Chromosome damage and micronucleus formation in human blood lymphocytes exposed in vitro to radiofrequency radiation at a cellular telephone frequency (847.74 MHz, CDMA)

Peripheral blood samples collected from four healthy nonsmoking human volun teers were diluted with tissue culture medium and exposed in vitro for 24 h to 847.74 MHz radiofrequency (RF) radiation (continuous wave), a frequency employed for cellular telephone communications. A code division multiple a ccess (CDMA) technology was used with a nominal net forward power of 75 W a nd a nominal power density of 950 W/m(2) (95 mW/cm(2)). The mean specific a bsorption rate (SAR) was 4.9 or 5.5 W/kg. Blood aliquots that were sham-exp osed or exposed in vitro to an acute dose of 1.5 Gy of gamma radiation were included in the study as controls. The temperatures of the medium during R F-radiation and sham exposures in the Radial Transmission Line facility wer e controlled at 37 +/- 0.3 degreesC. Immediately after the exposures, lymph ocytes were cultured at 37 +/- 1 degreesC for 48 or 72 h. The extent of gen etic damage was assessed from the incidence of chromosome aberrations and m icronuclei. The kinetics of cell proliferation was determined from the mito tic indices in 48-h cultures and from the incidence of binucleate cells in 72-h cultures. The data indicated no significant differences between RF-rad iation-exposed and sham-exposed lymphocytes with respect to mitotic indices , frequencies of exchange aberrations, excess fragments, binucleate cells, and micronuclei. The response of gamma -irradiated lymphocytes was signific antly different from that of both RF-radiation-exposed and sham-exposed cel ls for all of these indices. Thus there was no evidence for induction of ch romosome aberrations and micronuclei in human blood lymphocytes exposed in vitro for 24 h to 847.74 MHz RF radiation (CDMA) at SARs of 4.9 or 5.5 W/kg . (C) 2001 by Radiation Research Society.