Inefficiency of electrosmog-shielding mats. Part 2: radio frequency range]

It could already be shown that electromagnetic shielding mats do not reduce but even enhance electric field exposure in daily life situations. By measurements and numerical simulations the claims of manufacturers were checked who pretend that radio frequency electromagnetic fields can be shielded to 99% and more, and transferred to earth by earth cables (if attached). It could be shown that in the radio frequency range such products do not fulfil the justified expectations of customers, but in most cases even cause the opposite. The results depend on the electric properties of the material. Good electric conductivity of shielding mats even considerably increases electromagnetic field exposure. To connect the mats with earth potential by an attached cable might increase the beliefs on a protective effect, however, this is not capable to enhance the shielding effect. The investigation demonstrates that in spite of references made to experts opinions manufacturers claims about the shielding efficiency of radio frequency fields are misleading and fool clients about the real situation. Overall, acquisition and use of electrosmog shielding mats must be discouraged. If at all, shielding can be reached by placing a shielding cover between the source and the person. However, even in this case, efficiency is much lower than promised by manufacturers and decreases even more if it is taken into account that the head naturally remains uncovered and hence unshielded.     

Electric and magnetic fields in cryopreservation

Electromagnetic warming has a long history in cryobiology as a preferred method for recovering large tissue masses from cryopreservation, especially from cryopreservation by vitrification. It is less well-known that electromagnetic fields may be able to influence ice formation during cryopreservation by non-thermal mechanisms. Both theory and published data suggest that static and oscillating electric fields can respectively promote or inhibit ice formation under certain conditions. Evidence is less persuasive for magnetic fields. Recent claims that static magnetic fields smaller than 1 mT can improve cryopreservation by freezing are specifically questioned.     

Threshold effects observed in conformation changes induced by electric fields

Single-stranded polynucleotides are used as model systems for the investigation of conformational changes induced by electric fields. It is demonstrated that the single-strand helix–coil transition in poly(A), poly(dA), and poly(C) can be induced by application of high electric fields. The transition is measured by UV absorbance using polarized light at an angle of 54.8° with respect to the vector of the electric field and by electrodichroism. A linear increase of the absorbance, reflecting the helix-to-coil transition, is observed at increasing field strength. When ions are added to the polymer, electric fields do not induce conformation changes, unless a threshold value of the electric field strength E₀ is exceeded. At field strengths above this threshold, the degree of transition is a linear function of the increase in field strength. The threshold values E₀ show a linear increase with the logarithm of the ion concentration. Bivalent ions cause thresholds at much lower ion concentrations than mo-novalent ions. The shielding efficiency of ions is correlated to the binding affinity of these ions to the polymer. The conformation changes induced by the field and the existence of thresholds can be explained on the basis of dissociation field effects. Similar threshold effects may be expected for other macromolecules as well as for membrane structures and may be important in the regulation of bioelectricity.     

Effects of electromagnetic fields on the motion of Euglena gracilis.

The orientation behavior of Euglena gracilis cultures in electromagnetic fields is shown to agree with the predictions of a model involving only a passive mechanism. The increase in Euglena motor activity with increasing field intensity is demonstrated by measuring various motion parameters by the laser scattering technique. The effect of electric field on the speed of Euglenas is compared with that of temperature. We conclude that the electric field warms up the culture, thus inducing an increase in cell motility.     

In vitro increase of the fluid-phase endocytosis induced by pulsed radiofrequency electromagnetic fields: importance of the electric field component

Nowadays, due to the wide use of mobile phones, the possible biological effects of electromagnetic fields (EMF) become a public health general concern. Despite intensive research, there are no widely accepted theories about the interactions between EMFs and living cells, and the experimental data are often controversial. We examined the effects of mobile phones EMF (envelope frequency of 217 Hz, carrier frequency of 900 MHz and pulse duration of 580 micros) or its pure, low-frequency pulsed electric field component on fluid-phase endocytosis. In both cases, with exposures exceeding 10 min, an increase of the fluid-phase endocytosis rate was observed ( approximately 1.5-fold), on three different cell types. This increase is an all-or-nothing type of response that is occurring for threshold values comprised between 1.3 and 2.6 W/kg for the delivered EMF powers and between 1.1 and 1.5 V/cm for the electric fields intensities depending upon the cell type. The electric component of these EMFs is shown to be responsible for the observed increase. Variations of frequency or pulse duration of the electric pulses are shown to be without effect. Thus, EMF, via their electrical component, can perturb one of the most fundamental physiological functions of the cells-endocytosis.     

