Ha M, Im H, Lee M, Kim HJ, Kim BC, Gimm YM, Pack JK. · 2007
Researchers selected leukemia and brain cancer patients under age 15 and matched controls from 14 South Korean hospitals using the Medical Insurance Data System. Exposure to RFR from 31 AM transmitters of at least 20 kW was estimated using a GIS-based prediction program calibrated with measurements. The odds ratio for all leukemia was 2.15 for children within 2 km of the nearest transmitter versus those beyond 20 km. For total RFR exposure, lymphocytic leukemia odds ratios were 1.39 and 1.59 in the second and third quartiles versus the lowest, and brain cancer was not associated with AM RFR.
Erdreich LS et al. · 2007
The study's objective was to measure environmental, behavioral, and engineering factors affecting RF power output of GSM mobile phones during operation. They estimated RF-field exposure of volunteers using software-modified phones that recorded output power settings during a 5-day period. The largest factor affecting energy output was study area, followed by user movement and location, hands-free device use, and urbanicity, though the latter two accounted for trivial variance.
Clark ML et al. · 2007
Researchers measured estrogen and melatonin metabolites in overnight urine from women living near radio and television transmitters. Among premenopausal women, no associations were found between RF or 60-Hz exposure and either metabolite.
Barker AT et al. · 2007
Researchers conducted a double-blind study with 120 healthy volunteers who completed six exposure sessions with GSM and TETRA handset signals. They also measured blood catechols before and after exposure, heart rate variability during exposure, and 24-hour ambulatory blood pressure after exposure. The study had power to detect mean arterial pressure changes smaller than 1 mmHg, but no measurement showed any effect attributable to radiofrequency exposure. A single statistically significant decrease of 0.7 mmHg in mean arterial pressure occurred with GSM handsets in sham mode, which the authors suggest may be due to a slight increase in handset operating temperature.
Avdikos A et al. · 2007
The isolated leiomyosarcoma cells were cultured and exposed to a resonant low intensity radiofrequency EMF at frequencies between 10 kHz to 120 kHz for 45 minutes daily over two consecutive days. Three-month-old female Wistar rats were inoculated with leiomyosarcoma cells that had been exposed or not exposed to the EMF. Rats exposed to resonant EMF after tumor appearance (EG-I) showed tumor regression to 66% incidence and had longer survival and slower tumor growth than the other groups.
Alanko T, Hietanen M · 2007
Researchers assessed worker exposure to radiofrequency fields in two medium-sized antenna towers. The towers had transmitting antennas from mobile phone networks, radio, digital TV sub-stations, and amateur radio. Measurements were taken close to the tower ladders. All measured values were below ICNIRP occupational reference levels.
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.
Parazzini M et al. · 2007
Researchers exposed 26 healthy young volunteers to 900 MHz GSM phone radiation and sham exposure in separate double-blind sessions. A rest-to-stand protocol assessed autonomic nervous system function during rest and after sympathetic activation. No statistically significant effect of EMF exposure was found on the main RR mean or most other heart rate variability parameters. A weak interaction between some time and frequency domain HRV parameters and RF exposure was observed around the sympathetic response to standing.
Abdel-Rassoul G et al. · 2007
A cross-sectional study enrolled 85 residents living near a mobile phone base station in Egypt and 80 matched controls. Exposed residents reported significantly higher rates of headache, memory changes, dizziness, tremors, depressive symptoms, and sleep disturbance than controls. On neurobehavioral testing, exposed residents performed worse on a test of attention and short-term auditory memory but better on tests of visuomotor speed and attention. Residents living opposite the station performed worse on a problem-solving test than those living under the station. Measured radiofrequency radiation levels were below the allowable standard.
Tillmann T et al. · 2007
Researchers exposed 1170 B6C3F1 mice to GSM signals at 902 MHz and DCS signals at 1747 MHz for 2 h per day, 5 days per week over 2 years at SAR levels of 0.4, 1.3, and 4.0 mW/g. Pairwise Fisher's test showed no significant increase in any tumor type in RF-exposed groups compared to sham-exposed groups. Observed tumor rates were within the range of historical control data for untreated mice.
