Study type: Medical/biological study (experimental study)

Mobile phone headache: a double blind, sham-controlled provocation study. med./bio.

Published in: Cephalalgia 2007; 27 (5): 447-455

Aim of study (acc. to author)

To study whether exposure to radiofrequency electromagnetic fields from mobile phones would result in more headache or discomfort than sham exposure and to test possible effects on physiological parameters such as heart rate and blood pressure.

Background/further details

17 eligible individuals, who experienced symptoms (symptoms to mobile phones, but not to electromagnetic fields in general) in a provocation test, took part in the study.

Endpoint

Exposure

Exposure Parameters
Exposure 1: 902.4 MHz
Modulation type: pulsed
Exposure duration: continuous for 30 min
  • SAR: 1 W/kg cf. remarks (1 g) (spatial peak)
  • SAR: 0.8 W/kg average over mass (10 g)

General information

Seventeen subjects took part in a double-blind, randomized provocation study with cross-over design. Sixty-five pairs of sham and mobile phone RF exposures were applied. Each subject was allowed to take part in a maximum of four randomized pairs of trials, at least 2 days apart, among which, the RF session came first twice. A test session lasted almost 2 h, allowing for an adaptation and rest period.

Exposure 1

Main characteristics
Frequency 902.4 MHz
Type
Exposure duration continuous for 30 min
Modulation
Modulation type pulsed
Duty cycle 12.5 %
Repetition frequency 217 Hz
Exposure setup
Exposure source
Distance between exposed object and exposure source 8.5 cm
Chamber The exposure system was the same as in [Wilen et al., 2006]. The exposure equipment, except for the antennas, was placed in a control room next to the shielded exposure room. The subjects were comfortably seated while looking at videos showing nature and wildlife films.
Setup Two wall-mounted base station antennas [Huber et al., 2003] were mounted symmetrically at 8.5 cm from the sides of the subject's head, the movements of which were restricted sideways by wooden bars.
Sham exposure A sham exposure was conducted.
Additional info A power divider directed a part of the signal to one of the antennas or to an ohmic load (sham exposure) and another part to a power meter. The exposure was given on the subject's preferred side or selected by chance.
Parameters
Measurand Value Type Method Mass Remarks
SAR 1 W/kg cf. remarks - 1 g spatial peak
SAR 0.8 W/kg average over mass - 10 g -

Reference articles

  • Wilen J et al. (2006): Psychophysiological tests and provocation of subjects with mobile phone related symptoms.
  • Huber R et al. (2003): Radio frequency electromagnetic field exposure in humans: Estimation of SAR distribution in the brain, effects on sleep and heart rate.

Exposed system:

Methods Endpoint/measurement parameters/methodology

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

Main outcome of study (acc. to author)

The data gave no evidence that radiofrequency electromagnetic fields from mobile phones may cause headache or discomfort or influence physiological variables (heart rate, blood pressure).

Study character:

Study funded by

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