Publications

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.

Contents: Effects of Exposure to Diesel Exhaust Particles in Persons with Asthma and Allergy; Workshop Brings Experts Together: Atmospheric Chemists and Health Effects Scientists Meet at HEI to Discuss Common Goals; Symposium Sheds Light on Air Toxics Hot Spots; Wood Stove Changeout Program Brings Some Improvements in Health, Air Quality; Three New HEI Studies Launched: Ozone Exposure and Inflammatory Cells / PM Exposure and Heart Rhythm / Impact of Exposure in Early Life; ACES Reaches Important Milestones; New Investigator

This report describes a study that evaluated whether exposure to fine or nano-titanium dioxide (TiO₂) particles may affect cardiovascular endpoints, in particular endothelium-dependent vascular dilation. Dr. Nurkiewicz and colleagues exposed rats via inhalation to 0.5 to 20 mg/m³ TiO₂ for up to 12 hours and evaluated them for vascular dilation and for markers of oxidative stress, coagulation, and inflammation. This study was funded under the Walter A. Rosenblith New Investigator Award.   

This report describes a study that tested whether an air toxics "hot spot" existed in Camden, NJ. Dr. Lioy and colleagues evaluated ambient and personal exposures of nonsmoking residents to PM_2.5, VOCs, aldehydes, and PAHs in two neighborhoods in Camden, NJ, one of which was hypothesized to be a regional air toxics "hot spot." The investigators compared concentrations of air pollutants in the two neighborhoods with each other and then with concentrations at other locations in the United States. They also assessed the effects of seasonality, contributions from mobile sources, and spatial variability.

This report evaluates airway inflammatory responses and expression of the enzyme neprilysin in response to diesel exhaust particle exposure. Dr. Wong and colleagues hypothesized that components of diesel exhaust decrease neprilysin levels in airways, leading to airway function disorders and heightened responses to diesel exhaust. They exposed normal mice, mice genetically deficient in neprilysin, human subjects, and human airway epithelial cells to diesel exhaust particles and measured airway inflammation, neprilysin expression, and any unique responses in neprilysin-deficient mice.

This report contains studies in Chennai and Delhi led by Dr. Kalpana Balakrishnan and Dr. Uma Rajarathnam, respectively. These time-series studies of air pollution and mortality in India were funded under HEI's PAPA Program to provide information to inform regulatory and other decisions that would be relevant to local populations, with the added goal of supporting scientific capacity building in the region.

This report describes research funded under HEI's Air Toxics Hot Spot program. Dr. Eric Fujita and colleagues characterized concentrations of mobile-source air toxics (MSATs) and other pollutants in potential Los Angeles County pollution hot spots, including on urban highways with a varying mix of gasoline- and diesel-powered traffic and sites at various distances from the highways and close to other roads.

This report explores how land-use regression and source-apportionment techniques can be used to characterize individual-level exposure to both indoor and outdoor air pollution sources. Dr. Levy and colleagues utilized health and air monitoring data from an ongoing prospective cohort study on childhood asthma in Boston, Massachusetts to model variability in outdoor and indoor residential air pollution, identify potential sources, and evaluate the effectiveness of various indoor exposure surrogates for predicting childhood asthma development.

This report describes the first set of coordinated time-series studies ever undertaken in Asian cities: four time-series studies of the health effects of air pollution in Bangkok, Hong Kong, Shanghai, and Wuhan. These studies were intended to help bridge the gaps between studies conducted in different locations around the globe.

Communication 15, Proceedings of an HEI Workshop on Further Research to Assess the Health Impacts of Actions Taken to Improve Air Quality, summarizes the findings of a workshop held in December 2009 that reviewed the current state of research to evaluate the impact of air quality interventions (also known as accountability or air quality outcomes research).

This report describes a study by Dr. Thomas Cahill and colleagues to create and evaluate a new method to measure acrolein and other volatile carbonyls present at low concentrations in ambient air. Acrolein is an important aldehyde that is very difficult to measure accurately, so developing better methods for measuring levels and exposure is critical to better risk assessment for the chemical. The investigators developed a sampler that traps acrolein using sodium bisulfite in an aqueous medium.