Unknown authors · 2001
Australian researchers tested 30 volunteers exposed to 28 microT 50 Hz magnetic fields (similar to occupational levels) for 50 minutes while performing cognitive tests. The study found significant impairment in short-term memory for word recall and decreased performance on executive functioning tasks requiring working memory. These findings suggest power frequency magnetic fields may affect specific brain functions related to learning and mental processing.
Cranfield CG, Wood AW, Anderson V, Menezes KG. · 2001
Researchers tested whether simulated GSM mobile phone signals at 915 MHz and 2 W kg(-1) influence calcium concentration or calcium signalling patterns in a human lymphocyte cell line. No significant changes were found in the regression slope of calcium fluorescence, mean calcium concentration, number of calcium spikes, or mean height of those spikes. A significant alteration in average frequency from Fourier spectra was found in one category only: pulsed wave exposure of activated cells.
Unknown authors · 2001
The study examined the effect of a sinusoidal 50 Hz magnetic field on preimplantation CBA/S mouse embryos in vitro. Embryos were exposed to a field of 10 A/m rms corresponding to 13 microT rms while cultured at 37°C in a CO2 incubator. Vitality and developmental stages were similar between groups, though slightly more dead embryos appeared on day 1 in the exposed group (P<0.05) and development was slightly impaired. The authors concluded that the exposure did not significantly disturb development up to the blastocyst stage.
Hanada E, Kodama K, Takano K, Watanabe Y, Nose Y. · 2001
Researchers measured electric field intensity from radio waves entering an 11-floor hospital that was under construction. The highest level recorded was about 200 V/m at 2.79 GHz, coming from airport surveillance radar. The maximum intensity from cellular phone base stations was 1.78 V/m. The researchers concluded that each hospital in urban areas should measure its own electromagnetic environment to help prevent interference with electronic medical equipment.
Trosic I. · 2001
Researchers exposed rats to microwave radiation at 2450 MHz (the same frequency used in microwave ovens and some WiFi devices) and examined lung cells. They found that exposure caused immune cells in the lungs to fuse together into abnormal giant cells with multiple nuclei - a sign of chronic lung inflammation. The effect became stronger with more radiation treatments, suggesting cumulative damage to the respiratory system.
Novoselova EG, Ogai VB, Sorokina OV, Novikov VV, Fesenko EE · 2001
Researchers studied the effect of fractionated low-intensity microwave exposure and a combined weak magnetic field on tumor necrosis factor production in macrophages of mice with experimental solid tumors. Exposure to both microwaves and magnetic field enhanced the adaptive response, with higher tumor necrosis factor production in peritoneal macrophages of exposed tumor-bearing mice compared to unexposed mice.
Palfia Z, Somosy Z, Rez G · 2001
Researchers evaluated murine jejunal epithelial tight junctions after whole-body X-ray and microwave exposure using freeze fracture replicas. X-ray treatment at 4 Gy caused partial dearrangement of the ZO strand network that only partially regenerated by 24 hours. Microwave treatment at 16 Hz-modulated 2.45 GHz and 1 mW/cm2 for 1 hour did not cause dearrangement but increased integration of the tight junctional structure. The microwave effect agreed with an increase in cytochemically detectable ZO-bound calcium.
Radicheva N, Mileva K, Georgieva B, Kristev I · 2001
Researchers exposed isolated frog muscle fibers to continuous 2.45 GHz microwave radiation at 20 mW/cm² for one hour. Repetitive stimulation at 200 ms intervals evoked intracellular action potentials and twitch contractions. The twitch amplitude curve showed a drastic fall in the first 5 seconds followed by an increase and then a decrease. After microwave exposure, the changes in amplitude and time parameters that characterize fatigue were attenuated and delayed compared to controls. The authors concluded that microwaves have a specific non-thermal influence causing some resistance to fatigue.
Yang R, Chen J, Deng Z, Liu X, · 2001
Researchers cultured pig retinal ganglion cells in vitro, added vitamin E at different concentrations, and exposed them to 2450 MHz microwave radiation at 30 mW/cm² for 1 hour. Microwave exposure caused cell congregation, axon disappearance, mitochondria and endoplasmic reticulum swelling, and apoptosis. Vitamin E groups showed no obvious changes under optical microscope, though electron microscopy revealed light mitochondria swelling with intact cristae. The researchers concluded that microwave induced morphological damage and vitamin E reduced this damage to some extent.
