Hossain MI, Faruque MRI, Islam MT. · 2015
Researchers used computer simulation to study how distance and angle between a human head model and a phone antenna affect specific absorption rate (SAR). Increasing the distance between the head model and antenna decreased SAR values. Increasing the inclination angle did not reduce SAR values in all cases. The study also examined the effect of a metal-glass phone casing on SAR near the head model. Antenna performance was checked by measuring return loss in all cases.
Gramowski-Voß A et al. · 2015
Researchers exposed differentiating murine cortical networks on multiwell microelectrode arrays to an extremely low-frequency electromagnetic field with alternating 10 and 16 Hz modulation on a 150 MHz carrier. The development of cortical activity was accelerated under these exposure conditions. The percentage of neurons in the co-culture increased without changing the total cell count, indicating enhanced neurogenesis. ELEMF exposure selectively promoted the proliferation of GABAergic neurons, increasing their proportion. The exposure also stimulated electrical network activity and intensified burst structure.
Carlberg M, Hardell L. · 2015
Researchers conducted a pooled analysis of two case-control studies on meningioma diagnosed during 1997-2003 and 2007-2009. In the highest decile of use (>3,358 hours), odds ratios were 1.5 for mobile phones and 2.0 for cordless phones. No association was found for ipsilateral use or anatomical tumor location.
Aerts S, Plets D, Thielens A, Martens L, Joseph W. · 2015
Researchers assessed RF-EMF exposure of a mobile-phone user connected to either an outdoor macrocell or an in-train small cell while traveling on a train. The study used the absorbed-dose concept combining base station downlink exposure with mobile-phone uplink exposure. For GSM at 1800 MHz, connecting to a small cell reduced brain exposure by a factor of 35 and whole-body exposure by a factor of 11.
Schoeni A, Roser K, Röösli M · 2015
Researchers conducted a prospective cohort study with 439 adolescents who completed verbal and figural memory tasks at baseline and after one year. Wireless device use was assessed by questionnaire and operator recorded mobile phone use data for a subgroup of 234 adolescents, and RF-EMF dose measures for the brain and whole body were computed. Higher cumulative call duration and RF-EMF brain and whole-body doses were linked to lower figural memory scores. No exposure-response associations were observed for sending text messages and gaming, and memory change over one year was negatively associated with wireless phone use and more strongly with RF-EMF dose.
Şahin A et al. · 2015
The study consisted of control, sham-exposed, and EMF-exposed groups with six rats in each. The EMF-exposed group received 900 MHz EMF for 1 hour per day for 30 days while the sham group was placed in the same jar without exposure. Stereological analysis revealed a significantly lower total number of pyramidal neurons in the cornu ammonis of EMF-exposed rats compared to both control and sham groups, and histopathology showed abnormal cells with dark cytoplasm and shrunken morphology.
Zhao YL et al. · 2015
Mice were exposed to whole-body 2100 MHz microwaves at SARs of 0.45, 1.8, and 3.6 W/kg for 1 hour daily for 8 weeks. GO analysis showed the genes were involved in metabolic processes, cellular metabolic processes, regulation of biological processes, macromolecular metabolic processes, biosynthetic processes, cellular protein metabolic processes, transport, developmental processes, and cellular component organization. KEGG pathway analysis revealed enrichment in ribosome, Alzheimer's disease, Parkinson's disease, long-term potentiation, Huntington's disease, and Neurotrophin signaling pathways.
Masuda H et al. · 2015
The cortex tissue targeted was locally exposed to 1439 MHz RF using a figure-8 loop antenna at an averaged specific absorption rate of 2.0 W/kg in the target area for 50 min. Three microcirculatory parameters related to cerebral inflammation were measured by the cranial window method in real-time under RF exposure. No extravasation of intravenously injected fluorescent dye was observed during RF exposure. There was no significant difference either in pial venule blood flow velocity or diameter between exposed and sham-exposed rats. Histological evaluation for the brain immediately after RF exposure did not reveal any serum albumin leakage sites or degenerate neurons.
Furtado-Filho OV et al. · 2015
Researchers exposed young rats to 950 MHz ultra-high-frequency electromagnetic radiation to measure oxidative damage to DNA, proteins, and lipids in the left and right cerebral cortex. Radiation exposure lasted 30 minutes per day for up to 27 days, with a specific absorption rate ranging from 1.32 to 1.14 W/kg. In neonates, no modification of the biomarkers tested was detected, while 6-day-old exposed rats showed increased carbonylated proteins in the right cerebral cortex and decreased blood glucose. The researchers concluded that the elevated carbonylated proteins in the right cerebral cortex did not appear to be a consequence of oxidative stress.
