Study type: Medical/biological study (experimental study, review/survey)

Increased blood-brain barrier permeability in mammalian brain 7 days after exposure to the radiation from a GSM-900 mobile phone. med./bio.

Published in: Pathophysiology 2009; 16 (2-3): 103-112

Aim of study (acc. to author)

To study the effects of GSM mobile phone irradiation upon the blood-brain barrier permeability of rats seven days after one occasion of 2 h of exposure and whether the same increase of the blood-brain barrier permeability is seen seven days after exposure as that showed immediately after exposure (see Persson et al. 1997) and after 14 days (see Eberhardt et al. 2008), and whether different exposure levels (SAR values) result in a different responses.
The first section of the article inculdes also a review of the literature on the effects (or lack of effects) of microwave exposure upon the blood-brain barrier.

Background/further details

48 rats were exposed at non-thermal specific absorption rates of 0 mW/kg (n=16), 0.12 mW/kg (n=8), 1.2 mW/kg (n=8), 12 mW/kg (n=8) and 120 mW/kg (n=8).

Endpoint

Exposure

Exposure Parameters
Exposure 1: 915 MHz
Modulation type: pulsed
Exposure duration: continuous for 2 hr
  • power: 1 mW peak value
  • power: 10 mW peak value
  • power: 100 mW peak value
  • power: 1,000 mW peak value
  • SAR: 0.12 mW/kg average over mass (whole body)
  • SAR: 1.2 mW/kg average over mass (whole body)
  • SAR: 12 mW/kg average over mass (whole body)
  • SAR: 120 mW/kg average over mass (whole body)

Exposure 1

Main characteristics
Frequency 915 MHz
Type
Exposure duration continuous for 2 hr
Modulation
Modulation type pulsed
Exposure setup
Exposure source
Setup GSM mobile phone connected via a coaxial cable to the TEM cell; TEM cell cenclosed in a 15 cm x 15 cm x 15 cm wooden box that supports the outer brass net conductor and the central conducting plate; rats placed in 14 cm x 14 cm x 7 cm plastic tray in the TEM cell
Sham exposure A sham exposure was conducted.
Parameters
Measurand Value Type Method Mass Remarks
power 1 mW peak value - - -
power 10 mW peak value - - -
power 100 mW peak value - - -
power 1,000 mW peak value - - -
SAR 0.12 mW/kg average over mass - whole body -
SAR 1.2 mW/kg average over mass - whole body -
SAR 12 mW/kg average over mass - whole body -
SAR 120 mW/kg average over mass - whole body -

Reference articles

  • 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.
  • Salford LG et al. (2008): The mammalian brain in the electromagnetic fields designed by man with special reference to blood-brain barrier function, neuronal damage and possible physical mechanisms.
  • Nittby H et al. (2008): Cognitive impairment in rats after long-term exposure to GSM-900 mobile phone radiation.
  • Salford LG et al. (2007): Non-thermal effects of EMF upon the mammalian brain: the Lund experience.
  • Belyaev IY et al. (2006): Exposure of rat brain to 915 MHz GSM microwaves induces changes in gene expression but not double stranded DNA breaks or effects on chromatin conformation.
  • Persson BRR et al. (1997): Blood-brain barrier permeability in rats exposed to electromagnetic fields used in wireless communication.
  • 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.

Exposed system:

Methods Endpoint/measurement parameters/methodology

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

Main outcome of study (acc. to author)

Albumin extravasation was statistically significant increased in the mobile phone exposed rats as compared to sham exposed controls after this 7-day recovery period at the SAR value of 12 mW/kg and with a trend of enhanced albumin extravasation also at the SAR values of 0.12 mW/kg and 120 mW/kg. There was a low, but significant correlation between the exposure level (SAR-value) and occurrence of focal albumin extravasation.
The data are in agreement with earlier studies of the authors (see above and "related articles") where they have seen increased permeability of blood-brain barrier immediately and 14 days after exposure.

Study character:

Study funded by

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