MAGNETIC-FIELDS AND CHILDHOOD-CANCER - A POOLED ANALYSIS OF 2 SCANDINAVIAN STUDIES

To test the hypothesis that exposure to magnetic fields, of the type g enerated by high voltage installations, increases cancer incidence in children, the original data from two case-control studies were pooled. The Swedish study was based on children living within 300 m from tran smission Lines, and the Danish study on the total population of Denmar k. In both these studies, national cancer registries were used to iden tify cases of Leukaemia, lymphoma or central nervous system tumour. Co ntrols were selected randomly from the study populations. Magnetic fie ld exposure was assessed through theoretical calculations of the magne tic fields before the time of diagnosis. An elevated relative risk of childhood leukaemia was found for calculated magnetic field levels of greater than or equal to 0.2 mu T, estimated at 2.0 (95% CI 1.0-4.1), and for magnetic field levels of greater than or equal to 0.5 mu T, es timated at 5.1 (95% CI 2.1-12.6). The results support the hypothesis o f an association between magnetic fields and childhood leukaemia.