A comprehensive literature search identified more than 125 high-volume chemicals having the potential of becoming airborne carcinogenic pollutants. Based on carcinogenicity and mutagenicity data, the pollutants were divided into three categories: probable carcinogens, possible carcinogens, and probable noncarcinogens. Additional data were collected for the possible and probable carcinogens including their annual production, emissions, atmospheric persistence, and relative mutagenic and carcinogenic potencies. The pollutants were then ranked on the basis of a calculated equivalent weight of benzo(a) pyrene emitted per year after 24 hours in the atmosphere. From the top portions of these two lists, 20 compounds, representing various chemical classes, were chosen for future analysis. A state-of-the-art review of the effect of cofactors on the carcinogenicity of chemicals was also completed. To locate optimum sampling sites in cities of interest, a series of carcinogen isopleths was generated. Using information such as the locations of stationary sources of carcinogenic pollutants, normalized wind direction and speed, and the height, temperature, and rate of flow of the sources, the probable locations of maximum carcinogenic pollution concentration were computed.

Contract no. 68-02-2773.