RESIDENTIAL EXPOSURE TO 60-HERTZ MAGNETIC-FIELDS AND ADULT CANCERS INTAIWAN

We conducted a case control study, using matching on date of birth, se x, and date of diagnosis, in northern Taiwan to evaluate the risks of adult leukemia, brain tumors, and female breast cancers in relation to residential exposure to 60-Hertz (Hz) magnetic fields. Cases were per sons with newly diagnosed cancers reported to the cancer registry betw een 1987 and 1992, and controls were persons with cancers of sites oth er than those previously suspected of being associated with magnetic f ields. Magnetic fields in the residences occupied by the study subject s at the time of diagnosis were estimated from high-voltage transmissi on lines. The results were based on the separate analysis of 870 cases of leukemia, 577 brain tumors, and 1,980 female breast cancers. We es timated the risk of leukemia among those exposed to magnetic fields of >0.2 microtesla (mu T), relative to the risk among those exposed to f ields of <0.1 mu T; the odds ratio was 1.4 [95% confidence interval (C I) = 1.0-1.9]. For distance <50 meters relative to greater than or equ al to 100 meters, the relative risk was 2.0 (95% CI = 1.4-2.9). For br ain tumors and female breast cancers, the odds ratios were close to un ity.