Unknown authors · 2010
Early studies tended toward a consistent association between risks for leukemia and brain cancer and residential proximity to power lines having high wire configuration. More recent studies using improved exposure measurement methods have produced inconsistent results, with some suggesting increased risk and others not. Occupational exposures suggested increased risk for leukemia and to a lesser extent brain cancer and Non-Hodgkin lymphoma. Studies of residential exposures and cancer in adults generally suggested no effect. Laboratory work has been unable to demonstrate a biological mechanism that might explain the epidemiological findings.
Unknown authors · 2010
Researchers exposed young male rats to 50 Hz magnetic fields (the same frequency as power lines) and the pesticide atrazine, both separately and together, for 30 days to see if they would damage thyroid function. They found no synergistic effects between the two exposures, though magnetic fields alone caused some structural changes in thyroid tissue that warrant further study.
Unknown authors · 2010
One hundred and twenty Swiss albino mice were equally divided into 6 groups. The study groups were exposed to 1, 2, 3, 4 and 5 microT 50 Hz-EMFs for 40 days. ELF-EMF exposure caused a nonlinear decline of nucleus area, a sharp drop in AgNOR area at 1 microT that then rose to an insignificantly higher level than controls, and no change in mean AgNOR numbers per nucleus. Relative AgNOR area was highest in the 1 microT group and similar in the 5 microT group, while the remaining groups had significantly lower values similar to controls. The field exposure at any intensity did not significantly affect the frequency of either MPBLs or MPCEs, but the number of MN per PBL in the 4 and 5 microT-exposure groups were significantly higher than those of the lower intensity exposure groups.
Unknown authors · 2010
The present study investigated the potential effects of extremely low frequency (ELF) electric field exposure on plasma cholesterol and triglyceride levels of adult male rats. Sixty rats were randomly divided into three groups: controls without exposure, a group exposed to 50 Hz for 10 days, and a group exposed to 50 Hz for 30 days. Total cholesterol concentration in the short-term exposure group was 65.33 ± 15.31 mg/dL and in the long-term exposure group was 59.55 ± 15.01 mg/dL, both significantly lower than the control value of 70.44 ± 19.60 mg/dL. Plasma triglyceride levels were 67.33 ± 15.63 mg/dL in one exposed group and 51.53 ± 14.17 mg/dL in the other, compared with 84.44 ± 16.79 mg/dL in controls.
Unknown authors · 2010
Researchers exposed rats to 50 Hz electric fields (the same frequency as power lines) for either 10 or 30 days and measured cholesterol and triglyceride levels in their blood. Both exposure groups showed significantly lower cholesterol and triglyceride levels compared to unexposed controls, with longer exposure producing greater decreases. This suggests that power line frequency electric fields can alter fat metabolism in mammals.
Grigor'ev IuG et al. · 2010
Unknown authors · 2010
Rats were exposed to 100 and 500 μT ELF-MF for 2 h/day during 10 months. Calcium levels decreased in the ELF-500 exposure group compared to the sham group. Magnesium levels decreased in the ELF-500 exposure group compared to both the sham and ELF-100 exposure groups. Zinc levels were lower in the ELF-500 exposure group than in the sham and ELF-100 exposure groups. No significant differences were found in phosphorus, copper, or iron levels between groups.
Unknown authors · 2010
Researchers exposed Fasciola hepatica eggs to a 50 Hz, 2 mT extremely low frequency magnetic field for 10 days. The exposed eggs hatched faster than non-exposed control eggs. Snails infected with miracidia from exposed eggs laid significantly fewer cocoons by day 14 and showed significantly higher mortality by day 42 compared to control snails.
Unknown authors · 2010
The study used RAW 264.7 cells and RBL 2H3 cells. The cells were exposed to 60 Hz EMF at 0.1 or 1 mT for 4 or 16 hours. Basal and melittin-induced arachidonic acid release, cPLA2, sPLA2, PLC, and PLD activities were unchanged by EMF exposure. The authors concluded that the exposure conditions, which were 2.4 fold higher than the occupational limit, did not induce phospholipase-associated signaling pathways.
Ciejka E, Skibska B, Kleniewska P, Goraca A. · 2010
Researchers studied the influence of a low-frequency magnetic field on oxidative stress markers in rat muscles. Thirty male rats weighing 280 to 300 grams were randomly divided into three experimental groups, each containing seven animals. One treatment group was exposed to 40 Hz and 7 mT for 0.5 hours per day for 14 days, and the other was exposed at the same settings for 1 hour per day for 14 days. Exposure caused a significant increase in sulfhydryl group concentration and a decrease in protein concentration in the muscle homogenates.
Carrubba S, Frilot C 2nd, Chesson AL Jr, Marino AA · 2010
Researchers recorded EEGs from six standard locations in 20 volunteers to detect brain potentials triggered by a pulse of the type produced by mobile phones. Evoked potentials having the expected latency were found in 90% of the volunteers, as assessed using a nonlinear method of EEG analysis. Evoked potentials were not detected when the EEG was analyzed using time averaging. The possibility of systematic error was excluded by sham-exposure analyses.
Cuccurazzu B et al. · 2010
The exposure significantly enhanced neurogenesis in the dentate gyrus, with increased numbers of cells labeled for markers of new and developing neurons. Roughly half of the newly generated neurons survived 30 days after stimulation and became mature neurons integrated into the granule cell layer. The new mature neurons were associated with increased long-term potentiation, indicating an influence on hippocampal synaptic plasticity.
