Zeng Y, Shen Y, Hong L, Chen Y, Shi X, Zeng Q, Yu P · 2017
Researchers evaluated the biological effects of different patterns of extremely low frequency magnetic field exposure on primary cultured hippocampal neurons, looking at viability, apoptosis, genomic instability, and oxidative stress. Repeated exposure to a 50-Hz 2-mT field for 8 hours per day decreased cell viability and increased the production of intracellular reactive oxygen species. The researchers noted that none of the repeated exposure patterns had significant effects on DNA damage, apoptosis, or autophagy, suggesting no severe biological consequences in the cultured neurons.
Solek P et al. · 2017
Researchers investigated the effects of pulsed and continuous electromagnetic fields on two mouse spermatogenic cell lines, GC-1 spg and GC-2 spd, in vitro. The researchers evaluated mitochondrial metabolism, morphology, proliferation rate, viability, cell cycle progression, oxidative stress balance, and regulatory proteins. The results strongly suggested that EMF induced oxidative and nitrosative stress-mediated DNA damage, resulting in p53/p21-dependent cell cycle arrest and apoptosis. The researchers concluded that electromagnetic field impairs male fertility by inducing p53/p21-mediated cell cycle arrest and apoptosis.
Pooam M, Nakayama M, Nishigaki C, Miyata H · 2017
Researchers exposed RAW264 macrophage cells to a 50-Hz sinusoidal magnetic field at 0.1 mT or 0.5 mT and measured superoxide production, HSP70 expression, and mitochondrial membrane potential. The magnetic field enhanced production of superoxide and the expression of HSP70. The researchers suggested that the 50-Hz magnetic field diminished mitochondrial membrane potential, which led to increased superoxide production and HSP70 expression.
Naarala J et al. · 2017
Researchers studied how the direction of combined static and extremely low frequency (ELF) magnetic fields affected cell proliferation and superoxide radical production. Proliferation of human umbilical vein endothelial cells was stimulated by a nearly vertical 60 or 120 μT static magnetic field compared with cells that were shielded against magnetic fields. When the static field was combined with an extremely low frequency ELF field, proliferation was suppressed by a horizontal but not by a vertical ELF field.
Miao X et al. · 2017
Researchers conducted a preclinical randomized study using 3-week-old male BALB/c mice repeatedly exposed to electromagnetic pulses at a peak intensity of 200 kV/m, 5 days per week for four consecutive weeks. Some mice also received daily co-administration of selenium-rich Cordyceps fungi at 100 mg/kg. Mice exposed without Cordyceps showed decreased sperm formation, shrunk seminiferous tubule diameters, and diminished antioxidative capacity at 28 and 60 days after exposure. Daily Cordyceps co-treatment alleviated the testicular damage, increased sperm formation, and reduced apoptotic spermatogenic cells.
Medina-Fernandez FJ et al. · 2017
Researchers injected rats with a single dose of 150 μg of myelin oligodendrocyte glycoprotein (MOG, fragment 35–55) to produce experimental multiple sclerosis. The MOG injection caused motor symptoms such as tail paralysis and limb paresis/paralysis, along with oxidative stress and cell death similar to MS. Rats were then treated with extremely low-frequency electromagnetic fields applied as transcranial magnetic stimulation (TMS) at 60 Hz and 0.7 mT for 2 hours a day, once a day, 5 days a week, for 3 weeks. The researchers found that TMS attenuated motor symptoms and oxidative and cell damage, and also increased the antioxidant system.
Kim SJ et al. · 2017
Researchers examined the effects of 60 Hz 0.8 mT extremely low-frequency electromagnetic fields on a macrophage cell line called RAW 264.7. Under ELF-EMF exposure, production of nitric oxide and pro-inflammatory cytokines TNF-α, IL-1β, and IL-6 were increased, and the expression of those genes was also upregulated. Cell proliferation was not altered by ELF-EMF exposure. The researchers suggest that ELF-EMF amplifies inflammatory responses through enhanced macrophage activation and can decrease the effectiveness of antioxidants.