Zuo WQ, Hu YJ, Yang Y, Zhao XY, Zhang YY, Kong W, Kong WJ. · 2015
Researchers used spiral ganglion neurons from neonatal Sprague Dawley rats to investigate whether inflammation might increase sensitivity to damage from mobile phone electromagnetic radiation. Radiofrequency electromagnetic radiation alone could not directly induce DNA damage in normal spiral ganglion neurons. The study suggests that sensitivity of spiral ganglion neurons to damage caused by mobile phone electromagnetic radiation may increase in a lipopolysaccharide-induced inflammation model.
Wang X et al. · 2015
Researchers exposed Neuro-2a cells to 900 MHz GSM signals at specific absorption rates of 0, 0.5, 1, or 2 W/kg for 24 hours, with or without silencing of the DNA repair enzyme OGG1. Without OGG1 silencing, 2 W/kg RF-EMFs induced oxidative DNA base damage, and with OGG1 silencing, damage was observed at exposures as low as 1 W/kg. Increases in oxidative DNA base damage were accompanied by similar increases in reactive oxygen species, but neither DNA strand breakage nor altered cell viability was observed.
Wang LF et al. · 2015
Researchers used an in vitro blood-brain barrier model exposed to microwave radiation at 50 mW/cm2 for 5 minutes to study how the VEGF/Flk-1-ERK pathway relates to barrier injury. Microwave radiation caused tight junctions to broaden and fracture, with decreased TEER values and increased HRP permeability. When Flk-1 and MEK1/2 inhibitors were applied, the structure and function of the blood-brain barrier were recovered.
Tang J et al. · 2015
Researchers exposed 108 male Sprague-Dawley rats to a 900 MHz, 1 mW/cm2 electromagnetic field for 14 or 28 days at 3 hours per day, with some rats left unexposed as a sham group. Rats exposed for 28 days crossed platforms less often and spent less time in the target quadrant than rats exposed for 14 days and unexposed rats. Twenty-eight days of exposure was also associated with cellular edema, neuronal cell organelle degeneration, and albumin and HO-1 extravasation in the hippocampus and cortex. The researchers found that 28 days of EMF exposure induced the expression of mkp-1, resulting in ERK dephosphorylation.
Roggeveen S, van Os J, Lousberg R · 2015
Researchers investigated whether third generation mobile phone radiation peaks produce event-related potentials in the brain. Thirty-one healthy females took part in a single-blind, cross-over design where a 15 minute mobile phone exposure was compared to two 15 minute sham phone conditions. When the phone was placed at the ear, an enlarged cortical reactivity was found in the frontal and central cortical regions, but not when it was placed at the heart.
Roggeveen S, van Os J, Viechtbauer W, Lousberg R · 2015
Researchers investigated whether placement of a 3G dialing mobile phone causes direct changes in EEG activity compared to placement of a sham phone. Thirty-one healthy females each participated on two days, with the phone placed at the ear on one day and the chest on the other. Significant radiation effects were found for the alpha, slow beta, fast beta, and gamma bands, with ear placement showing significant results and chest placement not.
Megha K et al. · 2015
Researchers exposed Fischer rats to 900 MHz and 1800 MHz microwave radiation for 30 days at 2 hours per day, 5 days per week, with specific absorption rates of 5.953 × 10−4 and 5.835 × 10−4 W/kg respectively. Levels of dopamine, norepinephrine, epinephrine, and serotonin were measured in the hippocampus using LC–MS/MS. Exposed animals showed significant reductions in DA, NE, E and 5-HT, and significant downregulation in mRNA expression of TH, TPH1, and TPH2 compared with sham-exposed animals (p < 0.05).
Lustenberger et al. · 2015
The study investigated how much variation exists between individuals and within the same individual in response to pulsed radiofrequency electromagnetic field exposure during sleep. The EEG analysis showed exposure-related increases in the delta-theta frequency range at several fronto-central electrodes, but no differences in the spindle frequency range. Reproducible within-subject effects on sleep spindle and delta-theta activity were not observed, and it remained unclear whether a biological trait of how subjects' brains react to RF EMF exists.