Unknown authors · 2001
Researchers evaluated leukemia mortality among adults and childhood leukemia incidence in a 10 km area around the Vatican Radio Station in Rome. The station transmitted up to 600 kW and electric field measurements near it ranged from 1.5 to 25 V/m. Childhood leukemia incidence was higher than expected within 6 km (SIR = 217; 95% CI 99-405), and Stone's test showed a significant decrease in risk with distance for male adult mortality (p = 0.03) and childhood incidence (p = 0.04).
Pashovkina MS, Akoev IG · 2001
Researchers exposed samples to pulse-modulated electromagnetic radiation at 2375 MHz with intensities of 0.8, 8.0, and 40.0 microW/cm2, modulation range 30-310 Hz, for 1-3 minutes. They observed a change in alkaline phosphotase activity in vitro.
Pashovkina MS, Akoev IG · 2001
Researchers exposed donor blood to pulse-modulated microwaves at 2375 MHz with intensities of 2 microW/cm2 and 8 microW/cm2, pulse modulation from 50 to 390 Hz, for 5 minutes. Aspartate aminotransferase activity was strongly dependent on both modulation frequency and microwave intensity. Maximum activity was found at 390 Hz and 8 microW/cm2, reaching about six times the control level.
Alhekail ZO. · 2001
Researchers surveyed microwave ovens used in households and restaurants in Riyadh city, Saudi Arabia. One oven leaked more than the 5 mW cm-2 limit, and fifteen others leaked 1 mW cm-2 or more, with the rest leaking less. The researchers concluded that a detrimental effect on health is an unlikely result of exposure to radiation from microwave ovens.
Geller L, Thuroczy G, Merkely B. · 2001
Researchers examined electromagnetic compatibility of cellular phones and pacemakers in four phone systems and fifteen pacemaker types, both in vitro and in vivo in humans. They performed more than 1100 in-vitro and 130 in-vivo tests. No electromagnetic compatibility disturbance was observed with GSM and DCS 1800 MHz phones, while the highest problem rate occurred with NMT 450 MHz phones at 10.5% to 63%.
Trosic I · 2001
Researchers exposed rats to 2450 MHz microwaves at power densities of 5 to 15 mW/cm², in sessions of two hours each, with groups receiving 2, 8, 13, or 22 treatments. Multinucleated cells significantly increased (p<0.01) in treated animals, with the elevation being time- and dose-dependent. Cell viability did not significantly change in the irradiated animal group compared with the control group.
Fernie KJ, Bird DM. · 2001
Researchers investigated whether exposure to magnetic and electric fields similar to those from power lines induces an immune response and alters oxidative stress levels in American kestrels. Captive male kestrels were bred under control or EMF conditions equivalent to those experienced by wild kestrels. Short-term EMF exposure suppressed plasma total proteins, hematocrits, and carotenoids in the first half of the breeding season, and also suppressed erythrocyte cells and lymphocyte proportions while elevating granulosa proportions at the end of the breeding season. Long-term EMF exposure may be linked to higher levels of oxidative stress through EMF exposure only, and also suppressed hematocrits in the first half of the reproductive period.
Jajte J, Zmyślony M, Palus J, Dziubałtowska E, Rajkowska E. · 2001
Researchers used the alkaline comet assay to assess DNA damage in rat peripheral blood lymphocytes exposed in vitro to iron ions and a 50 Hz magnetic field. Cell samples were incubated for 3 hours in Helmholtz coils at 7 mT 50 Hz, and some were treated with ferrous chloride at 10 μg/ml during that exposure. A significant increase in cells with DNA damage was found only after simultaneous exposure to ferrous chloride and the 7 mT 50 Hz magnetic field, compared to control samples or those incubated with ferrous chloride alone. When cells were treated with melatonin before that combined exposure, the number of damaged cells was significantly reduced, with the reduction reaching about 50% at 0.5 mM and about 100% at 1.0 mM.
