title: Cytogenetic effects of microwave irradiation on male germ cells of the mouse.
abstract: 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 degree 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 degrees 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.
mesh_terms: D000818:Animals; D001831:Body Temperature; D002869:Chromosome Aberrations; D008297:Male; D051379:Mice; D008872:Microwaves / Q000009:adverse effects*; D009929:Organ Size; D012730:Sex Chromosomes / Q000528:radiation effects; D013076:Sperm Count; D013094:Spermatozoa / Q000528:radiation effects* / Q000648:ultrastructure