Carcinogenic Impurities in Food and Color Additives—An Analysis of Presumptive Risk Levels

Abstract

In April 1982, the Food and Drug Administration implemented a new policy (originally called the Carcinogenic Constituents Policy) under which it began issuing food and color additive regulations permitting the use of substances which (although noncarcinogenic themselves) may contain carcinogenic impurities. This policy is based upon the premise that such additives are not subject to prohibition under the Delaney Clause. Rather, their use can be considered safe as long as the upper-bound risk posed by exposure to the carcinogenic impurities is sufficiently low, as determined by a conservative carcinogen risk assessment procedure. During the seven years that the policy has been in effect, the FDA has issued over 50 regulations for uses of food and color additives which are known to contain carcinogenic impurities. This paper analyzes these data on the carcinogens of concern to see how the upper-bound risks in all cases vary simultaneously as a function of human exposure and carcinogen potency. Both potency and human exposure data are arrayed on a two-dimensional logarithmic coordinate system to explore the consequences of this novel policy.