Estimation of risks due to environmental carcinogenesis

Several Federal agencies share responsibility for enforcing laws designed to control human exposures to carcinogens. This enforcement activity often has immense effects on other factors of our environment. Absolute safety is not possible, but increased protection is obtainable. Improvements are urgently needed in our ability not only to detect but also to quantify relative risk. Resources should be directed for maximum overall effect. Relative risk must be quantified if we are to reasonably compare risk and benefit. Examples of the inexactness of current toxicological, epidemiological, and mathematical models for estimating risk due to exposures to DDT, aflatoxinb1, DES, and benzidine are presented. The impact of different laws and regulations applicable to the control of these agents is compared. Reference is made to major programs in toxicological methods for risk estimation.