Study type: Medical/biological study (experimental study)

Effects of a 902 MHz mobile phone on cerebral blood flow in humans: a PET study med./bio.

Published in: NeuroReport 2003; 14 (16): 2019-2023

Aim of study (acc. to author)

To study the effects of mobile phone on regional cerebral blood flow in human during exposure to electromagnetic field, while performing a working memory task.



Exposure Parameters
Exposure 1: 902 MHz
Modulation type: pulsed
Exposure duration: continuous for approx. 45 min
  • power: 0.25 W mean
  • SAR: 0.993 W/kg
  • SAR: 2 W/kg maximum (10 g) (extrapolated)

Exposure 1

Main characteristics
Frequency 902 MHz
Exposure duration continuous for approx. 45 min
Modulation type pulsed
Pulse width 0.577 ms
Repetition frequency 217 Hz
Additional info

Discontinuous transmission mode was not activated.

Exposure setup
Exposure source
Distance between exposed object and exposure source 17 mm
Setup The phone was mounted to the left side of the subject's head parallel to the medial plane in a normal use position. It was placed between the subject's head and the head rest of the PET scanner to which it was fastened to prevent any movement. The loudspeaker of the phone was removed. Acoustic and thermal cues were ruled out by two pilot experiments.
Additional info Subjects performed the memory task with exposure and sham exposure (counterbalanced, double-blind design).
Measurand Value Type Method Mass Remarks
power 0.25 W mean - - -
SAR 0.993 W/kg - measured 10 g -
SAR 2 W/kg maximum cf. remarks 10 g extrapolated

Exposed system:

Methods Endpoint/measurement parameters/methodology

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

Main outcome of study (acc. to author)

Exposure to an active mobile phone produced a relative decrease in regional cerebral blood flow bilaterally in the auditory cortex but no regional cerebral blood flow alterations were revealed in the area of maximum electromagnetic field. It is possible that these findings were caused by the electromagnetic field emitted by the active mobile phone.
A more likely interpretation of the present data were a result of an auditory signal from the battery of the active mobile phone. Therefore, it is not reasoned to attribute this result to the electromagnetic field emitted by the phone.

Study character:

Study funded by

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