McNamee et al. · 2003
Researchers examined the effect of 24-hour continuous-wave and pulsed-wave 1.9 GHz radiofrequency fields on primary DNA damage and micronucleus induction in human leukocyte cultures. No significant differences in primary DNA damage were observed between sham controls and any exposed cultures when assessed by the alkaline comet assay immediately after exposure. Similarly, no significant differences were found in micronucleus incidence, micronucleated binucleated cells, binucleated cell frequency, or proliferation index between sham and exposed cultures.
Navarro EA, Sequra J, Portoles M, Gomez-Perretta de Mateo C · 2003
Researchers conducted a health survey near a cellular phone base station operating at DCS-1800 MHz in Murcia, Spain. Statistical analysis showed a significant correlation between declared symptom severity and measured power density, and the higher exposure group reported increased severity.
Moneda AP, Ioannidou MP, Chrissoulidis DP. · 2003
Researchers used a versatile eccentric-spheres model of the human head to investigate radio-wave absorption. Specific absorption rate maps showed hot spots in the eyes and near the center of the brain. Numerical results were presented for total, percentage, and gram-specific absorption using an exact analytical solution. The model focused on the brain and eyes of an adult or infant head.
Jayanand, Behari J, Lochan R. · 2003
Researchers exposed rats with sciatic neurectomy-induced osteoporosis to modulated pulsed electromagnetic fields at a 14 MHz carrier frequency modulated at 16 Hz with 10 V peak-to-peak amplitude. The exposure produced a statistically significant increase in bone mineral density and a deceleration in the bone resorption process in the femur and tibia. The authors suggest that this effective window of pulsed radio frequency fields may be used therapeutically for osteoporosis treatment.
Hocking B, Westerman R. · 2003
D'Costa H et al. · 2003
Researchers recorded EEG from ten awake subjects while a mobile phone behind the head emitted radiofrequency fields. The study tested a GSM phone at full radiated power and a phone in active standby mode, each with five active and five sham exposures in randomized five-minute intervals. The experiment was single-blind and compared average EEG band power between active and sham recordings. Statistical tests showed significant differences in the full-power trial for EEG alpha (8-13 Hz) and beta (13-32 Hz) bands. Analysis of median spectral power across 32 discrete frequencies found significant differences in 7 frequencies overall.
Bit-Babik G et al. · 2003
Researchers investigated the estimation of SAR in the human head and body from handheld mobile phones with hands-free accessories. The results show that the opposite is observed when proper dosimetric methods are employed. Human phantoms for such measurements should include the torso, not just the head, because the body strongly attenuates RF energy coupled into the accessory leads. Numerical simulations and experimental measurements agree that hands-free accessories decrease RF energy exposure in the human head.
Anderson V. · 2003
The study aimed to examine the scale and significance of differences in peak specific energy absorption rate (SAR) in the brains of children and adults exposed to radiofrequency emissions from mobile phones. Model analyses using a three-layered spherical head exposed to a dipole at 900 MHz showed that peak brain 10 g averaged SAR in 4, 8, 12, and 16 year olds increased by factors of 1.31, 1.23, 1.15, and 1.07 compared to an average adult. The researchers concluded that the relatively small scale of these increases does not warrant special precautionary measures for child mobile phone users.
Weisbrot D, Lin H, Ye L, Blank M, Goodman R. · 2003
Researchers exposed fruit flies to a discontinuous RF signal from a GSM multiband phone at 900/1,900 MHz with SAR approximately 1.4 W/kg for 10 days from egg laying through pupation. The non-thermal radiation increased offspring numbers, elevated hsp70 levels, increased SRE DNA-binding, and induced ELK-1 phosphorylation.
Liljestrand B, Sandström M, Hansson Mild K. · 2003
The study aimed to investigate RF exposure during use of electrosurgical units. Researchers measured electric fields near the lead wires of two electrosurgical units, a BARD 3000 at 0.5 MHz and an ERBE ICC 350 at 0.3–1 MHz, at distances of 5–30 cm during cutting and coagulating at 10–100 W. The calculated local exposure of the surgeon's hand was estimated to exceed 15 kV/m for the electric field and 16 µT for the magnetic field, exceeding the suggested international reference levels at 0.5 MHz of 610 V/m and 4 µT.
