Study type: Medical/biological study (experimental study)

The effect of electromagnetic fields emitted by mobile phones on human sleep. med./bio.

Published in: Neuroreport 2005; 16 (17): 1973-1976

Aim of study (acc. to author)

To test the effects of mobile phone radiofrequency electromagnetic field on human sleep patterns.

Background/further details

In order to simulate real-life exposure conditions and sleep habits, the present study exposed subjects to pulsed high-frequency electromagnetic field emitted by an actual mobile phone (with continuous transmission and constant power output, prior to a full night-time sleep episode).
Additionally, the authors attempted to replicate previous studies (see publication 9345 and publication 9849) and test the hypotheses that the 11.5-12.25, 12.25-13.5, and 13.5-14 Hz frequency bands would be enhanced following radiofrequency electromagnetic field exposure.

Endpoint

Exposure

Exposure Parameters
Exposure 1: 894.6 MHz
Modulation type: pulsed
Exposure duration: continuous for 30 min
  • SAR: 0.11 W/kg average over mass (10 g) (peak value of 0.29 W/kg)

Exposure 1

Main characteristics
Frequency 894.6 MHz
Type
Exposure duration continuous for 30 min
Modulation
Modulation type pulsed
Pulse width 576 µs
Duty cycle 12.5 %
Repetition frequency 217 Hz
Additional info

The 26th frame was not idle.

Exposure setup
Exposure source
Setup Participants sat comfortably in chairs with a mobile phone mounted in a cradle on the right side of the head in a normal use position with the antenna situated over the right temporal region. The GSM digital mobile phone was set to continuously transmit at constant power, using a link to a laptop computer.
Additional info The audio circuits of the phone were disconnected and padding was placed between the handset and its cover to prevent acoustic or thermal cues. Additionally, a white noise signal was used in the background in order to mask any residual sound from the handset's operation. Participants attended two sessions one week apart and were subject to randomized EMF or sham exposure using a double-blind crossover design.
Parameters
Measurand Value Type Method Mass Remarks
SAR 0.11 W/kg average over mass measured 10 g peak value of 0.29 W/kg

Exposed system:

Methods Endpoint/measurement parameters/methodology

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

Main outcome of study (acc. to author)

The data revealed a decrease in REM sleep latency and increased electroencephalogram spectral power in the 11.5-12.25 Hz frequency band range during the initial part of sleep following exposure. These findings are evidence that mobile phone exposure prior to sleep may promote REM sleep and modify the sleep electroencephalogram in the first non-REM sleep period. No conclusions can be made regarding adverse health consequences as the mechanisms of the effects are still unknown.

Study character:

Study funded by

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