Evaluation of risks from urban air pollutants in the southeast Chicago area

Region V of the U.S. Environmental Protection Agency has conducted a comprehensive study of cancer risks from urban exposure to air pollutants in the Southeast Chicago area. This study estimated emissions of a list of 30 air carcinogens from a broad range of nontraditional, as well as traditional, source types. Using dispersion modeling and applying the appropriate unit risk factors and population data, this study estimated the risks at each receptor location and the total number of cancer cases attributable to air pollution in the area. This analysis estimated that current concentrations would cause 77 cases of cancer over the next 70 years, an average risk of 2.0 X 10(-4). Contributions from different source types and different pollutants were estimated. The total contribution from nontraditional source types was less than 0.3 percent. Although these estimates are highly uncertain, the study does suggest the nature and general magnitude of cancer risks from air pollution in the urban area studied.