Unknown authors · 2007
The paper discusses the phenomenon, mechanism, power requirement, pressure amplitude, and auditory thresholds of microwave hearing. Microwave pulse hearing involves electromagnetic waves from hundreds of MHz to tens of GHz, unlike normal hearing which uses sound pressure waves. The microwave auditory effect does not come from direct interaction with auditory nerves but from a thermoelastic wave launched by pulse absorption in soft tissues. This thermoelastic wave travels by bone conduction to the inner ear and activates cochlear receptors like normal hearing. The paper emphasizes human exposures to wireless communication fields and MRI coils.
Unknown authors · 2007
Researchers tested 84 young healthy adults on two forced-choice tasks to detect a GSM mobile phone field at 902 MHz pulsed at 217 Hz. Participants completed 600 trials across three conditions per task with a monetary prize for 75% accuracy, but performance was no better than chance and no one won. Two participants scored 97% and 94% in one condition but failed to replicate the result in a retest one month later. Six participants who reported being able to perceive the field performed no better than others.
Unknown authors · 2007
Researchers studied the effect of long-term exposure to low-intensity electromagnetic radiation from GSM base stations on house sparrows during breeding season in six Belgian residential districts. They sampled 150 point locations across the six areas to examine variation in male house sparrow numbers and electromagnetic radiation strength. The number of male house sparrows was negatively and highly significantly related to electric field strength from 900 and 1800 MHz downlink bands. This negative relationship was consistent across all six study areas despite differences in bird numbers and radiation levels.
Unknown authors · 2007
Unknown authors · 2007
Researchers exposed murine L929 fibroblasts, rat C6 glioblastoma cells, human SH-SY5Y neuroblastoma cells, and rat primary astrocytes to 872 MHz RF radiation. Cells were exposed for 2, 8, or 24 hours to continuous wave or GSM-modulated signals at specific absorption rates of 1.5, 2.5, or 6.0 W/kg. ODC activity in rat primary astrocytes decreased significantly at 1.5 and 6.0 W/kg with both signal types. Secondary cell lines showed generally no change in ODC activity.
Shirai T et al. · 2007
Pregnant F344 rats received a single dose of ENU on gestational day 18. Rats were exposed to a 1.95-GHz W-CDMA signal for 90 minutes a day, 5 days a week, for 104 weeks starting at 5 weeks of age. Brain average specific absorption rates were designed to be .67 and 2.0 W/kg for low and high exposures, respectively. The incidence and numbers of brain tumors in female rats exposed to 1.95-GHz W-CDMA signals showed tendencies to increase but without statistical significance, and overall no significant increase in incidences or numbers was detected in either males or females.
Schmid G et al. · 2007
A numerical model of the human middle and inner ear was developed at 0.1 mm resolution based on a real human tissue sample. The model was inserted into a commercial head model and FDTD computations were run for handheld device exposures from 400 to 3700 MHz. Highest absorption occurred at 400 MHz with 166 microW in the labyrinth and 12 microW in the vestibulocochlear nerve for a 500 mW device. For typical mobile phone frequencies (900 MHz and 1850 MHz) and output power values (250 mW and 125 mW), absorbed RF power was more than one order of magnitude lower than the values given above. The researchers concluded that temperature-related biologically relevant effects from typical handheld devices are unlikely.
Schmid G et al. · 2007
Researchers measured the dielectric properties of 20 freshly removed human pineal glands less than 20 hours after death. They developed a high-resolution numerical model of the brain region around the pineal gland based on a real human tissue sample. FDTD computations were performed for handheld device exposures close to the head at 400-1850 MHz. The highest absorption was at 400 MHz with 11 microW absorbed in a 96 mg gland from a 500 mW device. At 900 MHz and 1850 MHz, absorption was lower by factors of 4.2 and 36 respectively.
Preece AW, Georgiou AG, Dunn EJ, Farrow S · 2007
Field strengths in exposed villages reached up to 0.30 (Volts/Vm(-1) metre) from the 17.6 MHz military transmissions and up to 1.4 Vm(-1) from other sources, while the control village measured below 0.01 Vm(-1). Compared with the control village, exposed residents reported significantly more migraine, headache, and dizziness, and had poorer scores on all eight SF-36 health domains. The authors noted heightened risk perception, especially for noise and electromagnetic pollution, and suggested the symptom excess was more likely due to antenna visibility or aircraft noise.
