Measurement of DNA damage in mammalian cells exposed in vitro to radiofrequency fields at SARs of 3-5 W/kg

In the present study, we determined whether exposure of mammalian cells to 3.2-5.1 W/kg specific absorption rate (SAR) radiofrequency fields could ind uce DNA damage in murine C3H 10T1/2 fibroblasts. Cell cultures were exposed to 847.74 MHz code-division multiple access (CDMA) and 835.62 frequency-di vision multiple access (FDMA) modulated radiations in radial transmission l ine (RTL) irradiators in which the temperature was regulated to 37.0 +/-0.3 degreesC. Using the alkaline comet assay to measure DNA damage, we found n o statistically significant differences in either comet moment or comet len gth between sham-exposed cells and those exposed for 2, 4 or 24 h to CDMA o r FDMA radiations in either exponentially growing or plateau-phase cells. F urther, a 4-h incubation after the 2-h exposure resulted in no significant changes in comet moment or comet length. Our results show that exposure of cultured C3H 10T1/2 cells at 37 degreesC CDMA or FDMA at SAR values of up t o 5.1 W/kg did not induce measurable DNA damage. (C) 2001 by Radiation Rese arch Society.