Switching to vehicles powered by electricity from renewables could save lives - Video

Use of corn ethanol or electricity from coal worse than gasoline for public health

Driving vehicles that use electricity from renewable energy instead of gasoline could reduce the resulting deaths due to air pollution by 70 percent. This finding comes from a new life cycle analysis of conventional and alternative vehicles and their air pollution-related public health impacts, published Monday, Dec. 15, 2014, in the Proceedings of the National Academy of Sciences.

The study also shows that switching to vehicles powered by electricity made using natural gas yields large health benefits. Conversely, vehicles running on corn ethanol or vehicles powered by coal-based or "grid average" electricity are worse for health; switching from gasoline to those fuels would increase the number of resulting deaths due to air pollution by 80 percent or more.

“These findings demonstrate the importance of clean electricity, such as from natural gas or renewables, in substantially reducing the negative health impacts of transportation,” said Chris Tessum, co-author on the study and a researcher in the Department of Civil, Environmental, and Geo- Engineering in the University of Minnesota’s College of Science and Engineering.

The University of Minnesota team estimated how concentrations of two important pollutants—particulate matter and ground-level ozone—change as a result of using various options for powering vehicles. Air pollution is the largest environmental health hazard in the U.S., in total killing more than 100,000 people per year. Air pollution increases rates of heart attack, stroke, and respiratory disease.

The authors looked at liquid biofuels, diesel, compressed natural gas, and electricity from a range of conventional and renewable sources. Their analysis included not only the pollution from vehicles, but also emissions generated during production of the fuels or electricity that power them. With ethanol, for example, air pollution is released from tractors on farms, from soils after fertilizers are applied, and to supply the energy for fermenting and distilling corn into ethanol.

“Our work highlights the importance of looking at the full life cycle of energy production and use, not just at what comes out of tailpipes,” said Bioproducts and Biosystems Engineering Assistant Professor Jason Hill, co-author of the study. “We greatly underestimate transportation’s impacts on air quality if we ignore the upstream emissions from producing fuels or electricity.”

The researchers also point out that whereas recent studies on life cycle environmental impacts of transportation have focused mainly on greenhouse gas emissions, it is also important to consider air pollution and health. Their study provides a unique look at where life cycle emissions occur, how they move in the environment, and where people breathe that pollution. Their results provide unprecedented detail on the air quality-related health impacts of transportation fuel production and use.

“Air pollution has enormous health impacts, including increasing death rates across the U.S.,” said Civil, Environmental and Geo- Engineering Associate Professor Julian Marshall, co-author on this study. “This study provides valuable new information on how some transportation options would improve or worsen those health impacts.”

The study’s authors are Marshall and Tessum (College of Science and Engineering) and Hill (College of Food, Agricultural and Natural Resource Sciences), at the University of Minnesota. Marshall and Hill are also Resident Fellows of the University’s Institute on the Environment. This research was supported by the University of Minnesota’s Initiative for Renewable Energy and the Environment (IREE), the Office of Energy Efficiency & Renewable Energy of the U.S. Dept. of Energy (EERE/DOE), and the Agricultural and Food Research Initiative of the U.S. Dept. of Agriculture (USDA/AFRI).

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Source: University of Minnesota

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Switching to vehicles powered by electricity from renewables could save lives

Driving vehicles that use electricity from renewable energy instead of gasoline could reduce the resulting deaths due to air pollution by 70 percent. Credit: © Dmitry Vereshchagin / Fotolia

Driving vehicles that use electricity from renewable energy instead of gasoline could reduce the resulting deaths due to air pollution by 70 percent. This finding comes from a new life cycle analysis of conventional and alternative vehicles and their air pollution-related public health impacts, published Monday, Dec. 15, 2014, in the Proceedings of the National Academy of Sciences.

The study also shows that switching to vehicles powered by electricity made using natural gas yields large health benefits. Conversely, vehicles running on corn ethanol or vehicles powered by coal-based or "grid average" electricity are worse for health; switching from gasoline to those fuels would increase the number of resulting deaths due to air pollution by 80 percent or more.

"These findings demonstrate the importance of clean electricity, such as from natural gas or renewables, in substantially reducing the negative health impacts of transportation," said Chris Tessum, co-author on the study and a researcher in the Department of Civil, Environmental, and Geo- Engineering in the University of Minnesota's College of Science and Engineering.

The University of Minnesota team estimated how concentrations of two important pollutants -- particulate matter and ground-level ozone -- change as a result of using various options for powering vehicles. Air pollution is the largest environmental health hazard in the U.S., in total killing more than 100,000 people per year. Air pollution increases rates of heart attack, stroke, and respiratory disease.

