Study type: Medical/biological study (experimental study)

Electromagnetic fields, such as those from mobile phones, alter regional cerebral blood flow and sleep and waking EEG. med./bio.

Published in: J Sleep Res 2002; 11 (4): 289-295

Aim of study (acc. to author)

Two questions were adressed and investigated: (1) Does exposure to electromagnetic fields modify waking regional cerebral blood flow (rCBF)?, (2) Is pulse modulation of the signal critical for the EEG effect?

Endpoint

Exposure

Exposure Parameters
Exposure 1: 900 MHz
Modulation type: pulsed
Exposure duration: continuous for 30 min
  • SAR: 1 W/kg maximum (10 g)
Exposure 2: 900 MHz
Modulation type: CW
Exposure duration: continuous for 30 min
  • SAR: 1 W/kg maximum (10 g)

Exposure 1

Main characteristics
Frequency 900 MHz
Type
Exposure duration continuous for 30 min
Modulation
Modulation type pulsed
Duty cycle 12.5 %
Repetition frequency 217 Hz
Additional info

A 'handset-like' signal was used as emitted by GSM mobile phones with modulation components at 2, 8, 217, 1736 Hz.

Exposure setup
Exposure source
Setup Subjects sat on a chair with their heads between two plates to ensure a well-defined position with respect to two planar antennas (see reference article). The left side of the head was exposed.
Additional info In one experiment the subjects were exposed to pulse modulated EMF or sham-exposed. In the other experiment the following three exposure conditions were used: pulse modulated EMF, continuous wave EMF, or sham control. In both experiments a double-blind crossover design was used, and intervals between exposures were at least 1 week.
Parameters
Measurand Value Type Method Mass Remarks
SAR 1 W/kg maximum measured and calculated 10 g -

Exposure 2

Main characteristics
Frequency 900 MHz
Type
Exposure duration continuous for 30 min
Modulation
Modulation type CW
Exposure setup
Exposure source
Parameters
Measurand Value Type Method Mass Remarks
SAR 1 W/kg maximum measured and calculated 10 g -

Reference articles

Exposed system:

Methods Endpoint/measurement parameters/methodology

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

Main outcome of study (acc. to author)

(1) Pulse-modulated electromagnetic fields (EMF) alters waking rCBF and (2) pulse modulation of EMF is necessary to induce waking and sleep EEG-changes.

Study character:

Study funded by

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