Jouni FJ, Abdolmaleki P, Ghanati F. · 2012
Researchers studied whether a static magnetic field affects oxidative stress in Vicia faba plants grown in soil from a high background natural radioactivity area of Iran. Plants were continuously exposed to a static magnetic field of 15 mT for 8 days, each 8 hours per day. Antioxidant enzyme activity and flavonoid content were lower in plants from both high and low natural radioactivity soils compared to the control. The results suggest that static magnetic field exposure causes accumulation of reactive oxygen species, and that natural radioactivity of soil exaggerates oxidative stress.
Bułdak RJ et al. · 2012
Researchers assessed how cisplatin and an extremely low frequency electromagnetic field (ELF-EMF) affected antioxidant enzyme activity, lipid peroxidation, DNA damage, and reactive oxygen species (ROS) production in AT478 carcinoma cells. Cells were cultured with cisplatin for 24 and 72 hours and irradiated with 50 Hz/1 mT ELF-EMF for 16 minutes using a solenoid. When ELF-EMF was combined with cisplatin, ROS levels, antioxidant enzyme activity, and DNA damage all decreased compared to cisplatin alone, but ELF-EMF by itself increased DNA damage relative to control cells.
Rageh MM, El-Gebaly RH, El-Bialy NS. · 2012
Researchers exposed newborn rats continuously to a 50 Hz, 0.5 mT extremely low-frequency magnetic field for 30 days, starting when the rats were 10 days old. DNA damage in brain cells, measured by comet assay, was significantly higher in the exposed group. Exposure was associated with a significant four-fold increase in micronucleus induction and about a three-fold increase in mitotic index in bone marrow cells. Exposed rats also showed significantly higher levels of MDA and SOD, while ELF-MF failed to alter the activity of GSH.
Khalil AM, Gagaa M, Alshamali A. · 2012
Researchers exposed adult male Sprague-Dawley rats to mobile phone radio frequency radiation from a GSM signal generator at a whole-body specific absorption rate of 1.0 W/kg for 2 hours. Urinary levels of 8-oxodG, described as one major form of oxidative DNA damage, were significantly elevated in exposed rats compared to controls at most time points.
Cogulu O. · 2012
Researchers exposed mouse brain cell cultures to radiofrequency waves to evaluate genotoxic effects. The cultures were exposed to 10.715 GHz signals at a specific absorption rate of 0.725 W/kg for 6 hours over 3 days at 25°C. The study measured changes in the micronucleus assay and in the expression of 11 proapoptotic and antiapoptotic genes. The micronuclei rate increased 11-fold and STAT3 expression decreased 7-fold in the exposed cell cultures.
Chen G, Lu D, Chiang H, Leszczynski D, Xu Z. · 2012
Researchers used the yeast Saccharomyces cerevisiae to study how exposure to extremely low frequency magnetic fields and radiofrequency EMF affects gene expression. Yeast cells were exposed for 6 hours to either 0.4 mT 50 Hz ELF-MF or 1800 MHz RF-EMF at a specific absorption rate of 4.7 W/kg. The study found no confirmed gene expression changes from ELF-MF exposure, and only the expressions of SMC3 and AQY2 were confirmed as responsive to RF-EMF.
Unknown authors · 2011
Unknown authors · 2011
Researchers exposed human SH-SY5Y neuroblastoma cells to 50 Hz magnetic fields at 100 µT for 24 hours followed by chemical exposure for 3 hours. The chemicals used were menadione and methyl methanesulphonate to induce DNA damage and micronucleus formation. Pre-treatment with magnetic fields enhanced menadione-induced DNA damage, DNA repair rate, and micronucleus formation. Similar effects were seen with methyl methanesulphonate but were not statistically significant. No effects were observed from magnetic field exposure alone.