The authors looked at liquid biofuels, diesel, compressed natural gas, and electricity from a range of conventional and renewable sources. Their analysis included not only the pollution from vehicles, but also emissions generated during production of the fuels or electricity that power them. With ethanol, for example, air pollution is released from tractors on farms, from soils after fertilizers are applied, and to supply the energy for fermenting and distilling corn into ethanol.

"Our work highlights the importance of looking at the full life cycle of energy production and use, not just at what comes out of tailpipes," said Bioproducts and Biosystems Engineering Assistant Professor Jason Hill, co-author of the study. "We greatly underestimate transportation's impacts on air quality if we ignore the upstream emissions from producing fuels or electricity."

The researchers also point out that whereas recent studies on life cycle environmental impacts of transportation have focused mainly on greenhouse gas emissions, it is also important to consider air pollution and health. Their study provides a unique look at where life cycle emissions occur, how they move in the environment, and where people breathe that pollution. Their results provide unprecedented detail on the air quality-related health impacts of transportation fuel production and use.

"Air pollution has enormous health impacts, including increasing death rates across the U.S.," said Civil, Environmental and Geo- Engineering Associate Professor Julian Marshall, co-author on this study. "This study provides valuable new information on how some transportation options would improve or worsen those health impacts."

Source: University of Minnesota

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What's in the grime tarnishing the Taj Mahal?

Taj Mahal

Every several years, workers apply a clay mask to India's iconic but yellowing Taj Mahal to remove layers of grime and reveal the white marble underneath. Now scientists are getting to the bottom of what kinds of pollutants are discoloring one of the world's celebrated wonders. Their findings, published in the ACS journal Environmental Science & Technology, could help inform efforts to protect the mausoleum and other surfaces from pollution.

Mike H. Bergin, Sachchida Nand Tripathi and colleagues note that Indian officials have tried to reduce the effects of pollution on the Taj Mahal by restricting nearby traffic and limiting local industrial emissions. But despite regulations and an occasional deep clean, the domes and minarets continue to accrue a layer of soot. So far, no published studies have looked closely at what specific compounds are causing it to appear yellow. Bergin's and Tripathi's teams wanted to find out.

The researchers analyzed particles in the air and on marble samples near the main dome over several months. Using a novel method they developed, the team estimated how these specks reflect light and therefore affect the color of the building. They conclude that black carbon and brown carbon from the burning of trash, fuels and other materials are among the primary pollutants tarnishing the Taj Mahal. In the future, their approach could be used to craft strategies to address the chronic yellowing and improve air quality, they say.

The authors acknowledge funding from the Indo-U.S. Science and Technology Forum, the Environmental Protection Agency and the National Science Foundation.

Source: American Chemical Society

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Pilot plant for removal of extreme gas charges from deep waters

Pit Lake Guadiana in the former mining area Herrerias in Andalusia, Spain.
Credit: : Bertram Boehrer/UFZ

Being part of the mining area Herrerias in Andalusia, deep waters of Pit Lake Guadiana show extremely high concentration of dissolved carbon dioxide (CO2). In the case of a spontaneous ebullition, human beings close-by would be jeopardized. To demonstrate the danger and the possible solution, scientists of the Spanish Institute of Geology and Mining, the University of the Basque Country (UPV/EHU, Bilbao) and the Helmholtz Centre for Environmental Research (UFZ) constructed a pilot plant for degassing. A fountain pulls deep water through a pipe to the surface, where the gas can escape from the water. The buoyancy produced by the bubbles provides the energy required for driving the flow.

"The deep water in the residual lake Guadiana contains an extremely high volume of carbon dioxide (CO2). Oxidation of ores has created a very acidic milieu, which is also known from other mining areas. In the mining area Herrerias however, this acidity dissolves carbonate from the rocks and produces carbonic acid (dissolved CO2), which can be accumulated under the high pressures of deep waters in the lake. There is not much circulation beyond 25 meter depth to remove the gas load" says Dr. Bertram Boehrer of UFZ, who is physicist and has been investigating stratification in lakes at many places on Earth. Due to the high hydrostatic pressure, each liter of deep water contains about 2.5 liters of CO2 gas. As long as the stratification remains stable, the gas is retained in the deep water. A land slide or other processes producing large water movements could facilitate a sudden release of gas previously confined under high pressure. Inhaled air of 8 percent CO2 are considered deadly for humans.

Now the scientists installed a degasing pipe which is the heart of the new pilot plant: Deep water enters a pipe at 61m depth. On the way up, hydrostatic pressure drops and gas bubbles form. The reduced density of the water-gas-mixture allows that deep water is pushed out of the pipe at the upper end to form a fountain above the water table, where gas is released to the atmosphere. This is an elegant solution, as the system does not require any additional driver, and the controlled release of CO2 does not pose any problem. "With this pilot plant, we could demonstrate that this approach also works in Guadiana pit lake. This can now be proposed to authorities as a possible approach to deal with the gas load." Though the lake in the mining area is fenced and access is not permitted to the public, this prohibition is difficult to survey.

