No association between occupational exposure to ELF magnetic field and urinary 6‐sulfatoximelatonin in workers

Abstract

A suppression in melatonin secretion is one of the mechanisms proposed to explain the possible adverse effects of extremely low frequency magnetic fields (ELF-MF), but the results of research are inconclusive. This study investigated the effect of occupational ELF-MF exposure on 6-sulfatoximelatonin (6-OHMS). Exposure was monitored for three complete work shifts in 59 workers using personal exposure meters. Environmental exposure was also evaluated. Urinary 6-OHMS in morning samples, an indicator of night-time melatonin production, was measured. Urine was collected twice on Friday and the following Monday. Workers were classified according to ELF exposure as low exposed (<or=0.2 microT) or higher exposed (>0.2 microT): 6-OHMS did not differ between groups (P > .05) in either Friday or Monday urine samples. In addition, 6-OHMS was not related to exposure under multivariate analysis. The ratio between 6-OHMS in Monday versus Friday samples was also calculated to test the hypothesis of a possible variation in pineal function after 2 days, interruption of occupational ELF-MF exposure: again no exposure-related difference was observed. Our results do not support the hypothesis that occupational exposure to ELF-MF significantly influences melatonin secretion.

Effect of occupational EMF exposure from radar at two different frequency bands on plasma melatonin and serotonin levels

“…The latter effect however, has been found in exposure group I (registering minor but not significant difference in melatonin level), which is consistent with the previous findings as well. Other studies reporting no alteration in melatonin concentration (Bortkiewicz et al, 2002;Yellon and Truong, 1998;Gobba et al, 2006) with parallel investigations observing increase or decrease in melatonin levels reflect the inconsistency in this field of investigation. This variation in the interaction of EMF and hence its influence on the living system points towards the complex bio-interaction mechanism and biological sensitivity towards EMF.…”

Effects of power frequency electromagnetic fields on melatonin and sleep in the rat

“…Inhibitory effects of magnetic fields on melatonin production covering a variety of exposure paradigms have been found (19, 42–47). There is also a preponderance of negative results (29, 31, 32, 35, 44, 48, 49). This report demonstrated a mild stimulatory effect, which has also been reported (36, 50).…”

“…In fact, several studies have found no changes in circulatory melatonin after exposure to EMFs (29–35). Finally, there have been a few studies where measurable albeit small increases in melatonin either during or after EMF exposure have been reported (36, 50).…”

Influence of Electric, Magnetic, and Electromagnetic Fields on the Circadian System: Current Stage of Knowledge

“…It should be underlined that a moderate number of epidemiological studies showed no effect of the exposure to ELF-MF on melatonin secretion [33–37]. Gobba et al [33] noted similar levels of 6-sulfatoxymelatonin excretion in two groups of workers exposed to fields ≤0.2  μ T and >0.2  μ T. No association between residential exposure to a 60 Hz magnetic field and 6-sulfatoxymelatonin excretion was observed in adults aged 50–81 years [34].…”

“…Gobba et al [33] noted similar levels of 6-sulfatoxymelatonin excretion in two groups of workers exposed to fields ≤0.2  μ T and >0.2  μ T. No association between residential exposure to a 60 Hz magnetic field and 6-sulfatoxymelatonin excretion was observed in adults aged 50–81 years [34]. Touitou et al [35] showed that the long-term exposure to ELF-MF did not change the level and diurnal secretion of melatonin.…”