Keshvari J, Lang S. · 2005
Researchers used the finite-difference time-domain (FDTD) computational method to calculate specific absorption rate (SAR) in anatomically correct adult and child head models exposed to a half-wave dipole at 900, 1800, and 2450 MHz. The ear and eye regions were studied because they represent realistic exposure scenarios for mobile wireless communication devices.
Cosquer B, Galani R, Kuster N, Cassel JC. · 2005
In a first phase, researchers validated the elevated plus-maze apparatus in male Sprague-Dawley rats. They tested anxiety responses at light intensities of 200, 30, 10, and 2.5 lux and with diazepam doses of 0.5 and 1.0 mg/kg. Anxiety responses decreased with decreasing light intensity and were attenuated by diazepam. A separate group of rats was then exposed to 2.45 GHz EMFs with a whole-body SAR of 0.6 W/kg and brain-averaged SAR of 0.9 W/kg for 45 min. EMF exposure did not significantly affect anxiety responses at either low or high ambient light intensity.
Lai H, Singh NP · 2005
Researchers studied four groups of rats: one exposed to 2450-MHz microwaves at 1 mW/cm2, one to magnetic field noise at 45 mG, one to both simultaneously, and a sham-exposed group. Brain cells of microwave-exposed rats had significantly higher levels of DNA single- and double-strand breaks compared with sham-exposed animals. Noise exposure alone did not significantly affect DNA strand break levels, but simultaneous noise exposure blocked the microwave-induced increases.
Lai H, Singh NP · 2005
Researchers exposed rats to cell phone-frequency microwaves (2450 MHz) for 2 hours and found significant DNA damage in brain cells. However, when they simultaneously exposed the rats to a weak magnetic field with random fluctuations, it completely blocked the DNA damage from occurring. This suggests that certain types of magnetic field exposure might actually protect against some forms of EMF damage.
Komatsubara Y et al. · 2005
Researchers exposed murine m5S cells to 2.45 GHz high-frequency electromagnetic fields for 2 hours at SARs of 5, 10, 20, 50, and 100 W/kg continuous wave and at a mean SAR of 100 W/kg pulse wave with a maximum of 900 W/kg. The effects were compared with sham-exposed controls and with mitomycin C and X-ray treatments as positive controls. No significant differences in chromosomal aberrations were observed between HFEMF-exposed cells and sham controls, while positive controls increased chromatid-type and chromosome-type aberrations.
Cosquer B, Vasconcelos AP, Frohlich J, Cassel JC. · 2005
Wang J et al. · 2005
Researchers exposed mouse C3H10T1/2 cells to 2450 MHz HFEMF at SARs of 5 to 200 W/kg for 2 hours, with or without methylcholanthrene (MC) and the tumor promoter TPA. Transformed foci of Type II and Type III were counted as the endpoint. No significant differences were observed in malignant transformation frequency between controls and HFEMF with or without TPA. Transformation frequency increased for HFEMF at SAR above 100 W/kg when combined with MC or MC plus TPA, while heat exposure did not increase transformation.
Trosic I, Busljeta I. · 2005
Researchers exposed Wistar rats to 2.45 GHz continuous RF/MW radiation for 2 hours daily, 7 days a week, at 5–10 mW/cm², with subgroups receiving 4, 16, 30, and 60 total hours of exposure. The frequency of micronucleated bone marrow erythrocytes was significantly increased after 15 irradiation treatments. No statistically significant differences in micronucleus frequency were observed after 2, 8, or 30 irradiation treatments.
Cobb BL, Jauchem JR, Adair ER. · 2004
Researchers exposed rats to 2450 MHz fields at 0.6 W/kg for 45 minutes daily over 10 days in circularly polarized waveguides and gave them a pre-exposure injection of a psychoactive compound or saline. Error rate analysis showed no significant effect of microwave exposure, no drug effect, and no exposure-drug interaction, while performance improved across test days indicating learning. Time to criterion showed no significant exposure effect but a significant drug effect, a significant test day effect, and a significant drug-by-test-day interaction. The authors concluded there is no evidence that microwave radiation exposure under the tested parameters caused decrements in spatial memory learning.
