Non-thermal Intensities Research Articles

Thiol Homeostasis in The Crystalline Eye and Influence on It Irradiation by Decimeter Electromagnetic Radiation (Experiments on Rats)

Electromagnetic radiation (EMR) in the microwave range, even at non-thermal intensity, causes significant biochemical and physiological changes in living organisms, which are supposed to be associated with their possible oxidative effect. This work is devoted to the study of the mechanism of realization of the EMR effect in the eye lens at the level of redox state elements, based on the fact that this organ is the most suitable model: it functions semiautonomously and has a well-organized system of antioxidant protection. The transparency of the lens is maintained by preserving the redox balance, in which the homeostasis of thiol compounds of protein and non-protein nature plays an important role. Our experiments were performed on rats using 460 MHz EMR for exposure at non-thermal intensities (power flux density between 10 and 30 µW/cm2). It has been shown that chronic exposure to EMR for up to two weeks caused changes in the redox state of the lens, which manifested in changes in the level of lipid peroxidation processes and the content of thiols of various natures. The substructures of the lens (cortical and nuclear regions) reacted to EMR exposure in different ways. Depending on the EMR intensity, pro- and antioxidant characters were revealed in their reactions. The dynamics of the oxidative reaction of lens substructures were also different under high- and low-intensity exposure. The character of the kinetics of changes in the products of oxidative reactions (malondialdehyde and lipid hydroperoxides) and reducing agents (non-protein and protein SH groups) in the lens of the irradiated organism suggested the role of the enzymatic thiolation-dethiolation system to preserve the redox balance in the substructures of the lens. In addition, the results on changes (kinetics) in the content of various protein SH-groups, i.e., hidden inside the protein molecule and exposed on its surface, during EMR exposure, as well as the data available in the literature, allow us to put forward suggestions about the supramolecular mechanism of homeostasis regulation, in particular, thiol homeostasis regulation in such high-protein structures as the lens, which can be realized by aggregation-disaggregation of protein molecules (crystallins in the case of the lens). Our results can serve as a basis for developing a new non-invasive approach to cataract prevention using low-intensity microwave radiation.

Crystalline lens: redox changes in response to the action of non-ionizing electromagnetic radiation

Electromagnetic radiation (EMR) in the microwave range, even at non-thermal intensity, causes significant biochemical and physiological changes in living organisms, which are supposed to be associated with its possible oxidative effect. This work is devoted to the study of the mechanism of realization of the EMR effect in the eye lens at the level of redox state elements, based on the fact that this organ is the most suitable model: it functions semi-autonomously and has a well-organized system of antioxidant protection. The transparency of the lens is maintained by preserving the redox balance, in which the homeostasis of thiol compounds of protein and non-protein nature plays an important role. Our experiments were performed on rats using 460 MHz EMR for exposure at non-thermal intensities (power flux density between 10 and 30 µW/cm2). It has been shown that chronic exposure to EMR for up to two weeks caused changes in the redox state of the lens, which manifested in changes in the level of lipid peroxidation processes and the content of thiols of various natures. The substructures of the lens (cortical and nuclear regions) reacted to EMR exposure in different ways. Depending on the EMR intensity, pro- and antioxidant characters were revealed in their reactions. The dynamics of the oxidative reaction of lens substructures were also different under high- and low-intensity exposure. The character of the kinetics of changes in the products of oxidative reactions (malondialdehyde and lipid hydroperoxides) and reducing agents (non-protein and protein SH groups) in the lens of the irradiated organism suggested the role of the enzymatic thiolation-dethiolation system to preserve the redox balance in the substructures of the lens. In addition, the results on changes (kinetics) in the content of various protein SH-groups, i.e., hidden inside the protein molecule and exposed on its surface, during EMR exposure, as well as the data available in the literature, allow us to put forward suggestions about the supramolecular mechanism of homeostasis regulation, in particular, thiol homeostasis regulation in such high-protein structures as the lens, which can be realized by aggregation-disaggregation of protein molecules (crystallins in the case of the lens). Our results can serve as a basis for developing a new non-invasive approach to cataract prevention using low-intensity microwave radiation.

