductive changes in fish

Chronic exposure to microplastic fibers causes aneurysms, erosion of surface layers and other serious damage to fish gills, and increases egg production in female fish, a sign that chemicals in the fibers may be acting as endocrine disruptors, a new study by U.S. and Chinese scientists finds.

The minuscule fibers, which are made of polyester, polypropylene and other types of plastics, are shed or washed off of synthetic textiles used in clothing and other consumer and industrial products. Once shed, they enter wastewater and accumulate in oceans, rivers and lakes worldwide, accounting for more than 90% of microplastic pollution in some areas."Past field studies have shown that many fish eat large quantities of the fibers every day but have protective mechanisms within the gut that seem to be preventing damage," said David E. Hinton, Nicholas Distinguished Professor of Environmental Quality at Duke University. "But when you extend your study down to the tissue and cellular levels, as we did, harmful changes are observed.""In addition to the fibers that fish eat, hundreds or thousands of microfibers also pass through their gills each day, and we find that this is where much of the damage occurs," said Melissa Chernick, a researcher in Hinton's lab at Duke's Nicholas School of the Environment.The team published its peer-reviewed findings March 9 in the open-access journal Fish exposed to high levels of microfibers in their tank water for 21 days exhibited aneurysms, fused membranes and increased mucus production in their gills as well as significant changes to the epithelial cells lining their gills and other effects."There were severe changes, and a lot of them. And each change can affect respiration," Chernick said. "If you're a fish in the wild with gill damage and you're in a low-oxygen environment or being chased by a predator, you're in trouble. The same goes if you're competing with other fish for food. Just having these damages would cause you to be less competitive."Though the gut itself seems to be protected from similar damage, the new study finds that when microplastic fibers are in the gut, they may release chemical coatings that are taken up into the fish's bloodstream.The researchers are still working to identify these chemicals and determine their impacts, but one troubling effect has already been observed. Female fish exposed to fibers containing polypropylene produced more eggs over time, suggesting that chemicals that may be leaching from the microfibers are acting as endocrine disruptors.Worldwide, nearly six million tons of synthetic fibers such as polyester or polypropylene were produced in 2016. These textiles shed microfibers during washing or regular use. A single garment can shed nearly 2,000 microfibers per wash, Chernick noted, and because wastewater treatment plants aren't equipped to remove the fibers, they escape into downstream surface waters and accumulate in the environment. They can also enter the environment through sewage release, stormwater runoff or atmospheric deposition."Even if they are released miles from the ocean, they can work their way down there. So they affect both freshwater and marine organisms," Hinton said.Hinton and Chernick conducted the new study with Lingling Hu of Zhejiang University of Technology in China, and Lee Ferguson and Anne Lewis of Duke. Ferguson is an associate professor of civil and environmental engineering, ecotoxicology and environmental health. Lewis is a doctoral candidate in civil and environmental engineering.To conduct the research, they placed 27 breeding pairs of healthy Japanese medaka fish (Oryzias latipes) in water tanks with high levels of suspended microplastic fibers. They monitored fish weights, egg production, and ingestion and egestion of fibers -- how much fiber went in, how much was excreted out -- weekly. After 21 days, they examined the fish's tissues to see what changes, if any, had occurred. Tank water was changed weekly and stored for chemical analysis, to determine what dyes or additives had been released."Microplastic pollution is an environmental threat that poses increasing risks for species and ecosystems worldwide," Chernick said. "Until now, most studies have focused primarily on looking for the presence of plastics in animals, without identifying what the effects on various tissues might be. But that's exactly where our study suggests the science needs to go."

Pollution

March 16, 2020

https://www.sciencedaily.com/releases/2020/03/200316152208.htm

Sensory danger zones: How sensory pollution impacts animal survival

A new paper including research from a Utah State University scientist provides a framework for understanding how light and noise pollution affects wildlife. The framework is the product of an effort among worldwide experts in ecology and physiology and reveals the presence of "sensory danger zones," or areas where sensory pollutants influences animal activity. The study is published in the journal

"Although these results have consequences for imperiled species of conservation concern, they also suggest ways by which we may use light and sound for managing urban wildlife, mitigating wildlife-vehicle collisions, or preventing agricultural damage." said David Stoner, a research assistant professor in the Quinney College of Natural Resources at USU.In their study, the authors give an example of New York City's annual 9/11 memorial tribute. The tribute coincides with birds' annual migration from northern regions to wintering grounds in Latin America. Because birds use "celestial cues" during their migration, the 44 spotlights that form two pillars of light can attract up to 15,000 birds in a single night."(The birds) will fly in circles inside the beams until morning, often dying from exhaustion and collisions with artificially lit structures," according to Carter and co-lead authors Davide Dominoni, a researcher of biodiversity, animal health and comparative medicine at the University of Glasgow; and Wouter Halfwerk, assistant professor in the Department of Ecological Science at VU Amsterdam University.Both light pollution and traffic noise can mimic natural stimuli. For example, artificial lights cover the glow of the moon, preventing birds or insects from detecting it, or traffic noise can mask the audio spectral frequency of bird song, the researchers say.These pollutants can also redirect an animal's attention away from its task: a cougar hunting deer can be distracted by headlights or road noise."If we understand the mechanism at play, perhaps we can devise specific interventions and solutions to adopt to minimize the effect of anthropogenic impacts," Dominoni said. "For instance, light has a lot of properties. By changing some of these properties, we might very well minimize the impact light pollution has on wildlife.""Night lighting and anthropogenic sound are not localized to certain habitats and certain countries. It's a global phenomenon," he said. "Clarifying these mechanisms can help develop solutions to biodiversity loss and anthropogenic impacts worldwide."

Pollution

March 13, 2020

https://www.sciencedaily.com/releases/2020/03/200313155322.htm

First-time direct proof of chemical reactions in particulates

Researchers at the Paul Scherrer Institute PSI have developed a new method to analyse particulate matter more precisely than ever before. With its help, they disproved an established doctrine: that molecules in aerosols undergo no further chemical transformations because they are enclosed in other suspended particulate matter. In the smog chamber at PSI, they analysed chemical compounds directly in aerosols and observed how molecules dissociated and thus released, for example, gaseous formic acid into the atmosphere. These findings will help to improve the understanding of global processes involved in cloud formation and air pollution and to refine the corresponding models. The results of this investigation are published today in the journal

Anyone who takes a walk through a coniferous forest and enjoys the tangy, refreshing air is inhaling α-pinene. This is one of the volatile organic compounds in the oils of conifer trees, and it also occurs in eucalyptus and rosemary. The smell triggers pleasant feelings in most people. Less pleasant is that the compound changes in the atmosphere, under the influence of radicals, into other compounds, so-called highly oxidised organic molecules. Some of these are reactive, to some extent harmful substances. They have only recently come under scrutiny by atmospheric researchers, and their role, for example in cloud formation, is not yet understood.These highly oxidized organic molecules are less volatile than the starting substance α-pinene and therefore condense easily. Together with dust particles and other solid and liquid substances in the air, they form what we call particulate matter or aerosols."Up to now it was thought that such molecules are protected from further transformations once they have landed in particulate matter," says Andre Prévôt of the Laboratory of Atmospheric Chemistry at PSI. "It was believed that they then would not change any more, but would simply spread out over the atmosphere and eventually rain down."This widespread opinion does not correspond to reality, however, as Prévôt and his fellow researchers at PSI showed: "The reactions continue, even in the particulate matter." The molecules remain reactive and either react with each other to form larger particles or disassociate, thereby releasing for example formic acid. This common compound is found not only in ants and stinging nettles, but also in the atmosphere, where it is an important indicator of air pollution.The PSI researchers' observations should help to improve simulation models, such as those for cloud formation and air pollution. The models simulate what happens in the atmosphere to predict, for example, how a reduction in certain emissions will affect air quality.For the first time, PSI researchers analysed chemical compounds directly in particulate matter under atmospheric conditions. For this they used the PSI smog chamber, in which processes in the atmosphere can be simulated. The researchers injected a droplet of α-pinene into the chamber and caused the compound to react with ozone. Over a period of 15 hours, they observed which chemical compounds formed from α-pinene and which disappeared again afterwards.This was made possible by a new analytic device for atmospheric measurements that the researchers developed in cooperation with the company Tofwerk in Thun, Switzerland: a so-called EESI-TOF (extractive electrospray ionisation time-of-flight mass spectrometer). "It also detects larger molecules directly in the aerosol," explains atmospheric chemist Urs Baltensperger. "Previous measurement methods, on the other hand, chop up the molecules into smaller fragments at high temperatures." The new device ionises without fragmentation. "We can record each molecule separately."Tofwerk has now brought the device to market with the help of PSI, so that other atmospheric researchers can also benefit from the new method.The new analytic method can be used not only in the laboratory, but also directly on site.During the winter of 2018/19 and the summer of 2019, PSI researchers used it to investigate aerosols in the air in Zurich.As it turned out, a good third of Zurich's particulate matter in summer consists solely of reaction products of α-pinene and similar molecules. In winter, however, emissions from wood-burning systems and their reaction products come to the fore.The researchers have planned further measurement campaigns in China and India. There they want to analyse which molecules form in the air of a city with more than a million inhabitants.The research results are being published on 13 March 2020 in the journal

Pollution

March 13, 2020

https://www.sciencedaily.com/releases/2020/03/200313112127.htm

Scientists find high concentrations of toxic phenyltin compounds in local Chinese white dolphins

For years Professor Kenneth Leung Mei Yee from the HKU School of Biological Sciences and the Swire Institute of Marine Science and his research team, have been dedicated to the monitoring of toxic substances tribuyltin (TBT) and triphenyltin (TPT) compounds in our marine environment.

Globally, organotin compounds such as tribuyltin (TBT) and triphenyltin (TPT) have been widely used as antifouling agents on ship hulls and submerged mariculture facilities over the past decades. Hence, they are often detected in seawater, sediment and biota samples collected from coastal marine environments of urbanised coastal cities worldwide. At very low concentrations, these compounds can cause endocrine disruption or even death in marine organisms. The International Maritime Organisation (IMO) of the United Nations has implemented a global ban on the use of organotin compounds on the hull of sea-going vessels since 2008.Together with their collaborators, Professor Leung's research team discovered that despite a decline of TBT concentration in our marine environment in recent years, the levels of TPT contamination remained serious with an increasing trend. In addition to TPT contamination in seafood, the team's recent research has also confirmed the occurrence of biomagnification of TPT compounds along the marine food chain, resulting in very high concentrations of TPT in two top predators, the Chinese white dolphin and the finless porpoises.This is the first study in the world to confirm the trophic magnification of TPT in food webs of cetacean species, and the findings were recently published in Professor Kenneth Leung and his research team have been monitoring organotin pollution in the marine environment of Hong Kong since 2004. They discovered that TPT contamination remained serious with an increasing trend. TPT had been found in our seafood and in some case, their concentrations (e.g. those in tonguefishes) exceeded the food safety limit for human consumption. In 2017, the Government of the Hong Kong Special Administrative Region finally established a new legislation (Cap. 413, section 3) to support the IMO's global ban of using organotin compounds on vessels, and enhance the control of their release.The Chinese white dolphins prefer the inner estuary of the Pearl River Delta, while the porpoises have a greater home range from the southwest to the southeast waters of Hong Kong. Between 2015 and 2017, the study team obtained samples of stranded dolphins and porpoises from the Ocean Park Conservation Fund Hong Kong and collected samples of marine molluscs, crustaceans and fishes from waters at the northwest (i.e., inner estuary) and southwest (i.e., outer estuary) of Lantau Island, respectively. Muscle tissues of all biota samples were analysed for MPT, DPT and TPT using gas chromatography-mass spectrometry, and used for determination of trophic levels using a stable isotope ratio mass spectrometer.Alarmingly, this study also found that the highest TPT concentration in a juvenile finless porpoise (3,455.6 ng/g w. w.) was ten times higher than the highest value (310 ng/g w. w.) recorded in the same species collected from Hong Kong in 2003[2], indicating a worsening situation of TPT contamination.Based on the results of stable isotope and chemical analyses, tissue concentrations of both DPT and TPT significantly increased with increasing trophic level of marine organisms in the food web of the Chinese white dolphins (i.e., inner estuary) while only TPT tissue concentration showed a positive relationship with the trophic level of the biota in the food web of the finless porpoises. For the Chinese white dolphins, trophic magnification factors (TMF) of DPT and TPT were found to be 6.03-11.48 and 2.45-3.39, respectively. For the finless porpoises, the TMF of TPT was found to be 2.51-3.47. When a TMF is greater than 1, it indicates that the chemical compound can be biomagnified through the marine food chain.The results of the study suggest that high trophic organisms including humans are likely to be vulnerable to the exposure of DPT and TPT compounds via dietary intake due to the high trophic magnification potential of these chemicals. Therefore, environmental and human health risks of these compounds should be assessed with consideration of their biomagnification potentials along the food chain.Regarding ways to reduce the health risk of TPT exposure, Professor Leung said, "The public should avoid and minimise the consumption of very large fishes such as sharks and Reeve's croakers, and also benthic fish species such as the flathead and tongue sole fishes, as they probably contain high concentrations of TPT and other persistent organic pollutants in their tissues. Instead, they can consume crustaceans (e.g. shrimps and crabs), shellfishes (e.g. mussels, clams and oysters), and small fishes as an effective way to reduce the intake of TPT and other chemical contaminants."Dr James Lam Chung Wah, an environmental toxicologist and Assistant Professor at the Department of Science and Environmental Studies of the Education University of Hong Kong, who was not involved in the study, commented, "This interesting and impactful study led by HKU provided solid evidence of such a significant biomagnification of TPT along the marine food chain of marine mammals. Their results also highlight the greater impact of TPT on top predators in the sea and in humans through seafood consumption." He also added, "To improve the current situation of organotin contamination, we must reduce their use and release at the source. Around the world, every government needs to play a part in strengthening the regulation and control of the use of toxic chemicals (like TPT compounds) in order to minimise their release into the environment."[1] Harino et al. 2007. Accumulation of organotin compounds in tissues and organs of stranded whales along the coasts of Thailand. Arch. Environ. Contam. Toxicol. 53: 119-125. [2] Nakayama et al. 2009. Temporal and spatial trends of organotin contamination in the livers of finless porpoises (

Pollution

March 10, 2020

https://www.sciencedaily.com/releases/2020/03/200310164748.htm

Some domesticated plants ignore beneficial soil microbes

While domestication of plants has yielded bigger crops, the process has often had a negative effect on plant microbiomes, making domesticated plants more dependent on fertilizer and other soil amendments than their wild relatives.

In an effort to make crops more productive and sustainable, researchers recommend reintroduction of genes from the wild relatives of commercial crops that restore domesticated plants' ability to interact with beneficial soil microbes.Thousands of years ago, people harvested small wild plants for food. Eventually, they selectively cultivated the largest ones until the plump cereals, legumes, and fruit we know today evolved. But through millennia of human tending, many cultivated plants lost some ability to interact with soil microbes that provide necessary nutrients. This has made some domesticated plants more dependent on fertilizer, one of the world's largest sources of nitrogen and phosphorus pollution and a product that consumes fossil fuels to produce."I was surprised how completely hidden these changes can be," said Joel Sachs, a professor of biology at UC Riverside and senior author of a paper published today in Bacteria and fungi form intimate associations with plant roots that can dramatically improve plant growth. These microbes help break down soil elements like phosphorus and nitrogen that the plants absorb through their roots. The microbes also get resources from the plants in a mutually beneficial, or symbiotic, relationship. When fertilizer or other soil amendments make nutrients freely available, plants have less need to interact with microbes.Sachs and first author Stephanie Porter of Washington State University, Vancouver, reviewed 120 studies of microbial symbiosis in plants and concluded that many types of domesticated plants show a degraded capacity to form symbiotic communities with soil microbes."The message of our paper is that domestication has hidden costs," Sachs said. "When plants are selected for a small handful of traits like making a bigger seed or faster growth, you can lose a lot of important traits relating to microbes along the way."This evolutionary loss has turned into a loss for the environment as well.Excess nitrogen and phosphorus from fertilizer can leach from fields into waterways, leading to algae overgrowth, low oxygen levels, and dead zones. Nitrogen oxide from fertilizer enters the atmosphere, contributing to air pollution. Fossil fuels are also consumed to manufacture fertilizers.Some companies have begun selling nitrogen-fixing bacteria as soil amendments to make agriculture more sustainable, but Sachs said these amendments don't work well because some domesticated plants can no longer pick up those beneficial microbes from the soil."If we're going to fix these problems, we need to figure out which traits have been lost and which useful traits have been maintained in the wild relative," Sachs said. "Then breed the wild and domesticated together to recover those traits."

Pollution

March 9, 2020

https://www.sciencedaily.com/releases/2020/03/200309221340.htm

Wearing clothes could release more microfibers to the environment than washing them

Wearing clothes can release even greater quantities of microfibres to the environment than washing them, new research shows.

In a first-of-its-kind study, scientists from the Institute for Polymers, Composites and Biomaterials of the National Research Council of Italy (IPCB-CNR) and the University of Plymouth compared four different items of polyester clothing and how many fibres were released when they were being worn and washed.The results showed that up to 4,000 fibres per gram of fabric could be released during a conventional wash, while up to 400 fibres per gram of fabric could be shed by items of clothing during just 20 minutes of normal activity.Scaled up, the results indicate that one person could release almost 300million polyester microfibres per year to the environment by washing their clothes, and more than 900million to the air by simply wearing the garments.In addition, there were significant differences depending on how the garments were made, which the researchers concluding that clothing design and manufacturer has a major role to play in preventing microfibres from being emitted to the environment.The research, published in the journal Dr Francesca De Falco, Research Fellow at IPCB-CNR and lead author on the current research, said: "Recently, more evidence has been accumulating on the presence of synthetic microfibres not only in aquatic environments, but also in atmospheric ones. That is why we decided to design this set of experiments to study microfibre release by garments to both media. This is a type of pollution that should be mainly fought at its source, the fabric itself, but we investigated the influence of different textile parameters on the release. Results have shown that textiles with a very compact structure like woven, with yarns highly twisted and composed of continuous filaments, can release less microfibres to both air and water."The study compared four different garments, which were washed at 40°C with any released fibres being collected. It showed that anywhere between 700 and 4,000 individual fibres could be released per gram of fabric during a single wash.The researchers also created a dedicated clean lab used by multiple volunteers wearing each of the four garments separately and then performing a sequence of movements simulating a mix of real life activities. Any fibres emitted by the garments were then collected, with up to 400 being released per gram of fabric in just 20 minutes.The polyester/cotton garment showed the greatest release during both washing and wearing, with a woven polyester one releasing the least quantity of microfibres.However, based on the overall results, the researchers say previous estimations of microplastic pollution have actually underestimated the importance of synthetic textiles since they did not take into account the quantities released directly into the air.Professor Richard Thompson OBE, Head of the University of Plymouth's International Marine Litter Research Unit, was a senior author on the current study and gave evidence to both the UK Government's Sustainability of the Fashion Industry inquiry and the recent OECD Forum on due diligence in the garment and footwear sector.He added: "The key story here is that the emission of fibres while wearing clothes is likely of a similar order of magnitude as that from washing them. That constitutes a substantial and previously unquantified direct release to the environment. The results also show textile design can strongly influence both release to the air and release due to laundering; that is a crucial message highlighting the importance of sustainable design for the fashion industry. Indeed many of the current issues associated with the environmental impacts of plastic items stem from a lack of holistic thinking at the design stage."

