%0 Journal Article %T Nocturnal excretion of a urinary melatonin metabolite among electric utility workers %A Burch, J. B. %A Reif, John S. %A Yost, M. G. %A Keefe, T. J. %A Pitrat, C. A. %J Scandinavian Journal of Work, Environment & Health %D 1998 %8 June 24 %N 3 %@ 0355-3140 %F Burch1998 %X '

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OBJECTIVES ': 'The effects of 60-Hz magnetic field and ambient light exposures on the pineal hormone melatonin were studied among electric utility workers.'

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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.'

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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. The greatest reductions occurred when RCMS exposures both at work and at home were combined; therefore the effects of temporally stable magnetic fields may be integrated over a large portion of the day.'

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CONCLUSION ': 'Results from this study provide evidence that temporally stable magnetic field exposures are associated with reduced nocturnal 6-OHMS excretion in humans.

%K 6-hydroxymelatonin sulfate %K electromagnetic fields %K human %K magnetic fields %K pineal %R 10.5271/sjweh.297 %U https://www.sjweh.fi/show_abstract.php?abstract_id=297 %U https://doi.org/10.5271/sjweh.297 %P 183-189