Dimbylow P. · 2007
Researchers used finite-difference time-domain calculations to estimate SAR from 20 MHz to 3 GHz in hybrid voxel-mathematical models of the pregnant female. Mathematical models of the developing foetus at 8-, 13-, 26- and 38-week gestation were converted into voxels and combined with the reference adult female model, NAOMI at a resolution of 2 mm. The study calculated the electric field values needed to produce the ICNIRP public exposure restriction of 2 W kg(-1) when averaged over 10 g of the foetus.
Crouzier D et al. · 2007
Researchers exposed freely moving rats for 24 hours to a 1.8 GHz GSM radiofrequency signal at low power density. The study tracked acetylcholine release in the hippocampus, EEG, EMG, and subcutaneous temperature, and also analyzed brain lipid extracts using NMR after the animals were sacrificed. No significant changes in any measured parameter were observed under radiofrequency exposure, and the NMR study also failed to show any effect.
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.
Regel SJ et al. · 2007
Researchers exposed the heads of 15 healthy male subjects for 30 min prior to sleep to a pulse-modulated EMF signal at different intensities or a sham condition, in a double-blind, crossover design. The active exposure levels used peak spatial specific absorption rates of 0.2 W kg–1 and 5 W kg–1. Sleep EEG analysis showed a dose-dependent increase of power in the spindle frequency range in non-REM sleep, while sleep architecture was not affected. Reaction speed slowed with increasing field intensity in the 1-back task, but accuracy in the CRT and N-back tasks was not affected in a dose-dependent manner.
Kumlin T et al. · 2007
Researchers exposed young male Wistar rats to a 900 MHz mobile phone signal for 2 h/day on 5 days/week. After 5 weeks of exposure at whole-body average specific energy absorption rates of 0.3 or 3.0 W/kg or sham exposure, rats were assessed for behavioral and morphological changes. No degenerative changes, dying neurons, or effects on blood-brain barrier leakage were detected, and no group differences appeared in the open-field, plus maze, or acoustic startle response tests. In the water maze test, significantly improved learning and memory were detected in rats exposed to RF fields.
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.
Unknown authors · 2006
Researchers exposed two human cell lines, neuronal SK-N-SH and monocytoid U937, to a 900 MHz RF signal pulsed at 217 Hz with a SAR of 0.2 W/kg. For SK-N-SH cells, they assessed effects using gene microarray, real-time PCR, Western blot for heat shock proteins, and flow cytometry for cell cycle and apoptosis. For U937 cells, they assessed effects using cell viability and cell cycle analysis. No significant difference was found between sham-exposed and radiofrequency-exposed cells in any assay or condition.
Unknown authors · 2006
PMA treatment significantly increased ROS production in both cell types compared to sham or incubator controls. GSM-DTX exposure showed significantly different ROS production in monocytes compared to sham, but this was due to lowered ROS release during sham exposure. No ROS differences were detected in lymphocytes compared to sham or incubator control. Hsp70 expression in monocytes at 0, 1, and 2 hours post-exposure to GSM-DTX at 2 W/kg for 1 hour did not differ from incubator or sham controls.
Hondou T et al et al. · 2006
Researchers conducted a numerical investigation using a realistic human body model and an actual elevator size to assess SAR from a mobile phone modeled as a dipole antenna at 16 mm from the head. They used finite-difference time-domain technique with a supercomputer at frequencies of 900, 1500, and 2000 MHz with 250 mW transmitting power. Results showed that peak 10-g SAR depends on passenger and antenna position, with substantial increases in whole-body average SAR and peak 10-g SAR in the elevator over free-space values. However, the maximum values met international RF safety guidelines, with whole-body average SAR at 4.4% and peak spatial-average SAR at 78% of the guideline.
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.