A ferromagnetic model for the action of electric and magnetic fields in cryopreservation

Recent discussions in the literature have questioned the ability of electromagnetic exposure to inhibit ice crystal formation in supercooled water. Here we note that strong electric fields are able to disrupt the surface boundary layer of inert air on the surface of materials, promoting higher rates of heat transport. We also note that most biological tissues contain ferromagnetic materials, both biologically precipitated magnetite (Fe₃O₄) as well as environmental contaminants that get accidentally incorporated into living systems. Although present at trace levels, the number density of these particulates is high, and they have extraordinarily strong interactions with weak, low-frequency magnetic fields of the sort involved in claims of electromagnetic cryopreservation. Magnetically-induced mechanical oscillation of these particles provides a plausible mechanism for the disruption of ice-crystal nucleation in supercooled water.     

In vitro increase of the fluid-phase endocytosis induced by pulsed radiofrequency electromagnetic fields: importance of the electric field component

Nowadays, due to the wide use of mobile phones, the possible biological effects of electromagnetic fields (EMF) become a public health general concern. Despite intensive research, there are no widely accepted theories about the interactions between EMFs and living cells, and the experimental data are often controversial. We examined the effects of mobile phones EMF (envelope frequency of 217 Hz, carrier frequency of 900 MHz and pulse duration of 580 μs) or its pure, low-frequency pulsed electric field component on fluid-phase endocytosis. In both cases, with exposures exceeding 10 min, an increase of the fluid-phase endocytosis rate was observed (≈1.5-fold), on three different cell types. This increase is an all-or-nothing type of response that is occurring for threshold values comprised between 1.3 and 2.6 W/kg for the delivered EMF powers and between 1.1 and 1.5 V/cm for the electric fields intensities depending upon the cell type. The electric component of these EMFs is shown to be responsible for the observed increase. Variations of frequency or pulse duration of the electric pulses are shown to be without effect. Thus, EMF, via their electrical component, can perturb one of the most fundamental physiological functions of the cells—endocytosis.     

A mechanism for action of oscillating electric fields on cells

The biological effects of electromagnetic fields have seriously concerned the scientific community and the public as well in the past decades as more and more evidence has accumulated about the hazardous consequences of so-called "electromagnetic pollution." This theoretical model is based on the simple hypothesis that an oscillating external electric field will exert an oscillating force to each of the free ions that exist on both sides of all plasma membranes and that can move across the membranes through transmembrane proteins. This external oscillating force will cause a forced vibration of each free ion. When the amplitude of the ions' forced vibration transcends some critical value, the oscillating ions can give a false signal for opening or closing channels that are voltage gated (or even mechanically gated), in this way disordering the electrochemical balance of the plasma membrane and consequently the whole cell function.     

Biological effects of exposure to magnetic resonance imaging: an overview

The literature on biological effects of magnetic and electromagnetic fields commonly utilized in magnetic resonance imaging systems is surveyed here. After an introduction on the basic principles of magnetic resonance imaging and the electric and magnetic properties of biological tissues, the basic phenomena to understand the bio-effects are described in classical terms. Values of field strengths and frequencies commonly utilized in these diagnostic systems are reported in order to allow the integration of the specific literature on the bio-effects produced by magnetic resonance systems with the vast literature concerning the bio-effects produced by electromagnetic fields. This work gives an overview of the findings about the safety concerns of exposure to static magnetic fields, radio-frequency fields, and time varying magnetic field gradients, focusing primarily on the physics of the interactions between these electromagnetic fields and biological matter. The scientific literature is summarized, integrated, and critically analyzed with the help of authoritative reviews by recognized experts, international safety guidelines are also cited.     

Microbial Mat Boundaries between Chemolithotrophs and Phototrophs in Geothermal Hot Spring Effluents

Among the various microbial mats that develop in geothermal hot springs in solfataric fields, colorless sulfur-turf (ST)—macroscopic white bundles consisting of large sickle-shaped bacteria belonging to Aquificales and elemental sulfur particles–develops in a limited environment of geothermal effluent containing hydrogen sulfide with neutral pH and low in oxygen. Photosynthetic cyanobacterial mat (CY) often grow just downstream of chemolithotrophic ST, or they coexist with ST where the temperature is slightly lower. Knowledge of the environmental regimes of these microbial mats will lead to better understanding of the distribution of thermophilic microorganisms on the Earth and provide clues about evolutionary processes in the microbial ecosystems of the Precambrian era. We studied the environmental parameters of the boundary zone and examined the distribution of these types of mats and measured the in situ growth rates of the microorganisms composing them. In situ examination revealed that temperature and Eh constrain the development of the microbial mats. At the boundary between ST and CY, temperature and Eh ranged between 51.1°C and 63.2°C and between ?112 mV and ?25 mV, respectively. These environmental parameters were not significantly different among Japanese, Yellowstone (North American), and Icelandic hot spring effluents with genetically similar thermal sulfur oxidizers. Sickle-shaped bacteria rarely coexist with cyanobacteria, although they can potentially grow in some CY environments. This suggests that the boundary between ST and CY might be partly determined by exclusive ecological competition.     

