Stream-dwelling insects and extremely low frequency electromagnetic fields: a ten-year study

Changes in the structure of benthic insect communities at an experimental site and at a reference site in the Ford River, Michigan were monitored over a 10-year period to determine whether extremely low frequency electromagnetic fields (ELF) affected those communities. Five of 10 biotic parameters monitored are presented: taxon evenness (J), richness (S), numerical dominance of chironomids, and total insect mass. Data were separated into three seasons because coefficient of variation values were lower in the summer than in the spring and fall. Two-way ANOVA tests for the biotic variables were often significantly different between sites and among years, but the interaction terms were less frequently significant. Biotic parameters were regressed against stream discharge, water temperatures, years, and ELF cumulative ground field exposures. At the experimental site, discharge accounted for more variation than did water temperature or years for all biotic parameters except chironomid numerical dominance in the fall. Intervention analyses, using the B.A.C.I parametric or the R.I.A non-parametric showed significant differences in three of 15 cases; namely, for the highly varying chironomid numerical dominance values in the spring and fall and for the low varying total insect mass values in the summer. For those tests, the Before Impact period spanned April 1984 through May 1986. The After Impact period (full ELF power) spanned June 1989 through August 1993. Trend analysis for total insect mass at the experimental site in the summer showed discharge to be more important than water temperatures or ELF ground field exposures. Natural physical factors appear to be more important than the anthropogenic ELF fields in accounting for seasonal and yearly changes in the community.     

Exposure to power frequency magnetic fields suppresses X-ray-induced apoptosis transiently in Ku80-deficient xrs5 cells

In an attempt to determine whether exposure to extremely low frequency (ELF) electromagnetic fields can affect cells, Ku80-deficient cells (xrs5) and Ku80-proficient cells (CHO-K1) were exposed to ELF electromagnetic fields. Cell survival, and the levels of the apoptosis-related genes p21, p53, phospho-p53 (Ser(15)), caspase-3 and the anti-apoptosis gene bcl-2 were determined in xrs5 and CHO-K1 cells following exposure to ELF electromagnetic fields and X-rays. It was found that exposure of xrs5 and CHO-K1 cells to 60 Hz ELF electromagnetic fields had no effect on cell survival, cell cycle distribution and protein expression. Exposure of xrs5 cells to 60 Hz ELF electromagnetic fields for 5 h after irradiation significantly inhibited G(1) cell cycle arrest induced by X-rays (1 Gy) and resulted in elevated bcl-2 expression. A significant decrease in the induction of p53, phospho-p53, caspase-3 and p21 proteins was observed in xrs5 cells when irradiation by X-rays (8 Gy) was followed by exposure to 5 mT ELF magnetic fields. Exposure of xrs5 cells to the ELF electromagnetic fields for 10 h following irradiation significantly decreased X-ray-induced apoptosis from about 1.7% to 0.7%. However, this effect was not found in CHO-K1 cells within 24 h of irradiation by X-rays alone and by X-rays combined with ELF electromagnetic fields. Exposure of xrs5 cells to 60 Hz ELF electromagnetic fields following irradiation can affect cell cycle distribution and transiently suppress apoptosis by decreasing the levels of caspase-3, p21, p53 and phospho-p53 and by increasing bcl-2 expression.     

Hypothesis: The risk of childhood leukemia is related to combinations of power-frequency and static magnetic fields

We present a hypothesis that the risk of childhood leukemia is related to exposure to specific combinations of static and extremely-low-frequency (ELF) magnetic fields. Laboratory data from calcium efflux and diatom mobility experiments were used with the gyromagnetic equation to predict combinations of 60 Hz and static magnetic fields hypothesized to enhance leukemia risk. The laboratory data predicted 19 bands of the static field magnitude with a bandwidth of 9.1 μT that, together with 60 Hz magnetic fields, are expected to have biological activity. We then assessed the association between this exposure metric and childhood leukemia using data from a case-control study in Los Angeles County. ELF and static magnetic fields were measured in the bedrooms of 124 cases determined from a tumor registry and 99 controls drawn from friends and random digit dialing. Among these subjects, 26 cases and 20 controls were exposed to static magnetic fields lying in the predicted bands of biological activity centered at 38.0 μT and 50.6 μT. Although no association was found for childhood leukemia in relation to measured ELF or static magnetic fields alone, an increasing trend of leukemia risk with measured ELF fields was found for subjects within these static field bands (P for trend = 0.041). The odds ratio (OR) was 3.3 [95% confidence interval (CI) = 0.4–30.5] for subjects exposed to static fields within the derived bands and to ELF magnetic field above 0.30 μT (compared to subjects exposed to static fields outside the bands and ELF magnetic fields below 0.07 μT). When the 60 Hz magnetic fields were assessed according to the Wertheimer-Leeper code for wiring configurations, leukemia risks were again greater with the hypothesized exposure conditions (OR = 9.2 for very high current configurations within the static field bands: 95% CI = 1.3–64.6). Although the risk estimates are based on limited magnetic field measurements for a small number of subjects, these findings suggest that the risk of childhood leukemia may be related to the combined effects of the static and ELF magnetic fields. Further tests of the hypothesis are proposed. © 1995 Wiley-Liss, Inc.     