Simkó M, Droste S, Kriehuber R, Weiss DG · 2001
Researchers examined the effects of 50 Hz electromagnetic fields on phagocytosis and free radical production in mouse bone marrow-derived macrophages exposed in vitro to magnetic field densities of 0.5 to 1.5 mT. Short-time exposure of 45 minutes resulted in a significantly increased phagocytic uptake of 36.3% plus or minus 15.1%, as measured by the internalization rate of latex beads. A significant increase in superoxide production was also detected after exposure to electromagnetic fields. Because co-exposure to electromagnetic fields and TPA showed no additive increase in bead uptake, researchers concluded that the electromagnetic fields-induced stimulation does not involve the protein kinase C signal transduction pathway.
Zook BC, Simmens SJ, · 2001
Researchers exposed Sprague-Dawley rats to 860 MHz pulsed or continuous radiofrequency radiation for 6 hours per day, 5 days per week from 2 up to 24 months of age. The specific absorption rate was 1.0 W/ kg averaged over the brain. The rats were offspring of females injected intravenously with 0, 2.5, or 10 mg/kg ethylnitrosourea to induce brain tumors. There was no statistically significant evidence that the radiation induced neoplasia in any tissues or promoted cranial or spinal nerve or spinal cord tumors. The radiation had no statistically significant effect on brain tumor number, volume, location, multiplicity, histological type, malignancy, or fatality.
Unknown authors · 2000
Researchers conducted a pooled analysis based on individual records from nine studies. The analysis included 3203 children with leukaemia and 10 338 control children with estimated residential magnetic field exposures levels < 0.4 μT, and 44 children with leukaemia and 62 control children with exposures ≥ 0.4 μT. For exposures ≥ 0.4 μT the estimated summary relative risk was 2.00 (1.27–3.13), P value = 0.002, while for exposures < 0.4 μT risk estimates were near the no effect level. Adjustment for potential confounding variables did not appreciably change the results. No evidence was found for a wire-code paradox; the highest wire code category showed a relative risk of 1.24 (0.82–1.87).
Huber R et al. · 2000
Researchers exposed healthy young male subjects for 30 minutes to EMF at 900 MHz and a spatial peak specific absorption rate of 1 W/kg during the waking period before sleep. Compared with a sham exposure control condition, EEG spectral power during non-rapid eye movement sleep was increased, with the maximum rise in the 9.75-11.25 Hz and 12.5-13.25 Hz bands during the initial part of sleep. The researchers concluded that the changes of brain function induced by pulsed high-frequency EMF outlast the exposure period.
Koivisto et al. · 2000
The study examined possible influences of a 902 MHz electromagnetic field emitted by cellular telephones on cognitive functioning in 48 healthy humans. A battery of 12 reaction time tasks was performed twice by each participant in a counterbalanced order, once with and once without exposure to the field. Exposure speeded up response times in simple reaction time and vigilance tasks and decreased the cognitive time needed in a mental arithmetic task. The results suggest that exposure may have a facilitatory effect on brain functioning, especially in tasks requiring attention and manipulation of information in working memory.
Krause CM et al. · 2000
Researchers studied the effects of cellular phone EMF on EEG frequency bands in 16 normal subjects performing an auditory memory task. All subjects completed the memory task with and without exposure to a digital 902 MHz EMF in counterbalanced order. EMF exposure significantly increased EEG power in the 8-10 Hz frequency band only. EMF presence altered ERD/ERS responses across all studied frequency bands depending on time and memory task phase.
Unknown authors · 2000
This 2000 case-control study examined 469 brain cancer patients and 422 matched controls across five U.S. medical centers to investigate whether handheld cell phone use increases brain cancer risk. Researchers found no overall increased risk, with users actually showing slightly lower odds ratios compared to non-users, though they noted more brain tumors occurred on the same side of the head where phones were used. The study acknowledged important limitations including short average use duration (under 3 years) and the need for longer-term data to assess slow-growing tumors.
Krause CM et al. · 2000
Researchers examined the effects of electromagnetic fields from cellular phones on event-related desynchronization and synchronization responses in four EEG frequency bands during cognitive processing. Twenty-four subjects performed a visual sequential letter task with three working memory load conditions both with and without exposure to a digital 902 MHz EMF in counterbalanced order. The presence of EMF altered the ERD/ERS responses in the 6-8 and 8-10 Hz frequency bands but only when examined as a function of memory load and depending on whether the stimulus was a target.
