Fish-eating birds population effects

PCBs have been implicated in the decline of certain populations of fish-eating birds, for example, in the Great Lakes of North America. Although their use is now banned in most countries and very little is released into the environment as a consequence of human activity, considerable quantities remain in sinks (e.g., contaminated sediments and landfill sites), from which they are slowly redistributed to other compartments of the environment. There continues to be evidence that PCB residues are still having environmental effects, for example, on birds and fish. 

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