RT Report T1 Polychlorinated Biphenyls and Terphenyls (Second Edition) - Environmental Health Criteria 140 A1 World Health Organization, K1 polychlorinated biphenyl K1 polychlorinated terphenyl K1 pollutant K1 chemical K1 toxic substance K1 Pollution SN 92 4 1571403 YR 1993 FD 1993 LK https://wedocs.unep.org/handle/20.500.11822/29542 UL https://wedocs.unep.org/handle/20.500.11822/29542 NO Polychlorinated biphenyls (PCBs) were discovered before the turn of the century and their usefulness for industry, because of their physical properties, was recognized early. The PCBs have been used commercially, since 1930, as dielectric and heat-exchange fluids and in a variety of other applications. They have become widely distributed in the environment throughout the world, and are persistent and accumulate in food webs. DS UN Environment Document Repository RD Sep 21, 2026