ADULT LEUKEMIA RISK AND PERSONAL APPLIANCE USE - A PRELIMINARY-STUDY

The hypothesis that use of personal electric appliances may be associa ted with increased risk of acute nonlymphocytic leukemia in adults was tested using interview data from a previously completed case-control study of 114 cases and 133 controls conducted between 1981 and 1984. C ases were obtained from a population-based cancer registry in western Washington state, and controls were obtained from the same area by ran dom digit dialing. Of 32 electrical home appliances for which data on use were available for adult acute nonlymphocytic leukemia cases and c ontrols, three motor-driven personal appliances (electric razors, hair dryers, and massage units) were selected a priori because their use r epresents exposure to higher peak magnetic fields than that from most other home appliances. When compared on an ''ever used'' versus ''neve r used'' basis, use of one or more of these appliances was not associa ted with increased risk of leukemia in the population studied (odds ra tio (OR) = 0.71, 95% confidence interval (CI) 0.41-1.24). When the app liances were considered individually, massage units were more likely t o have been used by cases than by controls (OR = 3.00, 95% CI 1.43-6.3 2), while hair dryers were more likely to have been used by controls t han cases (OR = 0.38, 95% CI 0.22-0.66). There was a nonsignificant te ndency for electric razor use to differentiate the cases from controls (OR = 1.33, 95% CI 0.80-2.23). When reported daily time of use was st ratified, there was no overall increased risk with increased time of u se except for electric razors (p < 0.05). In addition to the analysis of appliance use data from the case-control study, the authors obtaine d several models of these motor-driven personal appliances and charact erized the magnetic fields they produce. Magnetic field flux density, or the B-field, and spectral measurements showed that partial body exp osure from such appliances may exceed 0.5 mTesla (root mean squared) a t rates-of-change exceeding 10 Tesla/sec. These epidemiologic data mus t be interpreted cautiously because the number of cases is limited and because of proxy reporting of appliance use for deceased cases. Never theless, the authors believe these data indicate that peak magnetic fi eld exposure from personal appliances warrants further investigation a s a possible risk factor for acute nonlymphocytic leukemia in adults.