Pollution

March 9, 2020

https://www.sciencedaily.com/releases/2020/03/200309130105.htm

Ship noise leaves crabs too stressed to hide from danger

The ocean is getting too loud even for crabs. Normally, shore crabs (

"Prior work had shown that ship noise can be stressful for shore crabs, so in this study, we wanted to address how that stress might affect behaviors they rely on for survival," says first author Emily Carter, a graduate from the University of Exeter. Unlike frogs or bats, who use sound to communicate or hunt, crabs don't primarily use sound to interact with each other. However, this study demonstrates that noise pollution can still affect important shore crab survival behaviors like the ability to camouflage and quickly respond to danger.Carter placed dark-shelled juvenile shore crabs into white tanks. Within the tanks, crabs were exposed to the underwater sounds of a cruise ship, container ship, and oil tanker. As a control, other crabs listened to natural water sounds -- played either quietly, or loud at a similar amplitude to the ship noise. Over 8 weeks, the crabs exposed to ship noise lightened their color to match their tanks only half as much as those which heard ambient water alone (both quiet and loud). Carter believes this reduced change in color demonstrates the unique effect of ship noise pollution on crab camouflage."Color change in shore crabs is a slow, energetically costly process that's controlled by hormones that activate specialized pigment cells across their shell," says Carter. "Stress consumes energy and disrupts hormone balance, so we believe that the stress caused by ship noise either drains the crabs of the energy required to change color properly or disrupts the balance of hormones necessary to make that change." The crabs also grew and molted much more slowly, showing that ship noise impacts multiple aspects of shore crab physiology.What's more is that when crabs were subjected to a simulated shore bird attack, those that heard ship noise didn't run and hide as they would normally. "About half of the crabs exposed to ship noise did not respond to the attack at all, and the ones that did were slow to hide themselves," says Carter. "Similar to how people have trouble concentrating when stressed, the nature of their response indicates that they couldn't process what was happening, as if that awareness and decision-making ability just wasn't there."In noise pollution research, the sounds of ships and other forms of human-made noise are typically studied for their effects on animals who directly use sound. Here, Carter, co-author Tom Tregenza, professor of evolutionary ecology at the University of Exeter, and senior author Martin Stevens, professor of sensory and evolutionary ecology at the University of Exeter, show that the noise pollution field should also consider behaviors based on their importance to survival rather than whether they have a direct link with noise."This work shows how processes like color change, which are not directly linked to acoustics, can still be affected by noise and how even animals like crabs are impacted by noise pollution -- not just species that actively use sound, such as many fish or mammals," says Stevens.To expand upon this research, Stevens' lab is investigating how multiple stressors, including that of noise pollution and warming oceans, could work synergistically to disrupt the coloration and behavior of marine organisms.

Pollution

March 5, 2020

https://www.sciencedaily.com/releases/2020/03/200305135048.htm

Air pollution is one of the world's most dangerous health risks

Polluted air is a public health hazard that cannot be evaded. It is widely known that long-term exposure to air pollution enhances the risks of cardiovascular and respiratory diseases. Scientists from the Max Planck Institute for Chemistry and the University Medical Center Mainz now calculated in a new study that the global, public loss of life expectancy caused by air pollution is higher than many other risk factors such as smoking, infectious diseases or violence.

Air pollution caused 8.8 million premature deaths worldwide in 2015. This corresponds to an average reduction in life expectancy per capita of 2.9 years. In comparison, tobacco smoking reduces the life expectancy by an average of 2.2 years (7.2 million deaths), HIV / AIDS by 0.7 years (1 million deaths), parasitic and vector-borne diseases such as malaria -- by 0.6 years (600,000 deaths). "Air pollution exceeds malaria as a cause of premature death by a factor of 19; it exceeds violence by a factor of 17 and HIV / AIDS by a factor of 9. Given the huge impact on public health and the global population, one could say that our results indicate an air pollution pandemic," said Jos Lelieveld, director at Max Planck Institute for Chemistry and first author of the study.This study is the first to examine the global impact of air pollution on human health compared to other risk factors worldwide. "Our comparison of different global risk factors shows that ambient air pollution is a leading cause of premature mortality and loss of life expectancy, in particular through cardiovascular diseases," says Thomas Münzel, director of the Cardiology Center at the University Medical Center in Mainz and co-author of the paper.The scientists examined the connection between exposure to pollutants and the occurrence of diseases. In order to calculate the worldwide exposure to pollutants, which primarily include fine particles and ozone, the researchers used an atmospheric chemical mode. They then combined the exposure data with the Global Exposure -- Mortality Model that derives from many epidemiological cohort studies. Using these tools and data, scientists investigated the effects of different pollution sources, distinguishing between natural (wildfires, aeolian dust) and anthropogenic emissions, including fossil fuel use. Based on their results they could estimate the disease-specific excess mortality and loss of life expectancy in all countries world-wide.The study results show that the mortality caused by ambient air pollution is highest in East Asia (35 percent) and South Asia (32 percent), followed by Africa (11 percent), Europe (9 percent) and North- and South America (6 percent). Lowest mortality rates are found in Australia (1,5 percent) associated with the strictest air quality standards of all countries. "We understand more and more that fine particles primarily favor vascular damage and thus diseases such as heart attack, stroke, cardiac arrhythmia and heart failure. It is of outmost importance that air pollution is adopted as a cardiovascular risk factor and that it is distinctly mentioned in the ESC/AHA guidelines of prevention, acute and coronary syndromes and heart failure," continued Münzel.According to the findings of the study, almost two thirds of the deaths caused by air pollution, namely around 5.5 million a year are avoidable, and the majority of polluted air comes from the use of fossil fuels. The researchers estimate that the average life expectancy world-wide would increase by more than a year if the emissions from the use of fossil fuels were eliminated.The team from the University Medical Center Mainz and Max Planck Institute for Chemistry published a similar paper last year focusing on the consequences of air pollution in Europe. According to the earlier study, nearly 800,000 Europeans die prematurely every year due to illnesses caused by air pollution. Polluted air shortens the lifespan of Europeans by more than two years.

Pollution

March 5, 2020

https://www.sciencedaily.com/releases/2020/03/200305132125.htm

Unexpected discovery: Blue-green algae produce oil

Cyanobacteria -- colloquially also called blue-green algae -- can produce oil from water and carbon dioxide with the help of light. This is shown by a recent study by the University of Bonn. The result is unexpected: Until now, it was believed that this ability was reserved for plants. It is possible that blue-green algae will now also become interesting as suppliers of feed or fuel, especially since they do not require arable land. The results have now been published in the journal

What do rapeseed, avocado and olive tree have in common? They are all used by humans as producers of oil or fat. However, the ability to produce oil from water and carbon dioxide with the help of light is something that is essentially common to all plants, from unicellular algae to the giant sequoia trees. "We have now shown for the first time that cyanobacteria can do the same," explains biologist Prof. Dr. Peter Dörmann from the Institute of Molecular Physiology and Biotechnology of Plants (IMBIO) at the University of Bonn. "This was a complete surprise, not only to us."Until now, experts had assumed that cyanobacteria lack this property. After all, they are actually bacteria, even if their trivial name "blue-green algae" suggests otherwise. They therefore differ considerably from plants in many respects: Cyanobacteria are closer related to the intestinal bacterium E. coli than to an olive tree. "There are indeed ancient reports in the literature that cyanobacteria can contain oil," says Dörmann. "But these have never been verified."The scientist has been working at IMBIO for many years on an enzyme that catalyzes one of the steps in oil synthesis in plants. The enzyme is active in the chloroplasts, the green-colored cell components that are responsible for photosynthesis. It is thanks to these that plants can produce energy-rich chemical compounds with the help of sunlight.Many scientists suspect that chloroplasts originally come from cyanobacteria. This is because they, unlike all other groups of bacteria, also master the photosynthesis typical of plants, with the release of oxygen. According to this theory, more than a billion years ago, a primordial plant cell "swallowed" a cyanobacterium. The bacterium then lived on in the cell and supplied it with photosynthesis products. "If this endosymbiont hypothesis is correct, then the oil synthesis enzyme of the chloroplasts might originally come from cyanobacteria," explains Dörmann.He pursued this possibility together with his doctoral student Mohammed Aizouq. The scientists searched the genomes of various cyanobacteria for a gene that is similar to the genetic make-up of the enzyme involved in plant oil synthesis. With success: They found a gene for a so-called acyltransferase in the blue-green algae; the plant enzyme also belongs to this group. Further tests showed that cyanobacteria do actually produce oil with this enzyme, even if only in small quantities.The result is on the one hand interesting from an evolutionary-biological point of view: It shows that a certain part of the oil synthesis machinery in the chloroplasts of the plants probably originates from cyanobacteria. However, plants today mainly use other metabolic pathways to produce oil. Furthermore, the result may open up new possibilities for producing animal feed or biofuels. This is because, unlike oil plants such as rapeseed, cyanobacteria do not need arable land to grow -- a container with culture medium and sufficient light and heat is enough for them.This may make them suitable for deserts, for example, where they can be used to produce oils for car engines without competing with food crops. Especially since combustion would only release the carbon dioxide that the cyanobacteria had previously extracted from the air during oil production. The microorganisms would thus make a contribution to climate protection. In any case, the cyanobacteria living in the world's oceans bind considerable quantities of the greenhouse gas. It is estimated that without their contribution, the concentration of carbon dioxide in the atmosphere would be twice as high."Similar experiments are already underway with green algae," explains Dörmann. "However, these are more difficult to maintain; moreover, they cannot be easily biotechnologically optimized to achieve the highest possible oil production rate." This could be different with cyanobacteria. The species studied at the University of Bonn produces only very small amounts of oil. "It is nevertheless quite possible that other species are considerably more productive," says the biologist. Furthermore, blue-green algae can be genetically modified relatively easily, similar to other bacteria. "It is therefore certainly possible that the oil yield could be significantly increased again with biotechnological means."

Pollution

March 2, 2020

https://www.sciencedaily.com/releases/2020/03/200302200734.htm

The world faces an air pollution 'pandemic'

Air pollution is responsible for shortening people's lives worldwide on a scale far greater than wars and other forms of violence, parasitic and vector-born diseases such as malaria, HIV/AIDS and smoking, according to a study published in

Professors Jos Lelieveld and Thomas Münzel, of the Max Planck Institute for Chemistry and the Department of Cardiology of the University Medical Centre Mainz in Mainz, Germany, who led the research, say the findings suggest the world is facing an air pollution "pandemic."Using a new method of modelling the effects of various sources of air pollution on death rates, the researchers estimated that globally air pollution caused an extra 8.8 million premature deaths a year in 2015. This represents an average shortening of life expectancy of nearly three years for all persons worldwide.In comparison, tobacco smoking shortens life expectancy by an average of 2.2 years (7.2 million deaths), HIV/AIDS by 0.7 years (1 million deaths), diseases like malaria that are carried by parasites or insects such as mosquitoes, ticks and fleas by 0.6 years (600,000 deaths), and all forms of violence (including deaths in wars) by 0.3 years (530,000 deaths). The researchers looked at the effect of air pollution on six categories of disease: lower respiratory tract infection, chronic obstructive pulmonary disease, lung cancer, heart disease, cerebrovascular disease leading to stroke, and other, non-communicable diseases, which include conditions such as high blood pressure and diabetes. They found that cardiovascular diseases (heart disease and cerebrovascular disease combined) are responsible for the greatest proportion of shortened lives from air pollution: 43% of the loss in life expectancy worldwide.They also found that air pollution had a greater effect on shortening lives in older people, with the exception of deaths in children aged under five in low income countries, such as Africa and South Asia. Globally, about 75% of deaths attributed to air pollution occur in people aged over 60 years.This is the first study to show the effects of air pollution on deaths according to age, type of disease and also its effect on life expectancy at the level of individual countries and regions.Professor Jos Lelieveld, who is also from the Cyprus Institute Nicosia, Cyprus, said: "It is remarkable that both the number of deaths and the loss in life expectancy from air pollution rival the effect of tobacco smoking and are much higher than other causes of death. Air pollution exceeds malaria as a global cause of premature death by a factor of 19; it exceeds violence by a factor of 16, HIV/AIDS by a factor of 9, alcohol by a factor of 45, and drug abuse by a factor of 60."Prof Münzel said: "Since the impact of air pollution on public health overall is much larger than expected, and is a worldwide phenomenon, we believe our results show there is an 'air pollution pandemic'. Policy-makers and the medical community should be paying much more attention to this. Both air pollution and smoking are preventable, but over the past decades much less attention has been paid to air pollution than to smoking, especially among cardiologists."In this paper we distinguished between avoidable, human-made air pollution and pollution from natural sources such as desert dust and wildfire emissions, which cannot be avoided. We show that about two-thirds of premature deaths are attributable to human-made air pollution, mainly from fossil fuel use; this goes up to 80% in high-income countries. Five and a half million deaths worldwide a year are potentially avoidable."It is important that policy-makers and the medical community realise that air pollution is an important risk factor for heart and blood vessel disease. It should be included as risk factor, along with smoking, diabetes and high blood pressure and cholesterol, in the guidelines of the European Society of Cardiology and the American Heart Association on the prevention of acute and chronic heart syndromes and heart failure."The researchers estimate that if air pollution was reduced by removing fossil fuel emissions, the average life expectancy worldwide would increase by just over a year, and by nearly two years if all human-made emissions were removed.However, there are large differences between regions due to the diversity in emissions. In East Asia, which has the highest loss of life expectancy due to avoidable air pollution, three of the average of four years of lost life expectancy could be prevented by the removal of human-made emissions; whereas in Africa, where population growth is rapid and pollution from dust predominates, only 0.7 of 3.1 years lost could be prevented. In Europe, there is an average of 2.2 years of lost life expectancy, 1.7 of which could be prevented, and in North America there is an average of 1.4 years of lost life expectancy, of which 1.1 could be prevented, mostly by phasing out fossil fuels.Prof Lelieveld said: "In Africa, air pollution represents a health risk that is comparable to HIV/AIDS and malaria. However, in most of the rest of the world air pollution is a much greater health risk. When we looked at how pollution played a role in several diseases, its effect on cardiovascular disease was by far the largest -- very similar to the effect of smoking. Air pollution causes damage to the blood vessels through increased oxidative stress, which then leads to increases in blood pressure, diabetes, stroke, heart attacks and heart failure."The researchers used exposure data from a model that simulates atmospheric chemical processes and the way they interact with land, sea and chemicals emitted from natural and human-made sources such as energy generation, industry, traffic and agriculture. They applied these to a new model of global exposure and death rates and to data from the Global Burden of Disease, which included information on population density, geographical locations, ages, risk factors for several diseases and causes of death. They estimated the death rates and loss of life expectancy from different causes of air pollution compared to other causes of premature death for countries and regions around the world.Limitations of the study include the fact there is uncertainty surrounding the estimates, so the size of the effect of air pollution on deaths could be larger or smaller. Nevertheless, such uncertainty also applies to other health risk factors, including smoking. More research is needed to understand fully the mechanisms involved in the associations seen between air pollution and a variety of diseases.

Pollution

March 2, 2020

https://www.sciencedaily.com/releases/2020/03/200302153608.htm

Is there a technological solution to aquatic dead zones?

Could pumping oxygen-rich surface water into the depths of lakes, estuaries, and coastal ocean waters help ameliorate dangerous dead zones? New work led by Carnegie's David Koweek and Ken Caldeira and published open access by

When excessive nutrients from agriculture and other human activities wash into waterways, it can create a dangerous phenomenon called eutrophication. This can lead to low-oxygen dead zones called hypoxia."Low-oxygen dead zones are one of the most-pervasive problems plaguing both marine and freshwater systems around the world and a major problem for communities that depend on fishing," Koweek said.Efforts to fight hypoxia often focus on reducing agricultural runoff and on preventing nutrients from being overloaded into waterways. But this is a very slow process that involves changing farming practices, upgrading wastewater treatment facilities, and altering home fertilizer usage.Koweek and Caldeira led a team that investigated a proposed technological remedy, called downwelling, which could complement nutrient-reduction programs. This involves pumping naturally more-oxygenated water from the surface down into the depths of the affected body of water."In theory, downwelling would create vertical mixing in the water, distributing oxygen and preventing hypoxic conditions from taking hold," Koweek explained. "We wanted to test this idea and see if it would really work."The team built models to compare downwelling to the two most-commonly used technological techniques for preventing dead zones -- bubbling oxygen from the bottom and spraying fountain water across the surface. Their models indicate that downwelling would be three to 100 times more efficient than bubbling and 10,000 to a million times more efficient than fountains.They then did a field experiment at the Searsville Reservoir in Woodside, California, which demonstrated that downwelling could increase oxygen saturation in the immediate area surrounding the pumps by between 10 and 30 percent, enough to alleviate hypoxic stress for many marine organisms. However, this did not extend for more than a handful of meters beyond the vicinity of the pipes through which the surface water was pumped. This means that an extensive network would be necessary for any major effort to fight dead zones in an economically important or ecologically sensitive area.According to the researchers, their work indicates that downwelling technology may show potential to scale up to larger areas in which annual dead zones create great ecological and economic distress, such as the Chesapeake Bay or the Gulf of Mexico. They estimate that the energy required to power the pumps could cost tens of millions of dollars each year. Operating downwelling pumps year-round in the Chesapeake could cost between $4 and $47 million; In the Gulf, the same could cost between $26 and $263 million.But these price tags are relatively small compared to the costs of upgrades to wastewater treatment facilities and fertilizer-reduction programs that limit nutrient inputs to the water bodies. This suggests that downwelling technology could be used alongside longer-term plans to reduce nutrient pollution."Reducing nutrient pollution is the only way to eliminate hypoxia permanently," Calderia said. "However, our work shows that downwelling is a technological solution that could mitigate the risk of low-oxygen dead zones while nutrient management strategies are put in place."

Pollution

February 28, 2020

https://www.sciencedaily.com/releases/2020/02/200228125234.htm

Containing methane and its contribution to global warming

Methane is a gas that deserves more attention in the climate debate as it contributes to almost half of human-made global warming in the short-term. A new IIASA study shows that it is possible to significantly contribute to reduced global warming through the implementation of available technology that limits methane release to the atmosphere.

