Grafström G et al. · 2008
Swedish researchers exposed rats to GSM-900 cell phone radiation once weekly for over a year at power levels similar to what humans experience during phone calls. When they examined the rats' brains afterward, they found no signs of damage including blood-brain barrier leakage, cell death, or aging-related changes. This suggests that intermittent cell phone radiation exposure at typical usage levels may not cause detectable brain tissue damage.
Dimbylow PJ, Hirata A, Nagaoka T. · 2008
The study intercompared the HPA male and female models NORMAN and NAOMI with the NICT male and female models TARO and HANAKO. Particular emphasis was placed on how dielectric properties are assigned to tissues such as skin and fat and on the consequences of different SAR calculation algorithms at higher frequencies. Whole-body SAR calculations were performed at three institutions for a vertically polarized plane wave incident on the front of the body from 30 MHz to 3 GHz under isolated conditions.
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.
Zeni O et al. · 2008
Kleinlogel H et al. · 2008
Researchers tested 1950 MHz UMTS at SAR 0.1 and 1 W/kg and pulsed 900 MHz GSM at 1 W/kg on well-being and vigilance-controlled resting EEG in 15 healthy right-handed subjects. The study used a double-blind randomised crossover design. Neither UMTS nor GSM exposure produced significant changes in measured parameters compared to sham exposure. The results did not give evidence for a deleterious effect of the EMF on normal healthy mobile phone users.
Kleinlogel H et al. · 2008
Researchers exposed 15 healthy adults to electromagnetic fields from both GSM (2G) and UMTS (3G) mobile phones while measuring their brain activity with EEG and asking about their well-being. They found no significant changes in brain wave patterns or reported symptoms compared to fake (sham) exposure. The study suggests that typical mobile phone radiation levels don't produce detectable immediate effects on brain activity in healthy users.
Riddervold IS et al. · 2008
Forty adolescents and 40 adults were exposed to UMTS base station signals and sham conditions in a randomized, double-blinded cross-over design. Each exposure lasted 45 minutes while participants performed cognitive tasks and reported symptoms. No statistically significant differences were found between UMTS and sham conditions for the main cognitive test. An increase in headache rating was observed when combining both age groups, though this may reflect baseline differences.
Riddervold IS et al. · 2008
Danish researchers tested whether 45-minute exposures to UMTS cell tower radiation (2140 MHz) affected cognitive performance and symptoms in 40 teenagers and 40 adults. They found no significant differences in cognitive test performance between real and sham exposures, though participants reported slightly more headaches during radiation exposure, which may have been due to baseline differences rather than the radiation itself.
Unknown authors · 2008
Researchers tested 54 women (11 with self-reported mobile phone sensitivity and 43 controls) in a controlled lab setting using 2.14 GHz W-CDMA base station signals at 10 V/m for 30 minutes. Neither group could detect when EMF was actually present, and both groups showed identical psychological, cognitive, and autonomic responses to real versus fake exposure. The study found no evidence that people claiming EMF sensitivity actually respond differently to electromagnetic fields from cell towers.
Lerchl A et al. · 2008
Researchers exposed adult male Djungarian hamsters to RF-EMF at 383, 900, and 1800 MHz for 60 days at 80 mW/kg. Pineal and serum melatonin levels and organ weights were not affected in any experiment. Body weight increased transiently up to 4% at 383 MHz, increased up to 6% non-transiently at 900 MHz, and was unchanged at 1800 MHz.
Rao VS et al. · 2008
The study used neuronal cells differentiated from a mouse embryonic stem cell line and a frequency-tunable applicator to examine calcium dynamics in real time. Control cells showed about five spontaneous calcium spikes per cell in 60 minutes, while exposure to 800 MHz RF radiation at 0.5 W/kg increased spikes to 15.7 per cell. The increase depended on frequency but not on SAR between 0.5 and 5 W/kg, and involved N-type calcium channels and phospholipase C enzymes. Microfilament disruption prevented the calcium spikes.
Mazor R et al. · 2008
Researchers exposed human blood cells to 800 MHz radiofrequency radiation (similar to cell phone frequencies) for 72 hours at power levels close to current safety limits. They found significant increases in chromosome damage called aneuploidy, where cells gained or lost whole chromosomes. Importantly, this damage occurred even when temperature was carefully controlled, suggesting the radiation itself caused genetic harm through non-thermal mechanisms.
Devrim E et al. · 2008
EMR exposure increased MDA, XO, and GSH-Px activities in erythrocytes compared with controls. In kidney tissue, EMR increased MDA and CAT activities but decreased XO and ADA activities. In heart tissue, EMR decreased MDA, ADA, and XO activities. Vitamin C seems to make partial protection against oxidative stress in erythrocytes.
