Brain & Nervous System

Influence of dentures on SAR in the visible Chinese human head voxel phantom exposed to a mobile phone at 900 and 1800 MHz.

Yu D, Zhang R, Liu Q. · 2012

Do TETRA (Airwave) base station signals have a short-term impact on health and well-being? A randomized double-blind provocation study.2

Wallace D et al. · 2012

Researchers conducted a randomized double-blind provocation study to test whether short-term exposure to a TETRA base station signal affects health and well-being. Fifty-one electrosensitive individuals and 132 matched controls took part, with 48 electrosensitive and 132 control participants completing double-blind tests in a screened semianechoic chamber. Under double-blind conditions, no differences were found on any measure between TETRA and sham exposure, and neither group could detect the signal above chance. When conditions were not double-blind, electrosensitive participants reported feeling worse and more severe symptoms during TETRA exposure. The researchers suggest that adverse symptoms in electrosensitive individuals are due to the belief of harm from TETRA base stations.

Use of wireless phones and serum β-trace protein in randomly recruited persons aged 18-65 years: a cross-sectional study

Söderqvist F, Carlberg M, Zetterberg H, Hardell L · 2012

Three hundred and fourteen people aged 18-65 years were recruited from Örebro, Sweden, using the population registry. They used linear regression analyses adjusted for covariates to examine associations between serum β-trace protein and short- and long-term wireless phone use. Overall, no statistically significant association was found, but a negative association emerged for long-term use in the 18-30 year age group.

Effect of in utero wi-fi exposure on the pre- and postnatal development of rats.

Poulletier de Gannes F et al. · 2012

Researchers exposed pregnant rats to a 2450 MHz Wi-Fi signal for 2 hours per day, 6 days per week, for 18 days at whole-body specific absorption rates of 0.08, 0.4, and 4 W/kg. The prenatal study examined fetuses delivered by caesarean section from five females per group, and dams with offspring were observed for 28 days after delivery with 15 females per group. No abnormalities were noted in pregnant rats and no significant signs of toxicity were observed in pre- and postnatal development of pups, even at the highest exposure level of 4 W/kg.

EHS subjects do not perceive RF EMF emitted from smart phones better than non-EHS subjects.

Kwon MK, Kim SK, Koo JM, Choi JY, Kim DW. · 2012

The study used a double-blind design with 17 EHS and 20 non-EHS volunteers exposed to real and sham RF-EMF sessions. There was no indication that EHS subjects perceive RF-EMFs better than non-EHS subjects. Exposure used a WCDMA module at 1950 MHz with an average power of 24 dBm and a specific absorption rate of 1.57 W/kg for 32 min.

Use of mobile phones and cordless phones is associated with increased risk for glioma and acoustic neuroma.

Hardell L, Carlberg M, Hansson Mild K. · 2012

Researchers conducted a meta-analysis of the Hardell group and Interphone studies on mobile phone use and brain tumours. The meta-analysis found an odds ratio of 1.71 for glioma in the temporal lobe in the latency group of 10 years or more. For ipsilateral mobile phone use with a latency of 10 years or more, the odds ratio for acoustic neuroma was 1.81. The analysis also reported an odds ratio of 2.29 for ipsilateral mobile phone use of 1640 hours or more, and an odds ratio of 2.55 for ipsilateral cumulative use of 1640 hours or more. The Hardell group studies also found that cordless phone use increased the risk for glioma and acoustic neuroma.

Effects of GSM 900 MHz on Middle Cerebral Artery Blood Flow Assessed by Transcranial Doppler Sonography.

Ghosn R et al. · 2012

Volunteers participated in a double-blind, crossover study with sham and real GSM 900 MHz mobile phone exposure sessions lasting 20 minutes each. Middle cerebral artery blood flow velocity, pulsatility index, and resistance index were measured noninvasively with transcranial Doppler sonography before, during, and after exposure. No significant changes were detected in studied variables in middle cerebral arteries during sham or real exposure.

Cohort study on the effects of everyday life radio frequency electromagnetic field exposure on non-specific symptoms and tinnitus.Environ Int. 38(1):29-36, 2012

Frei P et al. · 2012

Researchers enrolled 1375 randomly selected participants from Basel, Switzerland, in 2008 with a one-year follow-up and 82% participation rate. Far-field environmental RF-EMF exposure was predicted using a validated model, and near-field exposure was assessed via self-reported phone use and operator data. For participants in the top decile of far-field exposure compared to those below the median, the change in von Zerssen score was -0.12 (95% CI -1.79 to 1.56) and the change in HIT-6 score was -0.37 (95% CI -1.80 to 1.07). Exposure to near-field sources and changes in exposure over time were not related to non-specific symptoms, and no association was observed for tinnitus.

