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.
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.
Remondini D et al. · 2006
Researchers exposed six human cell types to 900 and 1800 MHz microwaves and analyzed gene expression using whole-genome cDNA arrays. NB69 neuroblastoma cells, T lymphocytes, and CHME5 microglial cells did not show significant changes in gene expression. EA.hy926 endothelial cells, U937 lymphoblastoma cells, and HL-60 leukemia cells showed between 12 and 34 up- or down-regulated genes. The affected gene families did not indicate a stress response.
Qutob SS et al. · 2006
Researchers exposed U87MG glioblastoma cells to a 1.9 GHz pulse-modulated RF field for 4 hours at SARs of 0.1, 1.0, and 10.0 W/kg to assess global gene expression. No evidence was found that non-thermal RF fields affect gene expression in these cells compared to nonirradiated controls. Heat shock at 43°C for 1 hour up-regulated typical stress-responsive genes in the positive control group.
Natarajan M et al. · 2006
Human Mono Mac 6 cells were exposed intermittently to pulsed EMF for 90 minutes with a pulse width of 0.79 ns and a repetition rate of 250 pps at 1 kV/cm. Cells exposed to the EMF showed a 3.5-fold increase in NFKB DNA-binding activity at 24 hours postexposure. No difference was found in NFKB-dependent gene expression profiles at 8 or 24 hours postexposure. Pulsed EMF exposure did not induce NFKB-driven luciferase activity, indicating the activation was functionally inactive.
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.
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.
Verschaeve L et al. · 2006
Researchers investigated combined genotoxic effects of 900 MHz radiofrequency fields and the drinking water mutagen MX in female rats over two years. MX induced DNA damage in rat brain but not in blood or liver cells. Co-exposure to RF fields and MX did not significantly increase DNA damage in blood, liver, or brain compared to MX alone. The study used alkaline comet assay and micronucleus tests on samples taken at multiple time points.
Stronati L et al. · 2006
The study used alkaline comet assay, metaphase analysis, micronucleus test, and nuclear division index to assess DNA strand breaks, chromosomal aberrations, sister chromatid exchanges, micronuclei, and cell cycling speed. It comprehensively examined whether 24-hour continuous exposure to a 935 MHz GSM signal at 1 or 2 W/kg is genotoxic per se or can influence x-ray genotoxicity. Within the experimental parameters, no effect from the RFR signal was observed in any instance. The SAR values chosen were near the upper limit of energy absorption in localized tissue during cellular telephone use.
Sakuma N et al. · 2006
Researchers conducted a large-scale in vitro study to test whether modulated RF fields from mobile radio base stations act as a DNA damaging agent. Human glioblastoma A172 cells and normal human IMR-90 fibroblasts were exposed to 2.1425 GHz CW and W-CDMA radiation. A172 cells were exposed to W-CDMA at SARs of 80, 250, and 800 mW/kg and CW at 80 mW/kg for 2 and 24 hours, while IMR-90 cells were exposed to both modulations at 80 mW/kg for the same periods. No significant differences in DNA strand breaks were observed between exposed groups and sham controls using alkaline comet assays. The authors concluded that low-level exposures do not act as a genotoxicant up to a SAR of 800 mW/kg.
Maes A, Van Gorp U, Verschaeve L. · 2006
Researchers investigated cytogenetic effects in peripheral blood lymphocytes from subjects professionally exposed to mobile phone electromagnetic fields. The alkaline comet assay, sister chromatid exchange and chromosome aberration tests revealed no evidence of RFR-induced genetic effects. Blood cells were also exposed to mitomycin C to investigate possible combined effects of RFR and the chemical mutagen. No cooperative action was found between the electromagnetic field exposure and the mutagen using either the comet assay or SCE test.
Vian A et al. · 2006
The study aimed to investigate how microwave irradiation affects gene expression in plants. Researchers used a carefully calibrated system that mimics environmental electromagnetic fields to measure changes in mRNA encoding a stress-related bZIP transcription factor. Exposure to low-amplitude, short-duration 900 MHz EMF evoked a rapid 3.5-fold accumulation of this mRNA, peaking 5–15 minutes after stimulation, similar to mechanical stimulation.
