Manti L et al. · 2008
Researchers exposed human peripheral blood lymphocytes in vitro to a UMTS signal at a frequency carrier of 1.95 GHz for 24 hours at 0.5 and 2.0 W/kg SAR. Cells were also given 4 Gy of X rays immediately before RF radiation or sham exposures, and chromosome aberrations were measured by fluorescence in situ hybridization. No significant variations due to the UMTS exposure were found in the fraction of aberrant cells, but the frequency of exchanges per cell showed a small but statistically significant increase of 0.11 exchange per cell compared to 0 W/kg SAR.
Ribeiro EP, Rhoden EL, Horn MM, Rhoden C, Lima LP, Toniolo L · 2007
Researchers randomly divided 16 male Wistar rats into experimental and control groups; the experimental group was exposed to GSM radiofrequency (1,835–1,850 MHz) for 1 hour daily over 11 weeks. They measured rectal temperature, testicular and epididymal weight, lipid peroxidation, serum testosterone, sperm count, and histopathological endpoints. No statistically significant differences were found between exposed and control groups in any measured endpoint.
Chauhan V et al. · 2007
Researchers exposed human-derived cell lines TK6, HL60, and Mono-Mac-6 to intermittent 1.9 GHz pulse-modulated RF fields for 6 hours at SARs of 0, 1, and 10 W/kg. Cell viability, apoptosis, and cell cycle kinetics were measured immediately after exposure and 18 hours later. Cytokine expression (TNFA, IL1B, IL6, IL8, IL10, IL12) was also assessed. No detectable changes in cell viability, cell cycle kinetics, apoptosis, or cytokine expression were observed in any exposed group compared to sham controls. The positive heat-shock control showed decreased viability, increased apoptosis, and a G(2)/M cell cycle block.
Chauhan V et al. · 2007
Researchers examined the effect of RF field exposure on late onset gene expression in U87MG cells after a 24 h exposure period. A human monocyte-derived cell line (MM6) was exposed to intermittent RF fields for 6 h and gene expression was assessed immediately and at 18 h postexposure. Both cell lines were exposed to 1.9 GHz pulse-modulated RF fields for 6 or 24 h at SARs of 0.1-10.0 W/kg. The study found no evidence that nonthermal RF field exposure altered gene expression in either U87MG or MM6 cells relative to nonirradiated controls. Heat shock at 43°C for 1 h altered the expression of well-characterized heat-shock proteins in both cell lines.
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.
Platano D et al. · 2007
Researchers studied the non-thermal effects of radiofrequency electromagnetic fields on barium currents through voltage-gated calcium channels in primary cultures of rat cortical neurons using the patch-clamp technique. Neurons were exposed for one to three periods of 90 seconds to 900 MHz continuous wave or GSM-modulated signals during whole-cell recording at specific absorption rates of 2 W/kg for both modulation types. Single or multiple acute exposures to either continuous wave or GSM-modulated 900 MHz fields did not significantly alter the current amplitude or the current-voltage relationship through voltage-gated calcium channels.
Hirose H et al. · 2007
Researchers performed an in vitro study of low-level RF fields from IMT-2000 base stations to test if modulated signals cause hsp27 phosphorylation and overexpression. No significant differences in phosphorylated hsp27 at serine 82 or in hsp gene expression were found between exposed and sham-exposed groups.
Guney M, Ozguner F, Oral B, Karahan N, Mungan T. · 2007
Rats were randomly assigned to four groups of eight each, including a control, a sham, a 900 MHz EMR exposure group, and an EMR plus vitamins E and C group, and the EMR groups received 30 minutes per day for 30 days. EMR exposure increased endometrial nitric oxide and malondialdehyde levels and decreased superoxide dismutase, catalase, and glutathione peroxidase activities, while combined vitamins E and C reversed these changes. The EMR group showed diffuse severe apoptosis in endometrial epithelial, glandular, and stromal cells and diffuse eosinophilic leucocyte and lymphocyte infiltration, which were significantly reduced by vitamins E and C.
Barcal J, Vozeh F · 2007
ECoG evaluation showed a distinct shift to lower frequency components in wild type mice but only gentle differences in Lurcher mutant mice. Hippocampal rhythmicity showed gentle changes with increase of higher frequencies and changes in theta oscillations in both healthy and mutant mice.
