PCBs: Production and Properties

Abstract

Polychlorinated biphenyls (generically referred to as PCBs) were industrial compounds which enjoyed wide usage between 1930 and the mid-1970’s (ATSDR, 1997; DeVoogt and Brinkman, 1989; Hutzinger et al., 1974). Desirable properties were thermal and chemical stability, low flammability, and low electrical conductance. When widespread environmental contamination by PCBs was confirmed in the late 1960s, there were concerns about human health effects and environmental impact. There is still no consensus on the significance of human health effects, but manufacture was discontinued in the US, Japan and western Europe by the late 1970’s; manufacture continued in some countries until 1990. Some products containing large amounts of PCBs, especially electrical capacitors and transformers, are still in service. Other reservoirs include landfills, water and sediments. The atmosphere is an important environmental reservoir as well as a major route of exposure and transfer among other matrices.