Bachmann M et al. · 2007
Researchers studied how the human brain's bioelectrical activity adapted to low-level microwave exposure in a group of 14 healthy volunteers. The volunteers were exposed to 450 MHz microwave radiation modulated at 40 Hz frequencies, with a field power density at the scalp of 0.16 mW/cm(2). Results showed that an initial increase in EEG power was compensated and even overcompensated, with adaptation effects apparent in alpha and beta rhythms.
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.
Ning W, Xu SJ, Chiang H, Xu ZP, Zhou SY, Yang W, Luo JH · 2007
Researchers cultured hippocampal neurons from rats and exposed them to GSM 1800 MHz microwaves at either 2.4 or 0.8 W/kg for 15 minutes each day from DIV6 to DIV14. At 2.4 W/kg, the density and mobility of dendritic filopodia at DIV8 and the density of mature spines at DIV14 were significantly decreased, and the average length of dendrites per neuron at DIV10 and DIV14 was also decreased. Dendritic arborization was unaltered in the exposed neurons, and no significant changes were found in neurons exposed to 0.8 W/kg.
Meral I et al. · 2007
In brain tissue, the MDA level increased and GSH level and CAT enzyme activity decreased in EMF-exposed guinea pigs, while vitamins A, E, and D3 levels did not change. In blood, MDA, vitamins A, D3, and E levels, and CAT enzyme activity increased, while GSH level decreased in the EMF-exposed guinea pigs.
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.
Hung CS, Anderson C, Horne JA, McEvoy P · 2007
Researchers exposed 10 healthy young adults to talk, listen, standby, or sham signal modes for 30 minutes, then gave them a 90-minute sleep opportunity. Sleep latency after talk mode was markedly and significantly delayed beyond listen and sham modes. This condition effect was also evident in 1–4 Hz EEG frontal power, a frequency range described as particularly sensitive to sleep onset. There was no condition effect for subjective sleepiness.
Brillaud E, Piotrowski A, de Seze R · 2007
Researchers measured GFAP expression in rat brains 2, 3, 6, and 10 days after a single 15-minute 900 MHz GSM exposure at a brain averaged SAR of 6 W/kg. A statistically significant increase in GFAP stained surface area was observed 2 days after exposure in the frontal cortex and the caudate putamen. A smaller statistically significant increase was noted 3 days after exposure in those same areas and in the cerebellum cortex. The researchers concluded this was a temporary effect, probably due to a hypertrophy of glial cells, and noted that whether the effect could be harmful remains to be studied.
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.
Yuasa K et al. · 2006
Researchers studied somatosensory evoked potentials in 12 normal volunteers before and after 30 minutes of mobile phone exposure compared with sham exposure. In 7 of the 12 volunteers, the recovery function of the somatosensory evoked potential was also measured. Neither the somatosensory evoked potentials nor their recovery function were affected by the mobile phone exposure or sham exposure.
Thorlin et al. · 2006
Researchers exposed cultured astroglial and microglial cells to 900 MHz microwave radiation at various SARs and durations. They measured markers including interleukin 6, tumor necrosis factor-alpha, glial fibrillary acidic protein, total protein, and ED-1. No significant differences were found for any parameter at any time or radiation characteristic. Total protein levels remained constant and cell morphology appeared unaffected. The study concluded no evidence for effects on damage-related factors in glial cells.
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.
Schüz J et al. · 2006
Researchers followed a nationwide cohort of 420,095 Danish cellular telephone subscribers from 1982 to 1995 through 2002 for cancer incidence. A total of 14,249 cancers were observed with a standardized incidence ratio of 0.95 (95% CI 0.93 to 0.97) for men and women combined. Cellular telephone use was not associated with increased risk for brain tumors, acoustic neuromas, salivary gland tumors, eye tumors, or leukemias. Among long-term subscribers of 10 years or more, there was no increased risk for brain tumors and no trend with time since first subscription. Smoking-related cancer risk was decreased among men but increased among women.