Huber R et al. · 2003
Desta AB, Owen RD, Cress LW. · 2003
Researchers exposed L929 murine fibroblast cells to radiofrequency radiation from a time division multiple access wireless phone operating at 835 MHz to determine the effect on ornithine decarboxylase activity. Exposure lasted 8 hours at average specific absorption rates ranging from less than 1 W/kg up to 15 W/kg, after which cells were harvested and ODC activity was measured. No statistically significant difference in ODC activity was found between exposed and sham-exposed cells at non-thermal specific absorption rates. At SARs that caused measurable heating, a dose-dependent decrease in enzymatic activity was observed and was consistent with a comparable decrease caused by non-RF-radiation heating.
Wilén J, Sandström M, Hansson Mild K · 2003
Researchers selected 2,402 people from an epidemiological study who used any of the four most common GSM MP. The study combined data on symptom prevalence, calling time per day, and number of calls per day with measurements of the Specific Absorption Rate (SAR). The results indicated that SAR values above 0.5 W/kg may be an important factor for the prevalence of some symptoms, especially in combination with long calling times per day.
Mashevich M et al. · 2003
Researchers examined whether in vitro exposure of human peripheral blood lymphocytes to continuous 830 MHz electromagnetic fields causes losses and gains of chromosomes, a condition called aneuploidy. Cells were irradiated at SAR levels ranging from 1.6 to 8.8 W/kg for 72 hours. A linear increase in chromosome 17 aneuploidy was observed as a function of the SAR value, which the researchers described as a genotoxic effect. Control experiments conducted without any RF radiation across a temperature range of 34.5 to 38.5 °C showed that elevated temperature was not associated with the increased aneuploidy or the changes in centromeric DNA replication seen after RF exposure.
Hietanen M, Hämäläinen A-M, Husman T. · 2002
The study tested the hypothesis that hypersensitive persons perceive symptoms from RF fields using double blind provocation experiments. Twenty volunteers who reported sensitivity to cellular phones participated. Exposure sources were one analogue NMT phone at 900 MHz and two digital GSM phones at 900 and 1800 MHz. Each test session lasted 30 minutes with three or four sessions in random order per day. More symptoms were reported during sham exposure than during real exposure, and no subject could distinguish real from sham exposure.
McNamee JP et al. · 2002
Blood cultures from human volunteers were exposed to an acute 1.9 GHz pulse-modulated radiofrequency (RF) field for 2 h using a series of six circularly polarized, cylindrical waveguides. Mean specific absorption rates (SARs) ranged from 0 to 10 W/kg and the temperature within the cultures during the exposure was maintained at 37.0 ± 0.5°C. DNA damage was quantified in leukocytes by the alkaline comet assay and the cytokinesis-block micronucleus assay. No evidence of increased primary DNA damage was detected by the comet assay and no significant differences in micronucleus frequency were found at any SAR tested.
McNamee JP et al. · 2002
Human blood cultures were exposed to a 1.9 GHz continuous-wave radiofrequency field for 2 hours at SARs of 0.0, 0.1, 0.26, 0.92, 2.4, and 10 W/kg while temperature was maintained at 37.0 ± 0.5°C. DNA damage was measured immediately after exposure using the alkaline comet assay with four parameters, and micronucleus formation was assessed using the cytokinesis-block micronucleus assay. No evidence of increased primary DNA damage was detected at any SAR tested. There was no significant difference in micronucleus incidence between exposed cultures and sham controls at any SAR.
Vangelova K, Israel M, Mihaylov S. · 2002
Researchers studied 12 male satellite station operators during 24-hour shifts and compared them with 12 unexposed controls. Exposure was low-level with specific absorption of 0.1127 J.kg-1. Exposed operators had significantly increased 24-hour excretion of 11-OCS and disrupted circadian rhythm, including increased mesor, decreased amplitude, and shifted acrophase. Catecholamine excretion rates also changed significantly with greater variability.