Ferreira AR et al. · 2006
Researchers used the micronucleus assay to assess chromosomal damage in erythrocytes from rat offspring exposed to non-thermal UHF-EMF from a cellular phone during embryogenesis. The irradiated group showed a significant increase in micronuclei occurrence. No significant differences were found in any oxidative parameter of offspring blood and liver. The average number of pups in each litter was not significantly altered.
Dawe AS et al. · 2006
The study compared heat-shock gene expression in nematodes exposed to 1.0 GHz microwaves at 0.5 W in copper and silver-plated TEM cells. In copper cells, exposed samples were up to 0.2°C warmer than sham controls, and a 20% increase in reporter expression was observed. The authors concluded that the original non-thermal interpretation cannot be sustained and at least part of the effect is thermal.
Zhao R, Zhang SZ, Yao GD, Lu DQ, Jiang H, Xu ZP · 2006
Zeng Q, Chen G, Weng Y, Wang L, Chiang H, Lu D, Xu Z. · 2006
Researchers investigated gene and protein responses to GSM 1800 MHz RF EMF in human breast cancer MCF-7 cells using genomic and proteomic approaches. GeneChip analysis identified a handful of changed genes after exposure at SAR up to 3.5 W/kg for 24 hours, but these changes were not confirmed by RT-PCR. Proteome analysis found a few different proteins differentially expressed under continuous or intermittent exposure at SAR 3.5 W/kg for 24 hours or less, but the authors suggest these effects might have occurred by chance.
Zeng QL, Weng Y, Chen GD, Lu DQ, Chiang H, Xu ZP · 2006
Researchers exposed MCF-7 human breast cancer cells to GSM 1800 MHz RF EMF at 3.5 W/kg SAR for various durations and modes. They used 2-dimensional electrophoresis and PDQuest software to analyze protein expression. No differential proteins were found after 6 hours of continuous exposure. Eighteen differential proteins were detected after 3-hour intermittent exposure and seven after 12-hour continuous exposure. The analysis suggested that the differentially expressed proteins should be related to biosynthesization, signal transduction, and DNA damage and repair.
Trosic I, Busljeta I. · 2006
Researchers exposed rats to 2.45 GHz microwave radiation at a whole-body SAR of 1.25+/-0.36 W/kg for 2 hours per day, 7 days a week. Bone marrow polychromatic erythrocytes increased on days 8 and 15, and peripheral blood polychromatic erythrocytes increased on days 2 and 8. Bone marrow micronucleated PCE frequency increased on day 15, and peripheral blood micronucleated PCEs increased on day 8, but all values declined nearly to control levels by the end of the experiment.
Pavicic I, Trosic I, Sarolic A · 2006
Researchers compared the effects of 864 MHz and 935 MHz microwave radiation on V79 cell proliferation, colony formation, and viability. Cells exposed to 864 MHz for 2 or 3 hours showed significantly reduced growth on day 3, whereas 3-hour 935 MHz exposure significantly increased growth. Colony-forming ability and viability did not differ significantly from controls for either frequency.
Sun LX, Yao K, Jiang H, He JL, Lu DQ, Wang KJ, Li HW · 2006
Researchers exposed cultured human lens epithelial cells to 217 Hz modulated microwave radiation at four SAR levels for 2 hours. DNA single strand breaks were measured using the comet assay immediately after irradiation and at 30 and 60 minutes afterward. At the highest dose, significant DNA damage remained one hour after irradiation and cell proliferation was significantly decreased.
Nylund R, Leszczynski D. · 2006
Researchers examined in vitro cell response to mobile phone radiation using two variants of a human endothelial cell line: EA.hy926 and EA.hy926v1. Gene expression changes were examined using cDNA Expression Arrays and protein expression changes were examined using 2-DE and PDQuest software. Gene and protein expression were altered in both examined cell lines after one hour of exposure at an average specific absorption rate of 2.8 W/kg, but the same genes and proteins were differently affected in each line.
