Nylund R, Kuster N, Leszczynski D · 2010
Researchers exposed human blood vessel cells (endothelial cells) to cell phone radiation at 1800 MHz for one hour at levels similar to what phones emit during calls. They used advanced protein analysis to detect any changes in how the cells functioned. The study found no statistically significant changes in protein expression, suggesting this type of radiation exposure didn't alter cellular activity in these particular cells under these conditions.
Lee HJ et al. · 2010
Male rats were exposed to 848.5 MHz RF for 12 weeks. The exposure schedule consisted of two 45-min RF exposure periods separated by a 15-min interval. The whole-body average SAR was 2.0 W/kg. Researchers measured sperm counts, malondialdehyde concentrations, spermatogenesis stage frequency, germ cell counts, apoptotic cells, and performed immunoblotting for p53, bcl-2, caspase 3, p21, and PARP. The study concluded that subchronic exposure did not have observable adverse effects on rat spermatogenesis.
Falzone N, Huyser C, Franken DR, Leszczynski D. · 2010
Researchers examined effects of mobile phone radiation on apoptosis-related properties in human spermatozoa. Ejaculated, density-purified, highly motile human spermatozoa were exposed to mobile phone radiation at specific absorption rates of 2.0 and 5.7 W/kg. Mobile phone radiation had no statistically significant effect on any of the parameters studied, including caspase 3 activity, externalization of phosphatidylserine, DNA strand breaks, and reactive oxygen species generation. This suggests that impairment of fertility reported in some studies was not caused by induction of apoptosis in spermatozoa.
Zhijian C et al. · 2010
Researchers used a comet assay to study whether 1.8-GHz radiofrequency radiation (RFR, SAR of 2 W/kg) could influence DNA repair in human B-cell lymphoblastoid cells exposed to doxorubicin (DOX). RFR alone did not directly induce DNA damage in the cells. A specific combined-exposure pattern could obviously influence DNA repair at 6 h and 12 h after exposure to DOX for four DOX doses.
Gerner C et al. · 2010
Researchers used proteome analysis to study whether low-intensity radio-frequency electromagnetic field exposure could affect protein synthesis in cultured human cells. Four different cell types were exposed to 2 W/kg specific absorption rate, and autoradiography of 2D gel spots was used to measure changes in synthesis of individual proteins. An 8-hour exposure caused a significant increase in protein synthesis in Jurkat T-cells and human fibroblasts, and to a lesser extent in activated primary human mononuclear cells, while short-term exposure did not significantly alter the proteome. Quiescent, metabolically inactive mononuclear cells did not detectably respond to the exposure.
Xu S et al. · 2010
Researchers exposed brain neurons to cell phone radiation (1800 MHz) for 24 hours and found it damaged mitochondrial DNA-the genetic material in cells' energy centers. The radiation created harmful molecules that reduced neurons' ability to produce energy, suggesting potential cellular harm from prolonged exposure.
Kim KB et al. · 2010
Researchers exposed MCF7 human breast cancer cells to 849 MHz RF radiation for one hour per day over three consecutive days at SARs of 2 or 10 W/kg. Protein expression profiles were analyzed using two-dimensional gel electrophoresis and showed no significant or reproducible changes after exposure. Follow-up analysis of three non-reproducible protein spots using mass spectrometry, RT-PCR, and Western blot confirmed no alterations in mRNA or protein levels.
Zhijian C et al. · 2009
Researchers used the in vitro comet assay to determine whether 1.8-GHz radiofrequency radiation can influence DNA repair in human leukocytes exposed to X-rays. Leukocytes from four young healthy donors were intermittently exposed to RFR at a SAR of 2 W/kg for 24 hours with fields on for 5 minutes and off for 10 minutes, then irradiated with X-rays at doses of 0.25, 0.5, 1.0 and 2.0 Gy. DNA damage was measured at 0, 15, 45, 90, 150 and 240 minutes after X-rays using percent tail DNA, and repair speed was assessed via DNA repair percentage. The results showed individual differences in DNA repair speeds among the four donors. Intermittent RFR exposure did not directly induce DNA damage or show synergistic effects with X-rays.
