HETEROCYCLIC AMINES FORMED BY COOKING FOOD - COMPARISON OF BIOASSAY RESULTS WITH OTHER CHEMICALS IN THE CARCINOGENIC POTENCY DATABASE

Results in the Carcinogenic Potency Database (CPDB) on 11 mutagenic he terocyclic amines (HA) tested for carcinogenicity in rats, mice and cy nomolgus monkeys are compared to results for other chemicals. An analy sis of strength of evidence of carcinogenicity for HA vs. other mutage nic carcinogens and vs. all rodent carcinogens, indicates strong carci nogenicity of HA in terms of positivity rates and multiplicity of targ et sites. The liver is the most frequent target site in each species. Despite several target sites in each species, concordance in target si tes between rats and mice is restricted to the liver for each HA excep t one. In cynomolgus monkeys, liver tumors have been induced rapidly b y 2-amino-3-methylimidazo[4,5-f]quinoline (IQ). Human exposures to HA in cooked animal foods are small, in the low ppb range. A comparison o f possible carcinogenic hazards from a variety of exposures to rodent carcinogens in the American diet is presented, using an index (Human E xposure/Rodent Potency, HERP) that relates human exposure to carcinoge nic potency in rodents. Results indicate that there is a large backgro und of exposures to naturally occurring rodent carcinogens in typical portions of common foods, and that possible hazards from HA rank below those of most natural pesticides and products of cooking or food prep aration; synthetic pesticide residues also rank low.