ANALYSIS OF CHROMOSOMAL-ABERRATIONS, SISTER-CHROMATID EXCHANGES AND MICRONUCLEI AMONG POWER LINESMEN WITH LONG-TERM EXPOSURE TO 50-HZ ELECTROMAGNETIC-FIELDS

Chromosomal aberrations, sister chromatid exchanges (SCEs), replicatio n indices and micronuclei in peripheral blood lymphocytes were analyse d among 27 nonsmoking power linesmen with considerable long-term expos ure to 50-Hz electromagnetic (EM) fields, and among 27 nonsmoking tele phone linesmen serving as a reference group, pairwise matched with the exposed workers for age and geographical region. Blood samples from t he two groups were collected, cultured and analysed in parallel. No di fferences between the groups were observed on analysis of SCEs, replic ation indices or micronuclei. However, the mean rate of lymphocytes wi th chromatid-type breaks was higher among the power linesmen (0.96% ga ps excluded, 1.41% gaps included) than among the reference group (0.44 % and 0.70%, respectively). The excess of aberrant cells was concentra ted among those power linesmen who had smoked earlier in their life. A lthough the interpretation is somewhat complicated by the confounding effect of previous smoking, these results suggest that exposure to 50- Hz EM fields is associated with a slight increase in chromatid breaks.