Study type: Medical/biological study (experimental study)

Effect of millimeter waves on survival of UVC-exposed Escherichia coli. med./bio.

Published in: Bioelectromagnetics 1995; 16 (3): 188-196

Aim of study (acc. to author)

To investigate the survival of E. coli exposed to mm waves with and without an additional exposure of bacteria to UV light.

Endpoint

Exposure

Exposure Parameters
Exposure 1: 61 GHz
Modulation type: CW
Exposure duration: 5, 10, 15, 20, 25, 30 min

Exposure 1

Main characteristics
Frequency 61 GHz
Type
Waveform
Charakteristic
Exposure duration 5, 10, 15, 20, 25, 30 min
Additional info 61 +- 2,1 GHz
Modulation
Modulation type CW
Exposure setup
Exposure source
Distance between exposed object and exposure source 0.007 m
Parameters
Measurand Value Type Method Mass Remarks
power density 10 W/m² - - - at distance of 7 mm (+/- 1 mm)
SAR 84 W/kg - calculated - -

Exposed system:

Methods Endpoint/measurement parameters/methodology

Investigated system:
Time of investigation:
  • after exposure

Main outcome of study (acc. to author)

The exposure alone under these experimental conditions did not change the survival of E. coli, and the combined mm-wave + UVC treatment, when compared to UVC treatment, also failed to produce any change. Only when mm waves were applied after UVC irradiation, survival of the bacteria increased to a maximum value of over 30% after 25 min of mm-wave exposure (compared to the sham-exposed bacteria).
The authors suggest that some direct or indirect action of millimeter waves on different DNA repair systems of E. coli was responsible for the increased bacterial survival rate.

Study character:

Study funded by

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