DETERMINATION OF POLYCHLORINATED BIPHENYL LEVELS IN THE SERUM OF RESIDENTS AND IN THE HOMOGENATES OF SEAFOOD FROM THE NEW-BEDFORD, MASSACHUSETTS, AREA - A COMPARISON OF EXPOSURE SOURCES THROUGH PATTERN-RECOGNITION TECHNIQUES

We measured the residues of polychlorinated biphenyls (PCBs) in the se rum of 23 residents of the New Bedford, Massachusetts, area and from t wo homogenates each of bluefish and lobsters from the same area. We us ed congener-specific and total Aroclor quantitative approaches, both o f which involved gas chromatography with electron capture detection. U sing gas chromatography mass spectrometry (electron ionization mode), we confirmed the presence of PCBs in the combined serum samples and in the aliquots of bluefish and lobsters. In measuring the PCB levels in serum, we found good agreement between the two electron capture detec tor approaches (r greater-than-or-equal-to 0.97) when the serum of spe cific congeners was compared to total Aroclor. We used univariate and multivariate quality control approaches to monitor these analyses. Ana lytical results for bluefish showed a better agreement between the two techniques than did those for lobsters; however, the small number of samples precluded any statistical comparison. We also measured levels of chlorinated pesticides in the serum samples of two groups of New Be dford residents, those with low PCB levels (< 15 ng/ml) and those with high PCB levels (greater-than-or-equal-to 15 ng/ml). We found that re sidents with high PCB levels also tended to have higher levels of hexa chlorobenzene (HCB) and 1,1-dichloro-2,2-di-(p-chlorophenyl) ethylene (p,p'-DDE). The higher concentration of all three analytes appears to be influenced by employment in the capacitor industry, by seafood cons umption, or both. Using Jaccard measures of similarity and principal c omponent analysis we compared the gas chromatographic patterns of PCBs found in the serum of New Bedford area residents with high serum PCBs with the patterns found in homogenates of lobsters (inclusive of all edible portions except the roe), in homogenates of bluefish fillets ta ken from local waters, and in serum from goats fed selected technical Aroclors (e.g. Aroclors 1016, 1242, 1254, or 1260). The patterns found in human serum samples were similar to the patterns found in lobster homogenates. Both of these patterns closely resembled patterns found i n the serum samples of the goat fed aroclor 1254, as demonstrated by b oth pattern recognition techniques. In addition, the chromatographic p atterns of human serum and of lobsters and bluefish homogenates all in dicated the presence of PCBs more characteristic of Aroclors 1016 or 1 242.