A COMPARISON OF WATER-QUALITY CRITERIA FOR THE GREAT-LAKES BASED ON HUMAN AND WILDLIFE HEALTH

Water-quality criteria (WQC) can be derived in several ways. The usual techniques involve hazard and risk assessment procedures. For non-per sistent, non-biomagnified compounds and elements, WQC are experimental ly derived from their acute and chronic toxicity to aquatic organisms. For those persistent chlorinated hydrocarbons (PCHs) that are bioaccu mulated and biomagnified, these traditional techniques have not been e ffective, partly because effects higher in the food web were not consi dered. Polychlorinated biphenyls (PCBs) are the bioaccumulative synthe tic chemicals of primary toxicological significance to the Great Lakes biota which have caused widespread injury to wildlife. In the Laurent ian Great Lakes, the primary emphasis of hazard assessments has been o n the potential for adverse effects in humans who eat fish. The primar y regulatory endpoint of traditional hazard and risk assessments under lying current WQC are the probabilities of additional cancers occurrin g in the human population. The analysis presented here indicates that this is not adequate to restore sensitive wildlife species that are hi ghly exposed to PCBs, especially those that have suffered serious popu lation declines. Because WQC are legal instruments, the methods of der iving WQC have large implications for remediation, litigation, and dam age assessments. Here WQC are derived for six species based on the res ponses of wildlife in the field or produced by feeding fish to surroga te species, rather than projecting a potential of increased cancer rat es in humans. If the most sensitive wildlife species are restored and protected for very sensitive reproductive endpoints, then all componen ts of the ecosystem, including human health, should be more adequately protected The management of Great Lakes wildlife requires an understa nding of the injury and causal relationships to persistent toxic subst ances.