Human health, the Great Lakes, and environmental pollution: a 1994 perspective.

The Great Lakes constitute the largest body of surface freshwater on earth and are one of the planet's most valuable natural resources. Home to roughly 36 million people, the Great Lakes basin is a major industrial and agricultural region of North America. The Canadian portion of the basin contains one-third of the Canadian population and half of all the manufacturing activity in Canada. The health and integrity of the Great Lakes ecosystem has been the subject of much public and scientific interest and debate over the past 25 years. In the early 1970s, scientists, provincial and state governments, and Great Lakes communities began to express serious concerns about the integrity of the Great Lakes ecosystem and the potential harmful effects of toxic chemicals present in the Great Lakes. By the mid-1980s, over 800 distinct chemical substances from a variety of industrial, agricultural and municipal sources had been identified in the Great Lakes basin, ofwhich only 40 to 50% were well known (1). Of