Structural identification of polychlorinated biphenyls in commercial mixtures by gas-liquid chromatography, nuclear magnetic resonance and mass spectrometry

Sissons, D.J.; Welti, Dieter H.

doi:10.1016/s0021-9673(00)95526-2

Cited by 219 publications

(57 citation statements)

References 18 publications

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“…Aroclor 1254 induces both the PB-and 3-MC inducible monooxygenases (24)(25)(26) and cytochromes P450a-P-450e (21,(27)(28)(29)(30)(31) and resemble PB plus 3-MC (coadministered) in its mode of drug-metabolizing enzyme induction. In retrospect, this bifunctional or "mixed-type" induction pattern for Aroclor 1254 was not unexpected since the commercial PCB formulations are complex mixtures of isomers and congeners which contribute to the observed induction activity (1,(32)(33)(34).…”

Section: **Department Of Agricultural Chemistry Kyoto University Kyotomentioning

confidence: 90%

“…The problem was partially resolved when 2,3,7,8-tetrachlorodibenzofuran, a contaminant formed in the synthesis of 2,2',4,4',5,5'-hexachlorobiphenyl, was shown to be the active AHH-inducing component of the commercially available isomeric hexachlorobiphenyl (065). Since several di-ortho-substituted PCBs, including 2,2',4,4',5,5'-and 2,2',3,4,4',5'-hexachlorobiphenyl, are major components of the commercial mixtures (32)(33)(34), the microsomal mixed-function oxidase enzyme induction activities of all the di-ortho coplanar PCBs analogs were determined (Fig. 4).…”

Section: Di-ortho Coplanar Pcbsmentioning

confidence: 99%

See 1 more Smart Citation

PCBs: structure–function relationships and mechanism of action

Safe¹,

Bandiera²,

Sawyer³

et al. 1985

Environ Health Perspect

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Numerous reports have illustrated the versatility of polychlorinated biphenyls (PCBs) and related halogenated aromatics as inducers of drug-metabolizing enzymes and the activity of individual compounds are remarkably dependent on structure. The most active PCB congeners,3,4,4',3,3',4,3,3',4,4',3',4,4',5,, are substituted at both para and at two or more meta positions. The four coplanar PCBs resembled 3-methylcholanthrene (3-MC) and 2,3,7,3,7, in their mode of induction of the hepatic drug-metabolizing enzymes. These compounds induced rat hepatic microsomal benzo(a)pyrene hydroxylase (aryl hydrocarbon hydroxylase, AHH) and cytochromes P-450a, P-450c and P-450d. 3,4,4',5-Tetrachlorobiphenyl, the least active coplanar PCB, also induced dimethylaminoantipyrine N-demethylase and cytochromes P-450b + e and resembled Aroclor 1254 as an inducer of the mixed-function oxidase system. Like Aroclor 1254, all the mono-ortho-and at least eight di-ortho-chloro analogs of the coplanar PCBs exhibited a "mixed-type" induction pattern and induced microsomal AHH, dimethylaminoantipyrine NM-demethylase and cytochromes P-450a-P-450e. Quantative structure-activity relationships (QSARs) there was an excellent correlation between AHH induction potencies and receptor binding avidities of these compounds and the order of activity was coplanar PCBs (3,3',4,3,3',4,4',3',4,4',5,5'-hexachlorobiphenyls) > 3,4,4',5-tetrachlorobiphenyl -mono-ortho coplanar PCBs > di-ortho coplanar PCBs. It was also apparent that the relative toxicities of this group of PCBs paralleled their biological potencies.The coplanar and mono-ortho coplanar PCBs also exhibit differential effects in the inbred C57BL/6J and DBA/2J mice. These compounds induce AHH and cause thymic atrophy in the former "responsive" mice whereas at comparable or higher doses none of these effects are observed in the nonresponsive DBD/ 2J mice. Since the responsiveness of these two mice strains is due to the presence of the Ah receptor protein in the C57BL/6J mice and its relatively low concentration in the DBA/2J mice, the results for the PCB cogeners support the proposed receptor-mediated mechanism of action.Although the precise structural requirements for ligand binding to the receptor have not been delineated, the halogenated aromatic hydrocarbons which exhibit the highest binding affinities for the receptor protein are approximate isostereomers of 2,3,7,8-TCDD. 2,3,4,4',5-Pentachlorobiphenyl elicits effects which are qualitatively similar to that of TCDD and the presence of the lateral 4'-substituent is required for this activity. Thus the 4'-substituted 2,3,4,5-tetrachlorobiphenyls have been used as probes for determining the substituent characteristics which favor binding to the receptor protein. Multiple regression analysis of the competitive binding EC50 values for 13 substituents gave the following equation: log (1/EC5O) = 1.53a + 1.47T + 1.09 HB + 4.08 where a is electronegativity, a is hydrophobicity, HB is hydrogen bonding and r is the correlation coefficient (r = 0.978). The ut...

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Section: **Department Of Agricultural Chemistry Kyoto University Kyotomentioning

confidence: 90%

Section: Di-ortho Coplanar Pcbsmentioning

confidence: 99%

PCBs: structure–function relationships and mechanism of action

Safe¹,

Bandiera²,

Sawyer³

et al. 1985

Environ Health Perspect

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show abstract

“…The 10% DC-200 (or OV-101) column described in the FDA Pesticide Analytical Manual (48) separates Aroclor 1254 into 14 peaks (57). These analytical columns do not give a highly defined representation of the Aroclor or PCB residue; several of the peaks in Aroclors result from mixtures of more than one chlorobiphenyl (34,(58)(59)(60). A column prepared from purified Apiezon L has been shown to separate a 54% chlorine PCB mixture into over 40 peaks (61).…”

Section: Determination Of Pcb Residuesmentioning

confidence: 99%

“…In the Ullmann coupling reaction of 2,4,5-trichloroiodobenzene, it has been reported (99) that the highly toxic 2,3,7,8-tetrachlorodibenzofuran is formed in 3% yield in addition to the expected 2,2',4,4',5,5'-hexachlorobiphenyl product. This hexachlorobiphenyl is a significant constituent of PCB mixtures (34,61,100), and has been singled out for biological studies by several workers (32,98,101). Careful purification and, if necessary, chemical analysis of symmetrical chlorobiphenyls prepared by the Ullmann coupling reaction (for dibenzofuran content) is suggested as a prerequisite to biological testing of the biphenyl.…”

Section: Chlorinated Dibenzofuransmentioning

confidence: 99%

Chemistry of PCBs and PBBs

Pomerantz¹,

Burke²,

Firestone³

et al. 1978

Environ Health Perspect

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“…OV-101 was selected as statibnary phase because very efficient capillary cohmms can be made with this phase and_ it is considerably less polar than Apiezon L. KovBts retention indices of the corresponding PCBs determined on Apiezon L are larger by 100 units than on OV-1Ol (ref. 4). Fig.…”

Section: Resultsmentioning

confidence: 99%