Grantee Research Project Results
2010 Progress Report: Health Effects Institute (2010-2015)
EPA Grant Number: R834677Center: Health Effects Institute (Prior to 2000)
Center Director: Greenbaum, Daniel S.
Title: Health Effects Institute (2010-2015)
Investigators: Greenbaum, Daniel S.
Institution: Health Effects Institute
EPA Project Officer: Chung, Serena
Project Period: April 1, 2010 through March 31, 2015
Project Period Covered by this Report: April 1, 2010 through March 31,2011
Project Amount: $25,000,000
RFA: Health Effects Institute (2010) RFA Text | Recipients Lists
Research Category: Human Health , Air Quality and Air Toxics , Air
Objective:
The Health Effects Institute (HEI) is an independent, nonprofit organization chartered in 1980 to provide high-quality, impartial, and relevant science regarding the effects of air pollution on health. Supported jointly by the U.S. Environmental Protection Agency (EPA) and industry, and periodically by other domestic and international partners, HEI provides science to inform decisions that are directly relevant to regulation and other actions to improve air quality.Progress Summary:
A HEALTHIER ENERGY FUTURE AT HOME
Since its inception, HEI has been evaluating the health effects of fuels, fuel additives, and new energy technologies so that as society attempts to solve one set of pollution problems, it does not unintentionally create others. As the search for new fuels and engines increases — driven by air pollution regulations, climate change, energy independence, and a worldwide increase in demand — so does the need for the credible, forward-thinking health science that HEI supports.
In the past 50 years, the cars we drive and the trucks that carry our goods have changed dramatically. Catalytic converters remove hazardous pollutants from emissions, and modern engines have become more efficient. Lead and, increasingly, sulfur have been removed from petroleum fuels. Still, as travel grows, mobile sources remain important emitters of air pollution and greenhouse gases.
Cars of the Future
Until recently, one thing has remained the same for nearly a century. Almost all of the motor vehicles on the road have run on gasoline- and diesel-powered internal combustion engines.
Today’s new cars, however, include hybrids and electric cars and run on a host of new fuels. Some projections suggest that with new policies and incentives, the change of scene will be so complete that, by the middle of this century, nearly every conventional car on the road today could be replaced with vehicular technology that has not yet hit the pavement.
Rules of the Future
Concerns about the health effects of motor vehicle emissions have led to the introduction of innovative pollution control approaches, including cleaner fuels and engine technologies. More recently, regulations have begun to extend beyond traditional air pollutants. For instance, California has committed to reducing its greenhouse gas emissions by 30% from 1990 levels by 2020, with mandatory caps and regulations to reduce passenger car emissions to begin in 2012. Europe has also moved forward with increasingly strict emissions standards. In 2010, the U.S. government began to mirror the California efforts and mandated that cleaner, more efficient cars and trucks be deployed by 2016, with a further round of requirements for 2025 in preparation. Recent laws and financial incentives also encourage deployment of advanced vehicles such as electric cars.
Technologies of the Future
With these forces in play, what kinds of vehicles will populate the U.S. roadways in the coming decades? And what will be under the hood? According to HEI’s Special Committee on Emerging Technologies (SCET), it is very likely that our near-term future will include many fuels: ethanol, biodiesel, and other renewable fuels, in addition to new forms of gasoline and diesel. In its comprehensive report of the likely changes, SCET — a distinguished panel of experts drawn from academia, government, industry, and the environmental community — also noted that the internal combustion engine will likely endure during the coming decade or two, although it will be supplemented and could eventually be superseded by the electric power train.
During this transitional period, new technologies, such as gasoline direct injection, turbocharging, engine downsizing, and diesel emissions reduction systems, will become more commonplace. These technologies will help increase fuel efficiency — which means less carbon dioxide emissions per mile.
The use of ethanol, which is widely used in a blend with gasoline, is increasing and is projected to grow under legislative mandates. Some newer flex-fuel engines allow for higher concentrations of ethanol. As cars burn this new fuel, their emissions profiles will shift — with some advantages (e.g., reducing problematic emissions such as benzene).
Another likely system for mobile transport in the near term is the petroleum hybrid, which is growing in use, followed by plug-in versions and, ultimately, if costs and other challenges are overcome, by the all-electric and, eventually, the fuel-cell–powered vehicle.