Zeni et al. · 2007
Researchers investigated whether 900 MHz RF radiation could induce reactive oxygen species in murine L929 fibrosarcoma cells, with or without co-exposure to MX, a potent environmental carcinogen produced during chlorination of drinking water. Both continuous-wave and GSM mobile phone signals were applied for 10 or 30 min at specific absorption rates of 0.3 and 1 W/kg. The study found no indication that RF-field exposure, alone or combined with MX, induced reactive oxygen species formation, while MX alone caused a statistically significant increase in reactive oxygen species for all the treatment durations investigated.
Tkalec M, Malarić K, Pevalek-Kozlina B. · 2007
Researchers exposed duckweed (Lemna minor) to radiofrequency electromagnetic fields at 400 and 900 MHz, at field strengths of 10, 23, 41, and 120 V m−1, for 2 hours, and also tested a longer 4-hour exposure and modulated fields. After exposure, the researchers measured lipid peroxidation, H2O2 content, antioxidative enzyme activities and isoenzyme patterns, and HSP70 expression. At 900 MHz, almost all exposure treatments significantly increased lipid peroxidation and H2O2 content, mostly decreased PPX activity, and did not affect CAT activity. No differences in isoenzyme patterns of antioxidative enzymes or HSP70 level were found between control and exposed plants at either frequency.
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.
Buttiglione M et al. · 2007
Researchers exposed human neuroblastoma SH-SY5Y cells to 900 MHz radiofrequency radiation at 1 W/kg to study effects on gene expression and cell-cycle control. Short-term exposures produced a transient increase in Egr-1 mRNA levels along with activation of the MAPK subtypes ERK1/2 and SAPK/JNK. Exposure had an anti-proliferative effect, and a significant G2-M cell-cycle arrest was observed, with signs of apoptosis appearing after 24 hours. A significant decrease in mRNA levels of Bcl-2 and survivin genes, both linked to signaling between G2-M arrest and apoptosis, was also observed.
Whitehead TD, Moros EG, Brownstein BH, Roti Roti JL. · 2006
Researchers exposed cultured C3H 10T 1/2 cells to cell phone RF radiation at a specific absorption rate of 5 W/kg for 24 hours. Gene expression was measured using Affymetrix microarrays and compared to sham controls. The RF exposure did not produce more gene expression changes than expected by chance. In contrast, X-ray exposure at 0.68 Gy with a 4-hour recovery produced more changes than the sham comparison.
Whitehead TD, Moros EG, Brownstein BH, Roti Roti JL · 2006
Researchers performed in vitro experiments with C3H 10T(1/2) mouse cells to test whether FDMA or CDMA modulated RF radiation induces changes in gene expression. Cells were exposed to either modulation for 24 h at a specific absorption rate (SAR) of 5 W/ kg. Gene expression was evaluated using the Affymetrix U74Av2 GeneChip to detect changes in mRNA levels. As a positive control, cells were exposed to 0.68 Gy of X rays and gene expression was evaluated 4 h after exposure. For both CDMA and FDMA radiation, the number of probe sets with expression changes greater than 1.3-fold was less than or equal to the expected false positives, indicating no statistically significant effect on gene expression.
Wang LL, Chen GD, Lu DQ, Chiang H, Xu ZP. · 2006
Researchers intermittently exposed MCF-7 cells to GSM 1800 MHz RF EMF modulated by 217 Hz for 24 hours at SARs of 2.0 W/kg or 3.5 W/kg. A small number of differentially expressed genes were found after exposure. Reproducible analysis yielded no genes at 2.0 W/kg and five up-regulated genes at 3.5 W/kg. The five genes identified at 3.5 W/kg could not be confirmed by RT-PCR. The authors concluded that the study did not provide clear evidence of distinct gene expression changes under the experimental conditions.
Vijayalaxmi · 2006
Researchers exposed peripheral blood lymphocytes from healthy volunteers to 2.45 GHz or 8.2 GHz pulsed-wave RF radiation for 2 hours. They measured chromosomal aberrations and micronuclei to assess cytogenetic damage. The RF-exposed lymphocytes showed no significant increase in damage compared to sham-exposed lymphocytes. Gamma-irradiated positive control cells showed significantly more damage than both RF-exposed and sham-exposed cells.
