Polychlorinated Biphenyl Congeners in Adipose Tissue Lipid and Serum of Past and Present Transformer Repair Workers and a Comparison Group

Polychlorinated Biphenyl Congeners in Adipose Tissue Lipid andSerum of Past and Present Transformer Repair Workers and a ComparisonGroup. FAIT, A., GROSSMAN, E., SELF, S., JEFFRIES, J., PELLIZZARI,E. D., AND EMMETT, E. A. (1989). Fundam. Appl. Toxicol 12, 42-55. The concentrations of individual PCB's were determined inboth serum and adipose tissue lipid from 35 transformer repairworkers currently exposed to PCBs, mainly Aroclor 1260, 17 previoustransformer repair workers, and 56 comparison workers neveroccupationally exposed to PCBs. The analysis used fused-silicacapillary gas chromatography with electron capture detector(FSCGC/ECD) and FSCGC with negative ion chemical ionizationmass spectrometry to verify PCB congener levels. Eighty-ninePCB peaks were identified and confirmed. More congeners weredetected in adipose tissue. In serum approximately 50% of peakswere below the level of detection. Statistical techniques toaccount for left and interval censoring allowed comparison ofconcentration distributions even where data were incomplete.We found that unquantifiable levels were unlikely to contributesubstantially to the true values for total PCBs] over and beyondthe contribution of the measured values. However, the totalserum PCBs] determined by FSCGC/ECD greatly exceeded that fromstandard packed cell gas chromatography (PCGC/ECD). The underestimationwas less marked for adipose samples. In serum the total PCBs]was highest in currently exposed workers and lowest in unexposedworkers, with past-exposed workers clearly intermediate. Inadipose tissue PCBs] in the currently exposed group was muchhigher than in the other two groups, in whom the distributionof results was broadly similar. In all worker groups hexachlorinatedand heptachlorinated species predominated followed by octachlorinatedand pentachlorinated. The relative distribution of individualPCB congeners in the three groups was similar although the amountsvaried. The seven major peaks in serum and adipose tissue were2,3,5,6,3',4',5'/2,3,4,5,2',4',5' hepta-CB; 2,3,4,2',3',5' hexa-CB;2,4,6,3',4',5'/ 2,4,5,2',4',5'/2,3,4,5,2',5' hexa-CB; 2,3,4,5,2',3',4'hepta-CB; 2,3,4,5,2',3',5',6'/2,3,4,5,6,2',3',5', octa-CB; 2,4,5,3',4',/3,4,5,2',3'penta-CB; and 2,3,4,2',3',4'/2,3,5,6,2',4',5'/2,3,4,5,2',4',6'multi-CB. The distribution of PCB peaks in our populations differsfrom that in capacitor workers (exposed to less highly chlorinatedPCBs) and from Yu-Cheng patients suggesting differing toxicpotentials from PCBs in these three circumstances.