Research Reports

This report provides the first systematic look at the health effects of exposures to emissions from a new-technology heavy-duty diesel engine. Included in this report are results obtained in rats and mice exposed for 1 and 3 months (and some results in rats at 12 months) to exhaust from a 2007-compliant diesel engine with aftertreatment to reduce particulate matter concentrations. Part 1 describes the core inhalation study by Drs. Jake McDonald and Joe Mauderly of the Lovelace Respiratory Research Institute, with results on general organ toxicity, lung histopathology, pulmonary function, and markers of inflammation and oxidative stress in blood and lung lavage fluid. Parts 2 and 3 describe studies by Drs. Jeffrey Bemis of Litron Laboratories and Lance Hallberg of the University of Texas Medical Branch, respectively, assessing genotoxic endpoints in the exposed rodents. Part 4 describes a study of vascular markers by Daniel Conklin of the University of Louisville. The Preface to this report contains background information about the planning and designing of the study, including decisions regarding the diesel exhaust dilutions and the choice of rodent strains.

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.

This report describes a study evaluating the effects of exposure to diesel exhaust (DE) and nitrogen dioxide (NO₂) on the lower airways and blood of allergic asthmatic participants. The study by Dr. Riedl and colleagues was funded as part of HEI's research program looking at diesel exhaust and other particle exposures and allergic response. The participants were exposed in random order to 100 µg/m³ diesel exhaust or 0.35 ppm nitrogen dioxide for 2 hours, with or without an allergen inhalation challenge. The investigators measured multiple physiologic and pulmonary function endpoints, including specific airway resistance, oxygen saturation, bronchial reactivity, and inflammatory and immunologic endpoints.

This report describes a study evaluating the feasibility of studying potential changes in air quality and health associated with the London Low Emission Zone (LEZ), which went into effect in 2008 and restricts entry of older, more polluting vehicles into Greater London. Based on their earlier study of London's Congestion Charging Scheme, Dr. Kelly and colleagues conducted emissions and exposure modeling to estimate the projected effects of LEZ implementation. They also assessed the feasibility of using medical records from private practices to evaluate the relationships between exposure to traffic and indicators of respiratory and cardiovascular disease.

This report describes a study that tested whether emissions from traffic caused an air toxics "hot spot" in a neighborhood in Buffalo, New York. Dr. Spengler and colleagues hypothesized that vehicle-related emissions from heavy traffic at the Peace Bridge in Buffalo, one of the nation's busiest border crossings and a potential air pollution hot spot, would result in elevated downwind levels of mobile-source air toxics (MSATs) and other traffic-related pollutants. The investigators measured levels of a large number of MSATs as well as six criteria pollutants using both fixed-site and mobile monitoring in order to examine the relation between traffic at the bridge and the spatial distribution of ambient pollutant concentrations at the bridge and in an adjacent neighborhood.

This report describes a study that was funded under HEI's research program aimed at measuring the possible health impacts associated with actions taken to improve air quality (health outcomes research). Dr. Kelly and colleagues used a multifaceted approach to exploring the impact of the Congestion Charging Scheme on air quality, which involved a variety of emissions and exposure modeling techniques, analysis of air monitoring data, and a newly developed assay for the oxidative potential of particulate matter collected on filters at urban backgrounds and roadside monitors.