Shielding, but not zeroing of the ambient magnetic field reduces stress-induced analgesia in mice.

Magnetic field exposure was consistently found to affect pain inhibition (i.e. analgesia). Recently, we showed that an extreme reduction of the ambient magnetic and electric environment, by mu-metal shielding, also affected stress-induced analgesia (SIA) in C57 mice. Using CD1 mice, we report here the same findings from replication studies performed independently in Pisa, Italy and London, ON, Canada. Also, neither selective vector nulling of the static component of the ambient magnetic field with Helmholtz coils, nor copper shielding of only the ambient electric field, affected SIA in mice. We further show that a pre-stress exposure to the mu-metal box is necessary for the anti-analgesic effects to occur. The differential effects of the two near-zero magnetic conditions may depend on the elimination (obtained only by mu-metal shielding) of the extremely weak time-varying component of the magnetic environment. This would provide the first direct and repeatable evidence for a behavioural and physiological effect of very weak time-varying magnetic fields, suggesting the existence of a very sensitive magnetic discrimination in the endogenous mechanisms that underlie SIA. This has important implications for other reported effects of exposures to very weak magnetic fields and for the theoretical work that considers the mechanisms underlying the biological detection of weak magnetic fields.     

Perception of Risks from Electromagnetic Fields: Lessons for the Future

Technologies based on extremely highfrequency electromagnetic fields, inparticular in the terahertz region, arequite recent and new to the public. While anumber of advantages have been shown,especially in the biomedical area,biological effects and possible healthimplications have not been fullyinvestigated. The experience gained withelectromagnetic fields of lowerfrequencies, from ELF to microwaves,suggests that innovating technologies maycreate concern, or even fear, among thepublic for hypothetical health risks.Social research has shown that worries arerelated to the perception of risks by thepublic more than to their actual existence.Risk perception depends on several factors,many of which are relevant forelectromagnetic fields. They include lackof familiarity with the agent, difficultyin understanding interaction mechanisms,and uncertainty in scientific knowledge.Lessons learnt from the past lead torecommend that specific research onbiological effects of terahertz radiationbe started from the very beginning of thedevelopment of technological applicationsand that a continuous and effectivedialogue be established between thescientific community and the public.     

Effects of sinusoidal 60-Hz electric and magnetic fields on ATP and oxygen levels in the slime mold, Physarum polycephalum

We have previously reported that exposing the vegetative plasmodia stage of Physarum polycephalum to either individual or simultaneously applied electric and magnetic fields (45-75 Hz, 0.14-2.0 G, and 0.035-0.7 V/m) lengthens their mitotic cycle, depresses their rate of reversible shuttle streaming, and lowers their respiration rate. In this article we report the effects of simultaneously applied electromagnetic fields (60 Hz, 1.0 G, 1.0 V/m), electric fields only (60 Hz, 1.0 V/m), magnetic fields only (60 Hz, 1.0 G) on the haploid amoeba of Physarum exposed for 120-180 days. Statistically significant depressions (about 8-11%) in ATP levels were observed with all field conditions; however, respiration was significantly decreased only when amoebae were subjected to either combined fields or electric fields alone. Magnetic fields alone failed to induce a significant decrease in respiration.     

Capacitively coupled electric fields accelerate proliferation of osteoblast-like primary cells and increase bone extracellular matrix formation in vitro

Over the last few years, electric and electromagnetic fields have gained more and more significance in the therapy of bone fracture healing and bone disease. Yet, the underlying mechanisms on a cellular and molecular level are not completely understood. In the present study we have investigated the effects of capacitively coupled, pulsed electric fields on cellular proliferation, alkaline phosphatase activity, and matrix protein synthesis of osteoblast-like primary cells in vitro. Cells were derived from bovine periosteum and electrically stimulated by saw-tooth pulses of 100 V external voltage and 16 Hz frequency. This corresponds to an electric field of 6 kV/m across the cell membranes as could be shown by computer simulation. Field application caused acceleration of cell culture development. A significant increase of proliferation concurrent with an enhancement of alkaline phosphatase activity was observed in sub-confluent cultures. Exposure of confluent osteoblast-like primary cells to electric fields resulted in enhanced synthesis and secretion of extracellular matrix-related proteins. These findings suggest that capacitively coupled electric fields accelerate bone cell proliferation and differentiation in vitro and enhance the synthesis of cells leading to promoted matrix formation and maturation.     

