The Great Lakes: a Historical Overview

The Great Lakes are collectively the largest inland body of freshwater on this planet. For more than two hundred years, the Great Lakes basin has been used as a resource for industry, agriculture, shipping, and recreation. The physical characteristics of the basin and the long retention time of chemicals in the lakes combine to make this huge freshwater resource a repository for chemical by-products of these activities. Many of the more than one thousand chemicals detected in the waters, sediment, or biota of the Great Lakes have known toxic effects. This overview will identify the 11 most persistent toxic chemicals known as "critical" Great Lakes pollutants. It also will describe some of the adverse health effects that have been observed in fish and other wildlife because of exposure to these pollutants. Finally. it will discuss some of the early human health studies that 1) have demonstrated a correlation between increased body burdens and fish consumption, and 2) suggest an association between consumption of contaminated Great Lakes fish and adverse human health effects.