Do magnetic fields cause increased risk of childhood leukemia via melatonin disruption?

Abstract

Epidemiological studies have reported associations between exposure to power frequency magnetic fields and increased risk of certain cancer and noncancer illnesses. For childhood leukemia, a doubling of risk has been associated with exposures above 0.3/0.4 microT. Here, we propose that the melatonin hypothesis, in which power frequency magnetic fields suppress the nocturnal production of melatonin in the pineal gland, accounts for the observed increased risk of childhood leukemia. Such melatonin disruption has been shown in animals, especially with exposure to electric and/or rapid on/off magnetic fields. Equivocal evidence has been obtained from controlled laboratory magnetic field exposures of volunteers, although the exposure conditions are generally atypical of neighborhood exposures. In contrast, support for the hypothesis is found in the body of studies showing magnetic field disruption of melatonin in human populations chronically exposed to both electric and magnetic fields associated with electricity distribution. Further support comes from the observation that melatonin is highly protective of oxidative damage to the human haemopoietic system. Aspects of the hypothesis are amenable to further investigation.

Association of geomagnetic disturbances and suicides in Japan, 1999–2010

“…If geomagnetic storms can desynchronize circadian rhythms and melatonin production, as has been reported previously [17], there is a possibility that the effect does not have a quick impact but, rather, a slow one. We, therefore, believe that an analysis using monthly suicides and geomagnetic activity data is meaningful.…”

A 1-μT extremely low-frequency electromagnetic field vs. sham control for mild-to-moderate hypertension: a double-blind, randomized study

“…One potential hypothesis is that the effect of EMFs may be mediated by melatonin release. There is good evidence showing that EMF affects melatonin release, 26 and Reiter et al suggest that the night time rise in endogenous circulating melatonin levels may be inversely related to the reduction in night time BP. 27 In this study, we asked each subject to undergo their BP measurements at the same time of day (as far as possible) over the entire duration of the study period.…”

The effects of extremely low frequency magnetic fields on mutation induction in mice

“…The presence of light is detected by non-rod and non-cone receptors in the retina. Once the light intensity declines below a threshold of ~10 lux (Henshaw & Reiter, 2005), a signal is sent via the retinohypothalmic tract to the suprachiasmatic nuclei (Okamura et al, 2002), which in turn prompts the regulation of melatonin production, primarily in the pineal gland through the parenchymatous cells (Singh & Jadhav, 2014).…”

“…For example, melatonin in animals has been illustrated by numerous studies to be highly protective of the foetus against oxidative damage (reviewed in Henshaw & Reiter, (2005)). This suggestion is of note following the proposed general model pertaining to the onset and progression of childhood leukaemia which assumes that any initial event(s) occurs in utero (Greaves, 1999) (Chapter 1.2).…”