Unknown authors · 2011
Researchers exposed E. coli GE499 cells to a combination of static and extremely low frequency magnetic fields and measured chromatin conformation using the anomalous viscosity time dependence technique, as well as cell growth, cloning efficiency, and SOS response. Nalidixic acid at 3-30 μg/ml decreased AVTD peaks, caused cytotoxic effects, and induced SOS response. ELF exposure increased AVTD, stimulated cell growth, and increased cloning efficiency, with these effects depending on frequency within the 7-11 Hz range. ELF exposure did not induce the recA-lacZ fusion and did not modify the genotoxic effects of nalidixic acid. The article was retracted in 2014, with a retraction notice in Mutat Res Genet Toxicol Environ Mutagen on January 15, 2014.
Unknown authors · 2011
Researchers exposed two Escherichia coli model systems to sinusoidal (SiMF) or pulsed-square wave (PMF) magnetic fields of various frequencies (20, 50, 75 Hz) and for different exposure times (15 and 90 min). Transposition of both mini-Tn10 and Tn5 decreased under SiMF and increased under PMF compared to sham exposure control. No significant difference was found between frequencies and between exposure times.
Verschaeve L et al · 2011
Researchers performed a genotoxicity investigation of extremely low-frequency magnetic fields at 50 Hz, 100 and 500 µT, for 1 and 2 hours exposure, alone and with chemical mutagens using the VITOTOX test. The study showed that ELF magnetic fields do not induce SOS-based mutagenicity in S. typhimurium and do not show any synergetic effect when combined with chemical mutagens.
Unknown authors · 2011
Researchers assessed ELF-MF exposure in 21 welders using personal dosimeters and compared micronuclei and sister chromatid exchange frequencies in their lymphocytes to 21 matched controls. The exposed welders had a significantly higher micronuclei frequency (6.10±0.39) than controls (4.45±0.30), and this increase showed a dose-response relationship with ELF-MF exposure levels. Sister chromatid exchange frequency was significantly lower in exposed welders (3.73±0.21) than in controls (4.89±0.12). Replication indices did not differ between exposed and control groups. The authors concluded that the correlation between genotoxic assays and ELF-MF exposure was partially supported, especially for micronuclei, and recommended a larger study.
Unknown authors · 2011
Researchers exposed female NMRI mice to a 50-Hz, 0.5 mT electromagnetic field for four hours per day, six days a week over two weeks. After eight days of exposure, the mice were superovulated with hormone injections, mated overnight, and blastocysts were flushed from the uterus at about four days post-mating. The exposed group had significantly fewer blastocysts than controls. DNA fragmentation in blastocyst cells was significantly higher in the exposed group (10.53% vs 7.14%). The numbers of blastomeres and pregnant mice did not differ significantly between groups.
Le Quement C et al · 2011
Researchers exposed primary human skin cells to 60.4 GHz radiation at 1.8 mW/cm² for 1, 6, or 24 hours. They used gene expression microarrays with over 41,000 probes to compare exposed and sham cells. No significant gene expression differences were found using the Benjamini-Hochberg procedure. A t-test identified 130 potentially modulated transcripts. Real-time PCR on 24 selected genes confirmed five genes (CRIP2, PLXND1, PTX3, SERPINF1, TRPV2) as differentially expressed after 6 hours.
Unknown authors · 2011
The authors reviewed published reports on DNA responses to electromagnetic fields across different frequency ranges and characterized DNA's properties as an antenna. They examined reports of increased stress protein levels and DNA strand breaks from EMF interactions, both indicating DNA damage. EMF interactions with DNA were found to be similar across non-ionising frequencies including extremely low frequency and radio frequency ranges. DNA was concluded to possess the structural characteristics of fractal antennas: electronic conduction and self symmetry.
Unknown authors · 2011
Researchers studied mitotic spindle disturbances and apoptosis activation in V79 Chinese hamster cells exposed to continuous 2.45 GHz microwaves to investigate non-thermal cell damage. Exposure for 15 minutes significantly increased the proportion of aberrant spindles and apoptotic cells and decreased the mitotic index compared with untreated cells. Control heating experiments showed that spindle assembly was unaffected up to 41°C and apoptosis occurred only at 40°C, a temperature higher than that reached during microwave exposure.
