Evaluation and classification of the potential carcinogenicity of organic air pollutants∗

This study was supported by the National Cancer Institute, Contract No. NO1‐CP‐95607

Abstract

Data on the carcinogenicity and Ames Salmonella test muta‐genicity were compiled for 671 organic chemicals reported to be potential air pollutants. Development of the data base entailed an evaluation of published reports of carcinogenicity and mutagenicity test results available in the open literature. Criteria were established for classifying the chemicals as recognized carcinogens, suspected carcinogens, tumor promoters or cocarcinogens, and mutagens or suspected mutagens. Confirmation of chemicals as ambient air pollutants was attempted only for the chemicals classified into a category of potential carcinogenicity other than unknown. Primary and secondary literature sources were searched for the reported detection of the chemicals as ambient air pollutants. This work resulted in the classification of 77 air pollutants as potential human carcinogens, as demonstrated by the categorization of 25 air pollutants as recognized carcinogens, 20 air pollutants as suspected carcinogens, 15 air pollutants as tumor promoters/cocarcinogens, and 50 air pollutants as mutagens or suspected mutagens. For 17 of the 50 air pollutants classified as mutagens or suspected mutagens, no adequate positive carcino‐genicity data were found. No evidence of mutagenicity determined by the Ames test was found for seven of the 25 recognized carcinogens or for nine of the 20 suspected carcinogens.

Notes

This study was supported by the National Cancer Institute, Contract No. NO1‐CP‐95607

Reprints may be obtained from C. T. Helmes and also from Dr. H. F. Kraybill, Scientific Coordinator for the Office of Environmental Cancer, Division of Cancer Cause and Prevention, National Cancer Institute, Landow Building, Room C337, 7910 Woodmont Avenue, Bethesda, Maryland 20205