Kim J, Yoon Y, Yun S, Park GS, Lee HJ, Song K · 2012
Researchers investigated the genotoxic effect of a time-varying magnetic field on human primary fibroblasts and cervical cancer cells. Continuous exposure to a 60 Hz, 7 mT magnetic field for 10-60 minutes did not change cell viability but induced DNA double-strand breaks and activated the DNA damage checkpoint pathway without apoptosis. The exposure did not increase intracellular reactive oxygen species, suggesting the DNA breaks were not directly caused by ROS.
Hintzsche H et al. · 2012
Researchers exposed cells to terahertz electromagnetic fields for 2 h, 8 h, and 24 h at power intensities from 0.04 mW/cm2 to 2 mW/cm2. Genomic damage was assessed using the comet assay for DNA strand breaks and alkali-labile sites and the micronucleus assay for chromosomal damage. No DNA strand breaks or alkali-labile sites were detected after exposure. The fields also did not induce micronucleus formation, indicating no chromosomal damage.
Huwiler SG et al · 2012
No changes in bacterial growth or culturable counts were observed for any of the magnetic field types. Gene expression analysis of 4,358 genes and 714 intergenic regions showed no statistically significant changes after exposures of 2.5 hours or 15 hours.
Unknown authors · 2012
Researchers exposed female Fischer 344 and Lewis rats to a 50 Hz, 100 μT magnetic field for two weeks. Whole genome microarray analysis of mammary gland tissue revealed decreased α-amylase, carbonic anhydrase 6, and lactoperoxidase gene expression, and increased cystatin E/M expression in exposed F344 rats but not in Lewis rats.
Unknown authors · 2012
Researchers used an in vitro retrotransposition assay on human neuroblastoma BE(2) cells exposed for 48h to 1mT, 50Hz PMF or sham exposure. They also measured γ-H2AX foci as a marker of DNA DSB in both exposed and sham-exposed samples. PMF-exposed cells had a lower number of both retrotransposition events and DNA DSB compared with sham-exposed samples.
Unknown authors · 2012
Unknown authors · 2012
Seventeen pairs of male volunteers aged 20-30 were exposed to a 50 Hz electromagnetic field at 62.0 ± 7.1 μT for two hours or to a sham exposure at 0.21 ± 0.05 μT. The exposure sequence was repeated the next day and again six days later with a null exposure of 0.085 ± 0.01 μT replacing the sham. Researchers examined 16 genes previously reported to respond to ELF-EMF exposure using Illumina microarrays on pooled RNA samples. No genes or gene sets showed consistent response profiles to the repeated ELF-EMF exposures. A transient cortisol increase occurred at the onset of both exposure and sham on the first day, diminishing over subsequent sessions and attributed to protocol-related stress.
Unknown authors · 2012
A wide range of EMF frequencies has been linked to an increased risk of cancer. The SAR value used for radiofrequency safety standards fails to predict cancer risk in the ELF power frequency range. Because cancers are believed to arise from mutations in DNA, changes in DNA induced by EMF interaction could be a better measure of biologically effective dose in both frequency ranges. Such DNA changes can be measured by transcriptional alterations and/or translational changes in specific proteins.
Unknown authors · 2012
Researchers conducted a meta-analysis of 88 peer-reviewed publications from 1990 to 2011 assessing genetic damage in human cells exposed to radiofrequency fields. The analysis examined five exposure variables: frequency, specific absorption rate, exposure type, duration, and cell type. The magnitude of difference between RF-exposed and control cells was small with some exceptions. Statistically significant increases in genotoxicity were observed in some endpoints under certain conditions, but these effects were seen in studies with small sample sizes and were largely influenced by publication bias. Studies within recommended exposure guidelines showed smaller effects, and mean indices for chromosomal aberrations, micronuclei, and sister chromatid exchange were within spontaneous levels.
Ros-Llor I et al. · 2012
Researchers conducted a cohort study of 50 Caucasian mobile phone users, collecting two cheek mucosa cell samples from each participant. No statistically significant changes were recorded for age, gender, body mass index, or smoking status, and comparisons by phone side and exposure duration showed no significant differences. The authors reported no genotoxic effects from RF exposure for any study parameter.
Hintzsche H et al. · 2012
Bourthoumieu S et al. · 2012
Researchers exposed human amniotic cells to GSM-900 radiofrequency fields for 24 hours at SARs of 0.25, 1, 2, and 4 W/kg. They measured p53 protein expression and phosphorylation at serine 15 and 37 using Western blot after three independent exposures from three donors. No significant changes in p53 expression or activation were found at any of the tested SARs up to 4 W/kg in human embryonic cells. Bleomycin-exposed cells served as a positive control.
Vannoni D et al. · 2012
Researchers cultured isolated human osteoarthritic chondrocytes in vitro, some stimulated with IL-1beta or IGF-1 to mimic osteoarthritis imbalance. The cells were exposed to extremely low frequency (100 Hz) electromagnetic fields and to Therapeutic Application of Musically Modulated Electromagnetic Fields (TAMMEF) with variable frequencies, intensities, and waveforms. Using flow cytometry, they tested effects on chondrocyte metabolism. Exposure to both systems enhanced cell proliferation and did not generate reactive oxygen species, cause glutathione depletion, change mitochondrial transmembrane potential, or induce apoptosis.
Jin YB et al. · 2012
Researchers exposed mouse NIH3T3 and human WI-38 fibroblast cells to a 60 Hz, 1 mT magnetic field for 4 hours, with or without ionizing radiation, hydrogen peroxide, or c-Myc activation. Cells exposed to the magnetic field alone showed no significant difference in micronucleus frequency compared to unexposed cells. No synergistic effects were observed when the magnetic field was combined with ionizing radiation, hydrogen peroxide, or c-Myc activation.