Kumar S, Jain S, Behari J, Avelev VD, Mathur R. · 2010
Researchers studied the effect of magnetic field exposure on food intake, water intake, and body weight in rats with complete spinal cord injury. Exposure ran at 50 Hz and 17.9 T for 2 hours per day over 8 weeks in rats with complete spinal cord transection at the T13 level. The results suggest a significant beneficial effect of chronic exposure to magnetic field of paraplegic rats.
Szemerszky R, Zelena D, Barna I, Bárdos G. · 2010
Researchers exposed adult male Sprague-Dawley rats to 50 Hz electromagnetic fields at 0.5 mT, either for 5 days at 8 hours daily or for 4 to 6 weeks at 24 hours daily. Neither exposure duration produced the body changes associated with chronic stress, such as body weight reduction, thymus involution, or adrenal gland hypertrophy. After long-term exposure, rats showed elevated proopiomelanocortin and depressive-like behavior, and blood glucose was also higher. The researchers noted that the exposure intensity used was much higher than typical human exposure.
Frahm J, Mattsson MO, Simkó M. · 2010
Researchers exposed mouse macrophages to a 50 Hz, 1.0 mT magnetic field and measured changes in reactive oxygen species production and protein expression. Short-term exposures of two hours or less caused slight and transient decreases in several proteins, including clathrin, adaptin, PI3-kinase, protein kinase B, and PP2A, while longer exposures had no effect on these proteins. The stress proteins Hsp70 and Hsp110 showed increased levels at certain time points but not generally.
Garip AI, Akan Z. · 2010
Researchers investigated the effect of ELF-EMF on apoptosis in K562 human leukemia cells, with and without oxidative stress, and examined links to heat-shock protein 70 levels. ELF-EMF at 1 mT and 50 Hz was applied for 3 hours, with one group of cells treated with H2O2 to induce oxidative stress and another left untreated. In cells not exposed to oxidative stress, ELF-EMF caused a decrease in the number of apoptotic cells and a slight increase in viability. In cells treated with H2O2, ELF-EMF increased the number of apoptotic cells, and hsp70 and reactive oxygen species levels were also increased.
Lee HM et al. · 2010
Researchers cultured human intervertebral disc (IVD) cells in alginate beads and exposed them to an electromagnetic field at 1.8 millitesla magnetic flux density and 60 Hz. Cellular proliferation was observed in the EMF group (p < 0.05), and no cytotoxicity was found. There was no significant change in the expression of aggrecan, type I, and type II collagen mRNA in the EMF group compared to the control group. DNA synthesis was partially mediated by nitric oxide and prostaglandin E2.
Mannerling AC, Simkó M, Mild KH, Mattsson MO · 2010
Researchers exposed human K562 leukemia cells to a 50-Hz sine-wave magnetic field for 1 hour at flux densities ranging from 0.025 to 0.10 mT, measuring proliferation, cell cycle distribution, superoxide radical anion levels, and HSP70 protein levels. Both vertical and horizontal exposures caused significantly and transiently increased HSP70 levels of more than twofold at several flux densities, compared to sham controls and also compared to a heat-treatment positive control. Superoxide radical anion levels increased by 30–40%, and adding free radical scavengers melatonin or 1,10-phenantroline inhibited the magnetic-field-induced increase in HSP70. Cell cycle kinetics and proliferation were not affected by exposure at 0.10 mT for 1 hour.
Morabito C et al. · 2010
Researchers used C2C12 cells as an in vitro model of the skeletal muscle phenotype to study the effects of short-term exposure to extremely low frequency electromagnetic fields on muscle cell differentiation and function. ELF-EMFs induced reactive oxygen species production in myoblasts and myotubes with a concomitant decrease in mitochondrial membrane potential. The cellular detoxification system was activated, with increases in catalase and glutathione peroxidase activities. ELF-EMFs also altered intracellular calcium homeostasis, increasing the spontaneous activity of myotubes and enhancing cellular reactivity to a depolarizing agent or an agonist of intracellular store calcium channels.
Cuccurazzu B et al. · 2010
Italian researchers exposed mice to 50 Hz electromagnetic fields (European power line frequency) for up to seven hours daily over one week. This significantly increased new brain cell growth in the hippocampus, improving long-term memory formation and suggesting potential therapeutic applications for brain regenerative medicine.
Szemerszky R, Zelena D, Barna I, Bárdos G. · 2010
Researchers exposed rats to 50 Hz electromagnetic fields (household electrical frequency) for weeks and found increased blood sugar, stress hormones, and depression-like behavior compared to short-term exposure. This suggests chronic EMF exposure may act as a mild stressor affecting mood and metabolism.
Volkow ND et al. · 2010
Researchers measured brain glucose metabolism in fifteen healthy subjects inside a 4 T magnet, comparing conditions with and without echo-planar imaging (EPI) gradient pulses. Relative metabolism was lower in areas at the poles of the brain when the EPI pulses were on compared to when they were off. The size of the metabolic decreases was significantly correlated with the estimated strength of the electric field (r = 0.68, p < 0.0001), such that a stronger field was associated with larger decreases. No differences were detected between the ON and OFF conditions for mood ratings or for absolute whole-brain metabolism.
Jorge-Mora T et al. · 2010
Markkanen A, Naarala J, Juutilainen J · 2010
Murine L929 fibroblast cells were exposed to 50 Hz magnetic fields of 100 or 300 μT during or before UV exposure. No significant magnetic field effects were found, and the results did not support the hypothesis that such fields modify biological responses to UV radiation by changing oxidative reactions.
Unknown authors · 2010
Turkish researchers exposed 120 mice to 50 Hz magnetic fields at various intensities (1-5 microTesla) for 40 days to test for genetic damage. They found no significant genotoxic effects, though some cellular changes occurred at higher exposure levels. The study concluded that power line frequency magnetic fields at these intensities don't cause genetic damage in mice.