Study type: Medical/biological study (experimental study)

On the interdependence of thermal and electromagnetic effects in the response of Bacillus subtilis spores to microwave exposure med./bio.

By: Wayland JR, Brannen JP, Morris ME
Published in: Radiat Res 1977; 71 (1): 251-258
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Aim of study (acc. to author)

To distinguish between thermal and electromagnetic effects on the inactivation rate of Bacillus subtilis spores. Microwave exposure was compared to conventional oven heating.

Endpoint

Exposure

Exposure Parameters
Exposure 1: 2.45 GHz
Modulation type: CW
Exposure duration: up to 300 min

Exposure 1

Main characteristics
Frequency 2.45 GHz
Type
Exposure duration up to 300 min
Additional info +- 50 MHz
Modulation
Modulation type CW
Exposure setup
Exposure source
Setup waveguide in TE10-mode; end of test tube positioned in the center of the waveguide
Parameters
Measurand Value Type Method Mass Remarks
power 30 kW maximum measured - -
electric field strength 1,310 V/cm maximum measured - 718 V/m - 1310 V/m

Exposed system:

Methods Endpoint/measurement parameters/methodology

Investigated system:
Time of investigation:
  • after exposure

Main outcome of study (acc. to author)

When comparing the inactivation rate with that obtained by exposure to heat alone, measurable differences were found. These differences are a clear indication of a nonthermal effect caused by microwave exposure.

Study character:

Study funded by