Study type: Medical/biological study (experimental study)

Stress proteins are not induced in mammalian cells exposed to radiofrequency or microwave radiation med./bio.

By: Cleary SF, Cao G, Liu LM, Egle PM, Shelton KR
Published in: Bioelectromagnetics 1997; 18 (7): 499-505
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Aim of study (acc. to author)

To test the hypothesis that stress proteins are induced by exposure of mammalian cells to radiofrequency under conditions known to cause physiological changes in cells.

Endpoint

Exposure

Exposure Parameters
Exposure 1: 27 MHz
Modulation type: CW
Exposure duration: continuous for 2 h
Exposure 2: 2,450 MHz
Modulation type: CW
Exposure duration: continuous for 2 h

Exposure 1

Main characteristics
Frequency 27 MHz
Type
Charakteristic
  • guided field
Exposure duration continuous for 2 h
Modulation
Modulation type CW
Exposure setup
Exposure source
  • coaxial line exposure system [Guy, 1977]
Chamber Cell suspensions were RF or sham exposed under isothermal conditions (37 ± 0.2 °C).
Sham exposure A sham exposure was conducted.
Additional info Parallel positive control studies included 2 h exposure of cells to 40 °C or to 45 µM cadmium sulphate.
Parameters
Measurand Value Type Method Mass Remarks
SAR 25 W/kg - - - HeLa cells
SAR 100 W/kg - - - CHO cells
Measurement and calculation details

Temperature control precision, dosimetry, and microwave densitometry of this in vitro exposure system have been described in [Guy, 1977] and [Cleary et al., 1985].

Exposure 2

Main characteristics
Frequency 2,450 MHz
Type
Charakteristic
  • guided field
Exposure duration continuous for 2 h
Modulation
Modulation type CW
Exposure setup
Exposure source
Sham exposure A sham exposure was conducted.
Parameters
Measurand Value Type Method Mass Remarks
SAR 25 W/kg - - - HeLa cells
Measurement and calculation details

Temperature control precision, dosimetry, and microwave densitometry of this in vitro exposure system have been described in [Galvin et al., 1980] and [Liu and Cleary, 1988].

Reference articles

  • Liu LM et al. (1988): Effects of 2.45-GHz microwave and 100-MHz radiofrequency radiation on liposome permeability at the phase transition temperature
  • Cleary SF et al. (1985): Erythrocyte hemolysis by radiofrequency fields
  • Galvin MJ et al. (1980): Microwave irradiation and in vitro release of enzymes from hepatic lysosomes
  • Guy AW (1977): A method for exposing cell cultures to electromagnetic fields under controlled conditions of temperature and field strength

Exposed system:

Methods Endpoint/measurement parameters/methodology

Investigated system:
Time of investigation:
  • after exposure

Main outcome of study (acc. to author)

The results indicate that under the given conditions, neither microwave nor radiofrequency radiation had a detectable effect on stress protein induction as determined by either comparison of radiofrequency-exposed cells with sham-exposed cells or comparison with heat stressed or Cd++ positive control.

Study character:

Study funded by

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