Study type: Medical/biological study (experimental study)

Effects of mobile phone exposure (GSM 900 and WCDMA/UMTS) on polysomnography based sleep quality: An intra- and inter-individual perspective. med./bio.

Published in: Environ Res 2016; 145: 50-60

Aim of study (acc. to author)

The effects of nocturnal exposure of subjects to a GSM (900 MHz) or a WCDMA/UMTS (2 GHz) electromagnetic field on the sleep structure should be investigated.

Background/further details

30 healthy young men (18-30 years) participated in the study. Each subject was studied for a total of 10 nights, which were scheduled at an interval of approximately one night every two weeks. The first night served for adaptation and screening purposes, the remaining 9 nights were recorded. During these 9 nights, subjects were either exposed to GSM, WCDMA/UMTS or sham exposure for three nights each, following a randomized design.

Endpoint

Exposure

Exposure Parameters
Exposure 1: 900 MHz
Modulation type: pulsed
Exposure duration: continuous during the whole night (recording for 8 h) for a total of 3 nights
GSM
  • SAR: 2 W/kg maximum (10 g)
Exposure 2: 1,966 MHz
Exposure duration: continuous during the whole night (recording for 8 h) for a total of 3 nights
  • SAR: 2 W/kg maximum (10 g)

Exposure 1

Main characteristics
Frequency 900 MHz
Type
Exposure duration continuous during the whole night (recording for 8 h) for a total of 3 nights
Additional info GSM
Modulation
Modulation type pulsed
Duty cycle 12.5 %
Repetition frequency 217 Hz
Exposure setup
Exposure source
Chamber shielded room
Setup a head-worn antenna with textile cushion fed by a thin RF coaxial cable was used and attached to the right side of the head during sleep; only RF immune devices were used in the exposure room, other equipment like clocks, portable players and phones were not allowed
Sham exposure A sham exposure was conducted.
Parameters
Measurand Value Type Method Mass Remarks
SAR 2 W/kg maximum measured and calculated 10 g -

Exposure 2

Main characteristics
Frequency 1,966 MHz
Type
Exposure duration continuous during the whole night (recording for 8 h) for a total of 3 nights
Additional info WCDMA/UMTS
Modulation
Modulation type cf. additional info
Additional info

1966 MHz carrier frequency with Quadrature Phase Shift Keying (QPSK) modulation and a power control emulation sequence repeated every minute; the sequence comprised 45 s of toggling between 50% and 100% maximum output power for 0.67 ms each and 15 s of simulated fading over a dynamic range of 30 dB

Exposure setup
Exposure source
Parameters
Measurand Value Type Method Mass Remarks
SAR 2 W/kg maximum measured and calculated 10 g -

Reference articles

Exposed system:

Methods Endpoint/measurement parameters/methodology

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

Main outcome of study (acc. to author)

In 90% of the subjects, one or more sleep parameters were significantly different during exposure to GSM or WCDMA/UMTS fields compared to the sham exposure condition. However, effects showed no consistence between individuals except for an increased REM sleep duration (9 subjects during GSM exposure, 10 subjects during WCDMA/UMTS exposure).
The authors conclude that exposure of subjects to a GSM (900 MHz) or a WCDMA/UMTS (2 GHz) electromagnetic field might induce individual changes in the sleep structure and a general prolongation of the REM sleep phase. These changes do not necessarily indicate a disturbance of sleep.

Study character:

Study funded by

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