Health risks of heterocyclic amines.

Common cooking procedures such as broiling, frying, barbecuing (flame-grilling), heat processing and pyrolysis of protein-rich foods induce the formation of potent mutagenic and carcinogenic heterocyclic amines. These same compounds produce tumors at multiple organ sites in both mice and rats. One example of these induced tumors has also been seen in nonhuman primates. Risk assessment for the human population consuming these compounds requires the integration of knowledge of dosimetry, metabolism, carcinogenic potency, and epidemiology. When this integration is done in even a preliminary way as is done here, the range of risk for an individual from these compounds is enormous. Exposure contributes a range of 200-fold or more and metabolism and DNA repair differences among individuals could easily be an additional 10-fold between individuals. This indicates that differences in human cancer risk for heterocyclic amines could range more than a thousandfold between individuals based on exposure and genetic susceptibility.