Understanding the Role of Traffic Emissions on Near-Road Air Quality and Population Exposures

RICHARD BALDAUF (1), Gorge Bowker (2), Laurie Brixey (3), Fu-Lin Chen (2), Seung-Hyun Cho (1,4), Dave Davies (4), Ian Gilmour(4), Brian Gullett (1), Gayle Hagler (1), Mike Hays (1), David Heist(2), Jason Herrington (1), Vlad Isakov(2), Andrey Khlystov (5), Sue Kimbrough(1), John Kinsey(1), Todd Krantz(4), Jeff Lantz(2), Tom Long(1), John McGee(4), David Olson(2), Steve Perry(2), Patricia Rowley(1), Robert Seila(2), Richard Shores(1), Richard Snow (6), Eben Thoma(1), Alan Vette(2), Nealson Watkins(7), Jason Weinstein(2), Donald Whitaker(2), Ronald Williams(2)

(1) U.S. Environmental Protection Agency, Office of Research and Development, National Risk Management Research Laboratory, (2) U.S. Environmental Protection Agency, Office of Research and Development, National Exposure Research Laboratory, (3) Alion Inc., (4) U.S. Environmental Protection Agency, Office of Research and Development, National Health and Environmental Effects Research Laboratory, (5) Duke University, College of Engineering, (6) Arcadis Inc., (7) U.S. Environmental Protection Agency, Office of Air Quality Planning and Standards

     Abstract Number: 113
     Last modified: November 4, 2009

Abstract
In recent years, a growing number of health studies have identified increased risks of adverse health effects for populations spending significant time near large roads. Emission inventories reveal that mobile sources significantly contribute to local and national concentrations of a number of air pollutants. Air quality monitoring and personal exposure studies have measured elevated concentrations and exposures to pollutants emitted directly by motor vehicles, adding to the public health concern for adverse health effects resulting from exposures to motor vehicle emissions.

The EPA has conducted a research program to characterize traffic impacts on near-road air pollution and its impacts on personal exposures and human health. This research has included direct measurements of traffic activity, meteorology, and air pollutant concentrations; measurements of personal exposure for near-road populations, wind tunnel assessments, and computational fluid dynamics modeling. In addition, EPA has conducted research on impacts of roadway design on the dispersion of pollutants near roads, in order to identify potentially effective mitigation strategies. The measurement studies show how traffic intensity and meteorological conditions impact near-road air pollutant concentrations, including effects on coarse, fine, and ultrafine particulate matter. In addition, measurement data, wind tunnel testing, and computational fluid dynamic modeling demonstrate that air pollutant impacts near roads may be mitigated by infrastructure design options such as the roadway configuration and presence of roadside structures. These results have influenced the improvement of air quality and exposure models, and supported the design of monitoring networks for regulatory and research near-road monitoring needs.

This presentation will synthesize the results of these efforts to improve understanding of the role of traffic emissions on air quality, exposures, and ultimately public health.