Tuschl H, Novak W, Molla-Djafari H. · 2006
The study assessed whether GSM-modulated RF fields have adverse effects on the functional competence of human immune cells. Exposure was performed at GSM Basic 1950 MHz with an SAR of 1 mW/g in an intermittent mode of 5 minutes on and 10 minutes off for 8 hours. Researchers evaluated intracellular cytokine production, immune-relevant gene activity, and cytotoxicity of lymphokine-activated killer cells using blood from at least 15 donors per parameter. No statistically significant effects of exposure were found.
Sukhotina I, Streckert JR, Bitz AK, Hansen VW, Lerchl A · 2006
Researchers exposed isolated pineal glands from Djungarian hamsters to 1800 MHz continuous wave or GSM-modulated signals at SAR levels of 8, 80, 800, and 2700 mW/kg for 7 hours. At 800 mW/kg SAR both signal types significantly enhanced melatonin release, but at 2700 mW/kg SAR continuous wave elevated melatonin while GSM-modulated exposure suppressed it. The authors concluded that the data do not support the melatonin hypothesis that nonthermal radiofrequency exposure suppresses melatonin synthesis.
Scarfi MR et al. · 2006
Researchers exposed human peripheral blood lymphocytes from 10 healthy donors to 900 MHz GSM signals at SARs of 0, 1, 5, and 10 W/kg for 24 hours. The cytokinesis-block micronucleus assay showed no genotoxic or cytotoxic effects across the range of SARs investigated. Two independent laboratories (ENEA Rome and CNR-IREA Naples) each tested five donors and cross-scored slides, confirming the findings.
Merola P et al. · 2006
The study examined whether a modulated 900 MHz radiofrequency field at a specific absorption rate higher than the ICNIRP occupational reference level could alter cell proliferation, differentiation, and apoptosis in a neuroblastoma cell line. Cells were exposed for 24, 48, and 72 hours and tested using WST-I assay, molecular markers, caspase activation, and PARP cleavage detection. Combined exposures with retinoic acid and camptothecin were also tested to check for interference between the field and chemical agents. Overall, the data suggest that 900 MHz radiofrequency exposure up to 72 hours does not induce significant alterations in the three principal cell activities.
Lee JS, Huang TQ, Kim TH, Kim JY, Kim HJ, Pack JK, Seo JS. · 2006
Researchers exposed human T-lymphocyte Jurkat cells and rat primary astrocytes to 1763 MHz RF radiation at SARs of 2 or 20 W/kg for 30 minutes or 1 hour while temperature was completely controlled at 37 +/- 0.2 degrees C. No detectable difference was observed in the expression levels of HSP90, HSP70, and HSP27, and the phosphorylation status of MAPKs did not change significantly. When TPA alone was applied, MAPKs were phosphorylated in a dose-dependent manner, but RF radiation did not enhance TPA-induced MAPK phosphorylation, and neither TPA nor RF radiation affected HSP induction.
Lantow M, Viergutz T, Weiss DG, Simko M. · 2006
Researchers used human Mono Mac 6 cells and exposed them to a 1,800 MHz GSM-DTX signal at 2 W/kg SAR for 12 hours. They measured cell cycle kinetics, BrdU uptake, apoptosis, and necrosis using flow cytometry. No statistically significant differences were found in apoptosis, necrosis, cell cycle kinetics, or BrdU uptake between RF EMF-exposed cells and sham or incubator controls. Positive controls treated with gliotoxin and PMA showed significant increases in apoptosis and necrosis, and PMA caused a significant accumulation of cells in G0/G1 phase with a reduction in S-phase cells.
Hirose H et al. · 2006
Researchers conducted a large-scale in vitro study to test whether modulated RF fields from mobile radio base stations induce apoptosis or stress responses activating p53. Human glioblastoma A172 cells were exposed to W-CDMA radiation at SARs of 80, 250, and 800 mW/kg and CW radiation at 80 mW/kg for 24 or 48 hours, while human IMR-90 fibroblasts were exposed to both modulations at 80 mW/kg for 28 hours. No significant differences in apoptosis, phosphorylated p53 at serine 15, total p53, or downstream gene expression were found between exposed and sham-exposed cells.
Chauhan V et al. · 2006
Researchers exposed HL-60 and MM6 cells to intermittent 1.9 GHz pulse-modulated RF fields at SARs of 1 and 10 W/kg for 6 hours. No significant changes in gene expression were found between sham-exposed and RF-exposed groups in either cell line. Positive heat-shock controls showed significant increases in HSP27, HSP70, c-fos, and c-jun at both time points.
