Record Display for the EPA National Library Catalog


Main Title Behavioural and Autonomic Thermoregulation in Hamsters during Microwave-Induced Heat Exposure.
Author Gordon, C. J. ; Long, M. D. ; Fehlner, K. S. ;
CORP Author Health Effects Research Lab., Research Triangle Park, NC.
Year Published 1984
Report Number EPA/600/J-84/364;
Stock Number PB86-169901
Additional Subjects Microwaves ; Radiation effects ; Thermoregulation ; Behavior ; Hamsters ; Exposure ; Heat ; Reprints ;
Library Call Number Additional Info Location Last
NTIS  PB86-169901 Some EPA libraries have a fiche copy filed under the call number shown. 07/26/2022
Collation 9p
Preferred ambient temperature (Ta) and ventilatory frequency were measured in free-moving hamsters exposed to 2450 MHz microwaves. A waveguide exposure system which permits continuous monitoring of the absorbed heat load accrued from microwave exposure was imposed with a longitudinal temperature gradient which allowed hamsters to select their preferred Ta. Ventilatory frequency was monitored remotely by analysing the rhythmic shifts in unabsorbed microwave energy passing down the waveguide. Without microwave exposure hamsters selected an average T2 of 30.2 C. This preferred Ta did not change until the rate of heat absorption (SAR) from microwave exposure exceeded approx. 2 W kg-1. In a separate experiment, a SAR of 2.0 W kg-1 at a Ta of 30C was shown to promote an average 0.5 C increase in colonic temperature. Hamsters maintained their ventilatory frequency at baseline levels by selecting a cooler Ta during microwave exposure. These data support previous studies suggesting that during thermal stress behavioral thermo-regulation (i.e. preferred Ta) takes prescedence over autonomic thermoregulation (i.e. ventilatory frequency). It is apparent that selecting a cooler Ta is a more efficient and/or effective than autonomic thermoregulation for dissipating a heat load accrued from microwave exposure.