ID Number		600
Study Type		In Vivo
Model		27 MHz (PW) exposure to pregnant rats and analysis of teratogenicity and reproduction
Details		Sprague-Dawley rats (pregnant dams) were exposed on day 9 of gestation to 27.12 MHz RF (PW) for up to 60 minutes at SARs between 2.8 – 5.6 W/kg using commercial shortwave diathermy units. Core temperature of the dam increased from 0.4 to 1.3 C with exposure. Following exposure, fetuses were isolated and analyzed. No change in mean weight or number of malformations was observed, although the percent of resorbed implantations increased with increasing diathermy treatment from one of the devices. The authors point out that localized temperature increases in excess of maternal rectal temperature may have contributed to these effects. Additional teratogenicity studies were performed using the above exposure parameters to produce higher core temperature elevations in the pregnant dams. Core temperature increases of 3.5 – 5 degrees were strongly associated with an increased fetus resorption rate and microphthalmia and other malformations in surviving pups. Studies on the reproductive function were also performed in Sprague-Dawley virgin females exposed as above for 1 hr/day, 5 days/wk, for a total of 25 hr over 5 wks in a restraining box (Health Physics 56:521, 1989). Restraint caused a slight increase in rectal temperature, but there was no significant difference observed between the irradiated and sham-irradiated groups. In the exposed groups there was a decrease in the number of rats that mated as well as the number of mating rats that became pregnant. There were no differences in the number of pups per litter, number of implantation sites, or fetal weight. No difference in congenital malformations was observed. The authors concluded that fertility of shortwave diathermy operators could be affected if the operator remains close to the console during the treatment period. The results of this paper are, however, inconsistent with the weight of evidence that reproductive effects of RF exposure are thermally based.
Findings		Effects (only at thermal levels)
Status		Completed With Publication
Principal Investigator		Cumberland Coll. of Health Sciences, Australia
Funding Agency		Private/Instit.
Country		AUSTRALIA
References		Brown-Woodman, PD et al. J. Bioelectricity, (1988) 7:57-67 Brown-Woodman, PD et al. Industrial Health, (1988) 26:1-10 Brown-Woodman, PD et al. Health Phys., (1989) 56:521-525
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