Parazzini M et al. · 2007
The GUARD project involved nine European centers and aimed to assess potential changes in auditory function from low-intensity EMFs produced by GSM cellular phones. Participants were healthy young adults without any evidence of hearing or ear disorders. Auditory function was assessed immediately before and after EMF exposure using hearing threshold level, transient otoacoustic emissions, distortion product otoacoustic emissions, and auditory brainstem response. The study used a double-blind design with genuine and sham exposures separated by at least 24 hours. Exposure consisted of speech at a typical conversational level delivered via an earphone to one ear, plus genuine or sham EMF exposure from a consumer cellular phone at full power for 10 min.
Oftedal G, Straume A, Johnsson A, Stovner L · 2007
Seventeen eligible individuals who experienced symptoms in an open provocation test took part in a double-blind, randomized provocation study with cross-over design. Sixty-five pairs of sham and mobile phone RF exposures were conducted. The increase in pain or discomfort on visual analogue scales was 10.1 in RF sessions and 12.6 in sham sessions (P=0.30). Changes in heart rate or blood pressure were not related to the type of exposure (P: 0.30-0.88). The study gave no evidence that RF fields from mobile phones may cause head pain or discomfort or influence physiological variables.
Masuda H et al. · 2007
Researchers exposed rat heads to 1439 MHz RF-EMF for 10 minutes at three intensity doses of 0.6, 2.4, and 4.8 W/kg BASAR. They measured blood-brain barrier permeability, leukocyte behavior, plasma velocity, and vessel diameter using a closed cranial window method. No extravasation of intravenously injected dyes from pial venules was found at any BASAR level. No significant changes in the number of endothelial-adhering leukocytes after exposure were found. Plasma velocities and vessel diameters remained constant within the physiological range throughout each exposure.
Masuda H et al. · 2007
Researchers exposed the heads of rats for four weeks (60 min/day, 5 days/week) to RF-EMF at 2.4 W/kg of brain averaged specific absorption rate (BASAR). They measured blood-brain barrier permeability, leukocyte behavior, and plasma velocity using a closed cranial window method. No extravasation of dyes from pial venules was found, no significant changes in endothelial-adhering leukocytes occurred, and plasma velocity remained constant within the physiological range. These findings suggest that there were no effects on the cerebral microcirculation under the given RF-EMF exposure conditions.
Klaeboe L, Blaasaas KG, Tynes T. · 2007
Researchers tested whether radio-frequency electromagnetic fields from mobile phones increase the incidence of gliomas, meningiomas, and acoustic neuromas in adults. They collected detailed mobile phone use information from 289 glioma patients, 207 meningioma patients, 45 acoustic neuroma patients, and 358 controls. For regular mobile phone use defined as at least once a week for at least six months, the odds ratios were 0.6 for gliomas, 0.8 for meningiomas, and 0.5 for acoustic neuromas. No increasing trend was observed for gliomas or acoustic neuromas with longer duration, time since first use, or cumulative use. The results indicate that mobile phone use is not associated with an increased risk of these tumors.
Kan P, Simonsen SE, Lyon JL, Kestle JR. · 2007
Researchers conducted a meta-analysis of nine case-control studies with 5,259 brain tumor cases and 12,074 controls to examine cellular phone use and brain tumor risk. The pooled analysis showed an overall odds ratio of 0.90 with a 95% confidence interval of 0.81 to 0.99 for cellular phone use and brain tumor development. For long-term users of ten years or more, the pooled odds ratio was 1.25 with a 95% confidence interval of 1.01 to 1.54 based on five studies. No increased risk was observed for analog or digital cellular phone users.
Glover PM, Eldeghaidy S, Mistry TR, Gowland PA. · 2007
Researchers used an MRI gradient coil to produce a time-varying magnetic field of 0.5 kHz and peak field of approximately 8.7 T/s in the human brain. Visual evoked potentials were recorded from occipital sites O1 and O2 in response to a checkerboard stimulus before, during, and after a 10-minute exposure period in seven subjects. No significant effects were found on the peak amplitude or latency of the VEP P100 responses at O1 and O2.