Kamalipooya S et al. · 2017
Researchers studied the effects of combining a static magnetic field (SMF) with the anticancer drug cisplatin on oxidative stress in human cervical cancer cells (HeLa) and normal skin fibroblast cells (Hu02). Cells were exposed to SMF intensities of 7, 10, and 15 mT for 24 and 48 hours, and cytotoxic effects were measured using reactive oxygen species content and membrane lipid peroxidation. The combination of both treatments for 48 hours led to a marked decrease in HeLa cell viability of about 89% compared to untreated cells. The study suggests that among the optional intensities of SMF tested, the intensity of 10 mT led to higher damage to cancer cells at lower doses of the drug.
Höytö A, Herrala M, Luukkonen J, Juutilainen J, Naarala J. · 2017
Researchers exposed human SH-SY5Y neuroblastoma cells to a 50 Hz, 100 μT magnetic field with or without a non-phototoxic level of blue light for 24 hours. The magnetic field increased cytosolic superoxide production, while blue light suppressed that effect. Mitochondrial superoxide production was reduced by both the magnetic field and blue light, but these effects were not additive. Micronucleus frequency was not affected by blue light or the magnetic field alone, but blue light, significantly when combined with the magnetic field, enhanced menadione-induced micronuclei.
Hanini R, Chatti A, Ghorbel SB, Landoulsi A. · 2017
Researchers studied the protective role of superoxide dismutase (SOD) against a static magnetic field of 200 mT in wild-type and mutant strains of Pseudomonas aeruginosa lacking one or both SOD enzymes. Inactivation of the sodM and/or sodB genes increased the sensitivity of the bacteria to stress from the static magnetic field. Mutant strains also showed significantly higher levels of malondialdehyde, a marker of oxidative damage to lipids, compared to wild-type cells.
Giorgi G et al. · 2017
Researchers exposed human neural cells (BE(2)C) to an extremely low frequency pulsed magnetic field (50 Hz, 1 mT) for 24 and 48 hours, alone and combined with oxidative stress, to study DNA methylation changes. Exposure to the magnetic field alone or oxidative stress alone produced only weak changes in DNA methylation levels at different CpG sites. When the two exposures were combined, a significant decrease in DNA methylation levels was found at different CpG sites, and most of those changes were transient.
Falone S et al. · 2017
Researchers investigated whether a 50 Hz, 1 mT ELF magnetic field promoted hyperproliferation and improved defence against reactive oxygen species in SH-SY5Y human neuroblastoma cells. The field activated antioxidant and detoxification pathways linked to more aggressive cell behavior, along with upregulation of major sirtuins and increased NRF2 signaling. Exposure to a 50 Hz magnetic field as low as 100 µT may still be able to alter cancer cell behavior and responses to clinically relevant drugs.
Dornelles EB et al. · 2017
Researchers tested the in vitro cytotoxic effects of a 5 mT static magnetic field on human blood cells carrying different variants of the Val16Ala polymorphism in the manganese superoxide dismutase gene. Cytotoxic effects were observed in AA cells at all exposure times, while AV cells showed higher mortality only after 6 hours, and higher apoptosis induction was seen in AA cells compared to VV and AV cells. The authors suggest the results indicate a toxicogenetic effect of the static magnetic field related to an imbalance in SOD2 activity.
Djordjevic NZ, Paunović MG, Peulić AS · 2017
Researchers investigated whether short-term exposure to ELF-EMF at 50 Hz could produce anxiety-like behaviour in rats through changes in hypothalamic oxidative stress and nitric oxide. Ten adult male Wistar albino rats were divided into a control group with no exposure and an experimental group exposed to the field during 7 days, after which open field and elevated plus maze tests measured anxiety-like behaviour. The exposed rats showed anxiety-like behaviour and higher concentrations of superoxide anion and nitric oxide in the hypothalamus, while peroxynitrite concentration was not affected.
Cichoń N et al. · 2017
Patients were divided into two groups, both undergoing the same 4-week rehabilitation program, with one group also receiving daily ELF-EMF exposure. The ELF-EMF group was exposed to a field of 40 Hz and 7 mT for 15 minutes per day. ELF-EMF significantly increased 3-nitrotyrosine and nitrate/nitrite levels, while NOS2 expression was insignificantly decreased in both groups. The researchers concluded that ELF-EMF therapy is capable of promoting recovery in poststroke patients.
Cichoń N, Bijak M, Miller E, Saluk J. · 2017
Researchers investigated the effect of ELF-EMF on clinical and antioxidant status in post-stroke patients. Fifty-seven patients were divided into two groups: ELF-EMF and non-ELF-EMF, and both groups underwent the same 4-week rehabilitation program. The ELF-EMF group was additionally exposed to a field of 40 Hz, 7 mT for 15 min/day for 4 weeks, 5 days a week. ELF-EMF significantly increased enzymatic antioxidant activity, though total antioxidant status levels did not change in either group.