According to the study published in the journal "To develop policy strategies to mitigate climate change through reductions of global non-COUsing the IIASA Greenhouse Gases -- Air Pollution Interactions and Synergies (GAINS) model, the researchers endeavored to find out how well the GAINS bottom-up inventory of methane emissions at country and source-sector level between 1990-2015 match top-down estimates of the global concentration of methane measured in the atmosphere. In addition, they wanted to see how much methane would be emitted globally until 2050 if we take no further measures to reduce emissions.The results show that at the global level, the GAINS methane inventory matches the top-down estimate of human-made methane emissions' contribution to the atmospheric concentration of methane quite well. A reasonable match between bottom-up and top-down budgets, both at the global and regional levels, is important for the confidence in bottom-up inventories, which are a prerequisite for policy strategies to be perceived as "certain enough" by stakeholders in climate mitigation.The authors' analysis revealed a strong increase in emissions after 2010, which confirms top-down measurements of increases in the atmospheric methane concentration in recent years. According to this study, these are explained by increased methane emissions from shale gas production in North America, increased coal mining in countries outside of China, for instance, Indonesia and Australia, and increased generation of waste and wastewater from growing populations and economic development in Asia and Africa. In addition, the findings showed a small but steady increase in emissions from beef and dairy production in Latin America and Africa, highlighting how different the distribution of emission source sectors are across different world regions.The findings further show that without measures to control methane emissions, there would be a global emission increase of about 30% until 2050. While it would technically be possible to remove about 38% of these emissions by implementing available abatement technology, it would still mean that a significant amount of methane would be released between 2020 and 2050, making it impossible for the world to stay below 1.5°C warming.With that said, the researchers point out that technical abatement potentials can still be used to achieve considerable reductions in methane emissions in the near-term and at a comparably low cost. Between 30% and 50% of future global methane emissions can be removed at a cost below 50 €/t CO2eq. The use of fossil fuels will however also have to be phased-down to really make a difference. Technical abatement potentials are particularly limited in agriculture, which suggests that these emissions must be addressed through non-technical measures, such as behavioral changes to reduce milk and meat consumption, or institutional and socioeconomic reforms to address smallholder livestock herding as a means of risk management in Africa and South-East Asia."There is no one-size fits all solution for the whole world. In the Middle East and Africa, for instance, oil production is a major contributor to methane emissions with relatively extensive potentials for emission reductions at low cost. In Europe and Latin America, dairy and beef production are the main sources with relatively limited technical mitigation potentials, while in North America it is emissions from shale gas extraction that can significantly contain emissions at a low cost. Our study illustrates just how important it is to have a regional- and sector-specific approach to mitigation strategies," concludes Hoglund-Isaksson.

Pollution

February 26, 2020

https://www.sciencedaily.com/releases/2020/02/200226131329.htm

Motley crew: Rust and light a possible answer to the conundrum of hydrogen fuel production

Production of hydrogen fuel is a key goal towards the development of sustainable energy practices, but this process does not have feasible techniques yet. A team of Japanese scientists from Tokyo University of Science, led by Prof Ken-ichi Katsumata, have identified a novel technique of using rust and light to speed up hydrogen production from organic waste solution, a finding that can revolutionize the clean energy industry.

In today's narrative of climate change, pollution, and diminishing resources, one fuel could be a game-changer within the energy industry: hydrogen. When burned in a combustion engine or in an electrical power-plant, hydrogen fuel produces only water-making it far cleaner than our current fossil fuels. With no toxic gas production, no contribution to climate change, and no smog, hydrogen may be the answer to a future of cleaner energy, so why is it not more widely used?There are two reasons for this. First, hydrogen is highly flammable and leaks very easily from storage tanks, causing potential explosion hazards during storage and transport. Second, although pure hydrogen occurs naturally on Earth, it is not found in quantities sufficient for cost-effective utilization. Hydrogen atoms must be extracted from molecules like methane or water, which requires a large amount of energy. Although several techniques exist to produce hydrogen fuel, scientists are yet to make this process "efficient" enough to make hydrogen a commercially competitive fuel on the energy market. Until this is achieved, fossil fuels will probably continue to dominate the industry.For decades, scientists have been working towards a cheap, efficient, and safe way to produce hydrogen fuel. One of the most promising methods to achieve this is through solar-driven processes, using light to speed up (or "catalyze") the reaction to split water molecules into oxygen and hydrogen gas. In the 1970s, two scientists described the Honda-Fujishima effect, which uses titanium dioxide as a photocatalyst in hydrogen production. Building on this research, a team of Japanese researchers led by Prof Ken-ichi Katsumata of Tokyo University of Science, sought to use a cheaper, more readily available semiconductor catalyst for this reaction, with the hope to increase its efficiency even further, reducing the production costs and safety of hydrogen fuel. Their study published in The experiment conducted by Prof Katsumata and colleagues aimed to address common challenges encountered in using semiconductor catalysts in solar-driven hydrogen production. There are three major obstacles described by the authors. The first is the need for the catalyst material to be suitable for the use of light energy. The second is that most photocatalysts currently used require rare or "noble" metals as cocatalysts, which are expensive and difficult to obtain. The last problem arises from the actual production of hydrogen and oxygen gases. If not separated straight away, the mixture of these two gases can at best reduce the hydrogen fuel output, and at worst, cause an explosion. Therefore, they aimed to find a solution that can not only increase the reaction's efficiency, but also successfully prevent hydrogen and oxygen from re-coupling and creating a potential hazard.The team identified a promising candidate catalyst in α-FeOOH (or rust) and set out an experiment to evaluate its efficiency for hydrogen production and the optimal experimental conditions for its activation. "We were really surprised at the generation of hydrogen using this catalyst," states Prof Katsumata, "because most of the iron oxides are not known to reduce to hydrogen. Subsequently, we searched for the condition for activating α-FeOOH and found that oxygen was an indispensable factor, which was the second surprise because many studies showed that oxygen suppresses hydrogen production by capturing the excited electrons." The team confirmed the production mechanism of hydrogen from water-methanol solution using a 'gas-chromatography-mass-spectrometry' method, showing that α-FeOOH was 25 times more active than the titanium dioxide catalyst used in previous research, supporting stable hydrogen production for more than 400 hours!More research will be required to optimize this process. Prof Katsumata elaborates: "The specific function of the oxygen in activating light-induced α-FeOOH has not been unveiled yet. Therefore, exploring the mechanism is the next challenge." For now, these findings of Katsumata and his colleagues represent new advancements in the production of a clean, zero-emissions energy source that will be central to the sustainable societies of the future!

Pollution

February 26, 2020

https://www.sciencedaily.com/releases/2020/02/200226130510.htm

Tadpoles break the tension with bubble-sucking

When it comes to the smallest of creatures, the hydrogen bonds that hold water molecules together to form "surface tension" lend enough strength to support their mass: think of insects that skip across the surface of water. But what happens to small creatures that dwell below the surface of the water?

UConn researchers have taken a close look, and in research published recently in The Tadpoles often live in water with low oxygen levels where fewer predators lurk, but this also means the tadpoles need a way to get to air to breathe. Tadpoles have gills, but they don't usually provide enough oxygen for them to survive, so most tadpoles also have lungs and breathe air as a back-up. But during the earliest period of their lives, tadpoles are too small to break through the water's surface to breathe. Luckily for the tadpoles, they have a way to work around this problem, says ecology and evolutionary biology professor Kurt Schwenk.Tadpoles will often charge upward toward the surface of the water, yet due to their small size and the surface tension of the water, they bounce back down. While watching this during an unrelated study on aquatic salamanders feeding on tadpoles, Schwenk noticed a bubble left behind after one tadpole's visit to the underside of the water's surface."Many researchers have observed tadpoles breathing at the surface before, but unless you look very closely and slow the action down, you can't see what is actually happening," says Schwenk.Using high-speed macro-videography, Schwenk and graduate researcher Jackson Phillips captured hundreds of breathing events on film shooting at the super slow motion rate of 500-1000 frames per second. The tadpoles were seen to use a never-before-described breathing mechanism they call "bubble-sucking," a novel breathing mechanism for vertebrates captured with novel technology."This research would have been much more difficult to do before high-speed video cameras were developed, and that is probably why the behavior has not been described before," says Schwenk.The researchers studied tadpoles from five species of frogs -- four of which can be found in Connecticut. What they found was that tadpoles of all species were able to inflate their lungs within a few days of hatching, despite being too small to access air.Instead of breaching the water's surface, the tadpoles were seen to bubble-suck. To bubble-suck, the tadpoles first attach their mouths to the undersurface of the water. They then open their jaws wide and draw a bubble of air into the mouth. What happens next was visible through the skin of some of the tadpoles. The tadpoles empty their lungs into their mouths, where the air mixes with the fresh air of the newly sucked bubble. After the mouth closes, the air bubble is forced down into the lungs, but since the bubble is larger than their lung capacity, a portion of the air remains in the mouth, which is then expelled as a small bubble that floats to the surface. The entire process takes about three tenths of a second.Bubble-sucking appears to be an adaptation the tadpoles use while they are still small. When they grow large enough and charge the water's surface, they are able to break the surface tension and "breach-breathe." The researchers observed bubble-sucking in other species, as well -- larval salamanders and even snails. They note that it is likely limited to organisms that can create the suction necessary, therefore arthropods, like insects, cannot bubble-suck."As a result of an accidental observation, my research has taken a turn -- I never expected to work on these organisms," Schwenk says. "Before, I thought that tadpoles were uninteresting. But now I find them deeply fascinating."Schwenk says this accidental discovery conveys an important point about research in general."These frog species are incredibly well-studied and very common," he says. "Yet, one can learn new things even about the most common animals, which is a good lesson for students, because when getting into research, one can be left with the sense that it has all been done. The fact is, it hasn't been -- we just have to be observant and keep asking questions."

Pollution

February 24, 2020

https://www.sciencedaily.com/releases/2020/02/200224183505.htm

Reducing nutrient pollution helps coral resist bleaching

Coral reefs are not doomed. Although human activities threaten the iconic ecosystems in many different ways, scientists maintain that reefs can continue to thrive with the right assistance.

A study by researchers at UC Santa Barbara details how reducing nutrient pollution can help prevent coral from bleaching during moderate heatwaves. The results, which appear in the journal Reef-building corals host beneficial algae within their tissues. In exchange for protection and nitrogen, the algae provide the coral with sugars. All is well until the water gets too warm.At higher temperatures, the algae's photosynthesis goes into overdrive, and the chemical balance between the coral and the algae breaks down. At a certain point, the coral ejects its tenant in a process known as bleaching. Coral can survive for a time without their algae, so recovery is possible if conditions return to normal quickly. But in the absence of its partner the coral will eventually die, and the worse the bleaching is, the more likely that is to happen.Experiments in the lab, as well as a few small field studies, began to suggest to researchers that nitrogen pollution, such as from fertilizer and sewage runoff, could exacerbate bleaching. Excess nitrogen in the water can short-circuit the beneficial partnership between corals and the algae. However, until now, it was not known if nutrient effects on bleaching occurred in many corals over large areas.The UC Santa Barbara scientists decided to investigate the effects of nitrogen on coral bleaching -- on the scale of an entire island -- as part of their long-term ecological research project on the island of Moorea in French Polynesia.The team surveyed more than 10,000 corals around Moorea during a moderate heatwave in 2016. They studied individual coral colonies in different habitats to capture the variability at a high resolution across the island as a whole. Since nitrogen concentrations naturally fluctuate in seawater, the researchers took samples from Turbinaria ornata, a large alga common on the reefs around Moorea. This provided a record of the nitrogen available to corals in the months leading up to the heatwave."These relationships are very complex," said lead author Mary Donovan, a postdoctoral researcher at the university's Marine Science Institute. "So, studying them at spatial and temporal scales that match those happening in nature is critical to revealing these really important interactions."The team found that high levels of nitrogen pollution lowered the temperature at which coral began to bleach. It also increased the severity of bleaching. "It basically doubles how severe the bleaching is," said Russ Schmitt, a professor in the Department of Ecology, Evolution, and Marine Biology (EEMB). Coral bleached at extreme temperatures regardless of how much nitrogen was in the system, but even a little excess nitrogen could tip the scale toward severe bleaching under moderate heat conditions.The scientists looked at the two most common types of branching coral in Moorea. They expected them to respond differently to nutrient pollution, since one is more sensitive to temperature stress than the other. However, both types of corals showed identical responses. This suggested that the strong effect nitrogen pollution has on coral at temperatures normally below levels that trigger bleaching may apply broadly to many coral species.Climate change has increased the strength and frequency of marine heatwaves, which has increased the severity of bleaching, according to the researchers. Coral reefs are at a tipping point, they explained, so every strategy available to encourage reef health and resilience needs to be explored. "This study shows that it is possible to take some local actions such as reducing nutrient pollution to give reefs a chance, at least in the near term," said coauthor Sally Holbrook, also a professor in EEMB.The researchers plan to continue investigating how the effect of nutrient pollution on bleaching translates into coral mortality. The team conducted a similar survey in 2019, a year that saw some of the highest water temperatures on record around the island of Moorea. Their findings should offer a better account of longer-term effects nutrient pollution has on coral reef ecosystems."Marine heatwaves and coral bleaching are the defining challenge facing coral reefs in the 21st century," said coauthor Deron Burkepile, a professor in EEMB. "Managing CO2 emissions requires global action, so as ecologists and conservationists, we're are also looking for levers we can pull at the local scale to help coral reef ecosystems withstand these global stressors while we also take action to address climate change."

Pollution

February 24, 2020

https://www.sciencedaily.com/releases/2020/02/200224152713.htm

'Grand Challenge' review stresses global impact of microplastics

Professor Rob Hale of William & Mary's Virginia Institute of Marine Science is lead author of a new "Grand Challenges" paper commissioned to mark the 100th anniversary of the American Geophysical Union, the world's largest association of Earth and space scientists with more than 60,000 members in 137 countries.

The paper, "A Global Perspective on Microplastics," is co-authored by VIMS doctoral student Meredith Seeley and senior research scientist Dr. Mark LaGuardia, along with Drs. Lei Mai and Eddy Zeng of Jinan University in Guangzhou, China."Microplastics" are microscopic particles fabricated for products like facial scrubs, or produced when physical, chemical, and biological forces break down larger pieces of plastic debris. There has been widespread concern among scientists and the public that these minute synthetic fragments are impacting marine ecosystems.AGU Executive Director/CEO Chris McEntee says the Grand Challenges "represent a special collection of open-access review papers with the shared goal of transforming Earth and space science to meet the challenges of today and the opportunities of tomorrow. They explore where major research and discovery are needed to address fundamental questions in our understanding of Earth and the solar system."The team's paper appears in the January issue of the "It's not just an ocean problem," says Hale. "There's growing evidence that microplastics are distributed across the land surface and in the air. We're finally opening up the other boxes and discovering a pretty substantial footprint."Indeed, the broad nature of the microplastic threat is a main focus of the authors' manuscript. "We stress that microplastics are a global phenomenon that can't be adequately understood or addressed in the context of the marine environment alone," says Hale. "Plastics are produced, used, and discarded on land, and disperse through soils, rivers, and the atmosphere. The cat's already out of the bag if you're talking about dealing with these materials after they've reached the ocean."The researchers note that the global scope of the issue extends to the social sphere as well. "We have to recognize that microplastic pollution is an international problem that doesn't respect political boundaries," says Seeley. "As with climate change and species management, developed and emerging nations will have to cooperate to find equitable solutions."A second goal of the article is to gain broader recognition that "plastic" is a catch-all term for a complex array of materials that vary in chemical composition, size, texture, and shape -- including pellets, fragments, and fibers. Adding further complexity is that plastics are often infused with additives, including flame retardants and UV inhibitors, which may themselves have environmental and health impacts."People often assume that all plastics are the same and behave identically in the environment," says Hale, "but that isn't the case at all. To resolve key questions and mitigate possible impacts, everyone -- manufacturers, scientists, health-care specialists, engineers, economists, policymakers, and others -- must collaborate to better understand the composition and nature of plastic products and their additives."The researchers also stress that the characteristics of microplastics can and do change during and after use. "The complexity of microplastics becomes even more convoluted once they enter the environment and begin to intermingle and weather," says LaGuardia. "We have to better understand these complexities, especially in transition zones such as estuaries."To gain that understanding, the authors recommend the research community move beyond studies of individual habitats, size ranges, polymer types, or forms; and into more holistic studies of the changing characteristics of microplastics and their impacts on ecosystem health and processes.The researchers' third main message is that comprehensive understanding of the microplastics issue, and the most effective responses, will require better analytical tools."To understand the real impacts of microplastics," says Hale, "we've got to improve our sampling and analytical capabilities, including the ability to study nanoplastics and weathered materials." Nanoplastics are particles even smaller than microplastics, with sizes ranging from 1 nanometer to 1,000 nanometers or a micron. A strand of DNA is about 2.5 nanometers across.Hale says current state-of-the-art instruments, such as FTIR and Raman microscopes, "provide really great information when you zero in on a single microplastic particle." The problem, he says, is that many samples contain thousands of different particles, and many of these particles are really, really small."There's a disconnect," says Hale. "A lot of our technology can't get down to stuff below 10 microns, and in terms of effects on organisms, we think that smaller particles may be more toxic." Trying to bridge this gap, VIMS recently received funding from the NOAA Marine Debris program to investigate interactions between particles smaller than 10 microns and infectious disease in fish.The authors' concerns regarding microplastics extend to potential impacts on human health."There have been concerns about ingesting microplastics from seafood, but the indoor environment is our biggest direct threat," says Hale. "Many people in developed countries spend almost all their time indoors, in spaces that are increasingly air-tight and insulated with things like polystyrene foam. Our exposure to microplastics from breathing and ingesting indoor dust may have toxicological consequences, but there's been very little research."To address these concerns, Hale and colleagues at VIMS are acquiring a time-of-flight mass spectrometer, which will hopefully allow them to better analyze chemical contaminants associated with microplastics, as well as those found in other environmental samples."This will help us start going after all these unknown additives in plastics and open up that Pandora's Box a little better," says Hale. "I think that's where the action really is in terms of human health."

Pollution

February 20, 2020

https://www.sciencedaily.com/releases/2020/02/200220141710.htm

Old carbon reservoirs unlikely to cause massive greenhouse gas release, study finds

Permafrost in the soil and methane hydrates deep in the ocean are large reservoirs of ancient carbon. As soil and ocean temperatures rise, the reservoirs have the potential to break down, releasing enormous quantities of the potent greenhouse gas methane. But would this methane actually make it to the atmosphere?