Mobile phone use and incidence of glioma in the Nordic countries 1979-2008: consistency check.

Deltour I et al. · 2012

Researchers analyzed annual age-standardized glioma incidence rates in men and women aged 20 to 79 years in the Nordic countries from 1979 to 2008 using joinpoint regression, including 35,250 cases. Incidence rates decreased in young men since 1987, remained stable in middle-aged men, and increased slightly in older men, with an overall annual percent change of 0.4% in men and 0.3% in women. Simulations indicated that relative risks of 2.0 for up to 15 years, 1.5 for up to 10 years, and 1.2 for up to 5 years for all users, as well as risks of 2.0 for up to 5 years for heavy users, were incompatible with observed trends.

Acute effects of electromagnetic fields emitted by GSM mobile phones on subjective well-being and physiological reactions: a meta-analysis.

Augner C, Gnambs T, Winker R, Barth A. · 2012

The meta-analysis aimed to clarify whether RF-EMF influence well-being in self-reported sensitive persons and non-sensitive people. It included 17 studies with 1174 participants and combined the single effects of subjective and objective outcomes into a single population parameter. No significant impact of short-term RF-EMF exposure was found on any parameter.

Cognitive and physiological responses in humans exposed to a TETRA base station signal in relation to perceived electromagnetic hypersensitivity.

Wallace D et al. · 2012

Researchers exposed Fifty-one people who reported perceived sensitivity to electromagnetic fields and 132 controls to a 420 MHz TETRA signal at 10 mW/m² and sham conditions under double-blind conditions. Cognitive measures of short-term memory, working memory, and attention were administered while physiological responses including blood volume pulse, heart rate, and skin conductance were monitored. No differences in cognitive performance or physiological responses were observed between TETRA exposure and sham in either group.

Exposure to radiofrequency electromagnetic fields and sleep quality: a prospective cohort study.

Mohler E et al. · 2012

Researchers conducted a prospective cohort study with 955 participants aged 30 to 60 years to investigate whether sleep quality is affected by mobile phone use or other RF-EMF sources. Sleep quality and daytime sleepiness were assessed using standardized questionnaires at baseline in May 2008 and follow-up in May 2009. In longitudinal analyses, neither operator-recorded nor self-reported mobile phone use was associated with sleep disturbances or daytime sleepiness.

No effects of short‐term GSM mobile phone radiation on cerebral blood flow measured using positron emission tomography

Kwon MS et al. · 2012

Researchers investigated effects of 902.4 MHz GSM radiation on cerebral blood flow using PET with 15O-water tracer. Fifteen young healthy men were exposed to radiation at three head locations and sham exposure while performing a visual task. Exposure caused slight ear canal temperature rise but did not affect brain hemodynamics or task performance. Results showed no evidence of acute effects on cerebral blood flow.

Effects of electromagnetic radiation produced by 3G mobile phones on rat brains: Magnetic resonance spectroscopy, biochemical, and histopathological evaluation

Dogan M et al. · 2012

Rats were randomly assigned to an exposed group (n=9) and a control group (n=9), with the exposed group subjected to electromagnetic radiation for 20 days. Researchers measured choline, creatinin, and N-acetylaspartate levels by magnetic resonance spectroscopy, catalase and glutathione peroxidase activities by spectrophotometry, and apoptosis by histopathology. No significant differences were found in NAA/Cr, Cho/Cr, or NAA/Cho ratios between the exposed and control groups. Oxidative stress parameters and apoptotic cell counts also showed no significant differences between groups.

Effects of mobile phone signals over BOLD response while performing a cognitive task

Curcio G et al. · 2012

The study aimed to investigate the effects of GSM signal exposure on brain BOLD response and its time course during a Go-NoGo task. Participants were tested twice, once with real GSM radiofrequency signal exposure and once with a sham exposure as a placebo condition. BOLD response and reaction times were measured before and after exposure while participants performed the task. Reaction times to the somatosensory task did not change with real versus sham exposure, and Go responses activated the inferior parietal lobule, insula, precentral and postcentral gyri similarly after both exposures with no significant ROI effects.

Prenatal and Postnatal Cell Phone Exposures and Headaches in Children.

Sudan M, Kheifets L, Arah O, Olsen J, Zeltzer L. · 2012

Researchers used data from the Danish National Birth Cohort, which enrolled pregnant women from 1996 to 2002, and assessed children at age seven via maternal questionnaire. They analyzed 52,680 children using multivariable adjusted models to relate prenatal only, postnatal only, or both prenatal and postnatal cell phone exposure to migraines and headache-related symptoms. Children with both prenatal and postnatal exposure had higher odds of migraines (OR 1.30, 95% CI 1.01-1.68) and headache-related symptoms (OR 1.32, 95% CI 1.23-1.40) compared to unexposed children.