Growth inhibition of Staphylococcus aureus induced by low‐frequency electric and electromagnetic fields

Magnetic field therapy is an established technique in the treatment of pseudarthrosis. In cases of osteomylitis, palliation is also observed. This study focuses on the impact of different electric and electromagnetic fields on the growth of Staphylococcus aureus by in vitro technologies. Cultures of Staphylococcus aureus in fluid and gel‐like medium were exposed to a low‐frequency electromagnetic field, an electromagnetic field combined with an additional electric field, a sinusoidal electric field and a static electric field. In gel‐like medium no significant difference between colony‐forming units of exposed samples and non‐exposed references was detected. In contrast, Staphylococcus aureus concentrations in fluid medium could clearly be reduced under the influence of the four different applied fields within 24 h of experiment. The strongest effects were observed for the direct current electric field which could decrease CFU/ml of 37%, and the low‐frequency electromagnetic field with additional induced electric alternating field with a decrease of Staphylococci concentration by 36%. The effects of the electromagnetic treatment on Staphylococci within fluid medium are significantly higher than in gel‐like medium. The application of low‐frequency electromagnetic fields corroborates clinical situations of bone infections during magnetic field therapy. Bioelectromagnetics 30:270–279, 2009. © 2009 Wiley‐Liss, Inc.     

Do electromagnetic fields interact with electrons in the Na,K‐ATPase?

The effects of low frequency electric and magnetic fields on several biochemical systems, including the Na,K-ATPase, indicate that electromagnetic (EM) fields interact with electrons. The frequency optima for two enzymes in response to EM fields are very close to their turnover numbers, suggesting that these interactions directly affect reaction rates. Nevertheless, generally accepted ideas about Na,K-ATPase function and ion transport mechanisms do not consider interactions with electrons. To resolve the clash of paradigms, we hypothesize interaction with transient electrons and protons that arise from flickering of H-bonds in the hydrated protein. These transient charges in the enzyme could provide a trigger for the sequence of conformation changes that are part of the ion transport mechanism. If the distributions of transient electrons and protons in the membrane are affected by their concentration and the membrane potential, as expected from electric double layer theory, this can account for the different effects of low frequency electric and magnetic fields, as well as for the observation that membrane hyperpolarization reverses the ATPase reaction to generate ATP.     

Mechanism for action of electromagnetic fields on cells

A biophysical model for the action of oscillating electric fields on cells, presented by us before [Biochem. Biophys. Res. Commun. 272(3) (2000) 634-640], is extended now to include oscillating magnetic fields as well, extended to include the most active biological conditions, and also to explain why pulsed electromagnetic fields can be more active biologically than continuous ones. According to the present theory, the low frequency fields are the most bioactive ones. The basic mechanism is the forced-vibration of all the free ions on the surface of a cell's plasma membrane, caused by an external oscillating field. We have shown that this coherent vibration of electric charge is able to irregularly gate electrosensitive channels on the plasma membrane and thus cause disruption of the cell's electrochemical balance and function [Biochem. Biophys. Res. Commun. 272(3) (2000) 634-640]. It seems that this simple idea can be easily extended now and looks very likely to be able to give a realistic basis for the explanation of a wide range of electromagnetic field bioeffects.     

In pursuit of formaldehyde: causally explanatory models and falsification

Falsification no longer is the cornerstone of philosophy of science; but it still looms widely that scientists ought to drop an explanatory hypothesis in view of negative results. We shall argue that, to the contrary, negative empirical results are unable to disqualify causally explanatory hypotheses—not because of the shielding effect of auxiliary assumptions but because of the fact that the causal irrelevance of a factor cannot empirically be established. This perspective is elaborated at a case study taken from the history of plant physiology: the formaldehyde model of photosynthesis, which for about sixty years (1870s to 1930s) dominated the field—despite the fact that in these sixty years all the attempts to conclusively demonstrate even the presence of formaldehyde in plants failed.     

Effects of La3+ on growth,transformation, and gene expression of Escherichia coli

Rare earth elements have been emitted into the environment largely as fertilizer components. This has caused much fear about whether they would influence our environment, especially on the metabolism and genetics of microorganisms. In this article, the trivalent ion of a rare earth element, lanthanum, was studied for the effects on growth, transformation, and gene expression of Escherichia coli. The results showed that La³⁺ at concentrations from 50 to 150 μg/mL stimulated the endogenic metabolism and ectogenic metabolism, but had few effects on gene expression. La³⁺ at lower concentrations from 0.5 to 30 μg/mL inhibit intensively E. coli-absorbing external DNA, decreasing the transformation efficiency. It is also supported by observations using transmission electron microscopy. Our results are significant in understanding the function of rare earth elements to microorganisms and assessing the risk of application of rare earth compounds.