They can disturb behavior and reproduction in birds, fish, and mammals. PCBs have contributed to population declines and health problems in fish eating mammals in polluted areas, including the beluga in Canada's St. Lawrence River estuary. In humans, PCBs can inhibit development of the nervous system and liver enzymes, and cause cancer and birth defects. The radar sites built by the U.S. military were supposed to warn of a deadly threat coming over the North Pole from the former Soviet Union. The Cold War is over and the new threat comes from the radioactive pollution that remains at these radar sites.
Resolution Island is one such site.
The island off the southern tip of Baffin Island and south of about 500 kilometers south of the Arctic Circle was used by the U.S. Air Force from 1953 to 1972. Soil on the island became contaminated from PCBs that leaked out of old electrical equipment. The contamination is particularly serious for the region's Inuit population who still hunt for food. Scientific evidence shows levels of PCBs in the blood of some Inuit women are higher than Health Canada guidelines. Levels of other persistent organic pollutants in breast milk have been found up to nine times higher than in women who live in southern Canada.