Coplanar PCBs sources

Tanabe, S., N. Kannan, A. Subramanian, S. Watanabe, and R. Tatsukawa. 1987. Highly toxic coplanar PCBs occurrence, source, persistency and toxic implications to wildlife and humans. Environ. Pollut. 47 147-163. 

In Japan, under the Dioxins Law, PCDDs, PCDFs and coplanar PCBs are defined as the dioxins. According to the current scientific knowledge, the source categories and the formation processes of PCB and HCB are considered to be similar to those of unintentionally produced dioxins. Therefore, it is assumed that the release of PCBs and HCB has also been reduced through the dioxins reduction measures. 

Brown JF, Frame GM, Olson DR, et al. 1995. The sources of coplanar PCBs. Organohalogen Compounds 26 427-430. 

The polychlorinated biphenyls (PCBs, coplanar biphenyls) have been used in a large variety of applications as dielectric and heat transfer fluids, lubricating oils, plasticizers, wax extenders, and flame retardants. Their industrial use and manufacture in the USA were terminated by 1977. Unfortunately, PCBs persist in the environment. The products used commercially were actually mixtures of PCB isomers and homologs containing 12-68% chlorine. These chemicals are highly stable and highly lipophilic, poorly metabolized, and very resistant to environmental degradation they bioaccumulate in food chains. Food is the major source of PCB residues in humans. 

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