Ghosn R et al. · 2015
Researchers recorded resting EEG in 26 healthy young subjects under sham and real RF exposure conditions in a double-blind, counterbalanced, crossover design. Compared with the sham session, the exposure session showed a statistically significant decrease of alpha band spectral power during the closed-eyes condition. This effect persisted in the postexposure session, and no significant changes were detected in electrode impedance, salivary cortisol, or caffeine between conditions.
Deshmukh PS et al. · 2015
Researchers exposed male Fischer rats to microwave radiation for 180 days at 3 different frequencies, namely, 900, 1800 MHz, and 2450 MHz. The study investigated effects on cognitive function, heat shock protein 70 (HSP70), and DNA damage in rat brain. The results showed declined cognitive function, elevated HSP70 level, and DNA damage in the brains of microwave-exposed animals. The researchers concluded that chronic low-intensity microwave exposure in the frequency range of 900 to 2450 MHz may cause hazardous effects on the brain.
Danker-Hopfe H et al. · 2015
Researchers conducted a double-blind, randomized, sham-controlled cross-over study to examine whether electromagnetic fields from GSM 900 and WCDMA/UMTS devices affected sleep. Thirty healthy young men between 18 and 30 years old were each exposed three times per exposure condition while their sleep was recorded. The only consistent finding across individuals was an increase of stage R sleep under GSM 900 MHz exposure in 9 of 30 subjects and under WCDMA/UMTS exposure in 10 of 30 subjects.
Bodera P et al. · 2015
Researchers measured malondialdehyde (MDA), a marker of lipid peroxidation, in the blood, liver, kidneys, and brain of Wistar rats that were healthy or had inflammation, and exposed them repeatedly to 1800 MHz EMF. The exposure was repeated five times for 15 minutes and was studied both alone and combined with the opioid painkiller tramadol. MDA levels were slightly elevated in the blood, kidney, and brain of healthy rats in EMF-exposed groups treated with tramadol, while MDA in the liver remained at the same level across all groups. Overall, results for healthy rats and animals with inflammation did not differ significantly.
Murbach et al. · 2014
Researchers evaluated three hypotheses about how radiofrequency exposure could affect EEG by using numerical simulations and experimental assessments with phantoms and anatomical human models. They found that induced fields cause less than a 20% increase in 10 g-averaged SAR, that worst-case electrode placement raises skin temperature by at most 0.31 °C and brain temperature by less than 0.1 °C, and that temperature ripples from RF pulses are below 0.001 °C for GSM-like signals and below 0.004 °C for higher pulse energy. These local short-term temperature elevations are unlikely to change brain physiology during the time period from minutes to several hours after exposure. Thus, the mechanism of interaction between RF and changes in the EEG power spectrum remains unknown.
Hsu MH et al. · 2014
Researchers conducted a population-based study using cancer registry data from 2000 to 2009 and cell phone user statistics from the National Communication Commission. The National Cancer Registry recorded 4 incidences and 4 deaths due to malignant neoplasms in Taiwan during 2000-2009. Ten years of observational data showed no significant effect of intensive cell phone use on the incidence rate or mortality of malignant brain tumors in Taiwan. The authors concluded they detected no correlation between cell phone use and malignant brain tumor morbidity or mortality in Taiwan.
Shirai T et al. · 2014
Researchers exposed rats to 2.14 GHz W-CDMA signals for 20 hours a day over three generations. No abnormalities were observed in mother rats or offspring across any biological parameters including neurobehavioral function. The study used three SAR levels: high (<0.24 W/kg), low (<0.08 W/kg), and sham exposure. Pregnant rats were exposed from gestational day 7 to weaning, and offspring were continuously exposed until 6 weeks of age.
Klose M et al. · 2014
Female Wistar rats from 14 days to 19 months were exposed in the head region for 2 hours per day, 5 days per week to a GSM-modulated 900 MHz field at SAR values of 0, 0.7, 2.5, and 10 W/kg. Four behavioral and learning tests (rotarod, Morris water maze, 8-arm radial maze, open field) were performed three times in juvenile, adult, and presenile rats. No profound differences were identified between exposure groups, though rotarod data showed significantly longer holding times for sham-exposed rats on some days, but these findings were not consistent. The results do not indicate harmful effects of long-term RF-EMF exposure begun at an early age on development, learning, and behavior, even at relatively high SAR values.