Researchers at the University of Rochester -- including Michael Dyonisius, a graduate student in the lab of Vasilii Petrenko, professor of earth and environmental sciences -- and their collaborators studied methane emissions from a period in Earth's history partly analogous to the warming of Earth today. Their research, published in "One of our take-home points is that we need to be more concerned about the anthropogenic emissions -- those originating from human activities -- than the natural feedbacks," Dyonisius says.When plants die, they decompose into carbon-based organic matter in the soil. In extremely cold conditions, the carbon in the organic matter freezes and becomes trapped instead of being emitted into the atmosphere. This forms permafrost, soil that has been continuously frozen -- even during the summer -- for more than one year. Permafrost is mostly found on land, mainly in Siberia, Alaska, and Northern Canada.Along with organic carbon, there is also an abundance of water ice in permafrost. When the permafrost thaws in rising temperatures, the ice melts and the underlying soil becomes waterlogged, helping to create low-oxygen conditions -- the perfect environment for microbes in the soil to consume the carbon and produce methane.Methane hydrates, on the other hand, are mostly found in ocean sediments along the continental margins. In methane hydrates, cages of water molecules trap methane molecules inside. Methane hydrates can only form under high pressures and low temperatures, so they are mainly found deep in the ocean. If ocean temperatures rise, so will the temperature of the ocean sediments where the methane hydrates are located. The hydrates will then destabilize, fall apart, and release the methane gas."If even a fraction of that destabilizes rapidly and that methane is transferred to the atmosphere, we would have a huge greenhouse impact because methane is such a potent greenhouse gas," Petrenko says. "The concern really has to do with releasing a truly massive amount of carbon from these stocks into the atmosphere as the climate continues to warm."In order to determine how much methane from ancient carbon deposits might be released to the atmosphere in warming conditions, Dyonisius and his colleagues turned to patterns in Earth's past. They drilled and collected ice cores from Taylor Glacier in Antarctica. The ice core samples act like time capsules: they contain tiny air bubbles with small quantities of ancient air trapped inside. The researchers use a melting chamber to extract the ancient air from the bubbles and then study its chemical composition.Dyonisius's research focused on measuring the composition of air from the time of Earth's last deglaciation, 8,000-15,000 years ago."The time period is a partial analog to today, when Earth went from a cold state to a warmer state," Dyonisius says. "But during the last deglaciation, the change was natural. Now the change is driven by human activity, and we're going from a warm state to an even warmer state."Analyzing the carbon-14 isotope of methane in the samples, the group found that methane emissions from the ancient carbon reservoirs were small. Thus, Dyonisius concludes, "the likelihood of these old carbon reservoirs destabilizing and creating a large positive warming feedback in the present day is also low."Dyonisius and his collaborators also concluded that the methane released does not reach the atmosphere in large quantities. The researchers believe this is due to several natural "buffers."In the case of methane hydrates, if the methane is released in the deep ocean, most of it is dissolved and oxidized by ocean microbes before it ever reaches the atmosphere. If the methane in permafrost forms deep enough in the soil, it may be oxidized by bacteria that eat the methane, or the carbon in the permafrost may never turn into methane and may instead be released as carbon dioxide."It seems like whatever natural buffers are in place are ensuring there's not much methane that gets released," Petrenko says.The data also shows that methane emissions from wetlands increased in response to climate change during the last deglaciation, and it is likely wetland emissions will increase as the world continues to warm today.Even so, Petrenko says, "anthropogenic methane emissions currently are larger than wetland emissions by a factor of about two, and our data shows we don't need to be as concerned about large methane releases from large carbon reservoirs in response to future warming; we should be more concerned about methane released from human activities."This study was supported by the US National Science Foundation and the David and Lucille Packard Foundation.

Pollution

February 19, 2020

https://www.sciencedaily.com/releases/2020/02/200219184613.htm

Illuminating interactions between decision-making and the environment

In a heavily polluted environment, does it make more sense for a company to keep polluting or start cleaning up its act? If it chooses to employ cleaner technologies and the environment becomes healthier, does the same calculus apply?

These feedbacks between decision strategy and the environment come up in fields as diverse as fisheries, economics, and human social interactions. Game theorists have explored these so-called feedbacks using individual models to apply to particular scenarios. But in a new publication in "What we do in our paper is try to explicitly incorporate the way in which evolutionary game dynamics can be affected by the environment and can change the environment," says Andrew Tilman, first author on the paper and a postdoctoral researcher in the Department of Biology. "So, you get this feedback between strategies that are used in the game and environmental change."Tilman coauthored the work with advisers Erol Akçay and Joshua Plotkin, faculty members whose work specializes in theoretical and computational approaches to biological questions.The findings shed light on the tight-knit forces that link changes in strategic action to environmental change, and vice versa."Take fish stocks that go up or down depending on the fishing strategies of a population, or soil nutrient levels that go up or down depending on whether there are nitrogen fixers or nonfixing plants present," says Akçay. "How much fish or nitrogen there is will then determine the payoffs from different strategies and favor one or the other strategy. This situation crops up everywhere and while there were disparate models here and there, what Andrew did really was to tie it all together in one. He showed that you can map these models onto a common model and then analyze that model and make predictions for a lot of different systems.""Understanding how the balance of strategic types in a population impacts the environment, and how the environment then feeds back to alter strategic interactions, is a new challenge for ecologists and behavioral scientists," says Plotkin. "It's a fun theoretical problem, but it also has a host of implications in applied settings, where we increasingly recognize the tight intercalation of human behaviors and the changing environment."The project arose from Tilman's doctoral work, which looked at the economic incentives people face when dealing with a common-pool resource, for example a fishery or healthy environment."I was doing it in an ad hoc way, putting together a model of environmental dynamics with an evolutionary game-theory model for each one," he says. "I was inspired to work on a way to unite many different problems that are all thinking about these strategic interactions linked with a changing environment."The researchers found that a relatively simple linear model could map the dynamics of a variety of these types of strategy-environment feedbacks."We created some nonlinear models as well, and some nuances can arise, but the linear models give you intuition for why those new things can happen," says Akçay. "They're surprisingly powerful."Their analysis worked for systems like a pollution example, where environmental impact -- more pollution -- fades as time passes. But the model also fit scenarios where the environmental product regenerated, as in a fisheries example.The model enabled them to predict how strategies would change, whether they would cycle or achieve an equilibrium, based on the incentives faced by the actors when both the environmental conditions and the strategies in a population were at an extreme. Again turning to the pollution model: "You could imagine that one strategy would be to emit high levels of pollution, and another would be to emit low levels of pollution, and depending on the mix of strategies being used, it will impact the level of pollution that's present," Tilman says. "We can understand what will happen in the game based on how strong the incentives are to switch to a high-pollution strategy when the environment is in a low-pollution state as well as the incentives to switch to a high-polluting strategy when the environment is in a low-polluting state."The approach sheds light on contemporary issues, such as regulating global emissions in the face of climate change."We see that if everything is clean, you want to kill any incentive to be a polluter. Otherwise the cycle could tip back toward polluting strategies," says Akçay.Looking ahead, the researchers hope to incorporate forecasting into their model. In other words, if an actor can predict how the environment will change, will they alter their strategies earlier or later than they would otherwise?"These evolutionary and game theoretic models tend to consider the actors to be myopic, switching their strategies based on their instantaneous incentives," says Tilman. "But to more realistically mimic the decision-making processes that people engage in, we want to start thinking about incorporating forecasting into the modeling framework."

Pollution

February 19, 2020

https://www.sciencedaily.com/releases/2020/02/200219113746.htm

Methane emitted by humans vastly underestimated

Methane is a powerful greenhouse gas and large contributor to global warming. Methane emissions to the atmosphere have increased by approximately 150 percent over the past three centuries, but it has been difficult for researchers to determine exactly where these emissions originate; heat-trapping gases like methane can be emitted naturally, as well as from human activity.

University of Rochester researchers Benjamin Hmiel, a postdoctoral associate in the lab of Vasilii Petrenko, a professor of earth and environmental sciences, and their collaborators, measured methane levels in ancient air samples and found that scientists have been vastly underestimating the amount of methane humans are emitting into the atmosphere via fossil fuels. In a paper published in "Placing stricter methane emission regulations on the fossil fuel industry will have the potential to reduce future global warming to a larger extent than previously thought," Hmiel says.Methane is the second largest anthropogenic -- originating from human activity -- contributor to global warming, after carbon dioxide. But, compared to carbon dioxide, as well as other heat-trapping gases, methane has a relatively short shelf-life; it lasts an average of only nine years in the atmosphere, while carbon dioxide, for instance, can persist in the atmosphere for about a century. That makes methane an especially suitable target for curbing emission levels in a short time frame."If we stopped emitting all carbon dioxide today, high carbon dioxide levels in the atmosphere would still persist for a long time," Hmiel says. "Methane is important to study because if we make changes to our current methane emissions, it's going to reflect more quickly."Methane emitted into the atmosphere can be sorted into two categories, based on its signature of carbon-14, a rare radioactive isotope. There is fossil methane, which has been sequestered for millions of years in ancient hydrocarbon deposits and no longer contains carbon-14 because the isotope has decayed; and there is biological methane, which is in contact with plants and wildlife on the planet's surface and does contain carbon-14. Biological methane can be released naturally from sources such as wetlands or via anthropogenic sources such as landfills, rice fields, and livestock. Fossil methane, which is the focus of Hmiel's study, can be emitted via natural geologic seeps or as a result of humans extracting and using fossil fuels including oil, gas, and coal.Scientists are able to accurately quantify the total amount of methane emitted to the atmosphere each year, but it is difficult to break down this total into its individual components: Which portions originate from fossil sources and which are biological? How much methane is released naturally and how much is released by human activity?"As a scientific community we've been struggling to understand exactly how much methane we as humans are emitting into the atmosphere," says Petrenko, a coauthor of the study. "We know that the fossil fuel component is one of our biggest component emissions, but it has been challenging to pin that down because in today's atmosphere, the natural and anthropogenic components of the fossil emissions look the same, isotopically."In order to more accurately separate the natural and anthropogenic components, Hmiel and his colleagues turned to the past, by drilling and collecting ice cores from Greenland. The ice core samples act like time capsules: they contain air bubbles with small quantities of ancient air trapped inside. The researchers use a melting chamber to extract the ancient air from the bubbles and then study its chemical composition.Hmiel's research focused on measuring the composition of air from the early 18th century -- before the start of the Industrial Revolution -- to the present day. Humans did not begin using fossil fuels in significant amounts until the mid-19th century. Measuring emission levels before this time period allows researchers to identify the natural emissions absent the emissions from fossil fuels that are present in today's atmosphere. There is no evidence to suggest natural fossil methane emissions can vary over the course of a few centuries.By measuring the carbon-14 isotopes in air from more than 200 years ago, the researchers found that almost all of the methane emitted to the atmosphere was biological in nature until about 1870. That's when the fossil component began to rise rapidly. The timing coincides with a sharp increase in the use of fossil fuels.The levels of naturally released fossil methane are about 10 times lower than previous research reported. Given the total fossil emissions measured in the atmosphere today, Hmiel and his colleagues deduce that the manmade fossil component is higher than expected -- 25-40 percent higher, they found.The data has important implications for climate research: if anthropogenic methane emissions make up a larger part of the total, reducing emissions from human activities like fossil fuel extraction and use will have a greater impact on curbing future global warming than scientists previously thought.To Hmiel, that's actually good news. "I don't want to get too hopeless on this because my data does have a positive implication: most of the methane emissions are anthropogenic, so we have more control. If we can reduce our emissions, it's going to have more of an impact."This study was supported by the US National Science Foundation and the David and Lucille Packard Foundation.

Pollution

February 18, 2020

https://www.sciencedaily.com/releases/2020/02/200218124405.htm

Do the climate effects of air pollution impact the global economy?

Aerosol emissions from burning coal and wood are dangerous to human health, but it turns out that by cooling the Earth they also diminish global economic inequality, according to a new study by Carnegie's Yixuan Zheng, Geeta Persad, and Ken Caldeira, along with UC Irvine's Steven Davis. Their findings are published by

Tiny particles spewed into the atmosphere by human activity, called "anthropogenic aerosols," interact with clouds and reflect some of the Sun's energy back into space. They have a short-term cooling effect that's similar to how particles from major volcanic eruptions can cause global temperatures to drop. This masks some of the warming caused by much-longer-lived greenhouse gases, which trap the Sun's heat in the planet's atmosphere."Estimates indicate that aerosol pollution emitted by humans is offsetting about 0.7 degrees Celsius, or about 1.3 degrees Fahrenheit, of the warming due to greenhouse gas emissions," said lead author Zheng. "This translates to a 40-year delay in the effects of climate change. Without cooling caused by aerosol emissions, we would have achieved 2010-level global mean temperatures in 1970."Previous research has shown that climate change provides some economic benefits to countries in cool regions -- which would be warmed to temperatures that are ideal for agricultural productivity and human labor -- and economic harm to countries in already hot regions.Does aerosol-related cooling have a similar distribution of economic impacts?The four researchers set out to investigate the economic effects of cooling caused by aerosol emissions in different parts of the world. They found that, opposite to greenhouse gases, the cooling effect of aerosols benefitted the economies of tropical, developing countries and harmed the economies of high latitude, developed countries."Although aerosols have many negative impacts, our simulations demonstrated that aerosol-induced cooling, in particular, could actually diminish global economic inequality," Persad said."However, when you look at the whole world at once, rather than region by region, the net economic effect of this cooling is likely to be small due to these effects between latitudes," added Davis.Despite this, the team noted that aerosols are dangerous and that the public health benefits of cleaning them up would far outweigh the economic benefits of continuing to release them."We need to understand how human activities affect our planet so we can make informed decisions that can protect the environment while giving everyone a high quality of life," Caldeira concluded. "Aerosol pollution might appear to have some upsides, but at the end of the day their profound harm far outweighs their meager benefits."

Pollution

February 18, 2020

https://www.sciencedaily.com/releases/2020/02/200218124358.htm

Warming, acidic oceans may nearly eliminate coral reef habitats by 2100

Rising sea surface temperatures and acidic waters could eliminate nearly all existing coral reef habitats by 2100, suggesting restoration projects in these areas will likely meet serious challenges, according to new research presented in San Diego at the Ocean Sciences Meeting 2020.

Scientists project 70 to 90 percent of coral reefs will disappear over the next 20 years as a result of climate change and pollution. Some groups are attempting to curb this decline by transplanting live corals grown in a lab to dying reefs. They propose new, young corals will boost the reef's recovery and bring it back to a healthy state.But new research mapping where such restoration efforts would be most successful over the coming decades finds that by 2100, few to zero suitable coral habitats will remain. The preliminary findings suggest sea surface temperature and acidity are the most important factors in determining if a site is suitable for restoration."By 2100, it's looking quite grim," said Renee Setter, a biogeographer at the University of Hawaii Manoa who will present the new findings.The results highlight some of the devastating impacts Earth's warming climate will have on marine life, according to the researchers. Although pollution poses numerous threats to ocean creatures, the new research suggests corals are most at risk from emission-driven changes in their environment."Trying to clean up the beaches is great and trying to combat pollution is fantastic. We need to continue those efforts," Setter said. "But at the end of the day, fighting climate change is really what we need to be advocating for in order to protect corals and avoid compounded stressors."Coral reefs around the globe face uncertain futures as ocean temperatures continue to climb. Warmer waters stress corals, causing them to release symbiotic algae living inside them. This turns typically vibrant-colored communities of corals white, a process called bleaching. Bleached corals are not dead, but they are at higher risk of dying, and these bleaching events are becoming more common under climate change.In the new study, Setter and her colleagues mapped what areas of the ocean would be suitable for coral restoration efforts over the coming decades. The researchers simulated ocean environment conditions like sea surface temperature, wave energy, acidity of the water, pollution, and overfishing in areas where corals now exist. To factor in pollution and overfishing, the researchers considered human population density and land cover use to project how much waste would be released into the surrounding waters.The researchers found most of parts of the ocean where coral reefs exist today won't be suitable habitats for corals by 2045, and the situation worsened as the simulation extended to 2100."Honestly, most sites are out," Setter said. The few sites that are viable by 2100 included only small portions of Baja California and the Red Sea, which are not ideal locations for coral reefs because of their proximity to rivers.Rising temperatures and ocean acidification are mostly to blame for diminishing coral habitats, according to the researchers. Projected increases in human pollution have only a minor contribution to the future elimination of reef habitat, because humans have already caused such extensive damage to coral reefs that there aren't many locations left to impact, Setter said.

Pollution

February 17, 2020

https://www.sciencedaily.com/releases/2020/02/200217112736.htm

Freshwater insects recover while spiders decline in UK

Many insects, mosses and lichens in the UK are bucking the trend of biodiversity loss, according to a comprehensive analysis of over 5,000 species led by UCL and the UK Centre for Ecology & Hydrology (UKCEH).

The researchers say their findings on UK biodiversity between 1970 and 2015, published in "By looking at long-term trends in the distribution of understudied species, we found evidence of concerning declines, but we also found that it's not all bad news. Some groups of species, particularly freshwater insects, appear to be undergoing a strong recovery," said the study's lead author, Dr Charlie Outhwaite (UCL Centre for Biodiversity & Environment Research, UK Centre for Ecology & Hydrology, and the RSPB).Funded by the Natural Environment Research Council (NERC), the researchers analysed trends in the distribution of invertebrates (such as insects and spiders), bryophytes (such as mosses) and lichens over a 45-year period, to see whether they were following the same declining trends reported in better-studied groups such as mammals, birds and butterflies.Across all 5,214 species surveyed, overall occupancy (distribution) was 11% higher in 2015 than in 1970. The researchers were not able to estimate the total numbers of each species, but gauged how well each species was doing by whether its geographic range was expanding or shrinking.They found substantial variation between the different groups, and between individual species within each group. Among the four major groups studied, only one of them -- terrestrial non-insect invertebrates (mainly spiders, centipedes and millipedes) -- exhibited an overall trend of declining distribution (by 7% since 1970).More positively, freshwater insects, such as mayflies, dragonflies and caddisflies, have undergone a strong recovery since the mid-1990s, recently surpassing 1970 levels following a 47% decline from 1970 to 1994. Mosses and lichens have also increased in average occupancy (distribution) by 36%, while terrestrial insects, such as ants and moths, exhibited a slight increase.The data included over 24 million records, each identifying a sighting of a particular species in a particular location, sourced from numerous biological recording schemes. People from across the UK have been contributing to the recording schemes on a volunteer basis for decades.While the volunteers used inconsistent methods to collect their records, having such a vast quantity of data enabled the researchers to analyse it effectively using occupancy modelling techniques."Our study demonstrates the power of citizen science, as anyone can contribute to impactful academic research. We couldn't have done this research without the hard work of thousands of volunteers who have contributed to recording schemes over the years," said Dr Outhwaite.While the study period only went back to 1970, other research suggests that many of the species studied would have been experiencing long-term declines dating back to the industrial revolution or further, due to pollution or habitat losses from agricultural expansion and urbanisation.While they did not investigate the particular reasons for the declines and recoveries found in this study, the researchers say that it's likely that environmental protection initiatives are helping some species recover. Mosses and lichens are known to be susceptible to air pollution, while freshwater insects likely benefited from improvements in waste water treatment since the early 1990s.

