Nocturnal excretion of a urinary melatonin metabolite among electric utility workers.
Objectives The effects of 60-Hz magnetic field and ambient light exposures on the pineal hormone melatonin were studied among electric utility workers.
Methods Personal exposure was measured at 15-second intervals over 3 consecutive 24-hour periods.
Exposure metrics based on magnetic field intensity, intermittence, or temporal stability were calculated for periods of work, home, and sleep.
A rate-of-change metric (RCM) was used to estimate intermittence, and the standardized RCM (RCMS=RCM/standard deviation) was used to evaluate temporal stability.
The effects of magnetic field exposure on total overnight 6-hydroxymelatonin sulfate (6-OHMS) excretion and creatinine-adjusted nocturnal 6-OHMS (6-OHMS/cr) concentration were analyzed with adjustment for age, month, and light exposure.
Results Magnetic field intensity, intermittence, or cumulative exposure had little influence on nocturnal 6-OHMS excretion.
Residential RCMS magnetic field exposures were associated with lower nocturnal 6-OHMS/cr concentrations.
In multivariate statistical analyses, the interaction term for geometric mean and RCMS magnetic field exposures at home was associated with lower nocturnal 6-OHMS/cr and overnight 6-OHMS levels.
Modest reductions in the mean 6-OHMS levels occurred after RCMS exposures during work. (...)
Mots-clés Pascal : Compagnie électricité, Champ magnétique, Toxicité, Chronobiologie, Eclairage, Homme, Exposition professionnelle, Médecine travail, Mélatonine, Epiphyse, Rythme circadien, Rythme biologique
Mots-clés Pascal anglais : Electric utility, Magnetic field, Toxicity, Chronobiology, Lighting, Human, Occupational exposure, Occupational medicine, Melatonin, Pineal body, Circadian rhythm, Biological rhythm
Notice produite par :
Inist-CNRS - Institut de l'Information Scientifique et Technique
Cote : 98-0393528
Code Inist : 002A08E. Création : 25/01/1999.