Low Level Ionizing Radiation and Non-Ionizing Radiation: Mitigating their Effects with Melatonin Russel J. Reiter, Ph.D., M.D.(h.c.), D.Sc.(h.c.) University of Texas Health Science Center San Antonio, Texas, USA
Bioeffects (physiological, biochemical, molecular biological or behavioral) of exposure to electromagnetic fields
Free radicals account for molecular damage due to radiation exposure
Body functions exhibit circadian rhythms which are essential for optimal health; circadian disruption or chronodisruption has health consequences
Visible portions of the electromagnetic spectrum disrupt circadian rhythms and inhibit melatonin
Circadian rhythms are regulated by the biological clock (suprachiasmatic nuclei) The biological clock is regulated by visible electromagnetic radiation
Circadian vision (unconscious vision) is mediated by wavelengths between 460 and 480 nm (blue light)
An endogenously-produced antioxidant Melatonin protects against molecular damage due to ionizing and non-ionizing radiation
Circadian melatonin rhythm is regulated by the biological clock and blue wavelengths of light
Light (blue light) disrupts circadian rhythms and suppresses melatonin; this response is intensity-dependent Melatonin is a documented anti-cancer agent; because light inhibits melatonin, it is classified as a Group 2A carcinogen
Does non-visible electromagnetic radiation influence circadian rhythms and, if so, are there biological or health consequences?
Wertheimer, N., and Leeper E. Electrical wiring configurations and childhood cancers American Journal of Epidemiology 1979; 109(3): 273-284 -------------------------------- Electrical wiring configurations with high current flow are associated with childhood cancer; the practical significance of the correlation lies in the prevalence of high current wiring not in any very high risk posed by the wiring
The instrumentation used to manipulate the magnetic field [magnetic field was inverted either by means of a relay switch (instantaneous) or manually with an integrating potentiometer (1 sec)] Lerchl A et al, J Pineal Res
The conversion of tryptophan to melatonin as it occurs in the pineal gland When melatonin is synthesized in the pineal gland it is immediately released
Perturbations of a static magnetic field suppressed pineal melatonin production Lerchl A et al, J Pineal Res, 1991
Search coil between Helmholtz coils monitored rate of change of generated magnetic field by measuring induced current The induced current was assumed to have caused the reduction in melatonin production Reiter RJ et al, FASEB J
Visible and non-visible radiation influence blood melatonin levels
Perturbations of the static magnetic field have often, but not always, found to reduce pineal melatonin production indicating disturbances in circadian melatonin rhythm Reiter RJ et al, EPRI TR-107238
Effects of 6 weeks continuous exposure to 50Hz magnetic field inhibits pineal and plasma melatonin levels Kato M et al, Neurosci Lett
Effect of exposure to 60Hz, one gauss magnetic field for 15 min 2 hour before lights off on nocturnal pineal and plasma melatonin levels Yellon SM et al, J Pineal Res
Bioeffects (physiological, biochemical, molecular biological or behavioral) of exposure to electromagnetic fields
Radiofrequency (RF) radiation from mobile phones postulated to cause neurological effects: 1.Headaches 2.Sleep alterations 3.Increased permeability of the blood-brain barrier 4.Changes in neuronal activity 5.Molecular damage Rapacholi, Bioelectromagnetics, 1998 Hossmann, Bioelectromagnetics, 2003 Valentini, Bioecectromagnetics, 2007 Xu, Brain Research, 2010
Free radical generation in cultured cortical neurons exposed to 1,800 MHz radiofrequency electromagneticc field; correlation with mitochondrial DNA damage Xu SC et al, Brain Res
Mobile Phone Radiation and Neural Effects: Experimental Studies Llhan,Clinical Chemistry Acta, 2004 (increased lipid peroxidation and nitric oxide) Koylu, Toxicology and Industrial Health, 2006 (increased lipid peroxidation) Zhao, Toxicology, 2007 (changes in gene expression) Sokolovic, Journal of Radiation Research 2008 (increased lipid peroxidation and protein carbonyls)
Worst case scenario: electromagnetic field exposure occurs co-incident with another factor the induces free radical generation Reiter RJ, 2010
Melatonin suppression and circadian disruption due to electromagnetic field exposure may have a variety of bioeffects and/or health consequences
Conclusions Ionizing and non-ionizing radiation exposure is capable of causing molecular damage (this may lead to cancer) Mechanisms involve oxidative stress (free radicals) Melatonin, an endogenous antioxidant, prevents radiation-induced damage