Study type: Medical/biological study (experimental study)

No effects of pulsed radio frequency electromagnetic fields on melatonin, cortisol, and selected markers of the immune system in man med./bio.

Published in: Bioelectromagnetics 2001; 22 (4): 280-287

Aim of study (acc. to author)

Healthy male subjects were tested to see whether or not radiofrequency electromagnetic fields as used in digital wireless telecommunication (GSM standard) have noticeable effects on salivary melatonin, cortisol (indicator of stress), neopterin (vicarious for cellular immune activity), and immunoglobulin A (protective factor in the upper parts of alimentary and respiratory tracts) levels during and several hours after exposure.



Exposure Parameters
Exposure 1: 900 MHz
Modulation type: pulsed
Exposure duration: continuous for 4 h

Exposure 1

Main characteristics
Frequency 900 MHz
  • circular
Exposure duration continuous for 4 h
Modulation type pulsed
Pulse width 577 µs
Repetition frequency 217 Hz
Additional info

GSM standard

Exposure setup
Exposure source
Distance between exposed object and exposure source 10 cm
Chamber The main room of the air conditioned exposure chamber was subdivided into four compartments open at one side. The inside of the exposure chamber and the compartments were shielded against RF EMF.
Setup Each compartment was equipped with a wooden reclining seat and a circularly polarised antenna, individually positioned 10 cm behind the head of the upright sitting test person.
Additional info In double blind trials, each test person attended a total of 20 randomised 4-hour sessions of exposure and sham exposure, equally distributed at day and night, being at least 2 days apart after a day session and at least 3 days apart after a night session.
Measurand Value Type Method Mass Remarks
power density 1 W/m² mean measured - at 10 cm
SAR 0.025 W/kg maximum measured 10 g in the head

Exposed system:

Methods Endpoint/measurement parameters/methodology

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

Main outcome of study (acc. to author)

The data showed that the salivary concentrations of melatonin, cortisol, neopterin and immunoglobulin A did not differ significantly between exposure and sham exposure.

Study character:

Study funded by

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