Pollution

February 17, 2020

https://www.sciencedaily.com/releases/2020/02/200217112730.htm

New green technology generates electricity 'out of thin air'

Scientists at the University of Massachusetts Amherst have developed a device that uses a natural protein to create electricity from moisture in the air, a new technology they say could have significant implications for the future of renewable energy, climate change and in the future of medicine.

As reported today in "We are literally making electricity out of thin air," says Yao. "The Air-gen generates clean energy 24/7." Lovely, who has advanced sustainable biology-based electronic materials over three decades, adds, "It's the most amazing and exciting application of protein nanowires yet."The new technology developed in Yao's lab is non-polluting, renewable and low-cost. It can generate power even in areas with extremely low humidity such as the Sahara Desert. It has significant advantages over other forms of renewable energy including solar and wind, Lovley says, because unlike these other renewable energy sources, the Air-gen does not require sunlight or wind, and "it even works indoors."The Air-gen device requires only a thin film of protein nanowires less than 10 microns thick, the researchers explain. The bottom of the film rests on an electrode, while a smaller electrode that covers only part of the nanowire film sits on top. The film adsorbs water vapor from the atmosphere. A combination of the electrical conductivity and surface chemistry of the protein nanowires, coupled with the fine pores between the nanowires within the film, establishes the conditions that generate an electrical current between the two electrodes.The researchers say that the current generation of Air-gen devices are able to power small electronics, and they expect to bring the invention to commercial scale soon. Next steps they plan include developing a small Air-gen "patch" that can power electronic wearables such as health and fitness monitors and smart watches, which would eliminate the requirement for traditional batteries. They also hope to develop Air-gens to apply to cell phones to eliminate periodic charging.Yao says, "The ultimate goal is to make large-scale systems. For example, the technology might be incorporated into wall paint that could help power your home. Or, we may develop stand-alone air-powered generators that supply electricity off the grid. Once we get to an industrial scale for wire production, I fully expect that we can make large systems that will make a major contribution to sustainable energy production."Continuing to advance the practical biological capabilities of Geobacter, Lovley's lab recently developed a new microbial strain to more rapidly and inexpensively mass produce protein nanowires. "We turned E. coli into a protein nanowire factory," he says. "With this new scalable process, protein nanowire supply will no longer be a bottleneck to developing these applications."The Air-gen discovery reflects an unusual interdisciplinary collaboration, they say. Lovley discovered the Geobacter microbe in the mud of the Potomac River more than 30 years ago. His lab later discovered its ability to produce electrically conductive protein nanowires. Before coming to UMass Amherst, Yao had worked for years at Harvard University, where he engineered electronic devices with silicon nanowires. They joined forces to see if useful electronic devices could be made with the protein nanowires harvested from Geobacter.Xiaomeng Liu, a Ph.D. student in Yao's lab, was developing sensor devices when he noticed something unexpected. He recalls, "I saw that when the nanowires were contacted with electrodes in a specific way the devices generated a current. I found that that exposure to atmospheric humidity was essential and that protein nanowires adsorbed water, producing a voltage gradient across the device."In addition to the Air-gen, Yao's laboratory has developed several other applications with the protein nanowires. "This is just the beginning of new era of protein-based electronic devices" said Yao.The research was supported in part from a seed fund through the Office of Technology Commercialization and Ventures at UMass Amherst and research development funds from the campus's College of Natural Sciences.

Pollution

February 14, 2020

https://www.sciencedaily.com/releases/2020/02/200214134717.htm

Air pollution's tiny particles may trigger nonfatal heart attacks

Yale-affiliated scientist finds that even a few hours' exposure to ambient ultrafine particles common in air pollution may potentially trigger a nonfatal heart attack.

Myocardial infarction is a major form of cardiovascular disease worldwide. Ultrafine particles (UFP) are 100 nanometers or smaller in size. In urban areas, automobile emissions are the primary source of UFP.The study in the journal "This study confirms something that has long been suspected -- air pollution's tiny particles can play a role in serious heart disease. This is particularly true within the first few hours of exposure," said Kai Chen, Ph.D., assistant professor at Yale School of Public Health and the study's first author. "Elevated levels of UFP are a serious public health concern."UFP constitute a health risk due to their small size, large surface areas per unit of mass, and their ability to penetrate the cells and get into the blood system. "We were the first to demonstrate the effects of UFP on the health of asthmatics in an epidemiological study in the 1990s," said Annette Peters, director of the Institute of Epidemiology at Helmholtz Center Munich and a co-author of this paper. "Since then approximately 200 additional studies have been published. However, epidemiological evidence remains inconsistent and insufficient to infer a causal relationship."The lack of consistent findings across epidemiological studies may be in part because of the different size ranges and exposure metrics examined to characterize ambient UFP exposure. Chen and his co-authors were interested in whether transient UFP exposure could trigger heart attacks and whether alternative metrics such as particle length and surface area concentrations could improve the investigation of UFP-related health effects.With colleagues from Helmholtz Center Munich, Augsburg University Hospital and Nördlingen Hospital, Chen examined data from a registry of all nonfatal MI cases in Augsburg, Germany. The study looked at more than 5, 898 nonfatal heart attack patients between 2005 and 2015. The individual heart attacks were compared against air pollution UFP data on the hour of the heart attack and adjusted for a range of additional factors, such as the day of the week, long-term time trend and socioeconomic status."This represents an important step toward understanding the appropriate indicator of ultrafine particles exposure in determining the short-term health effects, as the effects of particle length and surface concentrations were stronger than the ones of particle number concentration and remained similar after adjustment for other air pollutants," said Chen. "Our future analyses will examine the combined hourly exposures to both air pollution and extreme temperature. We will also identify vulnerable subpopulations regarding pre-existing diseases and medication intake."

Pollution

February 12, 2020

https://www.sciencedaily.com/releases/2020/02/200212150202.htm

New study shows Deepwater Horizon oil spill larger than previously thought

Toxic and invisible oil spread well beyond the known satellite footprint of the Deepwater Horizon oil spill, according to a new study led by scientists at the University of Miami (UM) Rosenstiel school of Marine and Atmospheric Science. These new findings have important implications for environmental health during future oil spills.

The UM Rosenstiel School-led research team combine oil-transport modeling techniques with remote sensing data and in-water sampling to provide a comprehensive look at the oil spill. The findings revealed that a fraction of the spill was invisible to satellites, and yet toxic to marine wildlife."We found that there was a substantial fraction of oil invisible to satellites and aerial imaging," said the study's lead author Igal Berenshtein, a postdoctoral researcher at the UM Rosenstiel School. "The spill was only visible to satellites above a certain oil concentration at the surface leaving a portion unaccounted for."On April 20, 2010, the Deepwater Horizon oil rig exploded, releasing 210 million gallons of crude oil into the Gulf of Mexico for a total of 87 days, making it the largest oil spill in U.S. history. Oil slicks from the blowout covered an estimated area of 57,000 square miles (149,000 square kilometers).These new findings, published in "Our results change established perceptions about the consequences of oil spills by showing that toxic and invisible oil can extend beyond the satellite footprint at potentially lethal and sub-lethal concentrations to a wide range of wildlife in the Gulf of Mexico," said Claire Paris, senior author of the study and professor of ocean sciences the UM Rosenstiel School. "This work added a 3rd dimension to what was previously seen as just surface slicks. This additional dimension has been visualized with more realistic and accurate oil spill models developed with a team of chemical engineers and more efficient computing resources."The new framework developed by the researchers can assist emergency managers and decision makers in better managing the impacts of future potential oil spills, said the authors.The study, titled "Invisible oil beyond the Deepwater Horizon satellite footprint," was published on February 12, 2020 in the journal

Pollution

February 12, 2020

https://www.sciencedaily.com/releases/2020/02/200212131520.htm

Half of US deaths related to air pollution are linked to out-of-state emissions

More than half of all air-quality-related early deaths in the United States are a result of emissions originating outside of the state in which those deaths occur, MIT researchers report in the journal

The study focuses on the years between 2005 and 2018 and tracks combustion emissions of various polluting compounds from various sectors, looking at every state in the contiguous United States, from season to season and year to year.In general, the researchers find that when air pollution is generated in one state, half of that pollution is lofted into the air and carried by winds across state boundaries, to affect the health quality of out-of-state residents and increase their risk of early death.Electric power generation is the greatest contributor to out-of-state pollution-related deaths, the findings suggest. In 2005, for example, deaths caused by sulfur dioxide emitted by power plant smokestacks occurred in another state in more than 75 percent of cases.Encouragingly, the researchers found that since 2005, early deaths associated with air pollution have gone down significantly. They documented a decrease of 30 percent in 2018 compared to 2005, equivalent to about 30,000 avoided early deaths, or people who did not die early as a result of pollution. In addition, the fraction of deaths that occur due to emissions in other states is falling -- from 53 percent in 2005 to 41 percent in 2018.Perhaps surprisingly, this reduction in cross-state pollution also appears to be related to electric power generation: In recent years, regulations such as the Environmental Protection Agency's Clean Air Act and other changes have helped to significantly curb emissions from this sector across the country.The researchers caution, however, that today, emissions from other sectors are increasingly contributing to harmful cross-state pollution."Regulators in the U.S. have done a pretty good job of hitting the most important thing first, which is power generation, by reducing sulfur dioxide emissions drastically, and there's been a huge improvement, as we see in the results," says study leader Steven Barrett, an associate professor of aeronautics and astronautics at MIT. "Now it's looking like other emissions sectors are becoming important. To make further progress, we should start focusing on road transportation and commercial and residential emissions."Barrett's coauthors on the paper are Sebastian Eastham, a research scientist at MIT; Irene Dedoussi, formerly an MIT graduate student and now an assistant professor at Delft University of Technology; and Erwan Monier, formerly an MIT research scientist and now an assistant professor at the University of California at Davis. The research was a collaboration between MIT's Laboratory for Aviation and the Environment and the MIT Joint Program on the Science and Policy of Global Change.Scientists have long known that pollution observes no boundaries, one of the prime examples being acid rain."It's been known in Europe for over 30 years that power stations in England would create acid rain that would affect vegetation in Norway, but there's not been a systematic way to capture how that translates to human health effects," Barrett says.In the case of the United States, tracking how pollution from one state affects another state has historically been tricky and computationally difficult, Barrett says. For each of the 48 contiguous states, researchers would have to track emissions to and from the rest of the 47 states."But now there are modern computational tools that enable you to do these assessments in a much more efficient way," Barrett says. "That wasn't really possible before."He and his colleagues developed such tools, drawing on fundamental work by Daven Henze at the University of Colorado at Boulder, to track how every state in the contiguous U.S. affects pollution and health outcomes in every other state. They looked at multiple species of pollutants, such as sulfur dioxide, ozone, and fine particulates, from various emissions sectors, including electric power generation, road transportation, marine, rail, and aviation, and commercial and residential sources, at intervals of every hour of the year.They first obtained emissions data from each of seven sectors for the years 2005, 2011, and 2018. They then used the GEOS-Chem atmospheric chemistry transport model to track where these emissions ended up, from season to season and year to year, based on wind patterns and a pollutant's chemical reactions to the atmosphere. Finally, they used an epidemiologically derived model to relate a population's pollutant exposure and risk of early death."We have this multidimensional matrix that characterizes the impact of a state's emissions of a given economic sector of a given pollutant at a given time, on any other state's health outcomes," Barrett says. "We can figure out, for example, how much NOx emissions from road transportation in Arizona in July affects human health in Texas, and we can do those calculations instantly."The researchers also found that emissions traveling out of state could affect the health of residents beyond immediate, neighboring states."It's not necessarily just the adjacent state, but states over 1,000 miles away that can be affected," Barrett says. "Different kinds of emissions have a different kind of range."For example, electric power generation has the greatest range, as power plants can loft pollutants far into the atmosphere, allowing them to travel over long distances. In contrast, commercial and residential sectors generally emit pollutants that chemically do not last as long in the atmosphere."The story is different for each pollutant," Barrett says.In general, the researchers found that out-of-state air pollution was associated with more than half of all pollution-related early deaths in the U.S. from 2005 to 2018.In terms of the impact on individual states, the team found that many of the northern Midwest states such as Wyoming and North Dakota are "net exporters" of pollution-related health impacts, partly because the populations there are relatively low and the emissions these states generate are carried away by winds to other states. Those states that "import" health impacts tend to lie along the East Coast, in the path of the U.S. winds that sweep eastward.New York in particular is what the researchers call "the biggest importer of air pollution deaths"; 60 percent of air pollution-related early deaths are from out-of-state emissions."There's a big archive of data we've created from this project," Barrett says. "We think there are a lot of things that policymakers can dig into, to chart a path to saving the most lives."This research was supported, in part, by the U.S. Environmental Protection Agency, the MIT Martin Family Fellowship for Sustainability, and the George and Marie Vergottis Fellowship at MIT.

Pollution

February 12, 2020

https://www.sciencedaily.com/releases/2020/02/200212104735.htm

How roots find their way to water

Plants use their roots to search for water. While the main root digs down-wards, a large number of fine lateral roots explore the soil on all sides. As researchers from Nottingham, Heidelberg and Goethe University of Frankfurt report in the current issue of

For his experiment, Daniel von Wangenheim, a former doctoral researcher in Professor Ernst Stelzer's Laboratory for Physical Biology and most lately a postdoc at Malcolm Ben-nett's, mounted thale cress roots along their length in a nutrient solution. They were, how-ever, not completely immersed and their upper side left exposed to the air. He then ob-served with the help of a high-resolution 3D microscope how the roots branched out.To his surprise, he discovered that almost as many lateral roots formed on the air side as on the side in contact with the nutrient solution. As he continued to follow the growth of the roots with each cell division in the microscope, it became evident that the new cells drive the tip of the root in the direction of water from the very outset, meaning that if a lateral root had formed on the air side, it grew in the direction of the agar plate."It's therefore clear that plants first of all spread their roots in all directions, but the root obvi-ously knows from the very first cell divisions on where it can find water and nutrients," says Daniel von Wangenheim, summarizing the results. "In this way, plants can react flexibly to an environment with fluctuating resources."

Pollution

February 11, 2020

https://www.sciencedaily.com/releases/2020/02/200211134538.htm

Hot climates to see more variability in tree leafing as temperatures rise

A team of scientists led by Oak Ridge National Laboratory found that while all regions of the country can expect an earlier start to the growing season as temperatures rise, the trend is likely to become more variable year-over-year in hotter regions.

The researchers examined satellite imagery, air temperature data and phenology (plant life cycle} models for 85 large cities and their surrounding rural areas from 2001 through 2014 to better understand changes in tree leaf emergence, also called budburst, on a broad scale across the United States. The study can help scientists improve their modeling of the potential impacts of future warming.The results are detailed in an article in the In all areas, whether with a cold, medium or hot climate to begin with, tree budburst happened earlier as temperatures trended higher. The analysis found that the link between early budburst and temperature was most pronounced in cities with intense urban heat islands -- areas characterized by significantly higher air temperatures vs. adjacent regions."Even in varied environments, the results for these 85 cities were largely consistent, providing robust evidence of urban warming's impacts on spring phenology," said Jiafu Mao, who led the project at ORNL.During the period under study, the scientists found several interesting trends and potential implications depending on whether the climate was cold or hot at the start."The key finding is that if you start in a cold climate, you end up with more stability from year to year," said Peter Thornton, leader of the Terrestrial Systems Modeling Group in ORNL's Environmental Sciences Division. Conversely, in warmer climates the start-of-season tended to be more variable year over year, he noted."Seasonal temperatures aren't consistent every year; they vary even as the trend is for warming overall," Thornton said. "So one of the things we looked at is how sensitive plant phenology is to those up-and-down, yearly variations. Does the start-of-season change a lot each year as the temperature changes, or does it change a little bit?"There may be other factors at play in long-term phenology changes, the researchers said, including precipitation and humidity levels, whether trees are getting the "chilling" they need in the winter to end their dormancy as expected, and even the impact of nighttime light pollution in large cities."The contrasting results of spring phenology in cold vs. warm regions was very interesting and surprising," Mao said. "It suggests that phenological changes under future warming will depend on geographical location and background climate, and thus different modeling strategies should be considered."The latest research fills the need for more detailed diagnostics that can be plugged into Earth system models in order to help scientists better understand and predict environmental changes. The results of the phenology study are being fed into DOE's Energy Exascale Earth System Model (E3SM) to refine and develop next-generation models of phenology-climate feedbacks."Our current implementation in the Earth system model of how these phenological changes in the start of the season respond to warming is very simplistic," Thornton noted. "Everything kind of behaves the same. But these data suggest that the real world is a lot more complicated than that. It makes a difference whether you start out in a warm climate or a cold climate."We shouldn't expect all parts of the country or all parts of the world to respond similarly, and we need to incorporate that complexity within our model to get the best possible predictions for the future," Thornton said.The project builds on ORNL's research in this area which previously found, for instance, a positive link between human activity and enhanced vegetation growth on a continental scale in the Northern Hemisphere.

Pollution

February 10, 2020

https://www.sciencedaily.com/releases/2020/02/200210153343.htm

Himalayan glacier shows evidence of start of Industrial Revolution

Human beings altered one of the highest peaks in the Himalayas hundreds of years before a person ever set foot there, new research has found.