New Approaches, New Questions
With each of these new technologies, however, come potential health questions. For instance, while direct injection and related engine technologies do have benefits, HEI’s SCET members noted that they may also increase the emissions of ultrafine particulate matter. HEI Research and Review Committee members are now planning a review of the emissions of ultrafine particles, the extent of the population’s exposure to them, and the potential resulting health effects.
Similarly, ethanol raises questions about new kinds of emissions. Use of ethanol increases ethanol emissions, and its burning may result in increased emissions of acetaldehyde, which can contribute to the formation of smog and other effects in their own right. A number of emissions studies funded by EPA and the Department of Energy (DOE) to test new biofuels are under way. As a first step to assess this issue, HEI is organizing a workshop to bring the resulting data together to facilitate discussion and to target future research.
SCET members also noted that while electric vehicles drive clean, powering them still requires the generation of electricity. In the near term, a large proportion of electricity in some regions of the United States will continue to be produced by coal-fired power plants, potentially increasing emissions. The Committee identified, as well, lithium and other highly reactive metals in batteries as substances to be studied for their potential health effects arising from exposure throughout the battery life cycle — in other words, during manufacture, operation, maintenance, and disposal of vehicles powered by fuel cells and batteries. The Committee also noted potential questions about the health effects of the exposure of people to electric and magnetic fields while driving electric vehicles.
Hidden Costs. Sometimes the costs of energy are hard to see. Household electricity bills do not reflect all of the health and environmental costs of pollution from coal. Likewise, charges at the pump do not reflect all of the potential ecologic and other effects of producing the fuel, or of the consequences of events such as the 2010 Gulf of Mexico oil spill. A 2009 National Research Council study led by HEI Board member Jared Cohon estimated conservatively that in 2005 the use of fossil fuels resulted in $120 billion in health and other costs that were “hidden” (i.e., not included in energy prices). Just under half of those costs were attributed to transportation.
A HEALTHIER ENERGY FUTURE WORLDWIDE
While the developed world looks for new energy solutions to support its existing dependence on cars, trucks, and electricity, emerging Asian economies face these same challenges along with a rapidly growing demand for energy.
Much of that growth, which some estimates project will increase 150% by 2020, is coming from an escalating demand for vehicles.
Motor vehicle production has expanded in much of the world since the 1950s and in developing Asia more recently. Nowhere has the growth been greater than in China. China is now estimated to be the third largest producer of cars, trucks, and buses in the world and has become the largest national market for these vehicles.
A World Business Council on Sustainable Development report in 2004 projected that the number of vehicles on the road in Asia will double between 2000 and 2025. In China, projections predict a ninefold increase in demand for passenger cars alone and a fourfold increase in demand for light commercial vehicles between 2005 and 2025. India is not far behind, with a projected fivefold increase in demand for vehicles by 2025.
Air pollution, from vehicles and other sources, has also grown. In 2002, the World Health Organization estimated that over half a million people a year die prematurely in developing Asia because of air pollution. These conditions raise the need for high-quality investigations into the health effects of air pollution in Asia that can lead to informed decisions on new fuel and technology options in the near future.
At the forefront of this work is the Clean Air Initiative for Asian Cities (CAIAsia) program. CAIAsia is a partnership between government, industry, and nonprofit groups committed to promoting better air quality and livable cities by translating knowledge into policies and actions aimed at reducing air pollution and greenhouse gas emissions from transport and energy production. In July 2010, HEI Vice President Robert O’Keefe assumed the role of chair of this effort. “In this role,” said O’Keefe, “I hope to strengthen the link between science and air quality decisions.”