Schuz J et al. · 2006
Researchers conducted a population-based case-control study in Germany with 747 brain tumor cases and 1494 matched controls aged 30 to 69 years. Exposure was assessed by the location of a DECT cordless phone base station close to the bed as a proxy for continuous low-level radiofrequency electromagnetic field exposure during the night. Estimated odds ratios were 0.82 (95% CI 0.29-2.33) for glioma and 0.83 (0.29-2.36) for meningioma, with no increasing risk observed with longer exposure duration.
Schuz J et al. · 2006
Researchers conducted a population-based case-control study in three German regions, enrolling 366 glioma cases, 381 meningioma cases, and 1,494 controls. Overall cellular phone use was not associated with brain tumor risk, with odds ratios of 0.98 for glioma and 0.84 for meningioma. Among long-term users of 10 or more years, glioma risk was elevated (odds ratio 2.20) but meningioma risk was not, and cordless phone use showed no association with either tumor.
Russo R et al. · 2006
The study tested 168 volunteers on three cognitive tasks: a simple reaction task, a vigilance task, and a subtraction task. Participants completed the tasks in two sessions, one with RF exposure (GSM or CW signals) and one with sham exposure. No significant effects of RF exposure on performance were found for either GSM or CW signals, regardless of phone position.
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.
Muscat JE, Hinsvark M, Malkin M · 2006
Researchers analyzed time trends in age-adjusted incidence rates of adult neuronal cancers using SEER data from 1973 to 2002. The rates did not change during this period despite an exponential increase in mobile phone subscriptions starting in 1984. The results indicate that mobile phone use is unrelated to the risk of neuronal cancers.
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.
Maby E, Jeannes Rle B, Faucon G · 2006
Researchers studied auditory evoked potentials in nine healthy subjects and six epileptic patients to determine localized effects of GSM microwaves. They used a support vector machine-based parameter selection method to estimate parameters most altered by radiofrequencies and computed the topography of modifications. Epileptic patients showed a lengthening of the N100 component in the frontal area contralateral to the radiation, while healthy subjects showed an amplitude increase of the P200 wave in the frontal area. The study suggests that radiofrequency fields emitted by mobile phones modify the AEP but found no direct link to RF-induced brain function damage.
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.
Joubert V et al. · 2006
Researchers exposed human neuroblastoma SH-SY5Y cells to GSM-900 at 0.25 W/kg average SAR or continuous-wave 900 MHz at 2 W/kg SAR for 24 hours. No statistically significant difference in apoptosis rate was found between sham-exposed and microwave-exposed cells at either 0 or 24 hours post-exposure. Apoptosis rates were also comparable between sham, continuous-wave, 37°C, and 39°C exposed cells. Three assessment methods including DAPI staining, TUNEL/PI flow cytometry, and caspase-3 fluorimetry gave concordant results.
Hamblin DL, Croft RJ, Wood AW, Stough C, Spong J. · 2006
Researchers tested 120 participants in a double-blind, counterbalanced, crossover design with two sessions one week apart. In both sessions, participants performed auditory and visual oddball tasks while EEG was recorded with a mobile phone set to sham exposure mounted over the temporal region, and then performed the same tasks while the handset was set to active or sham. No significant differences were found between exposure conditions for any ERP component or reaction time.
Finnie JW, Cai Z, Blumbergs PC, Manavis J, Kuchel TR. · 2006
Researchers exposed pregnant mice to 900 MHz fields at 4 W/kg for 60 minutes daily from gestation day 1 to 19. Control mice were sham-exposed or freely mobile without restraint. Fetal brains were examined for c-fos expression in multiple regions using immunohistochemistry. No difference in c-fos immunoreactivity was found between exposed and control fetal brains.
Finnie JW, Blumbergs PC, Cai Z, Manavis J, Kuchel TR. · 2006
Pregnant mice were exposed to 900 MHz radiofrequency fields at 4 W/kg for 60 minutes daily from gestational day 1 to day 19. Fetal brains were examined for albumin extravasation in multiple regions including cerebral cortex, thalamus, basal ganglia, hippocampus, cerebellum, midbrain and medulla. No albumin extravasation was found in exposed or control brains, indicating no increase in vascular permeability.
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.
