Food-derived mutagens and carcinogens.

TLDR

Cooked food contains various mutagenic heterocyclic amines. Heterocyclic amines likely cause cancer by forming guanine adducts. Rodent studies show that dietary heterocyclic amines (0.01–0.08%) are carcinogenic, inducing liver and other organ cancers, with the most abundant amine causing colon, mammary, and lymphomas but not hepatomas; in monkeys, a related amine induced liver cancer; humans are continuously exposed to low levels, which alone may be insufficient to cause cancer, yet a linear dose–adduct relationship indicates that even low doses could contribute to human cancer when combined with other mutagens and tumor promoters.

Abstract

Cooked food contains a variety of mutagenic heterocyclic amines. All the mutagenic heterocyclic amines tested were carcinogenic in rodents when given in the diet at 0.01-0.08%. Most of them induced cancer in the liver and in other organs. It is noteworthy that the most abundant heterocyclic amine in cooked food, 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine, produced colon and mammary carcinomas in rats and lymphomas in mice but no hepatomas in either. 2-Amino-3-methylimidazo[4,5-f]quinoline induced liver cancer in monkeys. Formation of adducts with guanine by heterocyclic amines is presumably involved in their carcinogenesis. Quantification of heterocyclic amines in cooked foods and in human urine indicated that humans are continuously exposed to low levels of them in the diet. These low levels of heterocyclic amines are probably insufficient to produce human cancers by themselves. However, a linear relationship between DNA adduct levels and a wide range of doses of a heterocyclic amine was demonstrated in animals. It suggests that even very low doses of heterocyclic amines form DNA adducts and may be implicated in the development of human cancer under conditions in which many other mutagens-carcinogens, tumor promoters, and factors stimulating cancer progression exist.