The role of laboratory animal studies in estimating carcinogenic risks for man.

The extent to which biological processes predict those in humans is discussed and illustrated by analysis of data presented in the first 16 volumes of the IARC Monograph series. Other examples are given to show that if there is sufficient evidence that a chemical is carcinogenic in appropriate animal test systems it must be treated as if it were carcinogenic in humans. A quantitative correlation between data in animals and in humans is more difficult to establish, although there is tentative evidence that such a relationship exists. Society should attempt to keep 'inevitable' exposures to carcinogens to a minimum; social need should be balanced against social risk. Biomedical research can help to estimate this role.