Study type: Medical/biological study (experimental study)

No effect of TETRA hand portable transmission signals on human cognitive function and symptoms. med./bio.

Published in: Bioelectromagnetics 2010; 31 (3): 191-199

Aim of study (acc. to author)

To employ a standard exposure system to emulate the TETRA radiofrequency fields in a controlled environment, and to study whether brief TETRA radiofrequency exposure is capable of producing acute effects on cognitive performance.

Background/further details

53 male volunteers participated. Exposure and sham exposure sessions were performed on separate days at about the same time each day.

Endpoint

Exposure

Exposure Parameters
Exposure 1: 420 MHz
Exposure duration: 45 min in 1 min sequences of 54 s on - 6 s off
  • SAR: 2 W/kg peak value (10 g)

Exposure 1

Main characteristics
Frequency 420 MHz
Type
Exposure duration 45 min in 1 min sequences of 54 s on - 6 s off
Exposure setup
Exposure source
Chamber 33.4 m³ aluminum chamber, covered on the inside with RF absorbers, all non-coaxial cables to and from the chamber filtered at the entrance, ferrite beads mounted on the cables to suppress common signals, no 50 Hz power supply in the chamber, all lights were fibre optic or 12 V DC
Setup participants seated at a desk inside the chamber; tetra handset connected via a coaxial cable from the external antenna to a controllable attenuator, an amplifier, a coupler for monitoring the exposure, and to the exposure antenna fixed on a plastic helmet which the test person was wearing; antenna fixed in the cheek position
Sham exposure A sham exposure was conducted.
Parameters
Measurand Value Type Method Mass Remarks
SAR 2 W/kg peak value measured 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)

No statistically significant differences between the TETRA and sham exposure conditions were found for either trail making test or any of the other cognitive tasks or symptoms. In conclusion, the authors found no evidence that brief exposure to hand-held TETRA transmitters affects human cognitive function or subjective symptoms.

Study character:

Study funded by

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