EMF-Portal | Comparison of bacterial growth to high-intensity microwave exposure and conventional heating

Comparison of bacterial growth to high-intensity microwave exposure and conventional heating med./bio.

Aim of study (acc. to author)

Endpoint

Exposure

Exposure	Parameters
Exposure 1: 8.8 GHz Modulation type: pulsed Exposure duration: continuous for 2, 5, 10, or 15 h	power density: 20 mW/cm² mean SAR: 40 W/kg

Exposure source	horn antenna anechoic chamber 10 dB, magnetron
Distance between exposed object and exposure source	50 cm
Chamber	Two foamed polystyrene chambers were supplied with the same temperature-controlled air (35.2 °C), one for exposure in the anechoic room and the other one for control.
Setup	Cell suspensions (3 ml, about 3 mm thick) were placed in 35-mm plastic Petri dishes sealed in Saran wrap and exposed from above.
Additional info	For conventional heating, samples were incubated at 42.2 °C for 0, 2, 5, 10, and 15 h. Control samples were also incubated at 35.2 °C for up to 15 h.

Measurand	Value	Type	Method	Mass	Remarks
power density	20 mW/cm²	mean	-	-	-
SAR	40 W/kg	-	measured	-	-

SAR was determined according to the method described by Allis et al. [1977].

Allis JW et al. (1977): Measurement of microwave radiation absorbed by biological systems, 1. Analysis of heating and cooling data

Exposed system:

Methods Endpoint/measurement parameters/methodology

Investigated system:

Time of investigation:

Main outcome of study (acc. to author)

8.8 GHz pulsed microwave radiation has no effect on the growth of E. coli beyond that associated with temperature increase.

Study character:

Study funded by

Environmental Protection Agency (EPA), USA

National Institutes of Health (NIH), Maryland, USA

Shamis Y et al. (2011): Specific electromagnetic effects of microwave radiation on Escherichia coli

Comparison of bacterial growth to high-intensity microwave exposure and conventional heating med./bio.