Study type: Medical/biological study (experimental study)

Neurophysiologic effects at low level 1.8 GHz radiofrequency field exposure: a multiparametric approach on freely moving rats. med./bio.

Published in: Pathol Biol (Paris) 2007; 55 (3-4): 134-142

Aim of study (acc. to author)

This in vivo study was performed to get insight into cholinergic system of central nervous system in rats exposed to a 1.8 GHz (GSM) radiofrequency field. A neurochemical, electrophysiological and physiological approach was used.

Background/further details

36 male rats were exposed to two power density levels (1. ICNIRP public safety standard, and 2. a fraction of this standard) and examined one, two, and three days after exposure.

Endpoint

Exposure

Exposure Parameters
Exposure 1: 1.8 GHz
Modulation type: pulsed
Exposure duration: continuous for 24 h
  • power density: 1.2 W/m² unspecified
  • SAR: 0.048 W/kg mean (whole body) (± 0.012 W/kg)
  • SAR: 0.071 W/kg mean (unspecified) (± 0.032 W/kg; at the head level)
Exposure 2: 1.8 GHz
Modulation type: pulsed
Exposure duration: continuous for 24 h
  • power density: 9 W/m² unspecified
  • SAR: 0.36 W/kg mean (whole body) (± 0.09 W/kg)
  • SAR: 0.53 W/kg mean (unspecified) (± 0.24 W/kg; at the head level)

Exposure 1

Main characteristics
Frequency 1.8 GHz
Type
Charakteristic
Exposure duration continuous for 24 h
Modulation
Modulation type pulsed
Duty cycle 12.5 %
Repetition frequency 217 Hz
Exposure setup
Exposure source
Distance between exposed object and exposure source 1.65 m
Setup The animals were exposed to plane wave microwaves in a Plexiglas cage (30 x 30 x 30 cm) where they moved freely.
Sham exposure A sham exposure was conducted.
Parameters
Measurand Value Type Method Mass Remarks
power density 1.2 W/m² unspecified measured - -
SAR 0.048 W/kg mean calculated whole body ± 0.012 W/kg
SAR 0.071 W/kg mean calculated unspecified ± 0.032 W/kg; at the head level

Exposure 2

Main characteristics
Frequency 1.8 GHz
Type
Charakteristic
Exposure duration continuous for 24 h
Modulation
Modulation type pulsed
Duty cycle 12.5 %
Repetition frequency 217 Hz
Exposure setup
Exposure source
Parameters
Measurand Value Type Method Mass Remarks
power density 9 W/m² unspecified measured - -
SAR 0.36 W/kg mean calculated whole body ± 0.09 W/kg
SAR 0.53 W/kg mean calculated unspecified ± 0.24 W/kg; at the head level

Exposed system:

Methods Endpoint/measurement parameters/methodology

Investigated system:
Investigated organ system:
Time of investigation:
  • after exposure

Main outcome of study (acc. to author)

No significant difference in behavioral observations, subcutaneous temperature and EEG were found between exposed groups and control group.
Acetylcholine release in hippocampus and cholesterol-NMR spectra also failed to show any statistically significant effect of radiofrequency exposure compared to control group.
The observed lack of increase in time spent in REM sleep on the third day revealed significant difference between the exposure group (at 1.2 W/m2 power density) and control group regarding sleeping stage.
As a conclusion these results show no effect of radiofrequency exposure both on the cholinergic system and lipid metabolism of the rat brain.

Study character:

Study funded by

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