Lagroye I et al. · 2004
The study aimed to investigate the effect of 2450 MHz pulsed-wave microwaves on DNA damage in rat brain cells and whether proteinase K is needed to detect such damage. Rats exposed to γ-rays showed significant DNA damage using both comet assay versions independent of proteinase K. Neither assay version detected any difference in comet length or normalized comet moment between sham-exposed and microwave-exposed rats regardless of proteinase K inclusion. No DNA damage was detected in brain cells after exposure to 2450 MHz pulsed-wave microwaves at 1.2 W kg−1 regardless of proteinase K inclusion. The results support the conclusion that low-level 2450 MHz pulsed-wave microwave exposures do not induce DNA damage detectable by the alkaline comet assay.
Koyama S, Isozumi Y, Suzuki Y, Taki M, Miyakoshi J. · 2004
Researchers exposed Chinese hamster ovary CHO-K1 cells to 2.45-GHz electromagnetic fields for 2 hours at SARs of 5, 10, 20, 50, 100, and 200 W/kg to study micronucleus formation. Micronucleus frequency in cells exposed at SARs lower than 50 W/kg did not differ from sham-exposed controls. At SARs of 100 and 200 W/kg, micronucleus frequency was significantly higher than in sham-exposed controls. The researchers also found that micronucleus frequency increased in a temperature-dependent manner when cells were heat-treated at temperatures from 38 to 42 degrees C.
Koyama S, Isozumi Y, Suzuki Y, Taki M, Miyakoshi J · 2004
Japanese researchers exposed Chinese hamster cells to 2.45 GHz radiation (the same frequency as microwave ovens and WiFi) for 2 hours at various power levels. They found that high-intensity exposures (100-200 W/kg) caused significant chromosome damage, while lower levels showed no effect. The damage appeared to be caused by heating rather than the radiation itself.
Sandrini L et al. · 2004
Researchers created a female dielectric anatomical model and compared power absorption in male and female models from 0.1 to 4 GHz. Whole-body-averaged SAR was higher in the female model, mainly due to a thicker subcutaneous fat layer. Maximum 1 g and 10 g averaged SAR did not depend on gender because it occurs in regions without subcutaneous fat.
Yao K, Wang KJ, Sun ZH, Tan J, Xu W, Zhu LJ, Lu de Q. · 2004
Researchers exposed cultured rabbit lens epithelial cells to continuous 2,450 MHz microwave radiation at power densities of 0.10, 0.25, 0.50, 1.00, and 2.00 mW/cm2 for 8 hours. P27Kip1 protein expression increased markedly but its mRNA levels did not change, and P21WAF1 protein and mRNA levels showed no detectable differences between exposed and control groups.
Kim MJ, Rhee SJ. · 2004
Researchers exposed rats to 2.45 GHz microwave radiation for 15 minutes and then fed them diets containing 0%, 0.25%, or 0.5% catechin. Microwave exposure increased cytochrome P450 levels by 85% and NADPH-cytochrome P450 reductase activity by 29% compared with normal rats. It also raised superoxide radical concentrations by 35% and decreased superoxide dismutase activity by 34% and glutathione peroxidase activity by 28%. Catechin supplementation at 0.25% and 0.5% lowered superoxide radicals by 11% and 12%, increased superoxide dismutase activity by 19% and 25%, and kept glutathione peroxidase near normal.
Kojima M et al. · 2004
Researchers exposed one eye each of 43 male pigmented rabbits to microwaves at 300 mW/cm2, either under systemic anesthesia or without anesthesia. Exposed eyes showed miosis, conjunctival congestion, corneal edema, and increased light scattering in the lens, and all of these anterior ocular changes disappeared within a week. Rabbits under systemic anesthesia showed much stronger symptoms, and their ocular temperatures were 2-9 degrees C higher than those without anesthesia.
Busljeta I, Trosic I, Milkovic-Kraus S. · 2004
Researchers exposed rats to 2.45 GHz radiation (WiFi frequency) for 2 hours daily and found it disrupted blood cell production in bone marrow while increasing genetic damage markers. These effects occurred at non-heating power levels, suggesting biological impacts below thermal thresholds.