Smart Science
HEI’s Public Health and Air Pollution in Asia (PAPA) program is responding to this need by building scientific capacity and producing new high-quality scientific results. In 2010, the PAPA program published two benchmark publications on the latest science on air pollution and health in Asia. HEI’s Special Report 18, Outdoor Air Pollution and Health in the Developing Countries of Asia: A Comprehensive Review, provides an overview of the status of and trends in air pollution in Asia, a meta-analysis of 82 published Asian studies, and a critical review of Asian studies of the chronic effects of long-term air pollution exposure, as well as identification of important knowledge gaps for future studies. A second publication, Public Health and Air Pollution in Asia (PAPA): Coordinated Studies of Short-Term Exposure to Air Pollution and Daily Mortality in Four Cities (HEI Research Report 154), presents the results of four studies of the effects of air pollution on mortality in Shanghai, Wuhan, Bangkok, and Hong Kong, using a common protocol. That report also includes a combined analysis of the results from the four individual studies.
To help continue and enhance this vein of scientific inquiry, HEI received a $500,000 grant from the William and Flora Hewlett Foundation. The funding, to be provided over 2 years, supports research into the health effects of air pollution in Asia and Latin America. With that support, the PAPA program issued a Request for Applications and then selected and launched two new studies of air pollution and birth outcomes in China.
Informed Policies
HEI continues to participate in informing decisions made in China to develop its air quality standards and enhance its air quality management system. In May 2010, HEI President Daniel Greenbaum presented the latest PAPA results at a 3-day workshop in Beijing, at which adoption of a national Chinese air quality standard for fine particles (particulate matter less than or equal to 2.5 μm in aerodynamic diameter, or PM2.5) was being considered. He described how the data in HEI’s studies might help inform new ambient air quality standards. In addition, HEI’s worldwide work on improved technologies for diesel engines offered examples of how cleaner technologies could benefit health and limit the effects of some pollutants on climate.
In India, HEI helped inform steps to mitigate air pollution planned in preparation for the 2010 Commonwealth Games, held in Delhi in October 2010. The discussion drew on HEI studies of the Atlanta and Beijing Olympic Games to help compare the merits of different pollution reduction measures leading up to the Games and to determine which measures should be retained permanently. Local athletes and others were hoping to achieve a substantial reduction in particulate matter, a reduction in the number of days with high ozone levels, and an overall increase in the number of clean-air days. As of April 2010, levels of some pollutants exceeded the standards on 92% of the days monitored.
In recognition of the accelerating market growth in Asia, HEI is working actively to ensure that its science portfolio is relevant to Asian conditions when possible and that these results are available and communicated in an understandable and thoughtful way to meet the growing needs of Asian decision makers in industry and government.
Traffic-Related Pollution
HEI’s Special Report 17, published in January 2010, underscores the importance of understanding the health effects of traffic-related air pollutants. The report, which assessed more than 700 studies of traffic-related pollution and health, found the highest exposure zone to be up to 300 to 500 meters from major roads, which means many people are at risk of exposure to emissions. Although the report found that the data on many health outcomes are incomplete, it also found strong evidence for traffic-related air pollution exacerbating asthma in children.
ASSESSING HEALTH OUTCOMES OF AIR QUALITY ACTIONS
Protecting the public from the risks of exposure to air pollution begins with scientifically informed policies and regulations that aim to reduce pollutants and improve air quality.
But it doesn’t end there.
Once a new policy is in effect, a key next step is to determine if it is, indeed, reducing pollutants and improving air quality, and whether the resulting air quality changes also improve the health of the people breathing that air. Surprisingly, such health outcomes research is relatively new. HEI is already making progress in promoting this area of research by funding work that involves the active development of new data collection and research methodologies needed to advance this developing science.
Focus on Results
Since 2003, HEI has focused one arm of its scientific research on assessing the health outcomes of air quality actions. This effort stems from the fact that despite substantial investments in pollution controls over the past 40 years, considerable financial costs for ever-increasing controls will likely continue in the coming decades in response to science suggesting effects at lower and lower levels. As a result, HEI sponsors at the EPA and in industry have recognized the prudence of asking whether these regulations have yielded demonstrable improvements in public health.
This research will help inform future efforts to design policies that improve both the environment and public health. HEI has encouraged novel, creative, interdisciplinary approaches and recommended that the studies involve research teams with broad expertise, including in the areas of public health, epidemiology, statistics, and exposure. HEI also has encouraged partnerships with all levels of government.
Tallying the Results
Of the nine HEI-funded studies, which used a variety of approaches to evaluate diverse regulatory actions, nearly all have been completed. At the end of 2009, HEI hosted a workshop to examine the current state of these studies and to review and consider improvements to the methods used in these investigations.
