Analysis of the Impacts of Control Programs on Motor Vehicle Toxics Emissions and Exposure in Urban Areas and Nationwide: Volume l.

摘要

Under Work Assignment 1-06 of U.S. Environmental Protection Agency (EPA) contract #68-C7-0051, Sierra Research, Inc. (Sierra), in conjunction with subcontractor Radian International Corporation/Eastern Research Group (Radian/ERG), has performed a number of tasks related to the evaluation of motor vehicle air toxics emissions, exposure, and risk assessment. This study expanded upon a previous analysis of motor vehicle air toxics performed by Sierra, Radian, and Energy and Environmental Analysis (EEA) in 19981* to include additional control scenarios and modeled areas. As described below, emissions and exposure estimates were prepared for the following air toxics: benzene, acetaldehyde, formaldehyde, 1,3-butadiene, MTBE, and Diesel particulate. The analysis was performed for ten selected urban areas in the U.S. under a variety of control scenarios. An additional 16 regional areas were evaluated in order to provide a broad range of fuel parameters, temperature regimes, and I/M programs that were needed for national estimates of toxics emissions and exposure. Estimates were prepared for calendar years 1990, 1996, 2007, and 2020. Although risk estimates were not prepared as part of this study, the modeling framework to perform those