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.

By: Crouzier D, Debouzy JC, Bourbon F, Collin A, Perrin A, Testylier G

Published in: Pathol Biol 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

effects on the neurological system: effects on cholinergic system

Exposure

- microwaves
- mobile communications
- digital mobile phone
- GSM

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	electromagnetic field
Charakteristic	far field
Exposure duration	continuous for 24 h

Modulation

Modulation type	pulsed
Duty cycle	12.5 %
Repetition frequency	217 Hz

Exposure setup

Exposure source	horn antenna anechoic chamber 18 x 23 cm
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

Measurement and calculation details

The power density was determined using an anisotropic field meter. The SAR distribution in the rat body was determined using the FDTD method. Mean SAR was determined using several positions of the rat.

Exposure 2

Main characteristics

Frequency	1.8 GHz
Type	electromagnetic field
Charakteristic	far field
Exposure duration	continuous for 24 h

Modulation

Modulation type	pulsed
Duty cycle	12.5 %
Repetition frequency	217 Hz

Exposure setup

Exposure source	same setup as exposure 1

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

effects on the neurological system: acetylcholine release in hippocampus (microdialysis, HPLC; EEG), lipid metabolism (¹³cholesterol-NMR spectra)
cognitive/behavioral endpoints: behaviour (locomotion, feeding and grooming activity)
thermoregulation: subcutaneous temperature
sleep: sleep stages (EEG)

Investigated system:

investigation on living organism

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:

medical/biological study
experimental study
full/main study

Study funded by

Délégation Générale pour l'Armement (DGA; part of Ministère de la Défense (Ministry of Defense)), France

Khirazova EE et al. (2012): Effects of GSM-Frequency Electromagnetic Radiation on Some Physiological and Biochemical Parameters in Rats
Ammari M et al. (2010): GFAP expression in the rat brain following sub-chronic exposure to a 900 MHz electromagnetic field signal
Kim TH et al. (2008): Local exposure of 849 MHz and 1763 MHz radiofrequency radiation to mouse heads does not induce cell death or cell proliferation in brain
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Mausset AL et al. (2001): Effects of radiofrequency exposure on the GABAergic system in the rat cerebellum: clues from semi-quantitative immunohistochemistry
Lai H et al. (1989): Low-level microwave irradiation and central cholinergic activity: a dose-response study
Lai H et al. (1988): Acute low-level microwave exposure and central cholinergic activity: studies on irradiation parameters
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Lai H et al. (1987): Effects of low-level microwave irradiation on hippocampal and frontal cortical choline uptake are classically conditionable
Modak AT et al. (1981): Effect of short electromagnetic pulses on brain acetylcholine content and spontaneous motor activity of mice

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

Aim of study (acc. to author)

Background/further details

Endpoint

Exposure

Exposure 1

Main characteristics

Modulation

Exposure setup

Parameters

Measurement and calculation details

Exposure 2

Main characteristics

Modulation

Exposure setup

Parameters

Methods Endpoint/measurement parameters/methodology

Main outcome of study (acc. to author)

Study funded by

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