Human exposure to polychlorinated biphenyls in Greater New Bedford, Massachusetts: a prevalence study. 
A study was conducted in the community of Greater New Bedford, Massachusetts, from 1984 through 1987 to assess the prevalence of elevated levels of polychlorinated biphenyls (PCBs) in the serum of individuals aged 18 to 64 years who had resided in the area for at least 5 years.  Eight hundred and forty subjects were interviewed, examined, and tested in a cross-sectional sample of the towns of Acushnet, Dartmouth, and Fairhaven and the city of New Bedford.  Serum PCBs were measured to estimate the extent of human exposure.  Because of documented environmental contamination by PCBs in the New Bedford area, and the practice of recreational fishing in the harbor for food, a significant number of persons with elevated serum PCB levels were expected to be identified.  Instead, the prevalence of elevated serum PCBs in the sample was found to be typical of "unexposed" urban populations in the United States.  Only 1.3% of the subjects had serum PCB levels greater than 30 ppb.  The same percentage was observed among males (n = 391) and females (n = 449).  The geometric means of PCB levels were 4.3 ppb among males (Range = 0.50-60.9) and 4.2 ppb among females (Range = 0.38-154).  We conclude that the prevalence of elevated serum PCBs is low in the population of Greater New Bedford.