Study type: Medical/biological study (experimental study)

Ornithine decarboxylase activity is affected in primary astrocytes but not in secondary cell lines exposed to 872 MHz RF radiation. med./bio.

Published in: Int J Radiat Biol 2007; 83 (6): 367-374

Aim of study (acc. to author)

The study examined the effects of continuous wave or GSM modulated radiofrequency exposure on cellular ornithine decarboxylase enzyme activity in fibroblasts, two neural cell lines and primary astrocytes at higher exposure levels (SAR levels of 1.5, 2.5, and 6.0 W/kg) as in a previous study (publication 14027).

Background/further details

Medium change and serum deprivation was used as positive control.

Endpoint

Exposure

Exposure Parameters
Exposure 1: 872 MHz
Modulation type: pulsed
Exposure duration: continuous for 2, 8, or 24 h
Exposure 2: 872 MHz
Modulation type: CW
Exposure duration: continuous for 2, 8, or 24 h

Exposure 1

Main characteristics
Frequency 872 MHz
Type
Charakteristic
  • guided field
Exposure duration continuous for 2, 8, or 24 h
Modulation
Modulation type pulsed
Repetition frequency 217 Hz
Additional info

GSM

Exposure setup
Exposure source
Chamber Exposures were carried out in a temperature controlled waveguide exposure system described earlier together with dosimetric details [Hoyto et al., 2006].
Setup Approximately 20 h prior to exposure, cells were seeded into four 55-mm glass Petri dishes two of which were later placed in the exposure chamber and the other two in the sham-exposure chamber.
Sham exposure A sham exposure was conducted.
Additional info Some of the initial experiments were carried out with a slight temperature difference between the exposure and sham-exposure chambers (max. 0.8°C lower in the latter), due to an improperly functioning temperature sensor. Sham-sham experiments were carried out to check possible differences between the exposure chambers.
Parameters
Measurand Value Type Method Mass Remarks
SAR 1.5 W/kg - - - -
SAR 2.5 W/kg - - - -
SAR 6 W/kg - - - -

Exposure 2

Main characteristics
Frequency 872 MHz
Type
Charakteristic
  • guided field
Exposure duration continuous for 2, 8, or 24 h
Modulation
Modulation type CW
Exposure setup
Exposure source
Sham exposure A sham exposure was conducted.
Parameters
Measurand Value Type Method Mass Remarks
SAR 1.5 W/kg - - - -
SAR 2.5 W/kg - - - -
SAR 6 W/kg - - - -

Reference articles

  • Höytö A et al. (2006): Modest increase in temperature affects ODC activity in L929 cells: Low-level radiofrequency radiation does not.

Exposed system:

Methods Endpoint/measurement parameters/methodology

Investigated system:
Time of investigation:
  • after exposure

Main outcome of study (acc. to author)

Ornithine decarboxylase enzyme activity was significantly decreased by radiofrequency exposure in primary cells, but the secondary cells (cell lines) showed essentially no response to similar radiofrequency exposure. This is a very interesting result, because function of the primary cells is closer to normal tissues than that of secondary transformed cell lines. In contrast to some previous studies (see "related articles"), no differences between the modulated and continuous wave signals were found.

Study character:

Study funded by

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