A perspective on the risk assessment process for endocrine-disruptive effects on wildlife and human health.

The topic of EDCs presents significant issues to the risk assessment process. In Table I, we have summarized many of the issues raised above. We have a working definition of an EDC, that provides a starting point for considering what chemicals are of concern. We also have an understanding of the important biological endpoints. Significantly, there are indications that large scale impacts might be occurring in both human and wildlife populations. Should these effects be confirmed and the causative agents identified, we will face difficult risk management decisions to minimize or mitigate the risks. Our present knowledge base, however, suggests that the traditional approach to assessing both noncancer and cancer endpoints will be suitable for toxicity mediated through disruption of endocrine systems, although there is controversy here as well. The fact that many EDCs share a common MOA should, in fact, assist in developing more scientifically defensible risk assessments, given that we must often extrapolate across doses and species in the absence of a mechanistic basis for noncancer effects. As more research focuses on the key uncertainties, we should acquire a better vision of the relative risks that EDCs pose to humans and wildlife.