Study type: Medical/biological study (experimental study)

Daytime 50 Hz magnetic field exposure and plasma melatonin and urinary 6-sulfatoxymelatonin concentration profiles in humans. med./bio.

Published in: J Pineal Res 2001; 31 (3): 234-241

Aim of study (acc. to author)

The effects of a head exposure of human subjects to a 50 Hz magnetic field on plasma melatonin and urine hydroxymelatoninsulfate levels should be investigated.

Background/further details

21 male subjects participated in the study. Each subject attended one continuous exposure session, one intermittent exposure session and one sham exposure session in the afternoon with 1-week intervals in between, respectively.
Blood and urine samples were collected after each exposure session from the evening to the next morning.

Endpoint

Exposure

Exposure Parameters
Exposure 1: 50 Hz
Exposure duration: continuous for 30 minutes
Exposure 2: 50 Hz
Exposure duration: intermittent (15 s on/off cycles) for 30 minutes

General information

ambient AC field was < 0.06 µT (rms) and DC field was 40 µT (rms) at an inclination of 60°N

Exposure 1

Main characteristics
Frequency 50 Hz
Type
Waveform
Polarization
Exposure duration continuous for 30 minutes
Exposure setup
Exposure source
Setup coils were arranged in a "magnetic helmet": a cubic structure formed by six Helmholtz coils, 35 cm in diameter, distributed in the three orthogonal directions; generated field was uniform and parallel to the direction of the local geomagnetic field
Sham exposure A sham exposure was conducted.
Parameters
Measurand Value Type Method Mass Remarks
magnetic flux density 100 µT effective value - - -

Exposure 2

Main characteristics
Frequency 50 Hz
Type
Waveform
Polarization
Exposure duration intermittent (15 s on/off cycles) for 30 minutes
Exposure setup
Exposure source
Parameters
Measurand Value Type Method Mass Remarks
magnetic flux density 100 µT effective value - - -

Reference articles

  • Crasson M et al. (1999): 50 Hz magnetic field exposure influence on human performance and psychophysiological parameters: two double-blind experimental studies.
  • Crasson M et al. (1993): [Preliminary study of 50 Hz magnetic fields exposure effects on some neuropsychological and neuroendocrinal parameters].
  • Cook MR et al. (1992): A replication study of human exposure to 60-Hz fields: effects on neurobehavioral measures.

Exposed system:

Methods Endpoint/measurement parameters/methodology

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

Main outcome of study (acc. to author)

No significant differences were found in either plasma melatonin and urine hydroxymelatoninsulfate levels between continuous exposure, intermittent exposure or sham exposure conditions. However, a tendency to smaller night-time urine hydroxymelatoninsulfate levels after continuous exposure compared to sham exposure was found, particularly in subjects with relatively low natural urine hydroxymelatoninsulfate levels.
The authors conclude that there are no indications for effects of a head exposure of human subjects to a 50 Hz magnetic field on plasma melatonin and urine hydroxymelatoninsulfate levels.

Study character:

Study funded by

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