Published by the Journal of the Air & Waste Management Association, April 2009, by Arlene Rosenbaum of ICF International, co-authored with the U.S. Environmental Protection Agency. Population-based human exposure models predict the distribution of personal exposures to pollutants of outdoor origin using a variety of inputs, including air pollution concentrations; human activity patterns, such as the amount of time spent outdoors versus indoors, commuting, walking, and indoors at home; microenvironmental infiltration rates; and pollutant removal rates in indoor environments.
The results of our study indicate that there is a strong spatial gradient in the predicted mean exposure concentrations near roadways and industrial facilities that can vary by almost a factor of two across the urban area studied.