The study, publishing today in the "The Industrial Revolution was a revolution in the use of energy," said Paolo Gabrielli, lead author of the study and a principal investigator and research scientist at The Ohio State University Byrd Polar and Climate Research Center and the School of Earth Sciences."And so the use of coal combustion also started to cause emissions that we think were transported by winds up to the Himalayas."The research team that published this study was part of a larger international team that traveled to Dasuopu in 1997 to drill ice cores from the glacier. The cores provide a record of snowfall, atmospheric circulation and other environmental changes over time; the Byrd Center has one of the largest collections of ice cores in the world.Dasuopu -- at 7,200 meters or 23,600 feet above sea level -- is the highest-altitude site in the world where scientists have obtained a climate record from an ice core. Dasuopu is located on Shishapangma, one of the world's 14 tallest mountains, which are all located in the Himalayas.For this study, the research team analyzed one core taken from Dasuopu in 1997 for 23 trace metals.The ice cores operate as a sort of timeline, and show new ice forming in layers on the glacier over time. It is possible for researchers to tell almost the precise year a layer of the glacier formed because of environmental clues like snowfall or other known natural or human-made disasters. The ice the researchers evaluated formed between 1499 and 1992, the team determined. Their goal was to see whether human activity had affected the ice in any way, and, if so, when the effects had begun.Their analysis showed it had: The team found higher-than-natural levels of a number of toxic metals, including cadmium, chromium, nickel and zinc, in the ice starting at around 1780 -- the very start of the Industrial Revolution in the United Kingdom. Those metals are all byproducts of burning coal, a key part of industry at the end of the 18th century and throughout the 19th and 20th centuries.The researchers found that those metals were likely transported by winter winds, which travel around the globe from west to east.They also believe it is possible that some of the metals, most notably zinc, came from large-scale forest fires, including those used in the 1800s and 1900s to clear trees to make way for farms."What happens is at that time, in addition to the Industrial Revolution, the human population exploded and expanded," Gabrielli said. "And so there was a greater need for agricultural fields -- and, typically, the way they got new fields was to burn forests."Burning trees adds metals, primarily zinc, to the atmosphere. Gabrielli said it is difficult to tell whether the glacial contamination comes from human-made or natural forest fires. And there are few high-altitude records of large-scale fires from around the world, making that contamination more difficult to track.The contamination in the ice core records was most intense from about 1810 to 1880, the scientists' analysis found. Gabrielli said that is likely because winters were wetter than normal in Dasuopu during that time period, meaning more ice and snow formed. That ice and snow, he said, would have been contaminated by fly ash from the burning of coal or trees that made its way into the westerly winds -- and greater quantities of contaminated ice and snow means more contamination on the glacier.Noteworthy to Gabrielli was that the contamination appeared long before humans scaled the mountains around Dasuopu. The first mountain climbers reached the summit of Mount Everest, at 29,029 feet the world's highest peak above sea level, in 1953. Shishapangma, at 26,335 feet the 14th-highest peak in the world, was first climbed in 1964. The Dasuopo glacier drilling site is about 2,700 feet below the summit.Gabrielli said it is also important to note the difference between "contamination" and "pollution.""The levels of metals we found were higher than what would exist naturally, but were not high enough to be acutely toxic or poisonous," he said. "However, in the future, bioaccumulation may concentrate metals from meltwater at dangerous toxic levels in the tissues of organisms that live in ecosystems below the glacier."This study shows that human activity altered the atmosphere in the Himalayas starting at the end of the 18th century. But a previous study Byrd Polar Center researchers published in 2015 showed that in other parts of the world, namely Peru, human mining for silver contaminated the air in South America as many as 240 years before the Industrial Revolution."What is emerging from our studies, both in Peru and in the Himalayas, is that the impact of humans started at different times in different parts of the planet," Gabrielli said.

Pollution

February 10, 2020

https://www.sciencedaily.com/releases/2020/02/200210153332.htm

Impact of oil contaminated water on tubeworms and brittlestars

A new study published by Dauphin Island Sea Lab researchers adds a new layer to understanding how an oil spill could impact marine life.

A diverse community of worms and other marine organisms on the seafloor plays a significant role in nutrient cycling, organic matter burial, and remineralization. The burrowing and feeding activities of these organisms, or bioturbation, helps in the oxygenation of the sediment.The research team, led by Dr. Kelly Dorgan, conducted a mesocosm experiment to investigate how sublethal levels of oil contamination in seawater may affect animals that live in marine sediments. The mesocosm is a flowthrough facility with tanks large enough to include the elements of field realism, but small enough to control some factors.The research exposed tube worms and brittlestars to seawater that had been mixed and contaminated with oil but had the oil solids removed. These taxa are abundant in the northern Gulf of Mexico. They are both surface deposit feeders. The tubeworm builds its tube from shell fragments and can move vertically and laterally within the sediment. The tube sits about an inch above the sediment allowing the worm to bend the tube and feed on surface sediments. The brittlestar burrows, positioning its oral disk within an inch of the surface. A brittlestar's arms extend above the surface to collect sediment on tube feet.To the research team's knowledge, these taxa had not been previously evaluated for responses to hydrocarbon exposure.Overall, it was determined there was little direct response of sediment animals to oil-contaminated water. It's believed they would be more susceptible to sediment contamination. Notably, the metrics used in this study are broadly applicable to sediment-dwelling animals and could be usefully applied to future exposure studies.Dorgan and her team introduced a novel method to quantify horizontal bioturbation and believe it will be a helpful tool in understanding how marine animals mix sediments. They measured bioturbation using luminophores, which are fluorescent sediment grains that glow when illuminated. Luminophores have been used to measure vertical bioturbation before; however, in this study, the researchers also estimated horizontal clumping/dispersion using tools from spatial analysis. They found differences in both horizontal and vertical mixing between the two species studied.

Pollution

February 12, 2020

https://www.sciencedaily.com/releases/2020/02/200212103024.htm

Microplastics are new homes for microbes in the Caribbean

With 5 trillion pieces of plastic in the oceans, the dynamics of marine environments are shifting in ways that are yet to be discovered. Over time discarded plastics, such as sandwich bags and flip-flops, have degraded into small particles, called microplastics, which are less than 5 mm long. Kassandra Dudek, a former Smithsonian Tropical Research Institute (STRI) fellow and doctoral student at Arizona State University, looked at how marine microbial communities colonize microplastics in Panama.

She took the six common plastic types found in most household items, such as water bottles or milk cartons, and cut them into tiny pieces before submerging them in the tropical waters of Almirante Bay, at STRI's Bocas del Toro Research Station. Since Panama acts as a catch basin for marine debris in the Caribbean due to its geography and interaction with oceanic currents, it is a prime location for the study of plastic pollution."The major goal of the study was to assess differences among plastic types, and I wanted to ensure these plastics were also environmentally relevant," Dudek said. "Consumer items found in everyday households are the plastics polluting our beaches and oceans. It is estimated that roughly 4.8 -- 12.7 million tons of plastic enter the marine environment annually."After a month and a half, she noted that marine bacteria were not picky about the surfaces where they chose to settle. They formed biofilms -- buildups of bacteria -- on all plastic types, using them as artificial reefs and creating 'plastispheres,' a type of ecosystem found on human-made plastic environments.However, some diatoms, which are photosynthetic microalgae, did exhibit a preference for plastic type. Research has shown that hydrocarbon-degrading bacteria, or bacteria that may be capable of degrading plastics, can be associated with diatoms. This dynamic may ultimately prove convenient, as it could potentially promote the degradation of microplastics."I wish to further explore this diatom-hydrocarbon degrading bacteria relationship and assess if diatoms help to recruit hydrocarbon degrading bacteria to a plastics' surface," Dudek said.Dudek speculated that microplastics could also serve as a vehicle for toxic and disease-causing organisms. These contaminated microplastics could potentially be dragged from the coasts to the open oceans via currents, to be swallowed by fish or sink and affect the benthic communities on the ocean floor, but much research remains to be done regarding the role microplastics play in the transportation of pathogens."Only about 1% of marine plastic debris is recovered at the ocean's surface, meaning the other 99% likely either sinks or is consumed by marine organisms," Dudek said. "I am currently exploring the role microplastic biofilms have in a microplastic's degradation and sinking capacity in different marine environments."

Pollution

February 7, 2020

https://www.sciencedaily.com/releases/2020/02/200207074709.htm

New commuter concern: Cancerous chemical in car seats

The longer your commute, the more you're exposed to a chemical flame retardant that is a known carcinogen and was phased out of furniture use because it required a Proposition 65 warning label in California.

That is the conclusion of a new UC Riverside study published this month in the journal While much research on automobile pollution focuses on external air pollutants entering vehicle interiors, this study shows that chemicals emanating from inside your car could also be cause for concern.Though there are other Proposition 65-list chemicals that are typically used in the manufacture of automobiles, this flame retardant is a new addition to the list. Known as the Safe Drinking Water and Toxic Enforcement Act, Proposition 65 requires the state to maintain and update a list of chemicals known to cause cancer or reproductive harm.Some scientists assumed that humans stopped being exposed to the chemical, called TDCIPP or chlorinated tris, after it was placed on California's Proposition 65 list in 2013. However, it is still widely used in automobile seat foam. The study shows that not only is your car a source of TDCIPP exposure, but that less than a week of commuting results in elevated exposure to it.David Volz, associate professor of environmental toxicology at UCR, said the results were unexpected."I went into this rather skeptical because I didn't think we'd pick up a significant concentration in that short a time frame, let alone pick up an association with commute time," Volz said. "We did both, which was really surprising."Over the past decade, Volz has studied how various chemicals affect the trajectory of early development. Using zebrafish and human cells as models, the Volz laboratory has been studying the toxicity of a newer class of flame retardants called organophosphate esters since 2011.Little is known about the toxicity of these organophosphate esters -- TDCIPP is one of them -- but they've replaced older flame-retardant chemicals that lasted longer in the environment and took longer to metabolize.Using zebrafish as a model, Volz found TDCIPP prevents an embryo from developing normally. Other studies have reported a strong association between TDCIPP and infertility among women undergoing fertility treatments.Knowing its use is still widespread in cars, Volz wondered whether a person's exposure is elevated based on their commute. UC Riverside undergraduates made for excellent study subjects, as a majority of them have a daily commute.The research team included collaborators at Duke University and was funded by the National Institutes of Health as well as the USDA National Institute of Food and Agriculture.Participants included around 90 students, each of whom had commute times that varied from less than 15 minutes to more than two hours round trip. All of them were given silicone wristbands to wear continuously for five days.The molecular structure of silicone makes it ideal for capturing airborne contaminants. Since TDCIPP isn't chemically bound to the foam, Aalekyha Reddam, a graduate student in the Volz laboratory, said it gets forced out over time and ends up in dust that gets inhaled.Multiple organophosphate esters were tested, but TDCIPP was the only one that showed a strong positive association with commute time."Your exposure to TDCIPP is higher the longer you spend in your vehicle," Reddam said.While Volz and his team did not collect urine samples to verify that the chemical migrated into the bodies of the participants, they believe that's what happened."We presume it did because of how difficult it is to avoid the ingestion and inhalation of dust," Volz said. Additionally, other studies have examined the accumulation of TDCIPP in urine, but not as a function of how long a person sits in a car.Going forward, the research team would like to repeat the study with a larger group of people whose ages are more varied. They would also like to study ways to protect commuters from this and other toxic compounds.Until more specific reduction methods can be identified, the team encourages frequently dusting the inside of vehicles, and following U.S. Environmental Protection Agency guidelines for reducing exposure to contaminants.Until safer alternatives are identified, more research is needed to fully understand the effects of TDCIPP on commuters."If we picked up this relationship in five days, what does that mean for chronic, long-term exposure, for people who commute most weeks out of the year, year over year for decades?" Volz asked.

Pollution

February 6, 2020

https://www.sciencedaily.com/releases/2020/02/200206132337.htm

Scientists reveal whole new world of chemistry by stepping indoors

Colorado State University atmospheric chemist Delphine Farmer had spent her entire career probing the complexities of outdoor air -- how gases and particles in the atmosphere move, interact and change, and how human activities perturb the air we breathe. Then, she went inside.

That is, the Department of Chemistry associate professor turned her attention to the less-studied realm of indoor air. And she's come to discover that the chemistry inside can be vastly more complex than that of outdoor air systems.More than two years ago, Farmer and over 60 collaborators from 13 universities set in motion a first-of-its-kind experiment attempting to map the airborne chemistry of a typical home, subjected to typical home activities like cooking and cleaning. The effort was dubbed HOMEChem -- House Observations of Microbial and Environmental Chemistry -- and was led by Farmer and Marina Vance, a mechanical engineer at University of Colorado Boulder.Now, as the team sifts through the reams of data they collected, Farmer and her CSU research team have published their first major study from HOMEChem. The paper, appearing in On HOMEChem, her first foray into indoor chemistry, Farmer "became a convert when I heard the statistic that we spend 90 percent of our lives indoors.""It's puzzling, really, that all our health outcomes are tied to outdoor air," Farmer said. "It made me curious as a scientist when I realized just how little we know about chemistry indoors."Her team of graduate students and postdocs is now busy crunching more data and compiling potential follow-up studies.Backed by $1.1 million from the Sloan Foundation's Chemistry of Indoor Environments program, the HOMEChem team descended on the perfect location for their experiments: the Test House at University of Texas at Austin, a full-size, manufactured "home" that serves as a kind of blank slate for scientific experiments. The team occupied the house for most of June 2018, simulating activities in an average Western home. Their efforts are detailed in an overview paper in Environmental Science: Processes & Impacts.Their experimental run-of-show, which read very much like a family chore list, included things like cooking vegetable stir-fry, scrubbing surfaces with household products, and wet-mopping floors. One session was even dedicated to cooking a typical Thanksgiving meal while recording resulting emissions. All this, while operating hundreds of thousands of dollars' worth of sensitive equipment that could detect everything in the air from single-nanometer particles, to hundreds of different volatile organic compounds.Farmer's team from CSU included graduate students Jimmy Mattila, Matson Pothier and Erin Boedicker, and postdoctoral researchers Yong Zhou and Andy Abeleira. The team deployed 12 separate instruments for tracking three broad categories of compounds: organics, oxidants and particles. Postdoctoral researcher and data scientist Anna Hodshire recently joined Farmer's team and will be responsible for managing the large datasets the researchers gathered over the course of HOMEChem.For the bleach-cleaning study, Farmer's team recorded the airborne and aqueous chemistry from several consecutive days of mopping a floor with bleach, diluted to manufacturer's specifications. On some days, they also observed how that chemistry was affected when floors were mopped following a cooking session.According to the paper, the researchers observed sharp, albeit short-lived, spikes in hypochlorous acid, chlorine and nitryl chloride in the air, which are compounds more typically associated, at lower levels, with the outdoor air of coastal cities.Mattila, the paper's first author and graduate student who operated a chemical ionization mass spectrometer during HOMEChem, said the team was surprised to learn that multi-phase chemistry -- not just the gas phase -- controls the production and removal of inorganic compounds in the air during bleach cleaning. The bleach in the mop water, applied to the floor, would react with the molecules in the house's surfaces and walls to create new compounds. It turns out such surfaces -- and the layer of muck many homes accumulate from years of living -- can act as reservoirs for a wide variety of acidic and basic molecules that can then interact with substances like bleach."You would intuitively think that since we're making these fumes in the air, and there's other stuff in the air, they're probably just reacting," Mattila said. "It turns out that indoor multiphase chemistry, in the bleach solution and on various indoor surfaces, is what's actually driving the observations."The group collaborated with scientists at UC Irvine to develop a model for understanding how the aqueous and surface molecules lead to secondary chemistry.When they mopped after cooking, they also observed interactions of nitrogen and ammonia emissions from the food with the cleaning products. They saw low levels of chloramines, considered harmful to human health, which are made when chlorine mixes with ammonia. Humans also breathe out trace amounts of ammonia."If you look on any bottle of bleach, you'll see a serious warning not to mix chlorine and ammonia, because it will make a dangerous set of compounds called chloramines," Farmer said. "What we found is there was enough ambient ammonia to still make some of these compounds, even without mixing them. Not to the point where it was dangerous, but it was interesting to see that chemistry happening."An obvious takeaway from the researchers: When cleaning with bleach, open a window or use a fan to increase ventilation. And always appropriately dilute the solution; cleaning with straight bleach could create dangerous breathable compounds, depending on what else is in the air or on the walls.The entire HOMEChem experiment was unprecedented in its scope. The study is an attempt at establishing a baseline understanding of what a person at home, doing typical home activities, can expect to be breathing. Among the key takeaways from the experiments as a whole was that combining different indoor activities leads to very different chemistry in the house."For example, we see that cleaning with bleach after you clean indoors with a terpene solution, like Pine Sol, can actually lead to some chemistry you wouldn't normally see with bleach alone," Mattila said. "That was kind of unexpected, and could be potentially harmful, because it could lead to the production of secondary organic aerosols."HOMEChem was a measurement experiment and did not involve epidemiologists. The researchers believe their data will serve as a useful starting point for inquiries into human health outcomes tied to indoor air environments.

Pollution

February 5, 2020

https://www.sciencedaily.com/releases/2020/02/200205103227.htm

Nanoparticles produced from burning coal result in damage to mice lungs

Virginia Tech scientists have discovered that incredibly small particles of an unusual and highly toxic titanium oxide found in coal smog and ash can cause lung damage in mice after a single exposure, with long-term damage occurring in just six weeks.

The tests were headed by Irving Coy Allen, a professor with the Virginia-Maryland College of Veterinary Medicine, with collaborators from across Virginia Tech and researchers at the University of Colorado, the University of North Carolina at Chapel Hill, East Carolina University, and East China Normal University in Shanghai. The findings were recently published in the scientific journal They follow 2017 findings by Virginia Tech geoscientist Michael Hochella that burning coal -- when smoke is not captured by high-end filters currently found in U.S. power plants -- emits tiny particulates known as titanium suboxide nanoparticles into the atmosphere. Such nanoparticles were found by Hochella's team of scientists in ash collected from the city streets, sidewalks, and in ponds and bays near U.S. and Chinese cities.Using mouse models in a lab setting, these tiniest of nanoparticles -- as small as 100 millionths of a meter -- entered the lungs after being inhaled. Once inside the lungs, the nanoparticles encountered macrophages, the lungs' defensive cells that trap and remove foreign materials. Typically, these cells protect the lungs from pathogens, such as bacteria and viruses. But against these nanoparticles, the macrophages falter."They can't break the titanium nanoparticles down, so the cells begin to die, and this process recruits more macrophages. These processes begin a feedback loop with each round of dying cells concentrating around the nanoparticles," said Allen, a member of the Department of Biomedical Sciences and Pathobiology. "The dying, nanoparticle-containing cells then begin making deposits in the lungs and these deposits cause problems. We begin seeing negative impacts on lung function, and basically the lungs fail to continue to work correctly."In what Allen calls a "striking find," his team discovered negative effects after only one exposure to the toxic nanoparticles. Long-term damage from the deposits can appear in as little as six weeks, raising concerns for highly polluted cities. "We realized if someone is living near a power plant, or near one of these coal burning sources, they wouldn't be exposed to a single dose, they'd be exposed to this daily," he said. "We also did not see lung clearance after a week, so when these things are in your lungs they are staying there, and they are staying there for an extended period of time."More so, damaged lungs can lead to higher susceptibility to virus or bacterial infection, and could worsen symptoms associated with asthma or chronic obstructive pulmonary disease (COPD).However, the exact effects of these toxic nanoparticles on humans, other animals, vegetation, and water systems are not known and demand further study by international researchers, Allen said."Mouse and human lungs are functionally similar, but anatomically different in a variety of subtle ways," Allen added. "While the studies done in this paper are commonly utilized to model airway disorders in people, more direct clinical data are necessary to fully understand the human impact of exposure to these nanoparticles."The titanium suboxide nanoparticles -- called Magnéli phases by researchers -- were once thought rare, found on Earth in some meteorites, from a small area of certain rocks in western Greenland, and occasionally in moon rocks. However, Hochella, working with other researchers in 2017, found that these nanoparticles are in fact widespread globally from the burning of coal.According to the earlier study, published in Early biotoxicity studies by Hochella's group with zebra fish embryos showed signs of negative biological impact from the nanoparticles, suggesting potential harm to humans. Now, with this study, the odds of toxicity to humans are much greater. "The problem with these nanoparticles is that there is no easy or practical way to prevent their formation during coal burning," said Hochella, University Distinguished Professor Emeritus of Geosciences with the Virginia Tech College of Science, upon the earlier study's release two years ago.Hochella and his team came across the titanium suboxide nanoparticles quite by accident while studying the downstream movement of a 2014 coal ash spill in the Dan River of North Carolina. The group later produced the same titanium suboxide nanoparticles when burning coal in lab simulations. This potential health hazard builds on established findings from the World Health Organization: More than 3.3 million premature deaths occurring worldwide per year due to polluted air, and in China alone, 1.6 million premature deaths are estimated annually due to cardiovascular and respiratory injury from air pollution.This raises multiple questions: Are the nanoparticles absorbed through the body by other means, such as contact with eyes or skin? Can they find their way into vegetation -- including food -- though soil? If so, what are the implications on the gastrointestinal tract? Are they present in drinking water? If a mouse experiences long-term damage at six weeks, what does that pose for humans who breathe the air?Allen urges that testing move to human-focused studies."We've identified a unique pollutant in the environment, and we've shown there's a potential health concern for humans, so that gives us a biomarker that we can monitor more closely," he said. "We should begin looking at these particulates more closely as we become more aware of the hazards these nanoparticles pose. These are questions that need to be asked."That path, while obvious, may not be so simple, ethically or politically. Scientists can't expose human test subjects to coal smog or ash and the toxic nanoparticles. Therefore, a likely scenario: scientists could study these particles in human lung tissue from lung biopsies and clinical specimens. However, many clinicians have been reluctant to take part in this effort in many of the countries at the most risk. Allen said one reason may be the sensitivity that these countries hold toward air-quality issues.