Canseven AG, Keskil ZA, Keskil S, Seyhan N. · 2007
Researchers tested whether a 50 Hz, 0.2 mT magnetic field given before or after drug administration affected seizures induced by pentylenetetrazol in mice. The magnetic field was generated by a pair of Helmholtz coils and seizures were induced by intraperitoneal injection of pentylenetetrazol at 60 mg/kg. Forty-eight adult female mice were used and latency to seizure, total seizure duration, and mortality were recorded. Neither pre- nor post-drug magnetic field exposure had any effect on seizures or mortality rates.
Terao Y et al. · 2007
Researchers used a double-blind, counterbalanced crossover design with 10 normal subjects to test saccade performance before and after 30 minutes of mobile phone EMF exposure or sham exposure. They also measured hand reaction time to a visual signal. Saccade task parameters were unchanged after real or sham exposure, except for VGS and MGS latencies which also did not differ between exposure conditions. Hand reaction time shortened with repeated trials similarly for both exposures. The authors concluded that 30 minutes of mobile phone exposure has no significant short-term effect on saccade performance.
Stefanics G et al. · 2007
Each participant underwent a 10-minute exposure to 900 MHz pulsed EMF from a commercial Nokia 6310 mobile phone. Fifteen participants received genuine EMF exposure and fifteen received sham exposure in a double-blind, counterbalanced order. No significant differences were found in the latency of ABR waves I, III, and V before and after either genuine or sham exposure. The authors suggest that, in their experimental conditions, a single 10-minute exposure to 900 MHz EMF from a commercial mobile phone does not produce measurable immediate effects on the latency of auditory brainstem waves I, III and V.
Platano D et al. · 2007
Researchers studied the non-thermal effects of radiofrequency electromagnetic fields on barium currents through voltage-gated calcium channels in primary cultures of rat cortical neurons using the patch-clamp technique. Neurons were exposed for one to three periods of 90 seconds to 900 MHz continuous wave or GSM-modulated signals during whole-cell recording at specific absorption rates of 2 W/kg for both modulation types. Single or multiple acute exposures to either continuous wave or GSM-modulated 900 MHz fields did not significantly alter the current amplitude or the current-voltage relationship through voltage-gated calcium channels.
Perentos N, Croft RJ, McKenzie RJ, Cvetkovic D, Cosic I · 2007
Researchers used a fully counterbalanced cross-over design with 12 participants to test mobile phone-like RF exposure effects on EEG. Exposures lasted 15 minutes using a dipole antenna more closely resembling a real GSM handset.
Joubert V, Leveque P, Cueille M, Bourthoumieu S, Yardin C. · 2007
Researchers exposed primary cultured neurons from embryonic Wistar rat cortices to a 900-MHz GSM field for 24 hours at 0.25 W/kg SAR. Apoptosis was measured immediately and 24 hours after exposure using DAPI staining, TUNEL/PI flow cytometry, and caspase-3 fluorimetry. No statistically significant difference in apoptosis rate was found between exposed and control neurons at either time point. All three assessment methods gave concordant results.
Irlenbusch L et al. · 2007
Researchers measured the visual discrimination threshold in 33 subjects during both RF and sham exposures. Each experiment consisted of two 30-minute periods with a 5-minute break, and the threshold was recorded every 10 seconds. The RF exposure used a 902.4 MHz GSM signal pulsed at 217 Hz with a power flux density of 1 W/m². No statistically significant difference in the threshold was found between RF and sham exposures.
Inomata-Terada S et al. · 2007
They also assessed short-interval intracortical inhibition reflecting GABAergic interneuron function using paired-pulse TMS. No effects of exposure were found on MEPs or SICI in healthy volunteers, and no effects on MEPs were observed in two multiple sclerosis patients despite conduction block after a hot bath.
Haarala C et al. · 2007
Researchers studied the effects of continuous wave and pulsed wave electromagnetic fields on cognitive function in 36 healthy male subjects. Subjects performed cognitive tasks during exposure to continuous wave, pulsed wave, and sham fields, with left- and right-sided exposure in a double-blind design. No effects were found between EMF conditions, hemisphere exposures, or between the control and experimental groups.