The sound of a mobile phone ringing affects the complex reaction time of its owner.

Zajdel R et al. · 2012

Researchers compared reaction times of 42 healthy students during instruction, control without phone, and a session with their mobile phone ringing. Reaction times were 597 ms in control, 633 ms with phone ringing, and 673 ms in instruction, with significant differences across sessions (p < 0.001). Women had longer reaction times than men in instruction and mobile sessions, while men were significantly faster in those sessions; no gender difference appeared in control.

The Heritability and Genetic Correlates of Mobile Phone Use: A Twin Study of Consumer Behavior.

Miller G, Zhu G, Wright MJ, Hansell NK, Martin, NG · 2012

Researchers analyzed self-reported mobile phone use, intelligence, and personality traits in two samples of Australian teenaged twins totaling 1,036 individuals. ACE modeling showed substantial heritabilities for voice call frequency (.60 and .34) and text message frequency (.53 and .50), while shared family environment had much weaker effects. Multivariate modeling revealed negative genetic correlations between talking/texting frequency and intelligence (around -.17) and positive genetic correlations with extraversion (about .20 to .40).

Mobile phone use and glioma risk: comparison of epidemiological study results with incidence trends in the United States.

Little MP et al. · 2012

Researchers compared glioma incidence trends in the United States with risks reported in the Swedish and Interphone studies. US glioma incidence rates remained essentially stable over a period coinciding with a large rise in mobile phone use. Predicted rates based on the Swedish study were at least 40% higher than observed, while predictions using the Interphone study could match the observed data.

A population-based case-control study of radiofrequency exposure in relation to childhood neoplasm.

Li CY, Liu CC, Chang YH, Chou LP, Ko MC. · 2012

Researchers conducted a population-based case-control study in Taiwan of children aged 15 or younger diagnosed with neoplasms between 2003 and 2007. Exposure to radiofrequency radiation was estimated from the annual power density of mobile phone base stations in each township over the five years before diagnosis. Higher-than-median exposure was significantly associated with increased odds of all neoplasms combined, but not with leukemia or brain neoplasms individually.

Reported functional impairments of electrohypersensitive Japanese: A questionnaire survey.

Kato Y, Johansson O. · 2012

Effect of exposure to radio frequency radiation emitted by cell phone on the developing dorsal root ganglion of chick embryo: a light microscopic study.

Ingole IV, Ghosh SK. · 2012

Researchers exposed chick embryos to radiofrequency radiation emitted by a cell phone by varying the duration of exposure to create different doses. Light microscopic examination revealed that developing dorsal root ganglion neurons suffered damage that was dose dependent. The damage persisted even when exposure-free periods were given between exposures.

Use of Mobile and Cordless Phones and Survival of Patients with Glioma.

Hardell L, Carlberg M. · 2012

Researchers analyzed survival of glioma patients in relation to wireless phone use. For glioma overall, wireless phone use gave a hazard ratio of 1.1, and with more than 10-year latency the hazard ratio was 1.2. Low-grade astrocytoma showed a hazard ratio of 0.5, while glioblastoma showed a hazard ratio of 1.1, increasing to 1.3 with long latency. In the highest cumulative use tertile (>426 hours), glioblastoma hazard ratio was 1.2. The study included 1,251 malignant brain tumor cases diagnosed 1997–2003, followed until May 2012.

Are frequent dental x-ray examinations associated with increased risk of vestibular schwannoma?

Han YY et al. · 2012

Researchers compared 343 vestibular schwannoma patients to 343 matched controls and assessed their exposure to medical radiation and wireless phones. After adjusting for multiple factors, dental x-rays once a year (aOR = 2.27, 95% CI = 1.01-5.09) or every 2-5 years (aOR = 2.65, 95% CI = 1.20-5.85) were associated with higher vestibular schwannoma risk compared to less frequent exposure. Head or head-and-neck CT radiation exposure was associated with reduced risk (aOR = 0.52, 95% CI = 0.30-0.90). No association was found between cell phone or cordless phone use and vestibular schwannoma.

NMR imaging of cell phone radiation absorption in brain tissue.

Gultekin DH, Moeller L. · 2012

Researchers described a method for measuring absorbed electromagnetic energy from cell phone antennae into ex vivo brain tissue. The method uses NMR thermometry to measure temperature increases via resonance frequency shifts of hydrogen protons. NMR imaging revealed 3D thermal dynamics in ex vivo bovine brain tissue and gel under varying RF fields. Specific absorption rate measurements averaged over 1 mg and 10 s covered the total absorption volume. Fiber optic temperature sensors confirmed the accuracy of the NMR thermometry.