Trivino Pardo JC, Grimaldi S, Taranta M, Naldi I, Cinti C. · 2012
Researchers cultured acute T-lymphoblastoid leukemia cells (CCRF-CEM) and exposed them to 900 MHz microwave EMF from a TEM cell at short and long exposure times. They evaluated the effect of high-frequency EMF on gene expression and identified functional pathways influenced by the exposure.
Panagopoulos DJ · 2012
Researchers studied the effect of GSM radiation on ovarian development in virgin Drosophila melanogaster females. Exposed insects had significantly smaller ovaries due to destruction of egg chambers from DNA damage and cell death. The ovarian size difference peaked at 39-45 hours after eclosion and then decreased as mature eggs were laid in sham-exposed flies.
Miller G, Zhu G, Wright MJ, Hansell NK, Martin, NG · 2012
Researchers analyzed self-reported mobile phone use, intelligence, and personality traits in two samples of Australian teenaged twins totaling 1,036 individuals. ACE modeling showed substantial heritabilities for voice call frequency (.60 and .34) and text message frequency (.53 and .50), while shared family environment had much weaker effects. Multivariate modeling revealed negative genetic correlations between talking/texting frequency and intelligence (around -.17) and positive genetic correlations with extraversion (about .20 to .40).
Avendaño C, Mata A, Sanchez Sarmiento CA, Doncel GF. · 2012
Researchers exposed sperm from 29 healthy donors to a Wi-Fi-connected laptop for four hours. Exposed sperm had significantly lower progressive motility and more DNA fragmentation than unexposed sperm. Sperm viability did not differ between groups.
Cam ST, Seyhan N. · 2012
Researchers collected hair samples from eight healthy human subjects before and after they used a 900-MHz GSM mobile phone for 15 and 30 minutes. Single-strand DNA breaks in hair root cells were measured using the comet assay. Both exposure durations significantly increased DNA single-strand breaks, and the 30-minute exposure caused significantly more damage than the 15-minute exposure.
Zeni O et al. · 2012
When lymphocytes from six donors were pre-exposed to RF at 0.3W/kg SAR and then treated with MMC, these cells showed a significant reduction in the frequency of MN compared with cells treated with MMC alone, indicating adaptive response. An earlier study found that lymphocytes stimulated for 24h, exposed for 20h to a 900MHz RF GSM signal at 1.25W/kg SAR and then treated with 100ng/ml MMC also exhibited adaptive response. In the current study, cells from nine healthy human volunteers were stimulated for 24h with phytohaemagglutinin, exposed for 20h to a 1950MHz RF UMTS signal at SARs of 1.25, 0.6, 0.3, and 0.15W/kg, then treated at 48h with 100ng/ml mitomycin C, and micronuclei frequency was recorded at 72h using the cytokinesis-block method.
Sekeroğlu V, Akar A, Sekeroğlu ZA · 2012
Researchers investigated the cytogenotoxic effects of 1800 MHz electromagnetic fields on bone marrow cells of immature and mature rats over 45 days with a 15-day recovery period. Significant differences were observed in chromosome aberrations, micronucleus frequency, mitotic index, and polychromatic erythrocyte ratio in all treatment groups. A 15-day recovery period did not improve the cytogenotoxic damage in immature rats.
Kumar S, Behari J, Sisodia R. · 2012
Researchers exposed 70-day-old male Wistar rats to 10 GHz microwave radiation for 2 h per day for 45 days at power density 0.21 mW/cm(2) and SAR of 0.014 W/kg, with a sham-exposed control group. Scanning electron microscopy revealed shrinkage of the seminiferous tubule lumen, and apoptotic bodies were present in the exposed group. Flow cytometry showed micronuclei formation in lymphocytes, comet assay confirmed DNA strand breaks, and testosterone levels were significantly decreased alongside testicular shrinkage.
Hekmat A, Saboury AA, Moosavi-Movahedi AA. · 2012
Researchers exposed calf thymus DNA to mobile phone radiofrequency fields at 940 MHz, 15 V/m, and a SAR of 40 mW/kg, then examined the DNA immediately after exposure and again two hours after a 45-minute exposure using several laboratory instruments. UV-vis and circular dichroism experiments showed that the EMFs caused disturbance in the DNA structure. Exposed DNA samples were relatively thermally unstable compared to unexposed DNA, and showed more fluorescence emission, which the researchers suggested may have occurred due to expansion of the exposed DNA structure. The structure of the DNA immediately after exposure was not significantly different from the DNA sample two hours after the 45-minute exposure, suggesting the changes were irreversible.
Jiang B, Nie J, Zhou Z, Zhang J, Tong J, Cao Y. · 2012
Researchers pre-exposed mice to 900 MHz radiofrequency fields at 120 µW/cm2 for 4 hours per day for 1, 3, 5, 7, or 14 days, then subjected them to an acute dose of 3 Gy of gamma-radiation. DNA damage in peripheral blood leukocytes was measured using the alkaline comet assay, which detects alkali labile base damage and single strand breaks. Mice pre-exposed to radiofrequency fields for just 1 day showed damage similar to those exposed to gamma-radiation alone, but pre-exposure for 3 or more days led to progressively decreased damage.
Güler G et al. · 2012
Researchers exposed infant rabbits to 1800 MHz GSM-like RF radiation and measured lipid peroxidation and DNA damage in their livers. Lipid peroxidation levels in liver tissue increased in both female and male infant rabbits under RF radiation exposure. Liver 8-OHdG levels, a marker of DNA damage, increased in exposed female rabbits but showed no change in exposed male rabbits. The researchers concluded that GSM-like RF radiation may induce biochemical changes by increasing free radical attacks to structural biomolecules in the rabbit model.