Earlier installations in Lake Nyos in Cameroon served as a good example for this approach. In this lake, degassing pipes had been installed, which released the gas load with three fountains. On August 21st 1986, a large volume of gas escaped from the lake suddenly. The gas entered valleys of the surrounding area. 1700 human beings and thousands of animals were killed. The trigger could have been a land slide though this was never really proven. To avoid a repetition of this disaster, the gas load is slowly removed from the lake. One more crater lake called Monoun in Cameroon suffocated 37 human beings close to its shores in a similar eruption. Also in Monoun degasing fountains have been installed.

In Guadiana pit lake we do not see the same danger as in Lake Nyos, due to smaller size and depth. In addition, a density gradient between surface waters and deep waters is keeping the system stable. However, gas concentrations are so high that precaution must be taken. More detailed investigations must be implemented and remediation must be considered, says Dr. Boehrer. For the formation of such extreme gas loads, lakes must be sufficiently deep with incomplete winter recirculation (meromixis) and a strong carbon dioxide source. At the moment, we do not have such a lake in Germany.

Source: Helmholtz Centre for Environmental Research - UFZ

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When you lose weight, where does the fat go? Most of the mass is breathed out as carbon dioxide, study shows

Despite a worldwide obsession with diets and fitness regimes, many health professionals cannot correctly answer the question of where body fat goes when people lose weight.
Credit: © Lovrencg / Fotolia

Despite a worldwide obsession with diets and fitness regimes, many health professionals cannot correctly answer the question of where body fat goes when people lose weight, a UNSW Australia study shows.

The most common misconception among doctors, dieticians and personal trainers is that the missing mass has been converted into energy or heat.

"There is surprising ignorance and confusion about the metabolic process of weight loss," says Professor Andrew Brown, head of the UNSW School of Biotechnology and Biomolecular Sciences.

"The correct answer is that most of the mass is breathed out as carbon dioxide. It goes into thin air," says the study's lead author, Ruben Meerman, a physicist and Australian TV science presenter.

In their paper, published in the British Medical Journal today, the authors show that losing 10 kilograms of fat requires 29 kilograms of oxygen to be inhaled and that this metabolic process produces 28 kilograms of carbon dioxide and 11 kilograms of water.

Mr Meerman became interested in the biochemistry of weight loss through personal experience.

"I lost 15 kilograms in 2013 and simply wanted to know where those kilograms were going. After a self-directed, crash course in biochemistry, I stumbled onto this amazing result," he says.

"With a worldwide obesity crisis occurring, we should all know the answer to the simple question of where the fat goes. The fact that almost nobody could answer it took me by surprise, but it was only when I showed Andrew my calculations that we both realised how poorly this topic is being taught."

The authors met when Mr Meerman interviewed Professor Brown in a story about the science of weight loss for the Catalyst science program on ABC TV in March this year.

"Ruben's novel approach to the biochemistry of weight loss was to trace every atom in the fat being lost and, as far as I am aware, his results are completely new to the field," says Professor Brown.

"He has also exposed a completely unexpected black hole in the understanding of weight loss amongst the general public and health professionals alike."

If you follow the atoms in 10 kilograms of fat as they are 'lost', 8.4 of those kilograms are exhaled as carbon dioxide through the lungs. The remaining 1.6 kilograms becomes water, which may be excreted in urine, faeces, sweat, breath, tears and other bodily fluids, the authors report.

"None of this is obvious to people because the carbon dioxide gas we exhale is invisible," says Mr Meerman.

More than 50 per cent of the 150 doctors, dieticians and personal trainers who were surveyed thought the fat was converted to energy or heat.

"This violates the Law of Conservation of Mass. We suspect this misconception is caused by the energy in/energy out mantra surrounding weight loss," says Mr Meerman.

Some respondents thought the metabolites of fat were excreted in faeces or converted to muscle.

"The misconceptions we have encountered reveal surprising unfamiliarity about basic aspects of how the human body works," the authors say.

One of the most frequently asked questions the authors have encountered is whether simply breathing more can cause weight loss. The answer is no. Breathing more than required by a person's metabolic rate leads to hyperventilation, which can result in dizziness, palpitations and loss of consciousness.

The second most frequently asked question is whether weight loss can cause global warming.

"This reveals troubling misconceptions about global warming which is caused by unlocking the ancient carbon atoms trapped underground in fossilised organisms. The carbon atoms human beings exhale are returning to the atmosphere after just a few months or years trapped in food that was made by a plant," says Mr Meerman, who also presents the science of climate change in high schools around Australia.

Mr Meerman and Professor Brown recommend that these basic concepts be included in secondary school curricula and university biochemistry courses to correct widespread misconceptions about weight loss among lay people and health professionals.

