Regulation of PCBs under TSCA 6 e

Of the myriad of chemical substances regulated under TSCA, PCBs are subject to unique treatment. Indeed, upon enactment of TSCA, Congress prohibited the manufacture, processing, distribution, and use of PCBs in any manner other than a totally enclosed manner, subject to exceptions that may be issued by EPA if it finds that such exception would not result in an unreasonable risk of injury to health or the environment. These restrictions were unique because at the time TSCA was passed it did not single out any other chemical for a ban in this maimer. 

PCBs describe a group of over two hundred structurally-related chemical compounds, or congeners. Each congener has two benzene rings and a range of chlorine atoms. Colorless crystals in pure form, commercial PCB products are liquids because the melting point is depressed when PCBs are mixed PCBs are practically insoluble in water and soluble in oils and organic solvents. 

PCBs were first manufactured commercially in 1929. Because of the insulating capacity and flame retardant nature of PCBs, they were widely used as coolants and lubricants in transformers and electrical equipment. PCBs were also commonly used in the formulation of a great variety of common products such as plastics, paints and varnishes, pesticides, carbonless copy paper, adhesives, sealants, newsprint, fluorescent light ballasts, and 

PCBs are persistent in the environment and tend to accumulate in living creatures and to then enter the food chain where they concentrate. Widespread distribution of PCBs in soil and water was first determined in the 1960s. 

Acute exposure to high concentrations of PCBs causes a persistent form of acne called chlorine-acne or chloracne. Based on sufficient evidence of carcinogenicity in experimental animals, the EPA, the International Agency for Research on Cancerand the National Toxicology Program have all classified some PCBs as possibly causing cancer in humans.  

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