Non-coplanar and coplanar polychlorinated biphenyls potentiate genotoxicity of aflatoxin B1 in a human hepatocyte line by enhancing CYP1A2 and CYP3A4 expression

Polychlorinated biphenyls (PCBs) have been recognized for over 25 years as global environmental contaminants. However, many PCB congeners may be relatively harmless, while a small group of PCB congeners are highly toxic to biota. The toxic coplanar PCB congeners are chlorinated at meta positions and at one or none of the ortho positions on the biphenyl ring, thus resembling 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in molecular configuration. In vitro and in vivo toxicity tests with rodents, fish, and birds have shown that the coplanar PCB congener 126 is almost as toxic as TCDD. Several coplanar PCBs (e.g., 77, 126, 105, 118) are present in biota at parts per billion concentrations, which is orders of magnitude higher than concentrations of TCDD. Thus, coplanar PCBs may account for over 95% of the dioxinlike toxic activity affecting biota, such as fish-eating birds in the Great Lakes. There is some evidence that the toxicokinetics of coplanar PCBs in organisms differs from that of other PCB homologues. If coplanar PCBs are more persistent than their homologues, they could become enriched in biota as they pass up through the food chain (i.e., trophic enrichment), or as overall PCB levels decline with time (i.e., temporal enrichment). Overall, the available data do not support the concept of trophic or temporal enrichment in the environment.Key words: polychlorinated biphenyls, coplanar, toxic equivalents, kinetics, mixed function oxidase, 7-ethoxyresorufin-O-deethylase.

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Derivation and Properties of Recombinant Fab Antibodies to Coplanar Polychlorinated Biphenyls

Journal of Agricultural and Food Chemistry ◽

10.1021/jf991208a ◽

2000 ◽

Vol 48 (6) ◽

pp. 2614-2624 ◽

Cited By ~ 11

Author(s):

Ya-Wen Chiu ◽

Rongliang Chen ◽

Qing X. Li ◽

Alexander E. Karu

Keyword(s):

Polychlorinated Biphenyls ◽

Coplanar Polychlorinated Biphenyls

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Neurochemical Effects of Co-Planar and Non-Coplanar Polychlorinated Biphenyls

Neurotoxicology and Teratology ◽

10.1016/s0892-0362(98)80571-0 ◽

1998 ◽

Vol 20 (3) ◽

pp. 349-350 ◽

Cited By ~ 6

Keyword(s):

Polychlorinated Biphenyls ◽

Coplanar Polychlorinated Biphenyls

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Rapid Determination for TEQ Evaluation of Dioxins/Furans(PCDD/DFs) and Coplanar Polychlorinated Biphenyls(Coplanar PCBs) by Use of Indicator Isomer.

Journal of Environmental Chemistry ◽

10.5985/jec.13.17 ◽

2003 ◽

Vol 13 (1) ◽

pp. 17-29 ◽

Cited By ~ 6

Author(s):

Motoi SHIBAYAMA ◽

Atsuhiro HAYASHI ◽

Tsuyoshi INOUE ◽

Takumi TAKASUGA

Keyword(s):

Polychlorinated Biphenyls ◽

Rapid Determination ◽

Coplanar Pcbs ◽

Coplanar Polychlorinated Biphenyls

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Coplanar Polychlorinated Biphenyls in Aroclor and Kanechlor Mixtures

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/70.3.451 ◽

1987 ◽

Vol 70 (3) ◽

pp. 451-454 ◽

Cited By ~ 1

Author(s):

Narayanan Kannan ◽

Shinsuke Tan Abe ◽

Tadaaki Wakimoto ◽

Ryo Tatsukawa

Keyword(s):

Polychlorinated Biphenyls ◽

Aroclor 1254 ◽

Coplanar Pcbs ◽

Aroclor 1248 ◽

Coplanar Polychlorinated Biphenyls

Abstract Three congeners of coplanar PCBs (non-0-0 -chlorine-substituted polychlorinated biphenyls) were determined in representative commercial PCB preparations. The 3,3,4,4 -tetrachlorobiphenyl was highest in Kanechlor 400 (8500 μg/g) and Aroclor 1248 (6060 μg/ g) followed by Kanechlors 300, 500, and 600 and Aroclors 1242, 1254, and 1260 in that order. The toxic 3,3',4,4',5-pentachlorobiphenyl and 3,3',4,4',5,5'-hexachlorobiphenyl were also detected in those mixtures. The highest concentrations of 3,3',4,4',5-pentachlorobiphenyl were found in Kanechlor 400 (89.3 μg/g) and Aroclor 1248 (62.3 μg/g) followed by Kanechlors 500, 300, and 600 and Aroclors 1254,1242, and 1260 in that order. The 3,3',4,4',5,5-hexwhlorobiphenyl was detected in all Kanechlor mixtures, with the highest concentration (1.16 μg/g) in Kanechlor 500. However, among Aroclor mixtures, it was detected only in Aroclor 1254 at a concentration of 0.66 jtg/g. The importance of these toxic constituents in PCB mixtures is worth considering in view of widespread pollution of the environment by PCBs.

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