Effects of radiofrequency radiation and simultaneous exposure with mitomycin C on the frequency of sister chromatid exchanges in chinese hamster ovary cells

Abstract

Chinese hamster ovary (CHO) cells were exposed for 2 hr with and without mitomycin C (MMC) (1 × 10⁻⁸M) to pulsed wave radiofrequency radiation (RFR) at 2450 MHz. The repetition rate of 25,000 pulses per sec (pps), pulse width of 10 μs, and exposure geometry used, resulted in a specific absorption rate (SAR) of 33.8 W/kg. The following exposure regimens were used: 1) a 37°C water bath control; 2) a water bath temperature control (TC) in which the continuously monitored medium temperature closely followed the temperature rise in the RFR-exposed flasks; and 3) the RFR-exposed cells in a water bath set at 37°C prior to exposure. RFR exposure resulted in a maximum cell culture medium temperature of 39.2°C. In the absence of MMC, there was no significant increase in sister chromatid exchange (SCE) in the RFR-exposed or TC groups over that of the 37°C control. When a simultaneous treatment of RFR and MMC occurred there was no statistical difference in SCE frequency from that caused by chemical treatment alone.