Several studies found that changes in air quality in relation to an intervention such as a new regulation are sometimes difficult to show, especially if the regulation aimed to reduce traffic congestion, making air pollution reduction a tangential outcome.
For example, one HEI-funded study, led by Frank Kelly of King’s College London, examined the effects of a London effort to reduce traffic congestion during the day by charging vehicles a fee to enter the inner city between 7:00 a.m. and 6:00 p.m. on weekdays starting in 2003. Though policymakers expected air quality improvements in the long term, this was not the primary goal of the policy. The study did not find improvements in air quality that were large enough to allow analysis of the effects of air pollution changes on public health. The study, however, made substantial advances in developing methods for modeling air quality by contributing several approaches that can be used in future health outcomes studies.
Another HEI-funded study looking at air quality outcomes, led by Jennifer Peel of Colorado State University, focused on a short-term intervention to reduce traffic during the 1996 Olympic Games in Atlanta. Measures taken included developing “intelligent transportation systems” to move the many visitors to and from the Games, as well as a community effort to encourage vacations and provide means for telecommuting to ease the burden of regular local traffic. According to an earlier study in 2001, these efforts appeared to have reduced both ozone concentrations and acute care visits for pediatric asthma.
Jennifer Peel’s study expanded this previous work by evaluating wider time windows and a larger geographic area. She and her colleagues concluded that the decrease in ozone concentrations was a regional phenomenon and unlikely to be related to the traffic reduction efforts during the Olympics. She also found little or no evidence for reduced emergency room visits during the Games, although the HEI Review Committee pointed out that it would be difficult to find such evidence in a study covering an air quality action that lasted only a few weeks.
Making Improvements
These studies emphasize the importance of examining the full chain of events that might result from any kind of environmental intervention. For example, a study must ask first if an intervention actually reduced traffic. Then it must ask whether that reduction in traffic resulted in improved air quality. Then, finally, the study may examine whether any observed improvements in air quality actually resulted in health improvements.
After reviewing the results at the recent workshop, HEI and its advisers set a path for the future of this kind of health outcomes research. It involves a large number of detailed recommendations — especially to enhance studies of actions that take effect over long periods of time. The workshop participants also recommended four important “supports” for this work. Those include continuing the kind of retrospective epidemiologic studies funded in the first set of studies to estimate the health influences of air quality changes and also increasing the number of prospective efforts. HEI will also work with others to develop a national environmental health data warehouse for this kind of health outcomes research. In support of continued improvements in methods and approaches, HEI will encourage studies that help set realistic expectations for future investigations of complex health outcomes, such as cardiovascular disease. Finally, HEI will make efforts to close the loop between pre-regulation (i.e., baseline) and post-regulation science by anticipating upcoming actions and asking health outcomes questions earlier in the decision process.
Looking Ahead
Reducing air pollution to protect the public health has become increasingly challenging. Outdoor levels of key pollutants have declined, but epidemiologic studies continue to show adverse effects. To create cost-effective and focused air pollution control strategies, decision makers need clear, detailed data about how pollutants affect health. HEI is concentrating its efforts on determining, scientifically, if the projected benefits of current control measures are being realized, and if the costs of controls make sense given their effects on public health.
SCIENCE OF THE HIGHEST QUALITY
HEI has one primary goal: to produce unimpeachable, impartial, and trusted science.
The Science of Good Science
After seeking advice from sponsors and other interested parties, the HEI Research Committee — a group of independent experts from a variety of relevant scientific fields — determines HEI’s research priorities. The Committee then solicits and reviews applications from scientists who submit proposals for studies that address these priorities. Only studies that meet the highest standards for quality and relevance are selected. Throughout each study, HEI and its Research Committee maintain close contact with the selected investigators and ensure that the data collected are of the highest quality.
At the end of each study, HEI’s Review Committee — a separate committee of experts with the same range of expertise — receives a comprehensive report from the investigators. The Review Committee, which has no role in the review of applications or in the selection or conduct of projects, assesses the scientific quality of each study and evaluates its contribution to unresolved scientific and policy questions.