Pollution

February 4, 2020

https://www.sciencedaily.com/releases/2020/02/200204094744.htm

Lights out? Fireflies face extinction threats of habitat loss, light pollution, pesticides

Habitat loss, pesticide use and, surprisingly, artificial light are the three most serious threats endangering fireflies across the globe, raising the spectre of extinction for certain species and related impacts on biodiversity and ecotourism, according to a Tufts University-led team of biologists associated with the International Union for the Conservation of Nature.

Fireflies belong to a widespread and economically important insect group, with more than 2,000 different species spread out across the globe. To better understand what threats are faced by fireflies, the team led by Sara Lewis, professor of biology at Tufts University, surveyed firefly experts around the world to size up the most prominent threats to survivial for their local species.Their perspective piece, published today in According to survey respondents, habitat loss is the most most critical threat to firefly survival in most geoographic regions, followed by light pollution and pesticide use."Lots of wildlife species are declining because their habitat is shrinking," said Lewis "so it wasn't a huge surprise that habitat loss was considered the biggest threat. Some fireflies get hit especially hard when their habitat disappears because they need special conditions to complete their life cycle. For instance, one Malaysian firefly [One surprising result that emerged from the survey was that, globally, light pollution was regarded as the second most serious threat to fireflies.Artificial light at night has grown exponentially during the last century. "In addition to disrupting natural biorhythms -- including our own -- light pollution really messes up firefly mating rituals," explained Avalon Owens, Ph.D. candidate in biology at Tufts and a co-author on the study. Many fireflies rely on bioluminescence to find and attract their mates, and previous work has shown that too much artificial light can interfere with these courtship exchanges. Switching to energy efficient, overly bright LEDs is not helping. "Brighter isn't necessarily better," says Owens.Firefly experts viewed the widespread agricultural use of pesticides as another key threat to firefly survival.Most insecticide exposure occurs during larval stages, because juvenile fireflies spend up to two years living below ground or under water. Insecticides such as organophosphates and neonicotinoids are designed to kill pests, yet they also have off-target effects on beneficial insects. While more research is needed, the evidence shows that many commonly used insecticides are harmful to fireflies.A few studies have quantified firefly population declines, such as those seen in the tourist-attracting synchronous fireflies of Malaysia, and the glowworm Lampyris noctiluca in England. And numerous anecdotal reports suggest that many other firefly species across a wide range of habitats have also suffered recent declines. "However," Lewis points out, "we really need better long-term data about firefly population trends -- this is a place where citizen science efforts like Massachusetts Audubon's Firefly Watch project can really help."The researchers also highlight risk factors that allow them to predict which species will be most vulnerable when faced with threats like habitat loss or light pollution. For instance, females of the Appalachian blue ghost firefly [Phausis reticulata] are flightless. "So when their habitat disappears, they can't just pick up and move somewhere else," explains co-author J. Michael Reed, professor of biology at Tufts. Yet the researchers remain optimistic about fireflies' future. "Here in the U.S., we're fortunate to have some robust species like the Big Dipper fireflies [Photinus pyralis]," notes Lewis. "Those guys can survive pretty much anywhere- and they're beautiful, too."By illuminating these threats and evaluating the conservation status of firefly species around the world, researchers aim to preserve the magical lights of fireflies for future generations to enjoy. "Our goal is to make this knowledge available for land managers, policy makers, and firefly fans everywhere," says co-author Sonny Wong of the Malaysian Nature Society. "We want to keep fireflies lighting up our nights for a long, long time."

Pollution

February 4, 2020

https://www.sciencedaily.com/releases/2020/02/200204094717.htm

Green infrastructure provides benefits that residents are willing to work for, study shows

Urban areas face increasing problems with stormwater management. Impervious surfaces on roads and buildings cause flooding, which impacts the water quality of streams, rivers and lakes. Green infrastructure, including features such as rain barrels, green roofs, rain gardens, and on-site water treatment, can provide affordable and environmentally sound ways to manage precipitation.

However, green infrastructure is challenging to maintain, because it is decentralized across a city and requires constant maintenance and upkeep. One way city management can address those challenges is to rely on volunteers to help maintain such features.A new study from the University of Illinois and Reed College aims to estimate the value people place on improved water quality and storm management, and how much time and money they are willing to contribute to enjoy those benefits.The researchers presented respondents in Chicago and Portland, Oregon, with a series of hypothetical scenarios that described ways to reduce flooding, improve water quality, and strengthen aquatic habitats in local rivers and streams."Our research indicates that these environmental goods produced by green infrastructure have significant monetary value, and that people might be willing to volunteer a significant amount of time to help provide those goods," says Amy Ando, professor of agricultural and consumer economics at U of I, and one of the study's authors.The paper, published in the Ando and co-authors Catalina Londoño Cadavid, Noehwah Netusil, and Bryan Parthum found that people are willing to make considerable contributions both in terms of time and money. For example, improved water quality is estimated to be worth about $280 a year per household. If flooding is cut in half, that benefit is estimated to be worth $300 a year. These amounts indicate how much people would be willing to pay in fees or taxes to obtain those specific benefits.The study also showed that people may be willing to spend a considerable amount of time working to support these environmental features, especially if it directly benefits their local community."We were surprised at the large stated willingness to volunteer that people indicated," Ando says. "For example, the average respondent was willing to spend 50 hours a year on an ambitious project to restore aquatic habitat to excellent condition and water quality to be swimmable."Comparing the results from Chicago and Portland, the researchers found little difference in monetary values; however, Portland residents were much more willing to volunteer their time for environmental benefits. Ando notes that while the research does not address why that may be the case, Portland has extensive volunteer programs in place, so there may already be a strong culture of volunteering among residents.Ando says the surveys were designed to reduce hypothetical bias, or the likelihood that people indicate higher values than they would actually contribute. However, those techniques are developed for estimations of money spent, not for volunteer hours, so it remains uncertain if respondents would actually work as much as they indicate."People are used to the idea that if there is a city fee you have to pay it. But volunteering is volunteering. You can't force people to work," she notes.Still, even if respondents exaggerate or overestimate their willingness to work, the results indicate that green infrastructure is considered important enough to spur considerable interest in contributing both time and money."The results of our paper seem encouraging to cities, indicating that they might well be able to put together a network of people that could help with decentralized management of green infrastructure," Ando says. "It encourages them to think about systems of harnessing energy of community volunteers to help maintain green infrastructure that's put in place to provide some of those environmental benefits."The research also indicated that willingness to volunteer may be driven in part by the direct utility people get from volunteering in their neighborhoods. Ando says this connection is important and should be a topic for future research.Another takeaway from the study is the value of water quality for residents."Often, when cities are talking about green infrastructure, they're very focused on flood reduction. That was not actually the biggest value that we found. We found evidence that people place very high values on improving habitat for aquatic creatures in urban rivers and streams, and in reducing water pollution so the rivers and streams are more usable by people who live near them," Ando states."One of the implications of our research is that urban water managers should be focused on providing those benefits and not just worry about flood reduction," she concludes.

Pollution

February 3, 2020

https://www.sciencedaily.com/releases/2020/02/200203141455.htm

Aerosols have an outsized impact on extreme weather

Scientists at Caltech and JPL have tied a shift in winter weather patterns in Europe and northern Eurasia to a reduction in air pollution.

Over the past 50 years, the occurrence of extremely cold days has decreased throughout Europe and northern Eurasia, which includes Russia. Combining long-term observations with a state-of-the-art climate model revealed what researchers describe as an "unambiguous signature" of the reduction in the release of human-made aerosols over that time. This has caused changes in the wintertime Northern Hemisphere polar jet stream (a swiftly moving channel of air flowing from west to east) and surface-temperature variability during that time.The work suggests that aerosols, which are solid particles polluting the atmosphere from activities like burning coal, can have a stronger impact on extreme winter weather than greenhouse gases at regional scale, although the relationship between aerosols and extreme weather is complicated to untangle."This discovery underscores the importance of understanding the effects of anthropogenic aerosols for accurate climate projection of extreme weather events, which is crucial to formulating climate mitigation and adaption strategies," says Yuan Wang, staff scientist at Caltech and at JPL, which Caltech manages for NASA, and the lead author of a study about the research that was published in Wang and his colleagues found that tighter air pollution regulations led to a reduction in atmospheric aerosols, and, as there were fewer particles in the atmosphere to reflect sunlight, this resulted in a local warming effect. Warmer temperatures in Europe led to a stronger temperature gradient between Europe and the North Pole, which in turn helped lock the jet stream into a stable, relatively straight position.When the jet stream meanders, dipping south, it can carry cold arctic air to more southern latitudes. Some climate models have predicted that the steady increase in the arctic temperature, caused by greenhouse gas-driven global warming, could weaken the jet stream and cause it to meander, but Wang's team has found a more complicated underlying mechanism."This tells us that for winter extremes, aerosols have a greater impact than greenhouse gases," says Jonathan Jiang of JPL, co-corresponding author of the Because China is expected to enact air pollution regulations that will lead to aerosol reductions over the next two to three decades, the model predicts that a similar effect could also be seen over eastern Asia.

Pollution

February 3, 2020

https://www.sciencedaily.com/releases/2020/02/200203141448.htm

Oil spill clean-up: Better method

Oil poses a considerable danger to aquatic life. Researchers at the Universities of Bonn and Aachen and the Heimbach-GmbH have developed a new technology for the removal of such contaminations: Textiles with special surface properties passively skim off the oil and move it into a floating container. The scientists used surfaces from the plant kingdom as a model. The study has now been published in the journal

The video clip is as short as it is impressive: The 18-second sequence shows a pipette from which dark-colored crude oil drips into a glass of water. Then a researcher holds a green leaf against the spot. Within a matter of seconds the leaf sucks the oil from the surface of the water, leaving not even a trace behind.The star of the movie, the small green leaf, comes from the floating fern Salvinia. The special abilities of its leaves make it highly interesting for scientists, because they are extremely hydrophobic: When submerged, they wrap themselves in an air jacket and remain completely dry. Researchers call this behavior "superhydrophobic," which can be translated as "extremely water repellent."However, the Salvinia surface loves oil which is, in a way, a flip side of superhydrophobia. "This allows the leaves to transport an oil film on their surface," explains Prof. Dr. Wilhelm Barthlott, emeritus of the University of Bonn and former director of its botanic gardens. "And we have also been able to transfer this property to technically producible surfaces, such as textiles."Such superhydrophobic substances can then for instance be used to remove oil films from water surfaces efficiently and without the use of chemicals. However, unlike other materials that have been used for this purpose so far, they do not absorb the oil. "Instead, it travels along the surface of the fabric, moved forward solely by its adhesive forces," explains Barthlott. "For example, in the laboratory we hung such fabric tapes over the edge of a container floating on the water. Within a short time they had almost completely removed the oil from the water surface and transported it into the container." Gravity provides the power; the bottom of the container must therefore be below the water surface with the oil film. "The oil is then completely skimmed off -- as if using an automatic skimming spoon for meat stock."This also makes super-hydrophobic textiles interesting for environmental technology. After all, they promise a new approach to solving the acute environmental problem of increasing oil spills on water bodies. Oil films floating on water cause a number of problems. They prevent gas exchange through the surface and are also dangerous on contact for many plants and animals. As oil films also spread quickly over large surfaces, they can endanger entire ecosystems.The new process does not require the use of chemicals. Conventional binding agents simply absorb the oil and can then usually only be burned later. The superhydrophobia method is different: "The oil skimmed into the floating container is so clean that it can be reused," explains Prof. Barthlott.The procedure is not intended for large-scale oil disasters such as those that occur after a tanker accident. But particularly small contaminations, such as engine oil from cars or ships, heating oil or leaks, are a pressing problem. "Even minor quantities become a danger to the ecosystem, especially in stagnant or slow-flowing waters," emphasizes the biologist. This is where he sees the major application potential of the new method, for which a patent has been filed by the University of Bonn.Generally speaking, many surfaces exhibit superhydrophobic behavior, albeit to varying degrees. The basic prerequisite is first of all that the material itself is water-repellent, for example due to a wax coating. But that alone is not enough: "Superhydrophobia is always based on certain structures on the surface, such as small hairs or warts -- often on a nanotechnological scale," explains the botanist from the University of Bonn. It is also thanks to him that science now knows much more about these relationships than it did a few decades ago.The research work is funded by the Deutsche Bundesstiftung Umwelt DBU. "This now helps us to develop oil-absorbing materials with particularly good transport properties, in cooperation with RWTH Aachen University," says Barthlott.

Pollution

February 3, 2020

https://www.sciencedaily.com/releases/2020/02/200203104502.htm

Agricultural area residents in danger of inhaling toxic aerosols

Excess selenium from fertilizers and other natural sources can create air pollution that could lead to lung cancer, asthma, and Type 2 diabetes, according to new UC Riverside research.

The research team conducted previous UCR studies in the Salton Sea area, which contains selenium rich wetlands and soils toxic to birds and fish. These' studies also revealed that the area's concentration of aerosols, which are solid or liquid particles suspended in air, have increased in recent years.However, the full chemical makeup of the aerosols, or whether they would have any effects on humans, remained unknown. This motivated the team to create similar aerosol particles in the laboratory and study them.The team's new paper, published in the journal Though the Salton Sea-area aerosols are likely to be unhealthy, UCR Associate Professor of Atmospheric Science Roya Bahreini said people in nearby San Bernardino, Los Angeles, and Riverside counties are likely safe."Typically, the air masses from the Salton Sea area don't reach these cities," she said.According to Bahreini, dangerous aerosols can occur anywhere there's excessive selenium in the soil, making agricultural workers and those living near contaminated soils more vulnerable to illnesses.Along with naturally occurring selenium in the environment, the excess from humanmade sources gets digested by soil microbes and processed by plants. Once excreted, the selenium-containing vapors, which include the compound dimethyl selenide, mix with other airborne chemicals and eventually become the toxic selenium-containing aerosol, which stays in the air for roughly a week.Selenium in small amounts is important for regulating the immune system. Deficiency can cause thyroid issues, slowed growth, and impaired bone metabolism.As with most substances, too much can be poisonous. An excess of selenium can lead to swollen lungs, garlic breath, gastrointestinal disorders, neurological damage, and hair loss.Scientists once believed dimethyl selenide was less toxic than other forms of selenium. In fact, Bahreini said scientists once proposed planting specific grasses in wetlands and soils with excessive amounts of selenium to allow digestion and evaporation of selenium-containing vapors as a way to remediate these sites.However, earlier mouse studies showed the aerosols can cause lung injury and inflammation in mice. According to Ying-Hsuan Lin, an assistant professor of environmental toxicology at UCR, this newest study also shows how dimethyl selenide can form aerosols and affect humans.Lin's team tested the aerosols on human lung cells in her laboratory and found they damage the lung's protective barrier."If people are exposed to this long enough, or in high enough concentration, they have a greater risk of lung cancer," Lin said. "There is also evidence that the aerosols can cause allergic inflammation of the lungs, and disturb glucose metabolism, which are linked to asthma and Type 2 diabetes."The team is planning further studies to understand asthma rates that may be linked to the allergic inflammation she observed.In addition, Lin said it is important to identify other sources of selenium-containing aerosols, as this study only identifies one source."We need to control this to improve public health," she said.

Pollution

January 31, 2020

https://www.sciencedaily.com/releases/2020/01/200131125602.htm

New research looks at type 1 diabetes and changes in the environment

Studies have shown a rapid increase in new cases of type 1 diabetes worldwide. However, scientists and researchers have struggled to identify a direct cause. Many have questioned if changes in the environment or lifestyle have impacted the disease. In a newly released review paper published in The

"The incidence of type 1 diabetes has increased 3 percent per year over the past three decades. This increase is too rapid to be due to genetic factors, suggesting that environmental factors may play a role," said Jill Norris, MPH, PhD, professor and chair of epidemiology at the Colorado School of Public Health and lead author of the paper.Identifying environmental factors associated with type 1 diabetes that influence its incidence can inform future preventive trials and searches for other environmental risk factors. In this paper, researchers reviewed the literature on environmental factors like air pollution, diet, childhood obesity, the duration of breastfeeding, the introduction of cow's milk, infections, and many others that showcase an impact on type 1 diabetes.The researchers then looked at prevalence of an exposure over time while varying its annual increase under simulated scenarios. Using the simulated data, the research showed that if a single factor were to explain the changes in the incidence of type 1 diabetes over the past few decades, it would have to be very strongly associated with the risk of type 1 diabetes.The simulated scenarios showed that an environmental factor that increased at a constant rate from nearly absent in the population to nearly ubiquitous would have to confer a relative risk of 5 to explain an approximately 3 percent annual increase in the incidence of type 1 diabetes. However, most of the environmental factors reviewed had a relative risk of less than 2."While several factors have been associated with type 1 diabetes, none of the associations are of a magnitude that can explain the rapid increase in incidence alone," Norris said. "Moreover, evidence of the changing prevalence of these same exposures over time is not convincing nor consistent."The paper explains that more research is required, and it is possible that multiple factors simultaneously may account for the increase in type 1 diabetes cases. Other factors are that the magnitude of observed associations may have been underestimated due to exposure measurement error or mismodeling of complex exposure-time-response relationships.The study concludes that the identification of environmental factors influencing type 1 diabetes risk and increased understanding of the etiology at the individual level, regardless of the ability to explain the changing incidence at the population level, is important because of the implications for prevention.