От электромагнитного смога до электромагнитного хаоса. К оценке опасности мобильной связи для здоровья населения

Over the past 25 years, there has been a global change in the electromagnetic environment on the Earth, associated with the widest use of wireless communications by the population, which significantly changed the situation of artificial electromagnetic pollution of the external environment and the methodology for assessing the health risks of all population groups. In these difficult conditions, nevertheless, many authors in their conclusions neglect the views established in radiobiology in assessing the danger of exposure to electromagnetic radiation of ultrahigh frequencies (EMR microwave), which is associated, for example, with the notions of a critical organ or critical system, the possibility of accumulating adverse effects and the formation of residual damage (long-term consequences). Almost daily brain irradiation of the EMR of the microwave does not attract their attention. The work uses classical radiobiological approaches to assess the danger of electromagnetic radiation in the microwave range of low non-thermal intensities, including mobile communication for the population and presents some data on the negative impact on public health, including children – mobile phone users. On specific examples, the facts of the relative increase in the risk of developing brain tumors after a long period of active use of cell phones are considered. In many countries, there is a complete disregard for the precautionary principle proposed by the WHO. Children for the first time in the entire period of civilization are included in the risk group. At the same time, in many countries there is a complete disregard for this principle and the recommendations of the International Agency for Research on Cancer (IARC) are ignored. Even before the era of the development of mobile communications, there were significant differences in the approaches to developing acceptable doses for microwave EMR, but discussions on the possible adverse biological effects of non-thermal low levels of these emissions are still ongoing. At the same time, we can note a positive trend associated with the fact that almost all the leading countries of Europe are already correctly assessing the real danger of the MP and have their own more stringent regulations than in Russia (Austria, France, Italy etc.). At the same time, we observe the silence of some scientists and important officials in many countries about the possible danger to the population of EMP mobile communications. As a fact, opposite decisions are made about the prevention and protection of the population, including children. At present, the current situation can be described as electromagnetic chaos in the habitat of the population. In our opinion, in the conditions of the existing electromagnetic chaos, it is necessary to inform the population that mobile communication in the absence of self-limitation can be dangerous to health. The population should have an independent choice of the type and the mode of mobile communication. This choice is his voluntary risk.

Induction of Oxidative Stress in Male Rats Subchronically Exposed to Electromagnetic Fields at Non-Thermal Intensities

To investigate the oxidative stress-inducing potential of non-thermal electromagnetic fields in rats. Male Wister rats were exposed to electrical field intensity of 2.3 ± 0.82 uV/m . Exposure was in three forms: continuous waves, or modulated at 900 MHz or modulated GSM-nonDTX. The radio frequency radiation (RFR) was 1800 MHz, specific absorption radiation (SAR) (0.95-3.9 W/kg) for 40 and/or 60 days continuously. Control animals were located > 300 m from base station, while sham control animals were located in a similar environmental conditions, but in the vicinity of a non-functional base station. The rats were assessed for thiobarbituric and reactive species (TBARS), reduced glutathione (GSH) content, catalase activity, glutathione reductase (GR) and glucose residue after 40 and 60 days of exposure. At 40 days, electromagnetic radiation failed to induce any significant alterations. However, at 60 days of exposure various attributes evaluated decreased. The respective decreases in both nicotinamide adenine dinucleotide phosphate (NADPH) and Ascorbate- linked lipid peroxidation (LPO) with concomitant diminution in enzymatic antioxidative defense systems resulted in decreased glucose residue. The present studies showed some biochemical changes that may be associated with a prolong exposure to electromagnetic fields and its relationship to the activity of antioxidant system in rat Regular assessment and early detection of antioxidative defense system among people working around the base stations are recommended.

Gene and Protein Expression following Exposure to Radiofrequency Fields from Mobile Phones

BackgroundSince 1999, several articles have been published on genome-wide and/or proteome-wide response after exposure to radiofrequency (RF) fields whose signal and intensities were similar to or typical of those of currently used mobile telephones. These studies were performed using powerful high-throughput screening techniques (HTSTs) of transcriptomics and/or proteomics, which allow for the simultaneous screening of the expression of thousands of genes or proteins.ObjectivesWe reviewed these HTST-based studies and compared the results with currently accepted concepts about the effects of RF fields on gene expression. In this article we also discuss these last in light of the recent concept of microwave-assisted chemistry.DiscussionTo date, the results of HTST-based studies of transcriptomics and/or proteomics after exposure to RF fields relevant to human exposure are still inconclusive, as most of the positive reports are flawed by methodologic imperfections or shortcomings. In addition, when positive findings were reported, no precise response pattern could be identified in a reproducible way. In particular, results from HTST studies tend to exclude the role of a cell stressor for exposure to RF fields at nonthermal intensities. However, on the basis of lessons from microwave-assisted chemistry, we can assume that RF fields might affect heat-sensitive gene or protein expression to an extent larger than would be predicted from temperature change only. But in all likelihood, this would concern intensities higher than those relevant to usual human exposure.ConclusionsThe precise role of transcriptomics and proteomics in the screening of bioeffects from exposure to RF fields from mobile phones is still uncertain in view of the lack of positively identified phenotypic change and the lack of theoretical, as well as experimental, arguments for specific gene and/or protein response patterns after this kind of exposure.

