The geometric mean serum level of polychlorinated biphenyls (PCBs) of 458 persons in a communitywide study was 17.2 μg/L, with 80% to 90% having levels within the range found in other community groups. As a dependent variable, PCB levels were found to be positively related to age, even when controlled for all other variables associated with PCB level: sex, local fish consumption, obesity, serum cholesterol level, and alcohol consumption. No major point source of PCB contamination was found, and fish taken in the drainage of a major population center had mean PCB levels below the current enforceable Food and Drug Administration tolerance of 5 mg/kg. As an independent variable, serum PCB levels were positively associated with γ-glutamyl transpeptidase level, serum cholesterol level, and measured blood pressure. The PCB-blood pressure association, which was independent of age, sex, body mass index, and social class, must be confirmed in other exposed populations.
Kreiss K, Zack MM, Kimbrough RD, Needham LL, Smrek AL, Jones BT. Association of Blood Pressure and Polychlorinated Biphenyl Levels. JAMA. 1981;245(24):2505–2509. doi:10.1001/jama.1981.03310490023017