The pKZ1 recombination mutagenesis model was used to determine if exposure to radiofrequency radiation (whole-body SAR 4 W/kg) would induce somatic intrachromosomal recombination in spleen tissue. The pKZ1 recombination mutagenesis model enabels detection of somatic intrachromosomal recombination inversion events in response to DNA-damaging agents.
|Pulse width||0.6 ms|
|Repetition frequency||217 Hz|
|Chamber||The waveguide made of aluminium was a WG3 with a rectangular cross section with external dimensions of 296 mm x 150 mm and a length of 1700 mm. Coaxial to waveguide E-field exciter antennae were built into each end. The RF radiation received by the antenna at the other end of the waveguide was dissipated in a resistive high-power coaxial attenuator. Two tuning screws allowed to minimize the amount of reflected energy.|
|Setup||The waveguide had 13 access ports aligned along its length and contained a solid block of Styrofoam that had 13 shaped polycarbonate tubes glued into it. The tubes had bayonet connectors that received and locked the mouse holders into position. The mouse holder tubes (length 173 mm; diameter 32 mm inside, 36 mm outside) made of polycarbonate enabled restraint of a 30-g mouse. The capsules were fully contained except for the hole in the capsule near the nose of the mouse for letting in the air.|
|Additional info||The mice in the multiple-exposure experiments were placed randomly in the waveguide to average out any variations in SAR along the waveguide. Matched sham-exposed mice were placed in the exposure apparatus with the air flow on but no RF radiation for the same period as the treated mice.|
|SAR||4 W/kg||average over mass||measured and calculated||whole body||-|
There was no significant difference between the control and treated animals in the 1- and 5-day group. But there was a significant reduction in inversions below the spontaneous frequency in the 25-day group. The results suggest that exposure to radiofrequency radiation can lead to a perturbation in recombination frequency which may have implications for recombination repair of DNA.