Source: University of New South Wales

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2014 Antarctic ozone hole holds steady

This image shows ozone concentrations above Antarctica on Sept. 11, 2014. Credit: NASA

The single-day maximum area was similar to that in 2013, which reached 24.0 million square kilometers (9.3 million square miles). The largest single-day ozone hole ever recorded by satellite was 29.9 million square kilometers (11.5 million square miles) on Sept. 9, 2000. Overall, the 2014 ozone hole is smaller than the large holes of the 1998-2006 period, and is comparable to 2010, 2012, and 2013.

With the increased atmospheric chlorine levels present since the 1980s, the Antarctic ozone hole forms and expands during the Southern Hemisphere spring (August and September). The ozone layer helps shield life on Earth from potentially harmful ultraviolet radiation that can cause skin cancer and damage plants.

The Montreal Protocol agreement beginning in 1987 regulated ozone depleting substances, such as chlorine-containing chlorofluorocarbons and bromine-containing halons. The 2014 level of these substances over Antarctica has declined about 9 percent below the record maximum in 2000.

"Year-to-year weather variability significantly impacts Antarctica ozone because warmer stratospheric temperatures can reduce ozone depletion," said Paul A. Newman, chief scientist for atmospheres at NASA's Goddard Space Flight Center in Greenbelt, Maryland. "The ozone hole area is smaller than what we saw in the late-1990s and early 2000s, and we know that chlorine levels are decreasing. However, we are still uncertain about whether a long-term Antarctic stratospheric temperature warming might be reducing this ozone depletion."

Scientists are working to determine if the ozone hole trend over the last decade is a result of temperature increases or chorine declines. An increase of stratospheric temperature over Antarctica would decrease the ozone hole's area. Satellite and ground-based measurements show that chlorine levels are declining, but stratospheric temperature analyses in that region are less reliable for determining long-term trends.

Scientists also found that the minimum thickness of ozone layer this year was recorded at 114 Dobson units on Sept. 30, compared to 250-350 Dobson units during the 1960s. Over the last 50 years satellite and ground-based records over Antarctica show ozone column amounts ranging from 100 to 400 Dobson units, which translates to about 1 millimeter (1/25 inch) to 5 millimeters (1/6 inch) of ozone in a layer if all of the ozone were brought down to the surface.

The ozone data come from the Dutch-Finnish Ozone Monitoring Instrument on NASA's Aura satellite and the Ozone Monitoring and Profiler Suite instrument on the NASA-NOAA Suomi National Polar-orbiting Partnership satellite. NOAA measurements at South Pole station monitor the ozone layer above that location by means of Dobson spectrophotometer and regular ozone-sonde balloon launches that record the thickness of the ozone layer and its vertical distribution. Chlorine amounts are estimated using NOAA and NASA ground measurements and observations from the Microwave Limb Sounder aboard NASA's Aura satellite.

NASA and NOAA are mandated under the Clean Air Act to monitor ozone-depleting gases and stratospheric depletion of ozone. Scientists from NASA and NOAA have been monitoring the ozone layer and the concentrations of ozone-depleting substances and their breakdown products from the ground and with a variety of instruments on satellites and balloons since the 1970s. These observations allow us to provide a continuous long-term record to track the long-term and year-to-year evolution of ozone amounts.

Source:  NASA/Goddard Space Flight Center

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Clearing tropical rainforests distorts Earth's wind and water systems, packs climate wallop beyond carbon

The world without tropical rainforests. Credit: Image courtesy of ClimateFocus

A new study released today presents powerful evidence that clearing trees not only spews carbon into the atmosphere, but also triggers major shifts in rainfall and increased temperatures worldwide that are just as potent as those caused by current carbon pollution. Further, the study finds that future agricultural productivity across the globe is at risk from deforestation-induced warming and altered rainfall patterns.

The report, "Effects of Tropical Deforestation on Climate Change and Agriculture," published today in Nature Climate Change and released in collaboration with Climate Focus provides the most comprehensive analysis to date of the climate impacts of tropical forest destruction on agriculture in the tropics and thousands of miles away. Specifically, the study finds that deforestation in South America, Southeast Asia and Africa may alter growing conditions in agricultural areas in the tropics and as far away as the US Midwest, Europe and China.

The study is also the only global synthesis of research based on cutting-edge climate models and empirical data on the direct local, regional and global impacts of cutting down tropical forests, which regulate interactions between the earth and the atmosphere. It predicts that atmospheric impacts resulting from complete tropical deforestation could lead to a rise in global temperature of 0.7 degrees Celsius (on top of the impact from greenhouse gases), which would double the observed global warming since 1850. Currently, climate change negotiators are shaping policies that focus on greenhouse gases, in particular carbon. To date, they have overlooked policy responses that address other ways that forests affect climate.