Oviposition and development of Drosophila modified by magnetic fields

Drosophila flies placed in a habitat with two lateral boxes demonstrated sensitivity to magnetic fields: Oviposition decreased by exposure to pulsated extremely low frequency (ELF) (100)Hz, 1.76 miliTesla (mT) and sinusosidal fields (50 Hz, 1 mT), while there was no initial effect of exposure to a static magnetic field (4.5 mT). Drosophila eggs treated for 48 h with the above described fields showed that (1) mortality of eggs was lower in controls than in eggs exposed to all tested magnetic fields; (2) mortality of larvae increased when a permanent magnet was used; (3) mortality of pupae was highest when a permanent magnet was used; and (4) general adult viability was highest in controls (67%) and diminished progressively when eggs were exposed to pulsated (55%), sinusoidal (45%), and static (35%) magnetic fields.     

A human source for ELF magnetic perturbations

ABSTRACT

Current models that frame consciousness in terms of electromagnetic field theory carry implications that have yet to be fully explored. Endogenous weak extremely low frequency (ELF) magnetic fields are generated by ionic charge flow in axons, dendrites and synaptic transmitters. Because neural tissues are transparent to such fields, these provide the basis for the globally unifying qualities required to properly describe consciousness as a field. At the same time, however, an electromagnetic approach predicts partial transmission of this 1–100 nT field, suggesting external interactions similar to the various ELF magnetic perturbations that are linked to homeostatic and endocrine-related physiological effects. It follows that humans may represent an additional, previously unrecognized source of weak (1–10 nT) ambient ELF magnetic fields.     

Proteomics of human primary osteoarthritic chondrocytes exposed to extremely low-frequency electromagnetic fields (ELF EMFs) and to therapeutic application of musically modulated electromagnetic fields (TAMMEF)

Osteoarthritis (OA) is the most frequent joint disease, characterized by degradation of extracellular matrix and alterations in chondrocyte metabolism. Some authors reported that electromagnetic fields (EMFs) can positively interfere with patients affected by OA, even though the nature of the interaction is still debated. Human primary osteoarthritic chondrocytes isolated from the femoral heads of OA-patients undergoing to total hip replacement, were cultured in vitro and exposed 30?min/day for two weeks to extremely-low-frequency electromagnetic field (ELF) with fixed frequency (100?Hz) and to therapeutic application of musically modulated electromagnetic fields (TAMMEF) with variable frequencies, intensities and waveforms. Sham-exposed (S.E.) cells served as control group. Cell viability was measured at days 2, 7 and 14. After two weeks, cell lysates were processed using a proteomic approach. Chondrocyte exposed to ELF and TAMMEF system demonstrated different viability compared to untreated chondrocytes (S.E.). Proteome analysis of 2D-Electrophoresis and protein identification by mass spectrometry showed different expression of proteins derived from nucleus, cytoplasm and organelles. Function analysis of the identified proteins showed changes in related-proteins metabolism (glyceraldeyde-3-phosphate-dehydrogenase), stress response (Mn-superoxide-dismutase, heat-shock proteins), cytoskeletal regulation (actin), proteinase inhibition (cystatin-B) and inflammation regulatory functions (S100-A10, S100-A11) among the experimental groups (ELF, TAMMEF and S.E.). In conclusion, EMFs do not cause damage to chondrocytes, besides stimulate safely OA-chondrocytes and are responsible of different protein expression among the three groups. Furthermore, protein analysis of OA-chondrocytes treated with ELF and the new TAMMEF systems could be useful to clarify the pathogenetic mechanisms of OA by identifying biomarkers of the disease.     

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.     

