1) To evaluate the effect of 600 MHz radiofrequency irradiation on colonic and tail skin temperature of the rat at ambient temperatures of 20, 28 or 35°C. 2) To evaluate the utility of an allometric function to predict the effect of ambient temperature on the SAR needed to elevate the body temperature of various laboratory mammals. Data from this study were combined with data from earlier studies to assess the impact of varying ambient temperatures on the thermogenic effect of radiofrequency irradiation in different species.
Exposure duration: 90 min
1) The SAR needed to elevate colonic and tail skin temperature decreased with increasing ambient temperature. For example, a 0.5°C elevation in colonic temperature occurred at SARs of 4.3, 0.9 and 0.5 W/kg when ambient temperature was maintained at 20, 28 and 35°C, respectively.
2) In species ranging in mass from 0.02 to 3.2 kg, a double logarithmic plot of body mass versus SAR needed to elevate colonic temperature by 0.5°C was linear and inverse. The highly correlated allometric relationship shows that, as body mass decreases, the relative impact of ambient temperature on the thermogenic effect of radiofrequency irradiation increases.