"Tropical deforestation delivers a double whammy to the climate -- and to farmers," said Deborah Lawrence, Professor of Environmental Sciences at the University of Virginia, the study's lead author. "Most people know that climate change is a dangerous global problem, and that it's caused by pumping carbon into the atmosphere. But it turns out that removing forests alters moisture and air flow, leading to changes -- from fluctuating rainfall patterns to rises in temperatures -- that are just as hazardous, and happen right away. The impacts go beyond the tropics -- the United Kingdom and Hawaii could see an increase in rainfall while the US Midwest and Southern France could see a decline."

The report presents compelling evidence that tropical deforestation is already affecting local and regional climates. Meteorological data, for example, show that in Thailand, the beginning of the dry season is experiencing less rainfall due to deforestation. And in parts of the Amazon, the world's largest stretch of rainforest, the timing of once-predictable rainfall has shifted due to deforestation. In deforested regions, the wet season is delayed by two weeks; in forested regions, there are no changes.

"The study not only compiles highly relevant scientific literature, it will also help guide policy makers working on climate change. Tropical deforestation impacts weather patterns globally, which makes addressing deforestation one of the most important mitigation strategies," adds Dr. Charlotte Streck, Director of Climate Focus.

Globalized Impacts of Deforestation

"Teleconnections," associated with the mass movement of air and conditions in the upper atmosphere, have the potential to extend the impacts of tropical deforestation on climate globally. An increase in temperature in the tropics due to deforestation generates large upward-moving air masses. When these hit the upper atmosphere they cause ripples, or teleconnections, that flow outward in various directions, similar to the way in which an underwater earthquake can create a tsunami.

Models examined in the study showed that increased or complete deforestation could put the climate in some of the world's most important agriculture regions off kilter. These variations in rainfall and spikes in temperature could occur across the world, according to the report.

For example, complete deforestation of the Amazon Basin would likely reduce rainfall in the US Midwest, Northwest and parts of the south during the agricultural season. The complete deforestation of Central Africa would likely cause declines in rainfall in the Gulf of Mexico and parts of the US Midwest and Northwest and increase it on the Arabian Peninsula. There could also be precipitation declines in Ukraine and Southern Europe.

"While complete deforestation is unlikely to occur, over the course of history, deforestation has continued as countries develop," Lawrence said. "Further, this study fills gaps in our understanding of deforestation tipping points -- and what could happen if we continue down this path."

Turning up the heat, turning down the rain

Across the board, the study reports, deforestation poses risks to agriculture by causing an increase in average temperature, a decline in average rainfall and a change in the location and timing of rainfall. Deforestation, for example, would lead to a reduction in rainfall between 10-15 percent in the region surrounding where the deforestation took place.

According to Lawrence, there is almost always an increase in temperature with deforestation. "This does not change, no matter what you do -- no matter what kind of model you use, temperature increases occur -- whether it's half a degree, a full degree or two degrees."

"That's a very big deal," said Lawrence. "In the last few centuries, the average global temperature has never varied by more than about one degree. Once we go above one degree -- to 1.5 degrees or more -- we're talking about conditions that are very different from anything humanity has ever experienced." Because crops are highly sensitive to changes in temperature and moisture, she added, they would suffer in hotter conditions. Increased floods or decreases in soil moisture would further add to stress on crops.

"Farmers, so reliant on consistent and reliable growing conditions, could lose their bearings and even their incomes, when facing these ups and downs in temperature and rainfall," Lawrence said. "While farmers may ultimately adapt to shifts in the season, it's difficult -- if not impossible -- for farmers to adapt to increased floods or parched soils."

Forests: Not Lungs but Sweat Glands

Because forests turn water from soil into moisture in the air, they cool the atmosphere above them. Tropical forests move more water than any other ecosystem on land. They are central to the earth's process of generating and regenerating moisture, so clearing ever-larger swathes of forest eventually leads to a drying and warming effect. By disturbing the movement of air in remote parts of the atmosphere, tropical deforestation throws temperature and rainfall patterns worldwide out of whack.

The impact of deforestation is diverse and varies across regions and scales -- from small plots of farmland in the midst of the rainforest to large swathes of cattle pasture bordered by forests -- but the more deforestation that occurs, the greater the impact.

"Tropical forests are often talked about as the 'lungs of the earth,' but they're more like the sweat glands," said Lawrence. "They give off a lot of moisture, which helps keep the planet cool. That crucial function is lost -- and even reversed -- when forests are destroyed."

The study found that relatively small plots of deforestation can actually increase rainfall at a local scale. There is, however, a critical clearing size above which rainfall declines dramatically.

