Lexikon
polychlorinated biphenyls (PCBs) are a class of chlorinated organic compounds, with 1-10 chlorine atoms bound to the biphenyl skeleton, which is the condensate of two benzene rings. The general chemical formula of PCBs is: C12H10-xClx.
PCBs were used as dielectric fluids in transformers and capacitors, coolants, lubricants, stabilizing additives in flexible PVC coatings of electrical wiring and electronic components, they were used as pesticide extenders, flame retardants, hydraulic fluids, adhesives, anti-dust agents, coating of copy papers, etc.
PCB production was banned in the 1970s due to the high toxicity, mutagenicity and reprotoxicity. They are able to accumulate in the food chain. They are classified as POPs, Persistent organic pollutants.