a family of highly toxic chemical compounds consisting of two benzene rings in which chlorine takes the place of two or more hydrogen atoms: known to cause skin diseases and suspected of causing birth defects and cancer.
Polychlorinated biphenyl; any of a family of industrial compounds produced by chlorination of biphenyl, noted primarily as an environmental pollutant that accumulates in animal tissue with resultant pathogenic and teratogenic effects.
Short for polychlorinated biphenyl. Any of a family of very stable industrial compounds used as lubricants, heat-transfer fluids, and plasticizers. The manufacture and use of PCBs has been restricted since the 1970s because they are very harmful to the environment, being especially deadly to fish and invertebrates, and stay in the food chain for many years.