United States mutagenicity testing

Epidemiologic studies in Japan indicate an increased risk of stomach cancer owing to consumption of broiled fish and meats (116). In the United States, stomach cancer incidence has steadily declined since the 1940s, whereas consumption of broiled food has increased (108). In addition, the average human intake of PAHs is only 0.002 of that required to produce cancer in half of animals fed. Test results are often contradictory (117) and many components of food, such as vitamin A, unsaturated fatty acids, thiols, nitrites, and even saUva itself, tend to inhibit the mutagenic activity of PAHs (118—120). Therefore, the significance of PAHs in the human diet remains unknown (121,109). 

DAB was genotoxic in the comet assay inducing DNA damage in the stomach, colon liver, bladder, lung, and bone marrow. It is also mutagenic to Salmonella in the Ames test. Because of its demonstrated carcinogenicity in animals, human exposure to DAB by any route should be avoided. In recent years, this compound has been used only in laboratories as a model of tumorigenic activity in animals. It is not produced commercially in the United States and is of little occupational health importance. 

Ames, B.N., Lee, F.D. and Durston, W.E. (1973) An improved bacterial test system for the detection and classification of mutagens and carcinogens. Proceeding of the National Academy of Sciences of the United States of America, 70, 782-786. 

In research, benzo(a)pyrene (BP) is used extensively as a positive control in a variety of laboratory mutagenicity and carcinogenicity short-term tests. It is not produced commercially in the United States. 

McCann J, Choi E, Yamasaki E, and Ames BN (1975) Detection of carcinogens as mutagens in the Salmonellal microsome test Assay of 300 chemicals. Proceedings of the National Academy of Sciences of the United States of America IT. 5135-5139. 

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