Models studied in the report show that in the Amazon and, possibly, in the Congo Basin, 30-50 percent may be the deforestation tipping point. Any additional forest clearing would lead to rainfall reductions that could significantly change ecosystems, and compound the risk of additional dangers, such as an increase in forest fires.

The location of deforested areas can also affect their impacts on regional climates, the study finds. Deforesting West Africa or the Congo could reduce rainfall across the region by 40-50% and increase temperatures there up to 3°C. Regional scale models project that in the Amazon Basin, clearing 40% of the forest would decrease wet-season rainfall by 12% and dry-season rainfall by 21%. It would also reduce by 4% rainfall in the Rio de la Plata Basin, a center for soy, corn and wheat production, thousands of miles south of the Amazon. Because Southeast Asia is surrounded by oceans, the impact of deforestation on regional temperatures and rainfall may be less severe.

To reduce the effects of deforestation on climate change, the data suggest it would be best to retain large swathes of forest across the tropical forest belt and to avoid large-scale deforestation in any single location.

Lawrence added that climate-change negotiators and other policymakers should take the impacts of deforestation seriously. "What happens on the surface of the earth (in terms of changes in vegetation) is a big factor in climate change. We ignore it at our own peril."

Source: ClimateFocus

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Easy measurement of the effect of fine dust

The Karlsruhe Exposure System is compact and can measure fine dust concentrations directly at the location of pollution. Credit: VITROCELL Systems GmbH

Fine dusts from industry, traffic, and households are omnipresent. Still, they are difficult to capture by reliable medical measurements. KIT researchers have now developed an exposure system, by means of which biological cells are exposed to fine dust-loaded air flows in an exact and reproducible manner. Using this system, it is possible to collect data on the adverse impact of fine dusts of variable sources in a rapid and inexpensive manner and without animal experiments being needed. In cooperation with the industry partner Vitrocell, a marketable product has been developed.

"Fine dusts may be carbon black from diesel engines, sea salt on the coast, natural dusts, or intermediate products of chemical industry," Dr. Hanns-Rudolf Paur and Sonja Mülhopt of Karlsruhe Institute of Technology explain. All dust grains smaller than 10 µm, i.e. one hundredth of a millimeter, are considered to be fine dust irrespective of their chemical composition. Dust particles smaller than 10 µm easily pass the upper respiratory tract of man. "They deposit in the pulmonary alveoli and may damage the lungs due to their chemical or physical properties."

To study the effects in detail, lung cells and fine dust have to be brought together in a realistic environment. Ultimately, the processes taking place in the human body from the nose to the lungs have to be reproduced. For this purpose, the air containing the fine dust is heated up to body temperature by the Karlsruhe Exposure System. The air flow is provided with about 85% humidity and reduced to the air flow rate of the lungs. For a long-term measurement series, these conditions have to be maintained exactly and reproducibly. Finally, the particle flow passes lung cell cultures cultivated with nutrient medium. 

Depending on the type of fine dust, these cultures subsequently show symptoms of inflammation, oxidation stress, or membrane damage. In parallel, the deposited particle dose is recorded by means of a precision balance.

The new Exposure System is much closer to reality than previous methods that collected fine dust from air or exhaust gas and stirred it into the nutrient liquid. At the same time, the Exposure System works more rapidly for many applications and is cheaper than a study based on animal experiments. Thanks to its compactness, the Karlsruhe Exposure System can also be used for measurements at the place of fine dust development or pollution. "The limitations of conventional methods were overcome by the close, interdisciplinary cooperation of biologists and process engineers at KIT," the Head of the project, Sonja Mülhopt, says. "With the Karlsruhe Exposure System, we now have a technology that will improve the protection of the environment and mankind."

"Research at KIT was the basis of a process with a high industry potential," Tobias Krebs of the company Vitrocell Systems (Waldkirch) says. "Together, we now plan to commercialize this product." The impact of fine dusts plays an important role in fundamental research as well as in many areas of application. According to the EU Directive on Chemicals REACH, chemical industry is obliged to classify its products in various hazard categories. 

Manufacturers of lung medicine, such as asthma sprays, are now enabled to test new substances in a close-to-reality manner. New and old biomass fuels may also be relevant fine dust sources.

Source:  Karlsruhe Institute of Technology

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Fracking and pollution: Technology-dependent emissions of gas extraction in the US

The KIT measurement instrument on board of a minivan directly measures atmospheric emissions on site with a high temporal resolution.
Credit: Photo: F. Geiger/KIT

Not all boreholes are the same. Scientists of the Karlsruhe Institute of Technology (KIT) used mobile measurement equipment to analyze gaseous compounds emitted by the extraction of oil and natural gas in the USA. For the first time, organic pollutants emitted during a fracking process were measured at a high temporal resolution using a vapor capture system. The highest values measured by this process exceeded typical mean values in urban air by a factor of about one thousand, as was reported in the ACP journal.

