Polychlorinated Biphenyls (PCBs)

Also known as: Aroclor, Chlorinated Biphenyls, Kaneclor
Chemical reference number (CAS): 1336-36-3

PCBs are a group of 209 different compounds. PCBs are manufactured substances and have no smell. They are yellow, oily liquids that don't burn easily. There are no natural sources of PCBs.

Companies in the United States first made PCBs in 1929. They’'ve been used as coolants in electrical equipment, in metal-cutting oils, in microscope lens oils, and in inks, dyes, and carbonless copy paper.

In 1977, the U.S. Environmental Protection Agency (EPA) banned the use of PCBs. The EPA was concerned about the harmful effects of PCBs. For example, PCBs can accumulate in the environment. PCBs may be present in old fluorescent light fixtures and parts of appliances made before 1978.

PCBs break down very slowly and can be carried long distances in the air, in rivers, lakes and oceans. PCBs can build up over time in the fat of people and animals. Recent studies found that most people have traces of PCBs in their body fat. PCBs can accumulate in the food chain. For example, fish can have PCB levels in their fatty tissues that are much higher than in the surrounding water.

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Last Revised: March 24, 2016