Sleep inducing effect of low energy emission therapy

The sleep inducing effect of a 15 min treatment with either an active or an inactive Low Energy Emission Therapy (LEET) device emitting amplitude-modulated electromagnetic (EM) fields was investigated in a double-blind cross-over study performed on 52 healthy subjects. All subjects were exposed to both active and inactive LEET treatment sessions, with an interval of at least I week between the two sessions. LEET consists of 27.12 MHz amplitude-modulated (sine wave) EM fields emitted intrabuccally by means of an electrically conducting mouthpiece in direct contact with the oral mucosa. The estimated local peak SAR is less than 10 W/kg in the oral mucosa and 0.1 to 100 mW/kg in brain tissue. No appreciable sensation is experienced during treatment, and subjects are therefore unable to tell whether they are receiving an active or an inactive treatment. In this study the active treatment consisted of EM fields intermittently amplitude-modulated (sine wave) at 42.7 Hz for 3 s followed by a pause of 1 s during which no EM fields were emitted. During the inactive treatment no EM fields were emitted. Baseline EEGs were obtained and 15 min post-treatment EEGs were recorded and analyzed according to the Loomis classification. A significant decrease (paired t test) in sleep latency to stage B2 (?1.78 ± 5.57 min, P = 0.013), and an increase in the total duration of stage B2 (1.15 ± 2.47 min, P = 0.0008) were observed on active treatment as compared with inactive treatment. The deepest sleep stage achieved (B1 to D) following active treatment was also significantly higher than that following inactive treatment (P = 0.040). We conclude 27.12 MHz electromagnetic fields, intermittenly amplitude-modulated at 42.7 Hz, result in a significant sleep inducing effect in healthy subjects. © 1994 Wiley-Liss, Inc.     

Comment: a biological guide for electromagnetic safety: the stress response

Questions of safety of electromagnetic (EM) fields should be based on relevant biological properties, i.e., specific cellular reactions to potentially harmful stimuli. The stress response is a well documented protective reaction of plant and animal cells to a variety of environmental threats, and it is stimulated by both extremely low frequency (ELF) and radio frequency (RF) EM fields. It involves activation of DNA to initiate synthesis of stress proteins. Thermal and non-thermal stimuli affect different segments of DNA and utilize different biochemical pathways. However, both ELF and RF stimulate the same non-thermal pathway. Since the same biochemical reactions are stimulated in different frequency ranges with very different specific absorption rates (SARs), SAR level is not a valid basis for safety standards. Studies of EM field interactions with DNA and with model systems provide insight into a plausible mechanism that can be effective in ELF and RF ranges.     

Resting EEG is affected by exposure to a pulsed ELF magnetic field

An increasing number of reports have demonstrated a significant effect of extremely low frequency magnetic fields (ELF MFs) on aspects of animal and human behavior. Recent studies suggest that exposure to ELF MFs affects human brain electrical activity as measured by electroencephalography (EEG), specifically within the alpha frequency (8-13 Hz). Here we report that exposure to a pulsed ELF MF with most power at frequencies between 0 and 500 Hz, known to affect aspects of analgesia and standing balance, also affects the human EEG. Twenty subjects (10 males; 10 females) received both a magnetic field (MF) and a sham session in a counterbalanced design for 15 min. Analysis of variance (ANOVA) revealed that alpha activity was significantly higher over the occipital electrodes (O1, Oz, O2) [F(1,16) = 6.858; P =.019, eta2 = 0.30] and marginally higher over the parietal electrodes (P3, Pz, P4) [F(1,16) = 4.251; P =.056, eta2 = 0.21] post MF exposure. This enhancement of alpha activity was transient, as it marginally decreased over occipital [F(1,16) = 4.417; P =.052; eta2 = 0.216] and parietal electrodes [F(1,16) = 4.244; P =.056; eta2 = 0.21] approximately 7 min after MF exposure compared to the sham exposure. Significantly higher occipital alpha activity is consistent with other experiments examining EEG responses to ELF MFs and ELF modulated radiofrequency fields associated with mobile phones. Hence, we suggest that this result may be a nonspecific physiological response to the pulsed MFs.     

Perturbations of plant leaflet rhythms caused by electromagnetic radio-frequency radiation

The minute-range up and down rhythms of the lateral leaflets of Desmodium gyrans has been studied when exposed to electromagnetic radiation in the radio-frequency (RF) range. The RF radiation was applied as homogeneous 27.12 MHz fields in specially-designed exposure cells(and in some cases as non-homogeneous radiation of 27 MHz. amplitude modulated by 50 Hz, in front of commercial diathermy equipment). All fields were applied as pulses. We report effects in the leaflet rhythms such as temporary changes in the amplitude, period, and phase. The radiation could also cause temporary or complete cessations of the rhythms. The lowest dose (8 W/cm²) used was still effective. © 1993 Wiley-Liss. Inc.     