Lee HJ, Lee JS, Pack JK, Choi HD, Kim N, Kim SH, Lee YS. · 2009
Researchers investigated the teratogenic effects of multi-signal radiofrequency electromagnetic fields on mouse fetuses. Pregnant mice were simultaneously exposed to CDMA and WCDMA signals for two 45-minute periods daily throughout gestation at a whole-body average SAR of 2.0 W/kg. Fetuses were examined on gestation day 18 for mortality, growth retardation, head size changes, and morphological abnormalities, and no adverse effects were observed.
Dimbylow PJ, Nagaoka T, Xu XG. · 2009
The study compared foetal specific absorption rate (SAR) across three sets of pregnant female computational models. The models included a 26-week foetal model from the National Institute of Information and Communications Technology, Tokyo, and models at 13, 26, and 38 weeks from Rensselaer Polytechnic Institute. FDTD calculations were performed at a resolution of 2 mm for a plane wave with a vertically aligned electric field incident upon the body from the front, back and two sides from 20 MHz to 3 GHz under isolated conditions. The researchers compared external electric field values required to produce the ICNIRP public exposure localized restriction of 2 W kg(-1) when averaged over 10 g of the foetus with the ICNIRP reference levels.
Zhang SZ, Yao GD, Lu DQ, Chiang H, Xu ZP. · 2008
Researchers exposed rat brain cells to cell phone radiation (1.8 GHz) for up to 24 hours. The radiation altered 34 genes controlling brain cell structure, communication, and metabolism. Changes were stronger with intermittent exposure patterns, suggesting cell phone signals may affect brain function.
Lee JJ et al. · 2008
NIH3T3 mouse fibroblasts were exposed to 849 MHz RF radiation at average SAR values of 2 or 10 W/kg for either 1 hour or 1 hour per day for 3 days. Cellular invasion and migration were assessed using in vitro Matrigel invasion and Transwell migration assays. Cell cycle distribution was analyzed at 24 and 48 hours after exposure by flow cytometry. The study found no detectable effects on cell cycle distribution, cellular migration, or invasion at the tested SAR values.
Zhang SZ, Yao GD, Lu DQ, Chiang H, Xu ZP. · 2008
Researchers exposed primary cultured rat neurons to 1.8 GHz RF EMF at a SAR of 2 W/kg and used a gene array to look for changes in gene expression. Among 1200 candidate genes screened, 24 were up-regulated and 10 were down-regulated, associated with functions including cytoskeleton, signal transduction, and metabolism. The effect of 24-hour exposure on gene expression was more obvious than that of 6-hour exposure, and intermittent exposure had a more obvious effect than continuous exposure.
Joubert, V., Bourthoumieu, S., Leveque, P. and Yardin, C. · 2008
Researchers exposed rat primary neuronal cultures to a continuous-wave 900 MHz radiofrequency field at a specific absorption rate of 2 W/kg for 24 hours. A statistically significant difference in the rate of apoptosis was found in the RF-field-exposed neurons compared to the sham-, 37°C- and 39°C-exposed neurons either 0 or 24 h after exposure using both methods. The percentage of AIF-positive nuclei in RF-field-exposed neurons was increased by three- to sevenfold compared to other conditions, while no increase in caspase 3 activity was found.
Odaci E, Bas O, Kaplan S · 2008
Researchers investigated the effects of prenatal EMF exposure on the number of granule cells in the dentate gyrus of 4-week-old rats. Pregnant rats in the exposed group were subjected to a 900 MHz EMF for 60 min/day between the first and last days of gestation. The results showed that prenatal EMF exposure caused a decrease in the number of granule cells in the dentate gyrus (P < 0.01).
Joubert V, Bourthoumieu S, Leveque P, Yardin C. · 2008
French researchers exposed rat brain cells to cell phone-level radiofrequency radiation (900 MHz at 2 W/kg SAR) for 24 hours and found it triggered programmed cell death through a specific cellular pathway. The brain cells died at rates significantly higher than control groups, even when accounting for the slight temperature increase from the radiation. This suggests that RF radiation can damage neurons through mechanisms beyond just heating effects.
