Oxidative stress-induced biological damage by low-level EMFs:
woensdag, 17 juni 2015 - Categorie: Artikelen
Publicatie: Eur. J. Oncol. Library, vol. 5, pp. 63 - 113, 2010
hoofdstuk in:
www.ramazzini.org/wp-content/uploads/2008/03/Non-thermal-effects-and-mechanisms-of-interaction-between-electromagnetic-fields-and-living-matter_2010.pdf
Oxidative stress-induced biological damage by low-level
EMFs: mechanism of free radical pair electron spinpolarization
and biochemical amplification
Christos D. Georgiou
Professor of Biochemistry, Department of Biology, University of Patras, Greece
Abstract
Low-level electromagnetic field (EMF) interactions with organisms are based on
the physics and chemistry of electron spin shifting of the transient radical pair
and triplet state molecules formed by homolytic bond splitting within cells, and
on the biochemistry of non-linear dynamic processes as they are related to the
biological amplification of the EMF-induced initial effect. These processes, alone
or in combination, could induce biochemical signal transduction interaction
pathways by which weak EMFs can cause organism dysfunction and disease.
EMF effects originate for the most part in the geminate recombination processes
where free radical pairs are created. No recombination permitting electron spin
shifting can result from local EMF effects on unpaired electrons if both free radicals
are tethered by interactions with macromolecules or supramolecular biological
structures at the right separation distance. Any field-induced change in the
concentration of the free radicals that survive recombination may alter the rates
of their subsequent reactions. These effects can become quite pronounced and
harmful for man by existing dynamic, non-linear biological mechanisms that
amplify the biochemical effects of small changes in radical concentrations, especially
those of oxygen-centered free radicals responsible for the creation of genotoxic
oxidative stress. This synergistic mechanism is supported by experimental
evidence from vast EMF exposure studies on various biological systems
(human/animal cell cultures, whole animals, and even plants) covering static
magnetic, extra low frequency and radiofrequency fields (SMF, ELF and RF,
respectively); SMF (as low as 0.05 W/m2), ELF 3-195 Hz (as low as 10 µT) and
RF 400 MHz-300 GHz (as low as 0.2 W/m2 and SAR 0.016 W/kg). In brief, EMF
exposure has been shown to cause high oxidative stress-induced biological
damage, manifested by a substantial increase of peroxidized lipids, oxidized
proteins and fragmented/nicked DNA. Substantial decrease has been also documented
in the antioxidant defense mechanisms, i.e., in the activity of crucial
antioxidant enzymes and in the concentration of endogenous antioxidants.
Exogenous antioxidants and inhibitors of certain ROS/RNS-producing enzymes
reversed all these effects, which is another strong evidence for the causative relation
between oxidative stress and EMF exposure. EMF-induced oxidative stress has been also shown in vitro by the increase of reactive oxygen/nitrogen species
(ROS/RNS) indirectly assessed by non-specific assays. New quantitative and
specific in vivo ROS assays are proposed for the conclusive verification of the
oxidative stress mechanism, as well as specific quantitative indicators of biological
damage that can be used for the reassessment of the EMF exposure limits.
The present report offers a combined free radical pair/oxidative stress mechanism
in order to explain how EMFs can cause disease in man. Moreover, it offers
a scientifically solid background mechanism for the experimental design of
epidemiological studies, while it extends its conclusions to the redefinition of
safer EMF exposure limits for the public.
Key words: disease, EMF, oxidative stress, free radicals, radical pair mechanism
“Are there biological effects? The engineers and the physicists say absolutely not. Their view in general of what living systems consist of, is that the cells are little plastic bags filled with minestrone soup. And you can then, with that sort of a concept, calculate the field strength and the frequencies you would need to produce an effect on the minestrone soup. And this is exactly the concept that was employed after it became apparent that radar systems could heat up the human body. The physicists that were involved in answering the question: Are there effects? And at what level do they occur? And what would be a safe level? Basically, they followed a basic precept, which was to consider a spherical cow; a circular oval object filled with conducting solution and composed of a skin that is transparent to the radio frequency waves that microwave generators produce. And on that basis, they asked: How much does it take to heatthis up? Where does the cow’s temperature start to rise? And that number was calculated and confirmed in actual procedures in the lab using the spherical cow concept. They said, “OK, that’s the number at which you are going to start heating people. Let’s say that’s not such a good idea and we’ll set a level ten times lower as the safe level”…”I have no doubt in my mind that at the present time the greatest polluting element in the earth’s environment is the proliferation of electromagnetic fields.”
Robert O. Becker, M.D., author of the books The Body Electric and Cross Currents: The Perils of
Electropollution (interview: www.emrnetwork.org/pdfs/becker.pdf, accessed on June 2, 2010)
Lees verder in de categorie Artikelen | Terug naar homepage | Lees de introductie