Pollution

January 29, 2020

https://www.sciencedaily.com/releases/2020/01/200129212259.htm

City in a test tube: Researchers simulate urban pollution to show how it damages the heart

A unique study mimicking city centre pollution levels shows how just two hours of bad air adversely affects the heart and blood vessels for a whole day. The research is published today in the

"After two hours of breathing polluted air, study participants showed the first steps of cardiovascular disease and the effects lasted for 24 hours," said study author Professor Dimitris Tousoulis of the National and Kapodistrian University of Athens, Greece. "To avoid permanent harm, we had to keep pollution levels in the study under safe limits, implying that even 'safe' levels may be devastating to health when frequently repeated -- as occurs in city dwellers."Population studies have documented the adverse connection between air pollutants (of which 50% come from diesel exhaust fumes) and cardiovascular health. However, the specific effects of diesel emissions on the body, which lead to disease, are not fully understood.This study clarifies how breathing urban levels of diesel exhaust fumes for a relatively short time has prolonged and multiple effects on the cardiovascular system.A total of 40 healthy volunteers were randomised to diesel exhaust fumes or filtered air for two hours in a specially designed hermetically sealed (airtight) laboratory. After four weeks, participants then swapped over so that everyone had a pollution session and a clean-air session.For the pollution session, diesel emissions were produced by a diesel engine. Throughout session, levels of carbon monoxide and other pollutants resembled those in crowded city centres.To assess the impact of diesel exhaust fumes on the cardiovascular system, the researchers measured blood vessel function and suppleness, heart rate, blood clotting, and inflammation -- all of which indicate the health of the heart and blood vessels. To ensure that any changes in these parameters were due to diesel emissions, participants avoided alcohol, caffeine, smoking and changes in diet during the study period.Compared to filtered air, polluted air had a prolonged (at least 24 hours) detrimental effect on all of the measurements."We assessed key steps in the process of blood vessels becoming blocked and eventually causing a heart attack or stroke," explained Professor Tousoulis. "Short-term exposure to diesel exhaust fumes simultaneously impacts these stages, with long-lasting effects."He concluded: "Our study provides insights into the mechanisms by which diesel exhaust fumes heighten cardiovascular risk. The damaging effects shown in this research are likely to multiply with repeated -- and for some people lifelong -- exposure to high levels of diesel exhaust fumes in cities, heavy traffic, road tunnels, enclosed garages, and on large highways. More efficient public health measures are needed to improve air quality in cities and prevent needless heart attacks and strokes."

Pollution

January 29, 2020

https://www.sciencedaily.com/releases/2020/01/200129125602.htm

New way of recycling plant-based plastics instead of letting them rot in landfill

Scientists have developed new way to break down plant-based plastics into their original building blocks, potentially allowing products to be recycled repeatedly without a loss in the quality of the plastic.

Around 45% of plastic waste is recycled annually in the UK and is on the increase. However one of the problems with current plastic recycling methods is that you end up with a lower quality plastic with worse properties than the original. This means that plastic drinks bottles cannot simply be recycled into new drinks bottles continuously, but instead are used for other lower grade products such as water pipes, park benches and traffic cones.Now scientists from the Universities of Bath and Birmingham have developed a new way of chemical recycling -- converting plastics back into their constituent chemical molecules -- so that they can be used to make new plastics of the same quality as the original.The team's method, published in Professor Matthew Jones, from the Centre for Sustainable & Circular Technologies at the University of Bath, said: "Most plastic is currently recycled using mechanical methods, where they are chipped into granules and melted down before being moulded into something new."The problem is, melting plastic changes its properties, and reduces the quality, which limits the range of products in which it can be used."Our method of chemical recycling overcomes this problem by breaking down plastic polymers into their chemical building blocks, so they can be used all over again to make virgin plastic without losing any properties."The researchers recycled plant-based PLA, which is made from starch or crop waste instead of petrochemicals, and is used in "biodegradable" food packaging and disposable cutlery and cups. PLA isn't currently recycled because it's not used widely yet, however with growing awareness of plastic pollution, the demand from consumers for recyclable packaging is growing.The team has also started trialling a similar process for recycling PET, which is used for drinks bottles.First author of the paper, Dr Paul McKeown from the University of Bath, said: "PLA is being increasingly used as a sustainable alternative for single-use plastics. Whilst it's biodegradable under industrial conditions, it doesn't biodegrade with home composting, and isn't currently recycled, so at the moment it commonly ends up contributing to the tonnes of plastic waste in landfill and oceans."There is no single solution to the problem of plastic waste -- the approach has to be a combination of reducing, reusing and recycling. Our method of chemical recycling could allow carbon to be recycled indefinitely -- creating a circular economy rather than digging more up from the ground in the form of fossil fuels, or releasing it into the atmosphere as a greenhouse gas."So far, the technology has only been demonstrated on a small scale, however collaborators at the University of Birmingham are now working to scale up the system to produce larger quantities of starting chemicals.

Pollution

January 29, 2020

https://www.sciencedaily.com/releases/2020/01/200129104712.htm

Airborne microbes link Great Barrier Reef and Australian continent

A team of researchers led by Yale-NUS College Professor of Science (Environmental Studies) Stephen Pointing has discovered a link between two different ecosystems, continental Australia and the Great Barrier Reef, due to airborne microbes that travel from the former to the latter. The finding showed that the health of these two ecosystems are more interconnected than previously believed, hence holistic conservation efforts need to span different ecosystems.

Microbes are fundamental to the health of ecosystems, playing roles such as providing energy, oxygen and carbon to other organisms and recycling nutrients from other organisms' waste products. Prof Pointing's team recently published two papers in established scientific journals The team's success has grown from development of a new apparatus and methodology to accurately study microbes in air -- something that has never been previously done due to the low abundance of airborne microbes and how quickly they degrade once captured for sampling. The team's first paper, published in the June 2019 issue of the peer-reviewed journal Their second paper, published in While there has long been speculation that airborne microbes are absorbed into the Reef, this was the first study that confirmed the existence of such a link. Genetic testing highlighted that the most abundant shared species in the air and coral played important functional roles in both coral and soil ecosystems, suggesting that the atmosphere acts to connect these ecosystems by transporting microbes essential to the health of each between them.Prof Pointing, who is also Director of the Division of Science at Yale-NUS, said, "In order to make effective policy decisions to protect our natural environment, it is vital to have reliable data on the level of connectivity between different ecosystems. The role that the air plays in ecosystem connectivity has not been appreciated until now. Our research provides empirical evidence that distant ecosystems on land and at sea are connected by the multitude of microorganisms such as bacteria and fungi that are transported in air currents between these ecosystems. Because microorganisms are so important to ecosystem health, any change to their transport patterns can have potentially catastrophic environmental impacts."The team's third paper, specially commissioned by

Pollution

January 29, 2020

https://www.sciencedaily.com/releases/2020/01/200129091447.htm

Microplastics from ocean fishing can 'hide' in deep sediments

Microplastic pollution in the world's oceans is a growing problem, and most studies of the issue have focused on land-based sources, such as discarded plastic bags or water bottles. Now, researchers reporting in ACS'

Fishing gear, such as nets, ropes and pots, is a potential sea-based source of microplastics. The tiny particles could be worn away from fishing gear during use, or they might arise when the gear is lost or discarded in the ocean. Yinghui Wang and colleagues wanted to measure microplastics in surface sediment samples from different sites in Beibu Gulf, a traditional fishing ground of China and the China-Indo peninsula that lacks substantial industrialization and urbanization. They also wanted to look for this type of contamination in deep sediments, up to 2 feet below the surface, which have not been well studied with respect to microplastic pollution.The researchers collected 52 sediment samples from Beibu Gulf and adjacent rivers in July 2017. Microplastics were separated from sediment samples and counted under a microscope. Most of the particles were made of polypropylene (PP) or polyethylene (PE), which are materials widely used in fishing nets and rope. The team found a strong correlation between the intensity of fishing activities, such as capture fishing or mariculture, and the abundance of PP and PE fibers. Unexpectedly, microplastics were detected even one foot below the surface, which corresponds to about the year 1913 (before the observed plastics were invented). The particles could have been transported to deep sediment layers by marine worms. Because most previous studies have considered only microplastics in surface sediment, this type of pollution in ocean sediments worldwide could be greatly underestimated, the researchers say.

Pollution

January 29, 2020

https://www.sciencedaily.com/releases/2020/01/200129091444.htm

Finer particulate matter (PM1) could increase cardiovascular disease risk

In addition to harmful gases such as carbon monoxide, air pollution contains tiny particles that have been linked to health problems, including cardiovascular disease and asthma. Most studies have analyzed the potential health effects of larger-sized particulate matter (PM), such as particles less than 2.5 μm in diameter (PM

To better understand air pollution, a nationwide PM

Pollution

January 29, 2020

https://www.sciencedaily.com/releases/2020/01/200129091359.htm

Potential global spread of new coronavirus

Experts in population mapping at the University of Southampton have identified cities and provinces within mainland China, and cities and countries worldwide, which are at high-risk from the spread of the 2019 Novel Coronavirus (2019-nCoV).

A report by the University's WorldPop team has found Bangkok (Thailand) is currently the city most at risk from a global spread of the virus -- based on the number of air travellers predicted to arrive there from the worst affected cities in mainland China. Hong Kong (China) is second on the list, followed by Taipei (Taiwan, the Republic of China). Sydney (12), New York (16) and London (19) are among 30 other major international cities ranked in the research.The most 'at-risk' countries or regions worldwide are Thailand (1), Japan (2) and Hong Kong (3). USA is placed 6th on the list, Australia 10th and the UK 17th.Within mainland China, the cities of Beijing, Guangzhou, Shanghai and Chongqing are all identified as high-risk by the researchers, along with the Chinese provinces of Guangdong, Zhejiang, Sichuan and Henan.Andrew Tatem, Director of WorldPop and professor within Geography and Environmental Science at the University of Southampton, says: "It's vital that we understand patterns of population movement, both within China and globally, in order to assess how this new virus might spread -- domestically and internationally. By mapping these trends and identifying high-risk areas, we can help inform public health interventions, such as screenings and healthcare preparedness."The team at WorldPop used anonymised mobile phone and IP address data (2013-15)1, along with international air travel data (2018)2 to understand typical patterns of movement of people within China, and worldwide, during the annual 40-day Lunar New Year celebrations (including the seven day public holiday from 24 to 30 January).From this, they identified 18 Chinese cities (including Wuhan) at high-risk from the new coronavirus and established the volume of air passengers likely to be travelling from these cities to global destinations (over a three month period). The team was then able to rank the top 30 most at-risk countries and cities around the world.The researchers acknowledge that their analysis is based on 'non-outbreak' travel patterns, but highlight that a high proportion of people travelled with symptoms at an early stage of the outbreak, before restrictions were put in place. In fact, travel cordons are likely to have only coincided with the latter stages of peak population numbers leaving Wuhan for the holiday period. According to Wuhan authorities it is likely more than five million people had already left the city.Lead report author Dr Shengjie Lai of the University of Southampton comments: "The spread of the new coronavirus is a fast moving situation and we are closely monitoring the epidemic in order to provide further up-to-date analysis on the likely spread, including the effectiveness of the transport lockdown in Chinese cities and transmission by people returning from the Lunar New Year holiday, which has been extended to 2 February."WorldPop at the University of Southampton conducted this research in collaboration with the University of Toronto, St Michael's Hospital Toronto, disease surveillance organisation Bluedot in Toronto and the China Centre for Disease Control and Prevention.Full data can be found in the report on the WorldPop website at: 1) De-identified and aggregated domestic population movement data (from 2013 to 2015), derived from Baidu Location-Based Services (LBS).2) International air travel data (2018), obtained from the International Air Transport Association (IATA)

Pollution

January 28, 2020

https://www.sciencedaily.com/releases/2020/01/200128114625.htm

Instant hydrogen production for powering fuel cells

Since the Industrial Revolution, the environmental impacts of energy have posed a concern. Recently, this has driven researchers to search for viable options for clean and renewable energy sources.

Due to its affordability and environmental friendliness, hydrogen is a feasible alternative to fossil fuels for energy applications. However, due to its low density, hydrogen is difficult to transport efficiently, and many on-board hydrogen generation methods are slow and energy intensive.Researchers from the Chinese Academy of Sciences, Beijing and Tsinghua University, Beijing investigate real-time, on-demand hydrogen generation for use in fuel cells, which are a quiet and clean form of energy. They describe their results in the The researchers used an alloy -- a combination of metals -- of gallium, indium, tin and bismuth to generate hydrogen. When the alloy meets an aluminum plate immersed in water, hydrogen is produced. This hydrogen is connected to a proton exchange membrane fuel cell, a type of fuel cell where chemical energy is converted into electrical energy."Compared with traditional power generation methods, PEMFC inherits a higher conversion efficiency," said author Jing Liu, a professor at the Chinese Academy of Sciences and Tsinghua University. "It could start rapidly and run quietly. Moreover, a key benefit to this process is that the only product it generates is water, making it environmentally friendly."They found the addition of bismuth to the alloy has a large effect on hydrogen generation. Compared to an alloy of gallium, indium and tin, the alloy including bismuth leads to a more stable and durable hydrogen generation reaction. However, it is important to be able to recycle the alloy in order to further reduce cost and environmental impact."There are various problems in existing methods for post-reaction mixture separation," Liu said. "An acid or alkaline solution can dissolve aluminum hydroxide but also causes corrosion and pollution problems."Other byproduct removal methods are difficult and inefficient, and the problem of heat dissipation in the hydrogen reaction process also needs to be optimized. Once these difficulties are resolved, this technology can be used for applications from transportation to portable devices."The merit of this method is that it could realize real-time and on-demand hydrogen production," said Liu. "It may offer a possibility for a green and sustainable energy era."

Pollution

January 28, 2020

https://www.sciencedaily.com/releases/2020/01/200128115421.htm

Air pollution impacts can be heart-stopping

There is an increased risk of out-of-hospital cardiac arrest (OHCA) even from short-term exposure to low concentrations of fine particulate matter PM2.5, an international study has found, noting an association with gaseous pollutants such as those from coal burning/mining, bushfires and motor vehicles.

The nationwide study of data from Japan, chosen for its superior monitoring, population density and relative air quality, is believed to be by far the largest of its kind. It provides comprehensive evidence of the relationship between PM2.5 and cardiac arrests, using a sample three times larger than all previous research combined and demonstrating the impacts on groups such as the elderly.The study led by the University of Sydney concludes that worldwide, standards should be tightened; the implications also point to the need for cleaner energy sources.The findings publish today in the high-impact journal The corresponding and senior author, from the University of Sydney School of Medicine, Professor Kazuaki Negishi, said previous research into air pollution and acute cardiac events had been inconsistent, especially at air concentrations that met or bettered the World Health Organization (WHO) guidelines.Inconsistencies in previous data were addressed through the size and robustness of this study, which found that more than 90 percent of OHCAs occurred at PM2.5 levels lower than the WHO guideline (and Australian standard level), a daily-average of 25 micrograms per cubic metre (?g/m3). As well, 98 percent of OHCAs happened at levels lower than the Japanese or American daily standard level of 35 ?g/m3."Out-of-hospital cardiac arrest is a major medical emergency -- with less than one in 10 people worldwide surviving these events -- and there has been increasing evidence of an association with the more acute air pollution, or fine particulate matter such as PM2.5," said Professor Negishi, a cardiologist and Head of Medicine, Nepean Clinical School, at the Faculty of Medicine and Health."We analysed almost a quarter of a million cases of out-of-hospital cardiac arrests and found a clear link with acute air pollution levels."Our study supports recent evidence that there is no safe level of air pollution -- finding an increased risk of cardiac arrest despite air quality generally meeting the standards."Given the fact that there is a tendency towards worsening air pollution -- from increasing numbers of cars as well as disasters such as bushfires -- the impacts on cardiovascular events, in addition to respiratory diseases and lung cancer -- must be taken into account in health care responses."Professor Negishi, who previously conducted field work after the 2014 massive Hazelwood coal mine fire in Victoria, said that where cardiovascular impacts were concerned, those generally at risk were the elderly: "If you're young and healthy, there should be no immediate risk of devastating consequence." However, he highlights these findings are only in relation to the short-term and that the effects can last for up to five years.The paper concludes that there is an "urgent" need to improve air quality. "As no boundary exists in air quality among countries, a global approach to tackle this crucial health issue is necessary for our planet," the authors state.The study drew upon data from Japan because the country keeps comprehensive records of its air pollution levels as well as a high-quality, nationwide repository of OHCA.The researchers found a 1- 4 percent increased risk associated with every 10 ?g/m3 increase in PM2.5.Put another way, Sydney has recently been experiencing increased air pollution because of bushfire smoke and, on its worst day PM2.5 surpassed the standard of 25 ?g/m3 to jump to more than 500 ?g/m3 in the suburb of Richmond, comparable to levels of continuous cigarette smoking. There are about 15,000 OHCAs annually in Australia so in a hypothetical situation, if there is a 10-unit increase in the daily average of PM2.5, it could lead to another 600 OHCAs resulting in 540 deaths (10% survival rate globally).Also analysed were the impacts regarding sex and age.Although the impacts did not divide along gender lines, for people aged over 65, PM2.5 exposure was significantly associated with incidence of all-cause OHCA.The data revealed an association between short-term exposure to carbon monoxide, photochemical oxidants and sulphur dioxide and all-cause OHCA but not with nitrogen dioxide. Professor Negishi explains that it was likely that the levels of nitrogen dioxide, for example from car emissions, were not high enough to result in OHCA.Adding to known impacts of air pollution on cardiovascular mortality generally, this study plugs important gaps in knowledge about the effects of short-term exposure to acute air pollution on OHCA.The authors state: "Combined with air quality forecasts, our results can be used to predict this emergency condition and to allocate our resources more efficiently."1. Traffic/motor vehicles2. Bushfires (massive annual events in California and the Amazon as well as in Australia)This research is a collaboration between the University of Sydney, the University of Tasmania/Menzies Institute for Medical Research, Monash University, the University Centre for Rural Health in Australia and Gunma University in Japan.

Pollution