Calcabrini C et al. · 2017
Researchers investigated whether ELF-EMF exposure causes significant cell damage in human keratinocytes, to support potential ELF-EMF use in regenerative medicine for skin injuries. Reactive oxygen species production was evaluated in human keratinocytes exposed for 1 H to 50 Hz ELF-EMF at field strengths from 0.25 to 2 G, and significant ROS increases resulted at 0.5 and 1 G. All significant alterations observed in the first 4 H of exposure reverted to controls 24 H after, and the exposure did not have a cytotoxic effect.
Wang K et al. · 2017
Researchers examined the effects of a single 30-minute exposure to 1.8 GHz radiofrequency electromagnetic radiation on recognition memory in mice, using the novel object recognition task. Exposure at an intensity above 2.2 W/kg SAR produced a significant, density-dependent increase in the recognition memory index, with no corresponding changes in spontaneous locomotor activity. The researchers also found that exposure increased dendritic-spine density and length in hippocampal and prefrontal cortical neurons, and significantly altered neuronal excitability in pyramidal neurons. The SAR used in the study was 3.3 W/kg, which the researchers noted was outside the range encountered in normal daily life.
Wang H et al. · 2017
Researchers exposed 220 male Wistar rats to a 2.856 GHz radiation source at power densities of 0, 2.5, 5, and 10 mW/cm² for 6 min/day, 5 days/week, for up to 6 weeks. Rats in the 10 mW/cm² group showed declines in spatial learning and memory and EEG disorders, including decreased EEG frequencies and increased amplitudes and delta wave powers. Changes in the basic structure and ultrastructure of the hippocampus were found in the 10 and 5 mW/cm² groups. The researchers suggested that continuous microwave exposure could cause dose-dependent long-term impairment of spatial learning and memory, and that decreases in NMDAR key subunits and phosphorylation of NR2B might contribute to cognitive impairment.
Kim JH, Yu DH, Huh YH, Lee EH, Kim HG, Kim HR. · 2017
Researchers exposed C57BL/6 mice to 835 MHz RF-EMF at a specific absorption rate of 4.0 W/kg for 5 hours per day during 12 weeks. The study found that RF-EMF exposure led to myelin sheath damage and that mice displayed hyperactivity-like behavior. Autophagy-related proteins including LC3B-II and Beclin1 were increased in neuronal cell bodies, and the researchers suggest autophagy may act as a protective pathway during radiofrequency exposure.
Unknown authors · 2016
Researchers conducted a long-term field monitoring study from 2006 to 2015 in Bamberg and Hallstadt, Germany, to examine the connection between unusual tree damage and radiofrequency exposure. They measured radiofrequency electromagnetic fields at 144 locations and interpolated the points to compile an electromagnetic map of power flux density, and selected 60 damaged trees, 30 randomly selected trees, and 30 trees in low radiation areas for comparison. Measurements showed significant differences in power flux density between the damaged side facing a phone mast and the opposite side, and trees in low radiation areas showed no damage.
Unknown authors · 2016
Unknown authors · 2016
This case study of a Wisconsin dairy farm documents how to establish permanent monitoring of ground current and how to determine and remediate both on-farm and off-farm sources. On-farm sources included lighting, variable speed frequency drives on motors, and a radio frequency identification system, while off-farm sources were due to a poor primary neutral return on the utility side. The study found that a step-potential threshold of 1 V RMS at 60 Hz is inadequate to protect dairy cows, as decreases of a few mV peak-peak at higher frequencies increased milk production, reduced milking time, and improved cow comfort.
Unknown authors · 2016
Paknahad M, Mortazavi SM, Shahidi S, Mortazavi G, Haghani M · 2016
Researchers prepared class V cavities in 20 extracted human premolars and randomly divided them into two groups of 10. The experimental group was exposed to 2.4 GHz Wi-Fi radiation for 20 minutes at a distance of 30 cm while the router communicated with a laptop 20 meters away. Mercury concentration in artificial saliva was significantly higher in the exposed group (0.056 ± .025 mg/L) than in the control group (0.026 ± .008 mg/L) (P =0.009).
