Michigan's Kalamazoo River is polluted by polychlorinated biphenyls (PCBs), highly toxic chemicals banned in the 1970s.

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Polychlorinated biphenyls, (PCBs), chlorofluorocarbons (CFCs) and DDT are also organochlorine compounds which, although banned or discredited, are still evident in the environment.

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Untreated sewage and the 1.3 million pounds of polychlorinated biphenyls that General Electric dumped in the Hudson River turned the harbor into a cesspool.

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There was another class of hazardous chemical present: polychlorinated biphenyls (PCBs).

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Worse still, some of those fish are full of polychlorinated biphenyls (PCBs), which at worst, cause cancer and at best wreck humans' immune, reproductive, nervous and endocrine systems.

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Stripers there happen to be chock full of polychlorinated biphenyls (PCBs), which at worst, cause cancer in humans and at best wreck immune, reproductive, nervous and endocrine systems.

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Its sin: legally dumping 1.3 million pounds of polychlorinated biphenyls into the Hudson River over several decades, until these chemicals were banned in 1977, then dragging its feet on the cleanup.

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