Thompson CJ, Anderson V, Rowley JT. · 2002
The broad objective was to assess radiofrequency exposure limits, hazard thresholds, and safety factors using probabilistic risk analysis. Analysis of SAR variables including conductivity and permittivity of grey brain matter and radiated field strengths supported the hypothesis that SAR values are lognormally distributed. The probability that SAR exceeds a threshold was derived and shown to be very low for handset SARs relative to allowable standard limits. The analysis focused on peak radiofrequency SAR values in the brain from digital mobile telephones operating at approximately 900 MHz.
Pacini S et al. · 2002
Researchers exposed human skin fibroblasts to GSM cellular phone radiofrequency for 1 hour. GSM exposure induced alterations in cell morphology and increased expression of mitogenic signal transduction genes, cell growth inhibitors, and apoptosis-related genes. A significant increase in DNA synthesis and intracellular mitogenic second messenger formation corresponded with high expression of MAP kinase family genes.
Higuchi Y et al. · 2002
Researchers performed a left-sided hemilaminectomy in adult Sprague-Dawley rats to expose the C6 dorsal root ganglion. Rats received pulsed radiofrequency, continuous radiofrequency, or sham treatment with the electrode on the ganglion for 120 seconds. Pulsed radiofrequency significantly increased cFOS-immunoreactive neurons in the superficial dorsal horn laminae three hours after treatment, while continuous radiofrequency did not. The authors concluded that pulsed radiofrequency activates pain-processing neurons in the dorsal horn without tissue heating.
Hanada E, Hoshino Y, Oyama H, Watanabe Y, Nose Y. · 2002
Researchers tested the effect of wireless LAN communication on medical electronic equipment and the effect of electronic equipment on wireless LAN communication. They observed nine pieces of electronic equipment in operating mode while transmitting radio waves from a wireless LAN. No equipment malfunction occurred even with the access point very close to the equipment surface during data transmission. Medical equipment caused little change in wireless communication effectiveness, but electric knives and a remote patient monitor reduced the reception rate to about 60%. Wireless LAN speed was temporarily reduced only when a microwave oven was close to and facing the access point.
Braune S, Riedel A, Schulte-Monting J, Raczek J. · 2002
The study investigated the hypothesis that exposure to EMFs can increase sympathetic vasoconstrictor activity. Forty healthy young males and females underwent a single-blind, placebo-controlled protocol on two different days with randomized EMF and placebo periods. The EMF exposure was a GSM-like signal at 900 MHz, pulsed with 217 Hz, 2 W, delivered by a mobile phone on the right side of the head. Blood pressure, heart rate, cutaneous capillary perfusion, and serum levels of norepinephrine, epinephrine, cortisol, and endothelin were measured. Systolic and diastolic blood pressure increased about 5 mmHg during the protocol, but the changes were independent of EMF exposure.
Tice RR, Hook GG, Donner M, McRee DI, Guy AW. · 2002
DNA damage in leukocytes was assessed with the alkaline comet assay and chromosomal damage in lymphocytes with the micronucleus assay. No significant increase in DNA damage was seen after 3 or 24 hours, and no increase in micronucleated lymphocytes occurred after 3 hours. However, 24-hour exposures at 5.0 or 10.0 W/kg significantly increased micronucleated lymphocytes about fourfold, regardless of signal type, modulation, or frequency.
Testylier G, Tonduli L, Malabiau R, Debouzy JC · 2002
Rats were exposed to 2.45 GHz continuous wave at 2 or 4 mW/cm(2) for 1 h during the day, or to 800 MHz modulated at 32 Hz at 200 mW/cm(2) for 1 or 14 h during the night. Exposure at 4 mW/cm(2) caused a significant 40% decrease in mean acetylcholine release from hippocampus, maximal at 5 h post exposure. Fourteen-hour nighttime exposure at 800 MHz induced a significant 43% decrease in acetylcholine release during 11 p.m.-4 a.m. compared to control rats.
