PCBs are synonymous with the dangers of worldwide environmental contamination. Chemically they are chlorinated hydrocarbons. PCBs are synonymous with the dangers of worldwide environmental contamination. Chemically, they belong to the chlorinated hydrocarbons and caused by uncontrolled chlorination of biphenyl. It is a mixture that can have the consistency of a low-viscosity oil, wax or the viscosity of the resin depending on the quantity of chlorine. Due to these properties they were used until 1972 as a lubricant in the form of oils, high pressure pump oils and screw grease. They were used as additives in plastics, adhesives, paper coatings, impregnating agents and flame retardants (E.g.
in carpets), putties, Spachtelungs -, sealing and potting compounds. PCBs were used as a carrier substance for insecticides. They are extremely stable and especially during industrial production processes and the burning of PCB containing materials in Waste incineration plants into the environment may occur in which significant amounts of highly toxic, chlorinated Dibenzofurans and dioxins, including the “Sevesogift” of 2,3,7,8 – TCDD (Tetrachlordibenzoparadioxin). Because they are stable against biodegradation and environmental influences over the decades, can be found today the sectors of the environment and biological systems in which PCBs can not be detected. They spread through air and water and improve greatly in vegetable and animal fats and thus in the food chain. Especially fish and milk contain often appreciable amounts.
Polychlorinated biphenyls can trigger in addition to their hormonal effect of cancer, chlorine acne or pigmentation of the skin and nails (Yusho disease), eye inflammation and swelling of the limbs. Having regard to the effects, the only German manufacturer, Bayer AG, restricted use on so-called closed systems such as transformers, condensers and hydraulic oils from 1972. Production and placing on the market of PCBs are banned in the EU since 1989. The Federal Republic belongs to the regions of the world most heavily burdened by the PCB residues, approximately 60 000 tonnes are in the application, which can arrive in fires in the environment. The resistant chemicals only in special high-temperature incineration can be destroyed. This dioxin care must be taken to avoid the possible formation of even more poisonous furans and the infamous “Sevesogiftes”.