Mobile phones, mobile phone base stations and cancer: a review

There have been reports in the media and claims in the courts that radiofrequency (RF) emissions from mobile phones are a cause of cancer, and there have been numerous public objections to the siting of mobile phone base antennas because of a fear of cancer. This review summarizes the current state of evidence concerning whether the RF energy used for wireless communication might be carcinogenic. Relevant studies were identified by searching MedLine with a combination of exposure and endpoint terms. This was supplemented by a review of the over 1700 citations assembled by the Institute of Electrical and Electronics Engineers (IEEE) International Committee on Electromagnetic Safety as part of their updating of the IEEE C95.1 RF energy safety guidelines. Where there were multiple studies, preference was given to recent reports, to positive reports of effects and to attempts to confirm such positive reports. Biophysical considerations indicate that there is little theoretical basis for anticipating that RF energy would have significant biological effects at the power levels used by modern mobile phones and their base station antennas. The epidemiological evidence for a causal association between cancer and RF energy is weak and limited. Animal studies have provided no consistent evidence that exposure to RF energy at non-thermal intensities causes or promotes cancer. Extensive in vitro studies have found no consistent evidence of genotoxic potential, but in vitro studies assessing the epigenetic potential of RF energy are limited. Overall, a weight-of-evidence evaluation shows that the current evidence for a causal association between cancer and exposure to RF energy is weak and unconvincing. However, the existing epidemiology is limited and the possibility of epigenetic effects has not been thoroughly evaluated, so that additional research in those areas will be required for a more thorough assessment of the possibility of a causal connection between cancer and the RF energy from mobile telecommunications.

Nonthermal effects of extremely high-frequency microwaves on chromatin conformation in cells in vivo-dependence on physical, physiological, and genetic factors

There is a substantial number of studies showing biological effects of microwaves of extremely high-frequency range [i.e., millimeter waves (MMWs)] at nonthermal intensities, but poor reproducibility was reported in few replication studies. One possible explanation could be the dependence of the MMW effects on some parameters, which were not controlled in replications. The authors studied MMW effects on chromatin conformation in Escherichia coli (E. coli) cells and rat thymocytes. Strong dependence of MMW effects on frequency and polarization was observed at nonthermal power densities. Several other factors were important, such as the genotype of a strain under study, growth stage of the bacterial cultures, and time between exposure to microwaves and recording of the effect. MMW effects were dependent on cell density during exposure. This finding suggested an interaction of microwaves with cell-to-cell communication. Such dependence on several genetic, physiological, and physical variables might be a reason why, in some studies, the authors failed to reproduce the original data of others.

Power-Dependent Rearrangement in the Spectrum of Resonance Effect of Millimeter Waves on the Genome Conformational State ofEscherichia ColiCells

The Escherichia coli cells K12 AB1157 from the stationary stage of growth were exposed to millimeter waves (MMW) at power densities (PD) from 10−8 W/cm2 to 3 × 10−3 W/cm2. Frequency dependencies during exposure within the range of 51.655–51.688 GHz were studied for two cell concentrations (4 × 107 and 4 × 108 cells/ml). The changes in the genome conformational state (GCS) were analyzed by the method of anomalous viscosity time dependence (AVTD). The resonant effect with the resonance frequency of 51.675 ± 0.001 GHz was observed in the PD range of 10−18-10−8 W/cm2. Left-handed polarized MMW was shown to be more effective than right-handed circular polarization at this resonance. At PDs more than 10−6 W/cm2 the 51.675 GHz resonance effect decreased significantly. As the 51.675 GHz resonance decreased, a statistically significant effect was observed with its maximum at 51.668 ± 0.002 GHz. The results were compared to data of previous studies performed at the resonance frequency of 51.755 GHz. All resonance effects depended on the concentration of cells during exposure, which implies a cell-to-cell interaction during resonance response (cooperativity of resonance response). At all resonance frequencies, an effect was observed at very low nonthermal intensities: 10−18 W/cm2 for 51.755 GHz and 51.675 GHz; 10−14 W/cm2 for 51.668 GHz. The values of three resonance frequencies were stable in wide PD ranges within 10−18-10−3 W/cm2. The half-widths of the resonances showed different dependencies on PD, changing from 2–3 MHz to 16–17 MHz (51.675 GHz, 51.668 GHz) or 100 MHz (51.755 GHz). The significant rearrangement in the spectrum of resonance response was observed in the 10−8-10−4 W/cm2. All three resonances were involved in this rearrangement which can be explained in the framework of the model of electron-conformational interactions.