Medical/biological study (experimental study)

Effects of head-only exposure of rats to GSM-900 on blood-brain barrier permeability and neuronal degeneration med./bio.

By: de Gannes FP, Billaudel B, Taxile M, Haro E, Ruffie G, Leveque P, Veyret B, Lagroye I

Published in: Radiat Res 2009; 172 (3): 359-367

Aim of study (acc. to editor)

The aim of this study was to perform a confirmation study of Salford et al. 2003 using well-controlled conditions (age and sex of animals, animal facility, restrainer habituation, exposure conditions) and thus to study the effects of radiofrequency exposure on the permeability of blood-brain barrier and on neuron degeneration.

Background/further details

Five groups of 16 rats were exposed to SAR values of 0, 0.14 and 2.0 W/kg. Cage control (n=8) and positive controls (subjected to cold shock to induce brain damage; n=10) were also performed.

Endpoint

effects on the neurological system: permeability of blood-brain barrier and neuron degeneration

Exposure

- mobile communications
- mobile phone
- digital mobile phone
- GSM

Exposure	Parameters
Exposure 1: 900 MHz Exposure duration: continuous for 2 hr	SAR: 0.14 W/kg average over mass (brain) SAR: 2 W/kg average over mass (brain)

Exposure 1

Main characteristics

Frequency	900 MHz
Type	electromagnetic field
Exposure duration	continuous for 2 hr

Exposure setup

Exposure source	TEM cell loop antenna
Setup	during exposure rats kept in a cylinder with a cone of Plexiglas
Sham exposure	A sham exposure was conducted.

Parameters

Measurand	Value	Type	Method	Mass	Remarks
SAR	0.14 W/kg	average over mass	-	brain	-
SAR	2 W/kg	average over mass	-	brain	-

Reference articles

Leveque P et al. (2004): Dosimetric Analysis of a 900-MHz Rat Head Exposure System

Exposed system:

animal
rat/Fischer 344
partial body: head

Methods Endpoint/measurement parameters/methodology

effects on the neurological system: permeability of blood-brain barrier (albumin leakage; immunohistochemistry); neuron degeneration/"dark neurons" (cresyl violet stain and Fluoro-Jade B stain (more specific than cresyl violet)); apoptotic neurons (TUNEL assay); (both 14 and 50 days after exposure)

Investigated system:

tissue slices

Investigated organ system:

brain/CNS

Time of investigation:

after exposure

Main outcome of study (acc. to author)

Exposure of rat brains at two SAR values induced no neuronal degeneration, permeability of blood-brain barrier or neuronal apoptosis. These data differ from those obtained by Salford et al. 2003 even at the higher SAR of 2 W/kg, i.e. ten times higher than the maximum used by the Swedish group.
The authors conclude that, under these exposure conditions, GSM-900 radiofrequency irradiation does not generate brain damage at levels up to the standard local exposure limit for the public.

Study character:

medical/biological study
experimental study
full/main study
blind study

Study funded by

Bouygues Telecom, France
Centre National de la Recherche Scientifique (CNRS; French National Center for Scientific Research), France
France Telecom

Soderqvist F et al. (2015): Biomarkers in volunteers exposed to mobile phone radiation
Tang J et al. (2015): Exposure to 900 MHz electromagnetic fields activates the mkp-1/ERK pathway and causes blood-brain barrier damage and cognitive impairment in rats
Sirav B et al. (2011): Effects of radiofrequency radiation exposure on blood-brain barrier permeability in male and female rats
Ait-Aissa S et al. (2010): In situ detection of gliosis and apoptosis in the brains of young rats exposed in utero to a Wi-Fi signal
Nittby H et al. (2009): Increased blood-brain barrier permeability in mammalian brain 7 days after exposure to the radiation from a GSM-900 mobile phone
Masuda H et al. (2009): Effects of 915 MHz electromagnetic-field radiation in TEM cell on the blood-brain barrier and neurons in the rat brain
Sirav B et al. (2009): Blood-brain barrier disruption by continuous-wave radio frequency radiation
McQuade JM et al. (2009): Radiofrequency-radiation exposure does not induce detectable leakage of albumin across the blood-brain barrier
Eberhardt JL et al. (2008): Blood-brain barrier permeability and nerve cell damage in rat brain 14 and 28 days after exposure to microwaves from GSM mobile phones
Grafstrom G et al. (2008): Histopathological examinations of rat brains after long-term exposure to GSM-900 mobile phone radiation
Masuda H et al. (2007): Effects of acute exposure to a 1439 MHz electromagnetic field on the microcirculatory parameters in rat brain
Masuda H et al. (2007): Effects of subchronic exposure to a 1439 MHz electromagnetic field on the microcirculatory parameters in rat brain
Finnie JW et al. (2006): Neonatal mouse brain exposure to mobile telephony and effect on blood-brain barrier permeability
Finnie JW et al. (2006): Effect of mobile telephony on blood-brain barrier permeability in the fetal mouse brain
Salford LG et al. (2003): Nerve cell damage in mammalian brain after exposure to microwaves from GSM mobile phones
Salford LG et al. (1994): Permeability of the blood-brain barrier induced by 915 MHz electromagnetic radiation, continuous wave and modulated at 8, 16, 50, and 200 Hz
Salford LG et al. (1993): Permeability of the blood-brain barrier induced by 915 MHz electromagnetic radiation, continuous wave and modulated at 8, 16, 50 and 200 Hz