Fingerprinting PCB patterns among Mohawk women

Abstract

This study examined the association of contaminated fish consumption and polychlorinated biphenyl ( PCB ) body burden by comparing the similarity of the congener pattern in yellow perch, caught near the point source of industrial pollution, and in other local fish to the pattern found in the breast milk of Mohawk women from Akwesasne, a Native American community located along the St. Lawrence River in New York, Ontario, and Quebec. The similarity is defined by the weighted Euclidean distance between two congener patterns. Ninety -seven Mohawk mothers participated and provided samples of breast milk. One hundred fifty -four nursing women from the Supplemental Nutrition Program for Women, Infants and Children ( WIC ) of Warren and Schoharie counties, New York, who gave birth during the same time period, were used as the comparison group. Results revealed that the breast milk of the Mohawk women, who ate the most local fish, had a congener pattern that more closely resembled that of perch caught near the waste site or average sampled fish caught in the Reserve than Mohawk women who ate less fish or the controls. The outcome demonstrates how PCBs may be``fingerprinted'' as they migrate offsite from industrial sources and ultimately result in human exposure.

Environmental and occupational exposures and serum PCB concentrations and patterns among Mohawk men at Akwesasne

“…Similarly, men with jobs that were evaluated by industrial hygienists as entailing exposure to PCBs were significantly more likely than men without occupational exposure to have a serum congener pattern that resembled Aroclor 1248, the commercial PCB mixture used at all three local facilities. The association between local fish consumption and serum congener pattern among Mohawk men is consistent with our earlier work that showed nursing Mohawk women who ate the local fish most also showed congener patterns in their breast milk that more closely resembled the pattern in contaminated local fish (Hwang et al, 2001). These findings strengthen the argument that local exposures to PCBs through fish consumption or occupation have resulted in exposure to PCBs among the Mohawk people.…”

“…However, in our previous work, we weighted the Euclidean distances for each congener by a factor representing its relative half-life, and the results were similar to those without such weighting (Hwang et al, 2001). Another limitation of the study pertains to the accuracy of the self-reported information regarding lifetime fish consumption.…”

“…In our previous ''fingerprinting'' articles (Hwang et al, 1993(Hwang et al, , 2001, we compared the statistical properties of the Euclidean distance measure that we used in this analysis with other possible approaches such as principal components analysis, cluster analysis, and the Jaccard and other similarity coefficients. We concluded that each method has its strengths and weaknesses and that none is uniformly superior.…”

“…Using a Euclidean distance measure, we previously demonstrated that contaminated fish caught offshore from the General Motors facility had a congener profile that more closely matched Aroclor 1248 than did fish obtained elsewhere at Akwesasne (Hwang et al, 1993). In turn, nursing Mohawk women who had the greatest exposure to PCBs from local fish consumption had a congener pattern in their breast milk that more closely resembled that in contaminated fish caught off-shore from the General Motors facility (Hwang et al, 2001). The current study extends this analysis to Mohawk men, and matches congener patterns in serum with those in outdoor air as well as local fish and Aroclor 1248 to ''fingerprint'' PCBs as they migrate from hazardous waste sites and ultimately result in human exposure.…”

“…Conversely, the less similar the congener patterns, the greater the Euclidean distance between the serum and source sample. More details about the properties of this Euclidean distance measure are available elsewhere (Hwang et al, 1993(Hwang et al, , 2001.…”