Falzone N et al. · 2008
Researchers exposed ejaculated, density-purified human spermatozoa to pulsed 900 MHz GSM radiation at SAR levels of 2.0 and 5.7 W/kg and compared them with controls over time. Mitochondrial membrane potential was measured by flow cytometry and showed no effect from the radiation. Sperm motility was assessed by computer-assisted sperm analysis, and all kinematic parameters were unaffected at 2.0 W/kg. At 5.7 W/kg, straight-line velocity and beat-cross frequency were significantly impaired over time (P < 0.05), with no exposure-by-time interaction. The authors state the result should not be ascribed to thermal effects due to cooling methods and temperature control.
Valbonesi P et al. · 2008
Researchers used the human trophoblast cell line HTR-8/SVneo to evaluate HSP70 and HSC70 protein and gene expression and primary DNA damage after nonthermal exposure to pulse-modulated 1817 MHz GSM-217 Hz waves for one hour at a SAR of 2 W/kg. Heat shock significantly enhanced HSP70 expression but not HSC70 expression. Exposure to high-frequency EMFs did not change HSP70 or HSC70 protein or gene expression. Hydrogen peroxide caused a significant increase in DNA strand breaks, but EMF exposure did not. Overall, no evidence was found that the exposure induced a HSP70-mediated stress response or primary DNA damage.
Prisco MG et al. · 2008
Speit G, Schütz P, Hoffmann H. · 2007
German researchers attempted to replicate the controversial REFLEX study findings that showed cell phone radiation (1800 MHz) could damage DNA in human cells. Using identical equipment, cells, and exposure conditions, they found no DNA damage whatsoever. This directly contradicted the original REFLEX results that had suggested radiofrequency radiation at levels similar to cell phones could be genotoxic (DNA-damaging).
Speit G, Schütz P, Hoffmann H. · 2007
Researchers exposed ES1 cells to 1800 MHz RF-EMF at 2 W/kg SAR with intermittent exposure and tested for DNA damage using the alkaline comet assay and micronucleus test. They also tested V79 Chinese hamster cells and found no genotoxic effect in either assay. Quality control measures were used to rule out test performance issues, exposure failure, or evaluation bias.
Zhao R, Zhang S, Xu Z, Ju L, Lu D, Yao G. · 2007
Researchers exposed rat brain cells to cell phone radiation (1800 MHz) for 24 hours and found 34 genes changed their activity levels, affecting cell structure and function. This shows mobile phone radiation can alter how genes work in brain cells.
Zhao R, Zhang S, Xu Z, Ju L, Lu D, Yao G. · 2007
Researchers investigated whether 1800 MHz radiofrequency electromagnetic fields could influence gene expression in rat neurons. Among 1200 candidate genes, 24 were up-regulated and 10 were down-regulated after 24 hours of intermittent exposure at a SAR of 2 W/kg. The researchers concluded that gene expression in rat neurons could be altered by exposure to radiofrequency electromagnetic fields under their experimental conditions.
Sanchez et al. · 2007
The study investigated heat-shock protein expression and apoptosis in human primary keratinocytes and fibroblasts. The exposure used a GSM-1800 signal at 1800 MHz with 217 Hz modulation for 48 hours at an SAR of 2 W/kg. The GSM-1800 exposure produced no effect on either cell type, while UVB radiation and heat shock injured cells. The authors concluded that the GSM-1800 signal does not act as a stress factor on human primary skin cells in vitro.
Platano D et al. · 2007
Italian researchers exposed rat brain cells to 900 MHz radiofrequency radiation (the same frequency used by GSM cell phones) for short periods to see if it affected calcium channels, which are crucial for nerve cell communication. They found no changes in how calcium moved through these channels, even at radiation levels of 2 W/kg. This suggests that brief cell phone-level exposures may not immediately disrupt this particular aspect of brain cell function.