Kim JY et al. · 2008
The study investigated clastogenicity of 835-MHz RF-EMF using alkaline comet assay and chromosomal aberration test on mammalian cells. No direct cytogenetic effect was found in the chromosomal aberration test with RF-EMF alone. The comet assay showed nearly negative results for RF-EMF alone, with a small increase in tail moment. RF-EMF showed a potentiation effect in the comet assay when combined with model clastogens.
Stovner LJ, Oftedal G, Straume A, Johnsson A. · 2008
The study aimed to investigate headache type and location in a provocation study to gain insight into possible causes and mechanisms. Seventeen participants completed 130 trials of sham or RF exposure. No significant difference existed in headache type, laterality, or location between the two exposure types. In most participants, the headache was compatible with tension-type headache.
Lee KS, Choi JS, Hong SY, Son TH, Yu K. · 2008
Researchers studied biological effects of mobile phone 835 MHz electromagnetic fields in Drosophila at SAR 1.6 W/kg and SAR 4.0 W/kg. At SAR 1.6 W/kg, more than 90% of flies remained viable even after the 30 h exposure, while at SAR 4.0 W/kg viability dropped from the 12 h exposure. Both exposure levels triggered a stress response, increased reactive oxygen species production, and activated ERK and JNK signaling, but not p38 kinase signaling. SAR 4.0 W/kg strongly activated JNK signaling, expression of apoptotic genes, and amplified the number of apoptotic cells in the fly brain.
Nittby H et al. · 2008
Researchers exposed Fischer 344 rats to radiation from a GSM mobile test phone at 1,800 MHz for 6 hours and then analyzed gene expression in the cortex and hippocampus. Four rats were exposed in an anechoic chamber one at a time, and four control rats were kept in the same chamber for the same duration without exposure. Gene ontology analysis found highly significant changes in gene categories related to membrane functions in both brain regions.
Nittby H et al. · 2008
Researchers exposed rats to cell phone radiation at 1,800 MHz for 6 hours and found significant changes in brain gene activity. The genetic alterations affected genes controlling cell membranes and cellular communication in the cortex and hippocampus, the same brain regions where previous studies documented blood-brain barrier damage.
Ammari M et al. · 2008
Researchers investigated the effects of sub-chronic and chronic head-only exposure to 900 MHz GSM signals on spatial memory in male rats. Rats were exposed for 45 minutes per day at a SAR of 1.5 W Kg(-1), or 15 minutes per day at a SAR of 6 W Kg(-1), for either 8 or 24 weeks, and then tested in a radial-arm maze. Spatial memory was unaffected in the exposed rats, while scopolamine-treated positive control rats showed a deficit in the spatial memory task.
Ammari M et al. · 2008
French researchers exposed rats to 900 MHz cell phone radiation (the same frequency used by GSM phones) for either 8 or 24 weeks, then tested their spatial memory using a maze. The rats showed no memory problems compared to unexposed rats, even at radiation levels up to four times higher than current safety limits. This suggests that chronic cell phone radiation exposure may not impair spatial learning and memory functions in the brain.
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.
Paparini A et al. · 2008
Mice were exposed to GSM 1800 MHz signal for 1 hour at a whole body SAR of 1.1 W/kg. Gene expression was measured in whole brain using microarrays with over 22,600 probe sets. Comparison of sham and exposed animals showed no significant difference in gene expression. With less stringent analysis, 75 genes appeared modulated but were not confirmed by real-time PCR.
Paparini A et al. · 2008
Researchers exposed mice to GSM cell phone radiation (1800 MHz) for one hour and analyzed gene expression changes in brain tissue using advanced genetic screening techniques. They found no significant changes in brain gene expression patterns, even when using less strict analysis methods that initially suggested 75 genes might be affected. This study suggests that short-term exposure to cell phone-level radiation may not cause major genetic changes in brain tissue.
Huang TQ, Lee MS, Oh E, Zhang BT, Seo JS, Park WY. · 2008
They assessed cell proliferation, cell cycle progression, DNA damage, and gene expression. RF exposure did not significantly change cell numbers, cell cycle distribution, or DNA damage levels. Genome-wide analysis found no genes changed more than two-fold, but ten genes changed 1.3- to 1.8-fold, including down-regulation of CXCR3 and IL1R2.
Curcio G et al. · 2008
The study investigated whether repeated brief exposures to a GSM mobile phone signal had a cumulative effect on psychomotor functions. After each of 3 15-min exposures, both an acoustic simple reaction time task and a sequential finger tapping task were administered to subjects. No cumulative effects were detected, though there was a non-statistical trend toward shorter reaction times.