Minding the Gap
Through scientific research, HEI aims to fill important gaps in our understanding of the health effects of air pollutants. One specific gap HEI is addressing is in the understanding of the effects of exposure to low levels of ozone and other pollutants on the human cardiovascular system. Although responses to exposures to ozone at near ambient levels have been studied previously, most studies have focused on respiratory effects in healthy young people. HEI’s planned research, sought in a competitive Request for Applications issued in January 2010, focuses on the potential effects on the cardiovascular system of low-level exposure to ozone, in the presence and absence of other ambient pollutants, in older, more vulnerable people.
HEI’s separation of its research selection and its research evaluation maintains checks and balances, fosters impartiality, and ensures that the science it supports is of the highest quality. One peer review panel convened by EPA in 2010 to examine HEI’s work over the preceding 5 years commented: “Over the past 30 years, the independence, impartiality, and timeliness of HEI-supported research remain the key values of the organization.”
The Experts Behind Good Science
In addition to strong leadership, relevant scientific expertise earns HEI its reputation for quality science. That is especially true of the rigorous approach to biostatistics that HEI’s Committees apply to all studies. To that end, HEI recently welcomed two new well-recognized experts who specialize in biostatistics and study design to its Committees, which subject the designs of proposed and in-progress studies, as well as their final analyses, to careful scrutiny.
Often, the studies HEI selects involve complex environmental modeling and data collection to assess changes in air quality, as well as analysis of intricate biologic data to determine health effects. For instance, in population studies geared to investigating the effects of exposure to particulate matter and ozone, important issues will include whether exposure is being measured accurately, whether the right statistical methods are being applied, and whether all potential alternative explanations of effects (i.e., confounders) are considered.
These are just a small sampling of the kinds of questions that must be considered when designing studies that control for the many variables involved and that generate data powerful enough to draw strong conclusions.
To replace the expertise of individuals who had reached the end of their term limits, the Research and the Review Committees each added a new statistical expert this year. In June 2009, HEI’s Review Committee welcomed Lianne Sheppard of the University of Washington’s School of Public Health, Seattle. Sheppard, a widely published and rigorous biostatistician, specializes in epidemiologic studies of air pollution. In spring 2010, HEI’s Research Committee welcomed Richard Smith, another well-known statistician and the Director of the Statistical and Applied Mathematical Sciences Institute at the University of North Carolina–Chapel Hill.
Both Sheppard and Smith have research talents that align with the expertise required to meet the scientific challenges of HEI’s new initiatives, such as the novel and forward-looking health outcomes studies that evaluate the success of different regulatory interventions.
The Leaders of Good Science
This year, HEI recognized the outstanding service of Mark Utell (top), HEI’s Research Committee chair until spring 2010. HEI has made many scientific contributions and experienced many successes during Utell’s 10 years of leadership. A professor of medicine and environmental medicine at the University of Rochester, Utell will continue to stay involved with the oversight of HEI’s Advanced Collaborative Emissions Study (ACES) and its National Particle Component Toxicity (NPACT) studies.
To lead the Committee going forward, HEI conducted a national search and was pleased to welcome David Eaton (bottom) as its new Research Committee chair this spring. Eaton is director of the Center for Ecogenetics and Environmental Health at the University of Washington, Seattle, and his research focuses on toxicogenomics, the idea that some people are genetically more sensitive to chemical carcinogens than others. Eaton has chaired a number of important committees for the National Research Council and is a fellow of the American Association for the Advancement of Science. We are looking forward to Eaton’s leadership of this crucial committee, which is committed to guiding HEI’s research plans.
