Study type: Medical/biological study (experimental study)

Ventilatory frequency of mouse and hamster during microwave-induced heat exposure. med./bio.

Published in: Respir Physiol 1984; 56 (1): 81-90

Aim of study (acc. to author)

To record ventilatory frequency as a function of microwave thermal load in mice and hamsters exposed to 2450 MHz microwaves at ambient temperatures of 10, 20 and 30°C.

Endpoint

Exposure

Exposure Parameters
Exposure 1: 2.45 GHz
Exposure duration: 60 min
  • SAR: 140 mW/g average over time (whole body) (maximum value)
Exposure 2: 2.45 GHz
Exposure duration: 60 min
  • SAR: 40 mW/g average over time (whole body) (maximum value)

Exposure 1

Main characteristics
Frequency 2.45 GHz
Charakteristic
  • guided field
Exposure duration 60 min
Modulation
Modulation type unspecified
Exposure setup
Exposure source
Setup Mice were exposed at Ta values of 10, 20 and 30°C.
Parameters
Measurand Value Type Method Mass Remarks
SAR 140 mW/g average over time measured whole body maximum value

Exposure 2

Main characteristics
Frequency 2.45 GHz
Charakteristic
  • guided field
Exposure duration 60 min
Modulation
Modulation type unspecified
Exposure setup
Exposure source
Setup Hamster were exposed at Ta values of 10, 20 and 30°C.
Parameters
Measurand Value Type Method Mass Remarks
SAR 40 mW/g average over time measured whole body maximum value

Exposed system:

Methods Endpoint/measurement parameters/methodology

Investigated system:
Investigated organ system:
Time of investigation:
  • during exposure

Main outcome of study (acc. to author)

In both species there was an inverse relationship between ambient temperature and threshold SAR to invoke an increase in breathing rate (ventilatory frequency). However, the threshold SARs for mice were 270 to 450% higher than for hamsters (depending on ambient temperature). On the basis of rate of absorbed energy normalized to body weight (W/kg), mice can tolerate much more heat from microwave irradiation than hamsters. The differences in sensitivity to microwave irradiation in the mouse and hamster are probably attributable to species-specific characteristics (especially differences in body mass and, consequently, passive heat loss).

Study character:

Study funded by