Dominant lethal mutation test in male mice exposed to 900 MHz radiofrequency fields

•The dominant lethal mutation test was conducted in male mice.•Male mice exposed to radiofrequency fields (RF) were mated with un-exposed females.•The contents of the uteri of females were examined during 4 weeks mating.•Overall data indicated an absence of mutagenic effect of RF exposure.

Adult male ICR mice were exposed to continuous wave 900 MHz radiofrequency fields (RF) at 1.6 mW/cm2 power intensity (whole body average specific absorption rate of 0.731 W/kg) for 4 hour/day for 15 days. At the end of exposure, each mouse was caged with 3 mature virgin female mice for mating. After 7 days, each male mouse was transferred to a fresh cage and mated with a second batch of 3 females. This process was repeated for a total of 4 consecutive weeks. Sham exposed male mice and those subjected to an acute 2 Gy γ-irradiation (GR) were handled similarly and used as un-exposed and positive controls, respectively. All females were sacrificed on the 18th day of gestation and presumptive mating and, the contents in their uteri were examined. The overall observations during the 4 weeks of mating indicated that the un-exposed female mice mated to RF-exposed male mice showed no significant differences in the percentage of pregnancies, total implants, live implants and dead implants when compared with those mated with sham-exposed mice. In contrast, female mice mated with GR-exposed males showed a consistent pattern of significant differences in the above indices in each and all 4 weeks of mating. Thus, the data indicated an absence of mutagenic potential of RF exposure in the germ cells of male mice.