Journal Articles: 9 Displayed | Download in RIS Format
Other center views: | All 17 publications | 10 publications in selected types | All 9 journal articles |
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Carone M, Dominici F, Sheppard L. In Pursuit of Evidence in Air Pollution Epidemiology:The Role of Causally Driven Data Science. EPIDEMIOLOGY 2020;31(1):1-6. |
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Choirat C, Braun D, Kioumourtzoghlou M. Data Science in Environmental Health Research. ENVIRONMENTAL EPIDEMIOLOGY 2019;6(13):291-299. |
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Matthaios V, Lawrence J, Martins M, Ferguson S, Wolfson J, Harrison R, Kourtrakis P. Quantifying factors affecting contributions of Roadway exhaust and non-exhaust emissions to ambient PM10-2.5 and PM2.5-0.2 particles. SCIENCE OF THE TOTAL ENVRIONMENT 2022;835. |
R834677 (Final) R835872 (2020) |
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Meng Q, Hackfeld LC, Hodge RP, Walker VE. Comparison of mutagenicity of stereochemical forms of 1,2,3,4-diepoxybutane at HPRT and TK loci in human cells. Environmental and Molecular Mutagenesis 2003;41(36 Supplement):77. |
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Meng Q, Redetzke DL, Hackfeld LC, Hodge RP, Walker DM, Walker VE. Mutagenicity of stereochemical configurations of 1,2-epoxybutene and 1,2:3,4-diepoxybutane in human lymphoblastoid cells. Chemico-Biological Interactions 2007;166(1-3):207-218. |
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Mork D, Braun D, Zanobetti A. Time-lagged relationships between a decade of air pollution exposure and first hospitalization with Alzheimer's disease and related dementias. ENVIRONMENTAL INTERNATIONAL 2023;171(107694) |
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Papadogeorgou G, Kioumourtzoglou M, Braun D, Zanobetti A. Low Levels of Air Pollution and Health:Effect Estimates, Methodological Challenges, and Future Directions. CURRENT ENVIRONMENTAL HEALTH REPORTS 2019;6(3):105-115. |
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Shi L, Wu X, Danesh Yazdi M, Braun D, Abu Awad Y, Wei Y, Liu P, Di Q, Wang Y, Schwartz J, Dominici F, Kioumourtzoglou M-A, Zanobetti A. Long-term effects of PM2·5 on neurological disorders in the American Medicare population:a longitudinal cohort study. The Lancet Planetary Health 2020; 4(12):e557-e565. |
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Wu X, Nethery RC, Sabath MB, Braun D, Dominici F. Air pollution and COVID-19 mortality in the United States:Strengths and limitations of an ecological regression analysis. Science Advances 2020; 6(45) |
R834677 (Final) R835872 (2020) |
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Supplemental Keywords:
Emissions, air quality, diesel, health effects, carbon monoxide, ozone, nitrogen dioxide, particulate matterRelevant Websites:
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Progress and Final Reports:
Original Abstract Subprojects under this Center: (EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).
R834677C149 Development and Application of a Sensitive Method to Determine Concentrations of Acrolein and Other Carbonyls in Ambient Air
R834677C150 Mutagenicity of Stereochemical Configurations of 1,3-Butadiene Epoxy Metabolites in Human Cells
R834677C151 Biologic Effects of Inhaled Diesel Exhaust in Young and Old Mice: A Pilot Project
R834677C152 Evaluating Heterogeneity in Indoor and Outdoor Air Pollution Using Land-Use Regression and Constrained Factor Analysis
R834677C153 Improved Source Apportionment and Speciation of Low-Volume Particulate Matter Samples
R834677C155 The Impact of the Congestion Charging Scheme on Air Quality in London
R834677C156 Concentrations of Air Toxics in Motor Vehicle-Dominated Environments
R834677C158 Air Toxics Exposure from Vehicle Emissions at a U.S. Border Crossing: Buffalo Peace Bridge Study
R834677C159 Role of Neprilysin in Airway Inflammation Induced by Diesel Exhaust Emissions
R834677C160 Personal and Ambient Exposures to Air Toxics in Camden, New Jersey
R834677C162 Assessing the Impact of a Wood Stove Replacement Program on Air Quality and Children’s Health
R834677C163 The London Low Emission Zone Baseline Study
R834677C165 Effects of Controlled Exposure to Diesel Exhaust in Allergic Asthmatic Individuals
R834677C168 Evaluating the Effects of Title IV of the 1990 Clean Air Act Amendments on Air Quality
R834677C172 Potential Air Toxics Hot Spots in Truck Terminals and Cabs
R834677C173 Detection and Characterization of Nanoparticles from Motor Vehicles
R834677C174 Cardiorespiratory Biomarker Responses in Healthy Young Adults to Drastic Air Quality Changes Surrounding the 2008 Beijing Olympics
The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.