polychlorinated biphenyl

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Related to Aroclors: Pcbs

polychlorinated biphenyl

or

PCB,

any of a group of organic compounds originally widely used in industrial processes but later found to be dangerous environmental pollutants. Polychlorinated biphenyl is a fat-soluble, water-insoluble hydrocarbon containing chlorine. It is extremely stable, withstanding temperatures of up to 1,600°F; (870°C;), is fire-resistant, and has been used as a heat-transfer and insulating fluid in cooling systems and electrical equipment; it has also been used in sealants, rubber, paints, plastics, printing ink, and insecticides. The chemical has entered the environment largely as a pollutant from equipment leaks, the weathering of many materials that contain PCB, and through interaction with food products. PCBs are not readily biodegradable. Production has been banned in several industrialized countries; the United States stopped producing PCBs in 1977.

polychlorinated biphenyl

[¦päl·i′klȯr·ə‚nād·əd bī′fen·əl]
(organic chemistry)
Any member of the group of chlorinated isomers of biphenyl. Abbreviated PCB.
References in periodicals archive ?
Comparative carcinogenicity in Sprague-Dawley rats of the polychlorinated biphenyl mixtures Aroclors 1016, 1242, 1254, and 1260.
RM 8504, Transformer Oil, is intended to be used as a diluent oil with transformer oil Standard Reference Materials (SRMs) 3075 to 3080 and SRM 3090 [1] when developing and validating methods for the determination of polychlorinated biphenyls (PCBs) as Aroclors (1) in transformer oil or similar matrices.
Aroclors 1221, 1232, 1242, 1016, and 1248) were not present in any of the fish tissues.
Certain health risks of PCBs were almost immediately apparent as workers making Aroclors suffered severe skin damage.
For the organic components, these include six individual Aroclors in a water-soluble solvent (methanol) and the same six individual Aroclors in transformer oil (Table 1).
Animal studies conducted in rodents and nonhuman primates exposed to PCBs and dioxins have observed similar outcomes to studies of humans, including suppressed antibody response to immunization with sheep red blood cells and reduced response to mitogen in lymphocyte proliferation assays, and provide a convincing body of evidence for the immunosuppressive effects of Aroclors and DL-PCBs [as reviewed by Kerkvliet (2009), Selgrade (2007), and Tryphonas (1995)].
Aroclor 1254) and expected chemical composition can vary from batch to batch (Kodavanti et al.
In addition, Aroclors and ortho-substituted PCBs contain or are partial agonists that suppress TCDD-induced immunotoxicity, presumably through competitive binding to the AhR (Peters et al.
Differential binding affinities of PCBs, HO-PCBs, and Aroclors with recombinant human, rainbow trout (Onchorhynkiss mykiss), and green anole (Anolis carolinensis) estrogen receptors, using a semi-high throughput competitive binding assay.
Effects of Aroclors and individual PCB congeners on activation of the human androgen receptor in vitro.
It was prevalent in harbor sediments consistent with the predominant Aroclors used by the area's industries (Brown and Wagner 1990; Weaver 1984).
Common examples are Aroclors 1242, 1248, and 1254, which contain 42, 48, and 54% chlorine by weight, respectively.