Emission of trace gases by oil and gas fields was studied by the KIT researchers in the USA (Utah and Colorado) together with US institutes. Background concentrations and the waste gas plumes of single extraction plants and fracking facilities were analyzed. The air quality measurements of several weeks duration took place under the "Uintah Basin Winter Ozone Study" coordinated by the National Oceanic and Atmospheric Administration (NOAA).

The KIT measurements focused on health-damaging aromatic hydrocarbons in air, such as carcinogenic benzene. Maximum concentrations were determined in the waste gas plumes of boreholes. Some extraction plants emitted up to about a hundred times more benzene than others. The highest values of some milligrams of benzene per cubic meter air were measured downstream of an open fracking facility, where returning drilling fluid is stored in open tanks and basins. Much better results were reached by oil and gas extraction plants and plants with closed production processes. In Germany, benzene concentration at the workplace is subject to strict limits: The Federal Emission Control Ordinance gives an annual benzene limit of five micrograms per cubic meter for the protection of human health, which is smaller than the values now measured at the open fracking facility in the US by a factor of about one thousand. The researchers published the results measured in the journal Atmospheric Chemistry and Physics ACP.

"Characteristic emissions of trace gases are encountered everywhere. These are symptomatic of gas and gas extraction. But the values measured for different technologies differ considerably," Felix Geiger of the Institute of Meteorology and Climate Research (IMK) of KIT explains. He is one of the first authors of the study. By means of closed collection tanks and so-called vapor capture systems, for instance, the gases released during operation can be collected and reduced significantly.

"The gas fields in the sparsely populated areas of North America are a good showcase for estimating the range of impacts of different extraction and fracking technologies," explains Professor Johannes Orphal, Head of IMK. "In the densely populated Germany, framework conditions are much stricter and much more attention is paid to reducing and monitoring emissions."

Fracking is increasingly discussed as a technology to extract fossil resources from unconventional deposits. Hydraulic breaking of suitable shale stone layers opens up the fossil fuels stored there and makes them accessible for economically efficient use. For this purpose, boreholes are drilled into these rock formations. Then, they are subjected to high pressure using large amounts of water and auxiliary materials, such as sand, cement, and chemicals. The oil or gas can flow to the surface through the opened microstructures in the rock. Typically, the return flow of the aqueous fracking liquid with the dissolved oil and gas constituents to the surface lasts several days until the production phase proper of purer oil or natural gas. This return flow is collected and then reused until it finally has to be disposed of. Air pollution mainly depends on the treatment of this return flow at the extraction plant. In this respect, currently practiced fracking technologies differ considerably. For the first time now, the resulting local atmospheric emissions were studied at a high temporary resolution. Based on the results, emissions can be assigned directly to the different plant sections of an extraction plant. For measurement, the newly developed, compact, and highly sensitive instrument, a so-called proton transfer reaction mass spectrometer (PTR-MS), of KIT was installed on board of a minivan and driven closer to the different extraction points, the distances being a few tens of meters. In this way, the waste gas plumes of individual extraction sources and fracking processes were studied in detail.

Source: Karlsruhe Institute of Technology

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Switching to vehicles powered by electricity from renewables could save lives

Driving vehicles that use electricity from renewable energy instead of gasoline could reduce the resulting deaths due to air pollution by 70 percent. Credit: © Dmitry Vereshchagin / Fotolia

Driving vehicles that use electricity from renewable energy instead of gasoline could reduce the resulting deaths due to air pollution by 70 percent. This finding comes from a new life cycle analysis of conventional and alternative vehicles and their air pollution-related public health impacts, published Monday, Dec. 15, 2014, in the Proceedings of the National Academy of Sciences.

The study also shows that switching to vehicles powered by electricity made using natural gas yields large health benefits. Conversely, vehicles running on corn ethanol or vehicles powered by coal-based or "grid average" electricity are worse for health; switching from gasoline to those fuels would increase the number of resulting deaths due to air pollution by 80 percent or more.

"These findings demonstrate the importance of clean electricity, such as from natural gas or renewables, in substantially reducing the negative health impacts of transportation," said Chris Tessum, co-author on the study and a researcher in the Department of Civil, Environmental, and Geo- Engineering in the University of Minnesota's College of Science and Engineering.

The University of Minnesota team estimated how concentrations of two important pollutants -- particulate matter and ground-level ozone -- change as a result of using various options for powering vehicles. Air pollution is the largest environmental health hazard in the U.S., in total killing more than 100,000 people per year. Air pollution increases rates of heart attack, stroke, and respiratory disease.

