[Occupational exposure to electromagnetic fields and its health effects in electric energy workers].

Power frequency (50 to 60 Hz) electromagnetic fields (EMF) are briefly characterised, EMF sources occurring in the electromagnetic industry are discussed, and methods for and problems involved in the evaluation of individual occupational EMF exposure are also presented. The results of certain cohort industrial and case-referent studies indicate slightly enhanced risk of brain cancer and leukaemia in the group under study. The meta-analysis of the results obtained from numerous studies, published recently, showed a relative risk (RR) of 1.1-1.3 for leukaemia, and of 1.1-1.2 for brain cancer. Only a few studies demonstrate a dose-effect relationship for malignant neoplasms which decreases the power of the hypothesis on the cause-effect relationship. Among health effects of EMF exposure in electric utility workers, other than malignant neoplasms, an increased risk of certain diseases of the circulatory and neurological systems has been reported. The difficulty in the assessment of individual exposure is the main problem in evaluating the relationship between EMF exposure and adverse health effects in electric utility workers. We hope to investigate this further.