Unknown authors · 2011
In vitro studies used several cell types from both humans and rodents, including primary cells, embryonic cell lines, undifferentiated cancer cell lines, and stem cells. Gene and protein expression were not significantly changed by exposure in nine out of 15 studies. Genotoxicity was evaluated in 13 papers and in most of these studies no DNA damage was detected; eight studies failed to demonstrate induction of apoptosis and three reported lack of oxidative stress induction by RF exposures. Few papers have been published on low level exposure of immature animals and the available results are very limited, but the evidence does not indicate that prenatal or early postnatal exposures are associated with acute adverse responses or long-term detrimental changes.
Roux D et al. · 2011
Redmayne M, Smith E, Abramson MJ. · 2011
Researchers explored school cellphone rules and adolescent exposure to cellphone microwave emissions during school using a census and survey. All schools banned private use of cellphones in class, but 43% of student participants admitted breaking this rule. A high-exposure group of risk-takers was identified for whom prohibited in-school use was positively associated with high texting rates, carrying the phone switched-on >10h/day, and in-pocket use. The authors reviewed reproductive bio-effect papers and concluded there is sufficient evidence and expert opinion to warrant an enforced school policy removing cellphones from students during the day.
Bourthoumieu S et al. · 2011
Researchers investigated the potential induction of genomic instability by GSM-900 MHz radiofrequency radiation in human amniotic cells exposed for 24 h to average-specific absorption rates (SAR) of 0.25, 1, 2 and 4 W/kg. The rate of aneuploidy of chromosomes 11 and 17 was determined by interphase FISH immediately after independent exposure of three different donors for 24 h. No significant change in the rate of aneuploidy of chromosomes 11 and 17 was found at average SAR up to 4 W/kg.
Sakurai T et al. · 2011
The study used DNA microarray to examine gene expression in SVGp12 human glial cells after exposure to 2.45 GHz continuous-wave RF fields at SARs of 1, 5, and 10 W/kg for 1, 4, and 24 hours. Microarray analysis identified 23 assigned and 5 non-assigned gene spots as potentially altered. Follow-up RT-PCR analysis of Twenty-two genes showed no significant alterations in gene expression. The authors concluded that under their experimental conditions they found no evidence that RF field exposure affected gene expression in SVGp12 cells.
Chaturvedi CM et al. · 2011
Garaj-Vrhovac V et al. · 2011
The study examined workers occupationally exposed to pulsed microwave radiation from marine radars. Comet assay parameters (mean tail intensity 0.67 vs 1.22, moment 0.08 vs 0.16) and micronucleus test parameters showed statistically significant differences between exposed and unexposed groups. Glutathione concentration was significantly lower in exposed workers (1.24 vs 0.53) while malondialdehyde concentration was significantly higher (1.74 vs 3.17), indicating oxidative stress. Electromagnetic field strength was measured at marine radar frequencies of 3 GHz, 5.5 GHz, and 9.4 GHz with specific absorption rate values determined.
Sannino A et al. · 2011
Researchers exposed human peripheral blood lymphocytes in G0, G1, or S-phase to 900 MHz RF at 1.25 W/kg for 20 hours, then treated them with mitomycin C. The incidence of micronuclei was evaluated to determine adaptive response. Cells exposed in S-phase showed an adaptive response, while those exposed in G0 or G1 did not.
Lee JW, Kim MS, Kim YJ, Choi YJ, Lee Y, Chung HW. · 2011
Researchers investigated the genotoxic potential of 3 T clinical MRI scans in cultured human lymphocytes by exposing them to electromagnetic fields from a clinical brain protocol for 22, 45, 67, and 89 minutes. They observed a significant increase in single-strand DNA breaks after exposure. Micronuclei and chromosome aberration frequencies increased in a time-dependent manner.