Synergistic effects of ionizing radiation and 60 Hz magnetic fields

Experiments designed to evaluate the synergistic production of clastogenic effects by ionizing radiation and 60 Hz magnetic fields were performed using human lymphocytes from peripheral blood. Following exposure to ionizing radiation, cells were cultured in 60 Hz magnetic fields having field strengths up to 1.4 mT. Cells exposed to both ionizing radiation and 60 Hz magnetic fields demonstrated an enhanced frequency of near tetraploid chromosome complements, a feature not observed following exposure to only ionizing radiation. The results are discussed in the context of a multiple-stage model of cellular transformation, employing both initiating and promoting agents. © 1993 Wiley-Liss. Inc.     

No short-term effects of high-frequency electromagnetic fields on the mammalian pineal gland

There is ample experimental evidence that changes of earth-strength static magnetic fields, pulsed magnetic fields, or alternating electric fields (60 Hz) depress the nocturnally enhanced melatonin synthesis of the pineal gland of certain mammals. No data on the effects of high-frequency electromagnetic fields on melatonin synthesis is available. In the present study, exposure to 900 MHz electromagnetic fields [0.1 to 0.6 mW/cm², approximately 0.06 to 0.36 W/kg specific absorption rate (SAR) in rats and 0.04 W/kg in Djungarian hamsters; both continuous and/or pulsed at 217 Hz, for 15 min to 6 h] at day or night had no notable short-term effect on pineal melatonin synthesis in male and female Sprague-Dawley rats and Djungarian hamsters. Pineal synaptic ribbon profile numbers (studied in rats only) were likewise not affected. The 900 MHz electromagnetic fields, unpulsed or pulsed at 217 Hz, as applied in the present study, have no short-term effect on the mammalian pineal gland. Bioelectromagnetics 18:376–387, 1997. © 1997 Wiley-Liss, Inc.     

Extremely low frequency electromagnetic fields (ELF-EMFs) induce in vitro angiogenesis process in human endothelial cells

Effects of extremely low frequency (ELF) electromagnetic fields (EMFs) on activation of angiogenesis were analysed using cultured umbilical human vein endothelial cells (HUVECs). The cultures were exposed to a sinusoidal EMF to intensity of 1 mT, 50 Hz for up to 12 h. EMFs increased the degree of endothelial cell proliferation and tubule formation, coupled by an acceleration in the process of wound healing. Since this process is physiologically accompanied by a large modification in the structural organization of actin and focal adhesions, we analyzed the rearrangement of some cytoskeleton elements demonstrating a major reorganization of the fibres and of the focal adhesion complexes after EMF exposure. Finally, Western blot analysis revealed a significant increase in phosphorylation as well as the overall expression of VEGF receptor 2 (KDR/Flk-1) suggesting that EMFs may modulate in vitro some endothelial functions correlated to angiogenesis through signal transduction pathways dependent on VEGF.     

Stimulation of phagocytosis and free radical production in murine macrophages by 50 Hz electromagnetic fields

Effects of 50 Hz electromagnetic fields on phagocytosis and free radical production were examined in mouse bone marrow-derived macrophages. Macrophages were in vitro exposed to electromagnetic fields using different magnetic field densities (0.5-1.5 mT). Short-time exposure (45 min) to electromagnetic fields resulted in significantly increased phagocytic uptake (36.3% +/- 15.1%) as quantified by measuring the internalization rate of latex beads. Stimulation with 1 nM 12-0-tetradecanoylphorbol-13-acetate (TPA) showed the same increased phagocytic activity as 1 mT electromagnetic fields. However, co-exposure to electromagnetic fields and TPA showed no further increase of bead uptake, and therefore we concluded that because of the absence of additive effects, the electromagnetic fields-induced stimulation of mouse bone marrow-derived macrophages does not involve the protein kinase C signal transduction pathway. Furthermore, a significant increased superoxide production after exposure to electromagnetic fields was detected.     

STUDY ON GAP JUNCTIONAL INTERCELLULAR COMMUNICATION INHIBITION BY ELF MAGNETIC FIELDS USING FRAP METHOD

Inhibition of gap junctional intercellular communication (GJIC) is an important event in the multistage process of carcinogenesis. Our previous study showed that extremely low frequency (ELF) magnetic fields (MFs) inhibit GJIC, and enhance the suppression of GJIC induced by 12-O-tetradecanoylphorbol-13-acetate (TPA) using a microinjection technique. In the present study, the inhibition of GJIC by ELF MFs and its threshold were further studied with fluorescence recovery after photobleaching (FRAP) technique. The results indicated that the FRAP technique is more sensitive in detecting the changes of GJIC than microinjection, and the threshold level is 0.4 mT for GJIC suppression by 50 Hz MFs. In addition, 0.2 mT, or more than 0.2 mT ELF can enhance the inhibition of GJIC induced by TPA. We concluded that MFs thus might act as a cancer promoter or work in synergy with other cancer promoters. The data also provide grounds to revise the reference standard of ELF MFs exposure.