Cytogenetic Effects of Microwave Irradiation on Male Germ Cells of the Mouse

Summary

Hybrid male mice were exposed to 2·45 GHz microwaves for 30 min/day, 6 days a week for two consecutive weeks at power densities of 1·0, 100 or 400 W m⁻², with sham-exposed controls. Rectal temperatures before and after exposure were measured on days 1, 6 and 12. Measurements made on day 1 were treated with caution because of heterogeneity in rectal temperatures taken before exposure between the groups of mice given different treatments. On days 6 and 12, rectal temperatures rose by approximately 1°C in mice sham exposed, or exposed to 1 W m⁻² or 100 W m⁻². Only in the group of mice exposed to 400 W m⁻² was the mean rise in rectal temperature during exposure (about 3°C) significantly increased above the sham value. In groups killed 2–3 days after treatment (mainly meiotic exposure) frequencies of chromosome aberrations in spermatocytes showed no significant heterogeneity although the highest frequency of 1·5 per cent was at the highest (400 W m⁻² power density. Another group killed 30 days after 100 W m⁻² exposures (spermatogonial sampling) showed no significant increase over controls in chromosome aberration frequency. There was a small but significant increase in sperm count with increasing power density in mice killed 12–13 days after exposure, but a non-significant one in those exposed as spermatogonia (killed 41 days later). Thus effects were markedly less severe than those reported previously by Manikowska-Czerska et al. (1985) with a very similar radiation regime and were probably caused by the temperature enhancement.

• mcrowaves
• chromosome aberrations
• mouse germ cells
• sperm abnormalities
• sperm counts