title: Decreased body weight in fetal rats after irradiation with 2450-MHz (CW) microwaves.
abstract: Female Sprague-Dawley (CD) rats were exposed to 2450-MHz (CW) microwave radiation at incident power densities of 0 or 40 mW/cm2 (SAR = 6.0 W/kg) for 100 min daily on the sixth through 15th day of gestation. One-time exposure to the same conditions increased average colonic temperatures 2 degrees C at the end of irradiation in pregnant rats of similar size. There were 23 sham-irradiated and 24 microwave-irradiated females. When these groups were compared on the 21st day of gestation, no significant differences were found in pregnancy rates; in the numbers of live, dead or total fetuses; nor in the incidences of external, visceral or skeletal anomalies or variations. However, mean fetal body weight was significantly (p = 0.0008) lower after microwave irradiation and was 9% less than that of sham-irradiated litters. Sternal ossification was also significantly delayed in the microwave-irradiated fetuses (p = 0.007). It is concluded that even though a change in the malformation rate is not effected in rats, a fetotoxic effect does occur due to microwave-exposure conditions which raise maternal rectal temperatures to approx. 40 degrees C and produce a specific absorption rate (SAR) greater than or equal to 6 W/kg in the dam.
mesh_terms: D000818:Animals; D001835:Body Weight / Q000528:radiation effects*; D005260:Female; D005333:Fetus / Q000528:radiation effects*; D008872:Microwaves / Q000009:adverse effects*; D011247:Pregnancy; D051381:Rats; D011919:Rats, Inbred Strains