High Peak Power Microwave Pulses at 1.3. GHz: Effects on Fixed Interval and Reaction Time Performance in Rats

摘要

The current safety standards for radiofrequency and microwave exposure do not limit the peak power of microwave pulses for general or occupational exposures. To determine whether high peak power microwave pulses can alter known thresholds of behavioral disruption, four Long-Evans male rats were exposed to peak powers of 496.7, 336.7, and 146.7 kW in a waveguide exposure system while performing a time-related behavioral task. The task consisted of two components: a fixed interval schedule of reinforcement on one response lever and reaction time on a second lever. Responding on each lever was dependent on visual signals displayed through the translucent plastic levers. Trained rats performed the behavioral task during exposure to 1.3-GHz microwave pulses at a pulse repetition rate of 10 Hz. Significant changes occurred in behavioral performance. Session time increased, response rates decreased, and reaction times significantly increased at whole-body SARs of 6.3 and 10.5 W/kg. The alteration of behavior in this study occurred at a whole body SAR between 3.5 and 6.3 W/kg, which is consistent with previous estimates of 4 W/kg as the threshold for behavioral alteration. The high peak power pulses used in this study did not alter this threshold, suggesting that the primary effect must be tissue heating. (aw)