Chromosome aberrations in lymphocytes of high-voltage laboratory cable splicers exposed to electromagnetic fields

Thirteen high-voltage laboratory employees and 20 referents participated in a cross-sectional, matched-pairs study of cytogenetic damage. During cable testing the workers were exposed to static, alternating, or pulsed electric and magnetic fields. The alternating magnetic field levels of 50 Hz were 5-10 microT, occasionally much higher. Chromosome aberrations, sister chromatid exchanges, and aneuploidy were studied in peripheral blood lymphocytes. In addition, chromosome aberrations were investigated in lymphocyte cultures treated with hydroxyurea and caffeine, to inhibit deoxyribonucleic acid synthesis and repair. Among seven smoking laboratory employees the mean number of chromosome breaks/200 cells was 2.3, as compared with 0.7 for the job-matched referents. The comparable figures for inhibited cultures were 12.0 versus 6.0. No increase was detected in nonsmokers with either method. The other genetic parameters showed no differences between the exposed workers and the referents. The results support, to some extent, the hypothesis of an increased risk of genotoxic effects among high-voltage laboratory workers.