Study type: Medical/biological study (observational study)

No association between occupational exposure to ELF magnetic field and urinary 6-sulfatoximelatonin in workers med./bio.

Published in: Bioelectromagnetics 2006; 27 (8): 667-673

Aim of study (acc. to author)

To study the effect of occupational extremely low frequency magnetic field exposure on urinary 6-sulphatoxy melatonin (6-OHMS) content in different workers (from clothing production, local utilities company, primary school, engineering industry and other companies).

Background/further details

Urinary 6-OHMS in morning samples is an indicator of night-time melatonin production. Urine was collected twice on friday and the following monday (interruption of occupational exposure).
Exposure was monitored for three complete work shifts in 59 workers using personal exposure meters. Workers were classified as "low exposed" (< or = 0.2 µT) or "higher exposed" (> 0.2 µT).



Exposure Parameters
Exposure 1:
Exposure duration: continuous for 3 complete work shifts

Exposure 1

Main characteristics
  • unspecified
Exposure duration continuous for 3 complete work shifts
Additional info Occupational exposure
Exposure setup
Setup The meters were worn on the hip in a belted pouch. During the sleep, subjects were instructed to leave the meter beside the bed, close to the body, but not near electrical and electronic devices.
Additional info 59 workers, 26 men and 33 women, engaged in different occupations were included in the study: 26 in clothing production, 14 in local utility company, 6 primary school teachers, 5 in engineering industry and a further 8 in other occupations. Morning urine samples were collected twice: 1) on Friday after 4 days of occupational exposure or 2) on Monday after 2 days of no occupational exposure.
Measurand Value Type Method Mass Remarks
magnetic flux density 0.54 µT mean measured - occupational exposure group
magnetic flux density 0.04 µT mean measured - non-occupational exposure group

Exposed system:

Methods Endpoint/measurement parameters/methodology

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

Main outcome of study (acc. to author)

The data do not support the hypothesis that occupational exposure to extremely low frequency magnetic field may affect melatonin secretion.

Study character:

Study funded by

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