The reproductive toxicology of Great Lakes contaminants

The Great Lakes basin is characterized as a heavily populated and industrialized region in which a large number of environmental contaminants have been identified. Both the scientific community and the public have voiced concern that contaminants present in the Great Lakes may pose undue risk to human reproduction. Evidence from animal experiments, wildlife studies, and reports of occupational and accidental human exposures indicate that chemical contaminants can adversely affect reproduction. The purpose of this paper is to review the reproductive toxicity of some of the many contaminants known to be present in the Great Lakes. Since the number of chemicals present in the Great Lakes is far too great for each to be adequately reviewed here, discussion will be limited to those contaminants that have been identified in human serum, ovarian follicular fluid, and semen obtained from people residing in the Great Lakes region. It is concluded that a) the data at present is too limited to support the notion that reproduction, in the general population, has been impaired by exposure to chemicals present in the Great Lakes; b) the lack of data in some cases such as for hexachloroethane and 1,2,4-trichlobenzene does provide reason for concern and underscores the need for further research in this area; and c) the potential for a number of the compounds, including polychlorinated biphenyls (PCBs) and 1,1,1-trichloro-2,2-bis(p-chlorophenyl) ethane (DDT), to disrupt endocrine functions suggests that additive or synergistic effects of these compounds may already be causing adverse effects on reproduction in sensitive individuals, which needs to be explored.