EXPOSURE TO POWER FREQUENCY MAGNETIC-FIELDS AND RISK OF BREAST-CANCERIN THE UPPER CAPE-COD CANCER INCIDENCE STUDY

Investigators used a population-based case-control study to evaluate t he relationship between breast cancer risk and exposure to 60-Hz magne tic fields from various sources. There was no increase in breast cance r risk associated with (a) holding a job with high (odds ratio [OR] = 1.2; 95% confidence interval [CI] = 0.4, 3.4) or medium (OR = 0.9; 95% CI = 0.5, 1.7) exposure to magnetic fields; (b) living in a home heat ed electrically (OR = 1.0; 95% CI = 0.7, 1.4); or (c) sleeping with an electric blanket (OR = 1.0; 95% CI = 0.7, 1.4). There was a nonsignif icant 50% increase in risk for subjects who lived within 152 m (500 ft ) of an electricity transmission line or substation (OR = 1.5; 95% CI = 0.6, 3.3). Although limited by small numbers and exposure misclassif ication, the data in this study did not support the hypothesis that ex posure to 60-Hz magnetic fields increases the risk of breast cancer in women.