Study type: Medical/biological study (experimental study)

Do signals of a hand-held TETRA transmitter affect cognitive performance, well-being, mood or somatic complaints in healthy young men? Results of a randomized double-blind cross-over provocation study. med./bio.

Published in: Environ Res 2015; 140: 85-94

Aim of study (acc. to author)

The effects of exposure of young men to a 385 MHz electromagnetic field (TETRA) on cognitive functions and well-being should be investigated.

Background/further details

30 young and healthy male volunteers were tested on nine study days, on which they were exposed to three different exposure conditions: 1) exposure to TETRA electromagnetic field with an SAR of 1.5 W/kg, 2) exposure to a TETRA field with 6 W/kg or 3) sham exposure.

Endpoint

Exposure

Exposure Parameters
Exposure 1: 385 MHz
Modulation type: pulsed
Exposure duration: continuous for 2.5 hours
  • SAR: 1.5 W/kg maximum (10 g)
Exposure 2: 385 MHz
Modulation type: pulsed
Exposure duration: continuous for 2.5 hours
  • SAR: 6 W/kg maximum (10 g)

General information

antenna and TETRA signal were designed to simulate actual exposure of a TETRA hand-set; radio frequency background fields (broadband 100 kHz to 3 GHz) in the shielded exposure room were below 0.2 V/m, and low frequency electric and magnetic fields from power lines (50 Hz) were 2.1 V/m and max. 320 nT

Exposure 1

Main characteristics
Frequency 385 MHz
Type
Exposure duration continuous for 2.5 hours
Modulation
Modulation type pulsed
Pulse width 14.17 ms
Duty cycle 25 %
Repetition frequency 17.65 Hz
Exposure setup
Exposure source
Chamber shielded room
Setup participants wore a cushioned light weight antenna on the left side of their heads (maximum exposure in the temporal region) and were not able to perceive differences in warming
Sham exposure A sham exposure was conducted.
Parameters
Measurand Value Type Method Mass Remarks
SAR 1.5 W/kg maximum measured and calculated 10 g -

Exposure 2

Main characteristics
Frequency 385 MHz
Type
Exposure duration continuous for 2.5 hours
Modulation
Modulation type pulsed
Pulse width 14.17 ms
Duty cycle 25 %
Repetition frequency 17.65 Hz
Exposure setup
Exposure source
Parameters
Measurand Value Type Method Mass Remarks
SAR 6 W/kg maximum measured and calculated 10 g -

Reference articles

  • Dorn H et al. (2014): Experimental investigation of possible warmth perception from a head exposure system for human provocation studies with TETRA handset-like signals.
  • Schmid G et al. (2012): Design and dosimetric analysis of a 385 MHz TETRA head exposure system for use in human provocation studies.

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)

The mood and well-being were not impaired in both exposure groups compared to the sham exposure group and there were no subjective complaints.
In the working memory tests, group 2 (SAR 6 W/kg) showed a significantly lower number of correct reactions in the 1-back task compared to group 1 and the sham exposure group. In the 2-back task, the reaction time was significantly enhanced in both exposure groups compared to the sham exposure group.
The authors conclude that the results give no indications for negative effects of exposure of young men to a 385 MHz electromagnetic field (TETRA) on cognitive functions or well-being.

Study character:

Study funded by

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