Study type: Medical/biological study (experimental study)

Effects of isothermal 2.45 GHz microwave radiation on the mammalian cell cycle: comparison with effects of isothermal 27 MHz radiofrequency radiation exposure. med./bio.

Published in: Bioelectrochem Bioenerg 1996; 39 (2): 167-173

Aim of study (acc. to author)

Synchronized cells were exposed to continuous wave (CW) 2.45 GHz microwave irradiation or CW 27 MHz radiofrequency irradiation under isothermal conditions (37 ± 0.2 °C) to test the following hypotheses: (1) high frequency electromagnetic irradiation directly affects the mammalian cell cycle in the absence of irradiation-induced heating; and (2) the magnitude of the cell cycle alteration is frequency dependent.

Endpoint

Exposure

Exposure Parameters
Exposure 1: 2.45 GHz
Modulation type: CW
Exposure duration: continuous for 2 h
Exposure 2: 27 MHz
Modulation type: CW
Exposure duration: continuous for 2 h

General information

Cell suspensions were simultaneously exposed to 2.45 and 27 MHz RF radiation at SARs of 0, 5, or 25 W/kg.

Exposure 1

Main characteristics
Frequency 2.45 GHz
Type
Charakteristic
  • guided field
Exposure duration continuous for 2 h
Modulation
Modulation type CW
Exposure setup
Exposure source
Chamber Temperature was maintained at 37°C by coolant circulation from controlled baths.
Sham exposure A sham exposure was conducted.
Parameters
Measurand Value Type Method Mass Remarks
SAR 5 W/kg - - - -
SAR 25 W/kg - - - -

Exposure 2

Main characteristics
Frequency 27 MHz
Type
Charakteristic
  • guided field
Exposure duration continuous for 2 h
Modulation
Modulation type CW
Exposure setup
Exposure source
Setup The coaxial transmission line tapered up to inner and outer stainless steel conductors of 3.34 and 3.84 cm radius provided an annular exposure chamber. The use of this system, including dosimetric methods, has been described by Cleary et al. [1985] and Liu and Cleary [1988].
Sham exposure A sham exposure was conducted.
Parameters
Measurand Value Type Method Mass Remarks
SAR 5 W/kg - - - -
SAR 25 W/kg - - - -

Reference articles

Exposed system:

Methods Endpoint/measurement parameters/methodology

Investigated system:
Time of investigation:
  • after exposure

Main outcome of study (acc. to author)

Exposure to 27 MHz radiofrequency irradiation or 2.45 GHz microwave irradiation altered the cell cycle for periods of up to 4 days following exposure at SARs of 5 or 25 W/kg. There were significant differences in temporal responses, cell cycle phase sensitivity, and overall degree of cell cycle alteration for 27 MHz in comparison to 2.45 GHz irradiation. In contrast to the effect of 27 MHz radiofrequency irradiation, which did not affect G2/M-phase cells, 2.45 GHz microwave irradiation altered all cell cycle phases to varying degrees. Exposure to 2.45 GHz at 5 or 25 W/kg was twice as effective as 27 MHz irradiation in inducing cell cycle alterations as determined by differences in the number of exposed versus sham-exposed cells in various cell cycle phases.

Study character:

Study funded by

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