The authors looked at liquid biofuels, diesel, compressed natural gas, and electricity from a range of conventional and renewable sources. Their analysis included not only the pollution from vehicles, but also emissions generated during production of the fuels or electricity that power them. With ethanol, for example, air pollution is released from tractors on farms, from soils after fertilizers are applied, and to supply the energy for fermenting and distilling corn into ethanol.

"Our work highlights the importance of looking at the full life cycle of energy production and use, not just at what comes out of tailpipes," said Bioproducts and Biosystems Engineering Assistant Professor Jason Hill, co-author of the study. "We greatly underestimate transportation's impacts on air quality if we ignore the upstream emissions from producing fuels or electricity."

The researchers also point out that whereas recent studies on life cycle environmental impacts of transportation have focused mainly on greenhouse gas emissions, it is also important to consider air pollution and health. Their study provides a unique look at where life cycle emissions occur, how they move in the environment, and where people breathe that pollution. Their results provide unprecedented detail on the air quality-related health impacts of transportation fuel production and use.

"Air pollution has enormous health impacts, including increasing death rates across the U.S.," said Civil, Environmental and Geo- Engineering Associate Professor Julian Marshall, co-author on this study. "This study provides valuable new information on how some transportation options would improve or worsen those health impacts."

Source: University of Minnesota

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Updating air pollution measurement methods

Launching a natural research experiment in Kathmandu, Nepal, this month using advanced monitoring methods to assess health risk from air pollution, environmental health scientist Rick Peltier at the University of Massachusetts Amherst hopes to demonstrate for the first time in a real-world setting that air pollution can and should be regulated based on toxicology variables rather than simply on the volume of particles in the air.

Recent technological advances in air quality measurement methods now make it possible and practical to monitor air pollution in a much more sophisticated way than before, Peltier says. Researchers now use X-ray fluorescence spectrometry to measure air pollution metal content, ion chromatography to identify other chemicals and other tactics to assess organic and elemental carbon levels.

Peltier says, "We're interested in how air pollution directly affects health. The current regulatory method doesn't take into account the relative toxicity of components, that is the specific chemical makeup of the air we breathe. There has been a void in the science in this field. But with this experiment, for the first time we'll have biological measurements coupled with high-quality air pollution measurements in a cohort of traffic police exposed to extreme levels of pollution."

At present, the Environmental Protection Agency monitors air quality components every three days at 350 stations across the United States, but there are no such sites in Nepal. Particulates are an important signature of traffic. A poor air quality day in Los Angeles may see 40-50 micrograms of particulates per cubic meter, Peltier says, while in Kathmandu the level can be 800-900, or about 20 times worse.

Ethically, the environmental scientist adds, it would be impossible to expose people to such pollution levels in a laboratory-based experiment, and ambient levels such as those typically observed in Kathmandu are never routinely encountered anywhere in the United States. Peltier and colleagues' study will take advantage of the fact that the traffic officers already are exposed to high air pollution levels in their normal workday.

Funded by a multinational partnership led by UMass Amherst and including the Himalayan region's Intergovernmental Centre for Integrated Mountain Development (ICIMOD) and the Institute for Advanced Sustainability Studies in Potsdam, Germany, the investigation will follow a cohort of 32 traffic control officers in Kathmandu during two seasons: Cold, dry winter from this month into March, with a second study in the hot, rainy monsoon season from June to August, when air pollution levels are lower.

Peltier observes that Nepal's capital city region has poor air quality because two-stroke gasoline and diesel engines, high pollutant emitters, are common. Also, people heat their homes with coal and kerosene and routinely burn garbage and tires outdoors. For the 3 million inhabitants this poses substantial, demonstrable health risks.

"Unfortunately, the Kathmandu metropolitan area has quite poor air quality, and it's in a valley so it is a persistent problem," he adds. "We hypothesize that toxicity is related to the chemical components of pollution. We know this is true in a Petri dish, but now we'll be able to measure it in study subjects."
Participants are 16 men and 16 women, 25 to 35 years old who have similar education and income levels. For a six-day work week, each will carry a small waist pack containing research-grade, solar-powered portable air samplers. The filters will be collected for airborne metals, ions, organic carbon and black carbon analysis. The experiment will include an intervention component, as well: For half of each study week, participants will wear high-quality, particle-filtering face masks that greatly reduce air pollution exposure.

In addition to the air filters, researchers will collect blood samples and ask the traffic officers to use a spirometer several times a day to assess lung function. Their location, activity and electrocardiogram will be continuously measured in both conditions: Breathing polluted air with and without protective face masks.

Air quality samples and the health measurement data will be analyzed at UMass Amherst and compared between the different exposure conditions. Peltier and his postdoctoral fellow Kabindra Shakya will collaborate with researcher Arnico Panday of ICIMOD, Kathmandu, which along with UMass Amherst supported the work, plus Maheswar Rupakheti of the sustainability institute in Potsdam.

Source: University of Massachusetts 

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