This study assessed the effect of RFR alone or in combination with X-rays human lymphocytes. A series of experiments was performed by two laboratories – one in Italy and one in the UK.

Blood from donors was exposed to RFR at GSM basic 935 MHz signal for 24 hours. In some experiments this was done either before or after the blood was exposed to X-rays – 1.0 Gy of 250 kVp at a dose rate of 1 Gy/min. All X-irradiated samples were compared with a parallel sample that received zero dose, and each RFR exposure was accompanied by sham exposures. The sham or active exposure was randomly made by the controlling computer and the coding for this was held until all assay data were complete. Microscope slides for assays were also read “blindly”. Both laboratories used a SAR of 1W/kg, and one laboratory also performed experiments at a SAR of 2 W/kg. Both laboratories performed chromosome aberration and micronucleus assays. One also measured sister chromatid exchanges, and the other performed an alkaline comet assay for DNA strand breakage.

By comparison with appropriate sham-exposed and control samples, no effect of RFR alone could be found for any of the assay endpoints. In addition RFR did not modify any measured effects of the x-radiation.