Publications

This report describes semiparametric methods for epidemiologic investigations of the short-term effects of air pollution on health, intended specifically to improve the reliability of point estimates and confidence intervals. Dr. James Robins of the Harvard School of Public Health and colleagues developed the new methods, used simulations to compare them with other methods, and applied them to a large epidemiologic data set from the National Morbidity, Mortality, and Air Pollution Study (NMMAPS) to assess their effectiveness. The report is accompanied by a short editorial to assist the reader in understanding this study and its contributions to epidemiologic methods for air pollution.

This report describes the results of a study of long-term effects of PM components in the American Cancer Society's Cancer Prevention Study II cohort; a time-series study of short-term effects of PM components on cardiovascular and other diseases in people living in 150 U.S. cities; and two toxicologic studies in animals exposed by inhalation to concentrated ambient particles, and in animals and human cells exposed to particles collected on filters from five different airsheds across the United States. This report, along with Research Report 178 (Vedal et al.), is one of HEI's National Particle Component Toxicity (NPACT) studies, which describe the most systematic multidisciplinary studies to date to investigate the health effects of PM components in humans and animal models at locations across the United States where the effects of PM sources and components may differ. The report includes a Commentary and a Synthesis by the NPACT Review Panel.

This report revisits an earlier study of the air pollution and health impacts of a coal ban in Dublin, Ireland, and then extends the analysis to coal bans in 11 additional Irish cities. Dr. Douglas W. Dockery of the Harvard School of Public Health and colleagues evaluated changes in black smoke and sulfur dioxide concentrations for the 5 years before and after the coal bans and examined how those changes related to mortality and hospitalization rates in the counties affected by the bans, as compared with other counties where coal bans were not implemented. They also included in their analysis other trends in health and social factors that were occurring at the same time.

This newsletter reports on an expert panel named to review diesel epidemiology studies, two HEI Asia workshops on the global health impact of air pollution, and a meeting of HEI's Research Committee and sponsors reviewing progress and priorities, as well as HEI in the news.

This report describes a study in which a nano aerosol mass spectrometer (NAMS) was used to study composition of nanoparticles in real time near a major roadway intersection. Dr. Murray V. Johnston of the University of Delaware, Newark, and colleagues conducted a field test in Wilmington, Delaware, to evaluate performance of the instrument in a real-world setting and to assess whether it could aid in identifying the major source contributions to nanoparticle spikes and background levels, including distinguishing diesel from gasoline vehicles.

Perspectives 3 is the third of a series produced by HEI to describe and interpret results from HEI and other research bearing on important and timely issues for a broad audience interested in environmental health. Perspectives 3 focuses on the health effects of ambient ultrafine particles (UFPs) and was developed under the guidance of a special HEI Review Panel. It examines the contribution of motor vehicles within the broader context of the multiple sources of ambient UFPs and explores the evidence from experimental studies in animals and in humans, as well as observational epidemiologic studies of people exposed to UFPs in the environment. It also identifies some of the broader lessons about both the specific health effects associated with exposure to UFPs and possible directions for future studies that could enhance our understanding of emissions, exposures, and effects of UFPs.

This report describes a study that analyzed the relationships between reductions in pollutants from power plants and fine particulate matter (PM_2.5) concentrations in the eastern United States between 1999 and 2005. Dr. Richard D. Morgenstern of Resources for the Future and colleagues used a novel data-driven source-receptor model to explore the statistical relationships between source emissions of sulfur dioxide (SO₂) and nitrogen oxides and monitored concentrations of PM_2.5. They performed various external comparisons of their models, and compared the reductions to an estimated counterfactual scenario in which no mandated reductions in SO₂ occurred.

This report describes the first-ever multicity study to estimate the effect of short-term exposures to particulate matter (PM₁₀) and to ozone on mortality in nine Latin American cities. Led by Dr. Isabelle Romieu in Mexico, in collaboration with Dr. Nelson Gouveia in Brazil and Dr. Luis Cifuentes in Chile, the researchers evaluated mortality from all causes and in different age groups, using a common analytic framework. They analyzed mortality in each city and the region as a whole, and explored two pollutant models in individual cities. They also used two meta-analytic statistical techniques to further analyze the effects from individual cities.

This report describes a study to explore the role that specific chemical constituents of particulate air pollution may have played in effects on daily mortality observed after the 1990 Hong Kong restriction on sulfur in fuels. The study was part of HEI's Outcomes Research program, which aims to assess the health impacts of actions taken to improve air quality. Dr. Chit-Ming Wong of the University of Hong Kong and his team also developed methods to estimate the impacts on life expectancy of the 1990 sulfur restriction.

This report describes a study to investigate the relationships among daily variations in air pollution in Ho Chi Minh City (HCMC), Vietnam, hospital admissions for acute lower respiratory infections in children under age 5, and poverty. The study was part of HEI's Public Health and Air Pollution in Asia (PAPA) program and is the first study of air quality and health to be performed in Vietnam. The team of investigators, led by Drs. Le Truong Giang, Long Ngo, and Sumi Mehta, collected daily pollutant data for PM₁₀, sulfur dioxide, nitrogen dioxide, and ozone at multiple locations throughout the city and obtained admissions data from the two pediatric hospitals in HCMC. They then performed statistical analysis on the data using Poisson time-series and case–crossover methods.