Study type: Medical/biological study (experimental study)

Abnormal cardiovascular responses induced by localized high power microwave exposure med./bio.

By: Lu ST, Brown DO, Johnson CE, Mathur SP, Elson EC
Published in: IEEE Trans Biomed Eng 1992; 39 (5): 484-492
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Aim of study (acc. to author)

In this study, heart rate, mean arterial pressure, pulse pressure, and respiration rate of thirty-six male rats (Sprague-Dawley; 10-12 weeks of age) exposed to microwaves of different power were investigated.

Endpoint

Exposure

Exposure Parameters
Exposure 1: 1.25 GHz
Modulation type: CW
Exposure duration: continuous for 5 min
Exposure 2: 1.25 GHz
Modulation type: pulsed
Exposure duration: continuous for 5 min
Exposure 3: 1.25 GHz
Modulation type: pulsed
Exposure duration: continuous for 5 min

Exposure 1

Main characteristics
Frequency 1.25 GHz
Type
Charakteristic
  • guided field
Exposure duration continuous for 5 min
Modulation
Modulation type CW
Exposure setup
Exposure source
Setup Ventral head-neck exposures were performed in an L-band (WR650) waveguide exposure system by inserting the head of the anaesthetised rat through the metal tube in the broadwall of the waveguide with the major axis of the rat parallel to E-polarisation in TE10 mode.
Sham exposure A sham exposure was conducted.
Parameters
Measurand Value Type Method Mass Remarks
power 2 W mean measured - -
power 6.4 W mean measured - -
Additional parameter details

The averaged SAR was 4.75 ± 1.87 W/kg per W in the brain and 17.15 ± 5.98 W/kg per W in the neck.

Measurement and calculation details

Dosimetry was performed by the thermometric method at 86 W CW by inserting seven fluoroptic thermal sensors into fresh rat carcasses.

Exposure 2

Main characteristics
Frequency 1.25 GHz
Type
Charakteristic
  • guided field
Exposure duration continuous for 5 min
Modulation
Modulation type pulsed
Pulse width 10 µs
Repetition frequency 0.5 Hz
Exposure setup
Exposure source
Parameters
Measurand Value Type Method Mass Remarks
power 400 kW peak value measured - -
power 2 W mean measured - -

Exposure 3

Main characteristics
Frequency 1.25 GHz
Type
Charakteristic
  • guided field
Exposure duration continuous for 5 min
Modulation
Modulation type pulsed
Pulse width 1 µs
Repetition frequency 16 Hz
Exposure setup
Exposure source
Parameters
Measurand Value Type Method Mass Remarks
power 400 kW peak value measured - -
power 6.4 W mean measured - -

Exposed system:

Methods Endpoint/measurement parameters/methodology

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

Main outcome of study (acc. to author)

Respiration rate and mean arterial pressure were not altered. Changes in heart rate and pulse pressure were observed in rats exposed to higher power but not to the lower average power microwaves.

Study character:

Study funded by