BREAST-CANCER AMONG WOMEN EXPOSED TO POLYBROMINATED BIPHENYLS

We conducted a nested case-control study with 1,925 women enrolled in a polybrominated biphenyl (PBB) registry to examine the association be tween breast cancer and serum PBBs. Twenty women who developed breast cancer were matched to 290 control subjects on sex, race, and age. Wom en with serum PBB levels of 2.0-3.0 parts per billion (ppb) [odds rati o (OR) = 3.5; 95% confidence interval (CI) = 0.9-13] or 4.0 ppb or gre ater (OR = 3.1; 95% CI = 0.8-12) had a higher estimated risk for breas t cancer than women with less than 2.0 ppb. The odds ratios were uncha nged when available breast cancer risk factors were included in the an alysis.