Study type: Medical/biological study (experimental study)

Biomarkers in volunteers exposed to mobile phone radiation. med./bio.

Published in: Toxicol Lett 2015; 235 (2): 140-146

Aim of study (acc. to author)

The effects of exposure to a 890 MHz electromagnetic field (GSM) on the human blood brain barrier permeability should be investigated.

Background/further details

The present study should follow up on previous studies by the authors on the human blood brain barrier permeability (Söderqvist et al. 2009a, Söderqvist et al. 2009b, Söderqvist et al. 2009c) using a better study design.
A total of 24 subjects (12 men and 12 women) participated in 3 sessions with at least one week in between. During each session, 1 hour of exposure was conducted in a randomized counter balanced order under the following conditions: 1) exposure with SAR of 2 W/kg, 2) exposure with SAR of 0.2 W/kg, 3) sham exposure. Each participant acted as his or her own control and blood samples were taken: a) at arrival, b) after 30 min of rest, c) after 1 h of rest/start of exposure, d) immediately after exposure, e) 1 h after the end exposure; f) 2 h after the end of exposure.

Endpoint

Exposure

Exposure Parameters
Exposure 1: 890 MHz
Modulation type: pulsed
Exposure duration: continuous for 1 hour
  • SAR: 2 W/kg average over mass (10 g)
Exposure 2: 890 MHz
Modulation type: pulsed
Exposure duration: continuous for 1 hour
  • SAR: 0.2 W/kg average over mass (10 g)

Exposure 1

Main characteristics
Frequency 890 MHz
Type
Exposure duration continuous for 1 hour
Modulation
Modulation type pulsed
Pulse width 0.577 ms
Repetition frequency 217 Hz
Additional info

signal from GSM test phone; no DTX was used

Exposure setup
Exposure source
Distance between exposed object and exposure source 4 cm
Chamber room was shielded by a specially made baldachin (250 x 210 x 230 cm); inside, special radiofrequency-absorbing material (eccosorb) was mounted to avoid reflection of waves
Setup the signal from a GSM test phone (Ericsson GH 337) was fed to an indoor base station antenna; two identical antennas were used, one mounted on each side of the participant's head at a distance of 4 cm from the ear, but only the right antenna was used; subjects were seated in a reclining chair in front of a LCD computer screen to watch a DVD during the session
Sham exposure A sham exposure was conducted.
Additional info trials were carried out in a room with low-frequency electric, magnetic and radiofrequency background fields low enough to be considered negligible
Parameters
Measurand Value Type Method Mass Remarks
SAR 2 W/kg average over mass - 10 g -

Exposure 2

Main characteristics
Frequency 890 MHz
Type
Exposure duration continuous for 1 hour
Modulation
Modulation type pulsed
Pulse width 0.577 ms
Repetition frequency 217 Hz
Additional info

signal from GSM test phone; no DTX was used

Exposure setup
Exposure source
Distance between exposed object and exposure source 4 cm
Parameters
Measurand Value Type Method Mass Remarks
SAR 0.2 W/kg average over mass - 10 g -

Exposed system:

Methods Endpoint/measurement parameters/methodology

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

Main outcome of study (acc. to author)

Statistically significant changes in transthyretin and beta-trace protein levels were found over the course of time in each exposure condition (SAR of 2 W/kg, 0.2 W/kg and sham exposure). However, no significant differences were found between exposure conditions with and without regard to the time of blood sampling.
The authors conclude that exposure to a 890 MHz electromagnetic field (GSM) did not show any effects on the human blood brain barrier permeability.

Study character:

Study funded by

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