Trosic I, Busljeta I, Pavicic I. · 2004
Researchers investigated the effect of 2.45 GHz microwave irradiation on blood-forming cells in rats. Rats were exposed to a field power density of 5-10 mW/cm2 and a whole-body average SAR of 1-2 W/kg for 2 hours a day, 7 days a week, for 2, 8, 15, or 30 days. A significant decrease in lymphoblast count was observed at 15 and 30 days, while other examined parameters did not differ significantly from sham-exposed controls.
Ramundo-Orlando A, Liberti M, Mossa G, D'Inzeo G. · 2004
Enzyme activity decreased only at 5.6 W/kg, with no response at lower SAR values. When using deglycated ascorbate oxidase without oligosaccharide chains, microwave irradiation caused no enzyme activity changes, indicating the chains are necessary for the effect. Catalytic properties of both enzyme forms were unaffected by microwave exposure in solution or in liposomes, ruling out enzyme conformational changes as a mechanism. The authors concluded that oligosaccharide chains of ascorbate oxidase are critical for microwave effects on lipid membranes.
Busljeta I, Trosic I, Milkovic-Kraus S. · 2004
The study observed erythropoietic changes in rats subchronically exposed to radiofrequency microwave radiation at a nonthermal level. Adult male Wistar rats were exposed to 2.45 GHz continuous RF/MW fields for 2 hours daily, 7 days a week, at 5 – 10 mW/cm2. In exposed animals, erythrocyte count, haemoglobin and haematocrit were increased in peripheral blood on irradiation days 8 and 15. Anuclear cells and erythropoietic precursor cells were significantly decreased in the bone marrow on day 15, while micronucleated cells' frequency was increased.
Trosic I, Busljeta I, Modlic B. · 2004
Researchers used an erythrocyte micronucleus assay to investigate genetic damage in bone marrow red cells of rats exposed to radiofrequency/microwave radiation. Wistar rats were exposed to a 2.45 GHz continuous field for 2 hours daily, 7 days a week, at a power density of 5–10 mW/cm2, with a whole body average specific absorption rate calculated to be 1.25 ± 0.36 W/kg. Significant differences in polychromatic erythrocytes were found on experimental days 8 and 15, and the frequency of micronucleated polychromatic erythrocytes was also significantly increased on day 15. Comparisons after 2, 8, and 30 irradiation treatments did not reveal statistically significant differences between sham-exposed and treated subgroups.
Cassel JC, Cosquer B, Galani R, Kuster N. · 2004
Rats were tested in a 12-arm radial-maze after daily exposure to 2.45 GHz microwaves for 45 minutes at a SAR of 0.6 W/kg. The performance of exposed rats was comparable to that found in sham-exposed or in naive rats.
Lagroye I et al. · 2004
Researchers exposed C3H 10T½ cells to 2450 MHz CW microwaves at 1.9 W/kg for 2 hours, then irradiated them with 4 Gy gamma rays, and used the single-cell gel electrophoresis assay to detect DNA damage. Ionizing radiation induced significant DNA damage, but microwave exposure alone caused no detectable DNA damage. Microwaves did not impede DNA migration induced by gamma rays, and no evidence of DNA–protein crosslinks or changes in DNA-associated protein was found after microwave exposure.
Ono T et al. · 2004
A possible mutagenic effect of 2.45 GHz radiofrequency exposure was examined using lacZ-transgenic MutaTM mice. Offspring were exposed in utero for 16 hours a day from embryonic day 0 to 15 and examined at 10 weeks of age. Mutation frequencies at the lacZ gene in spleen, liver, brain, and testis were similar to those in non-exposed mice. Sequencing of mutant DNAs showed no appreciable difference in mutation quality between exposed and non-exposed samples.
Monfrecola G, Moffa G, Procaccini EM. · 2003
The study assessed the effects of non-ionizing electromagnetic radiation emitted by CFs on cutaneous blood flow in 30 healthy volunteers aged 18 to 53 years. Cutaneous blood flow was measured on the ear skin with a laser Doppler He-Ne flowmeter under controlled temperature and humidity. Microflow was recorded across phases T0 through T6, including no CF contact, CF off touching the ear, CF on, CF on and receiving, then back through CF on, CF off, and no contact. During phases T1 to T5 microflow increased by 61.38% to 157.67% relative to baseline, and all these phases showed statistically significant elevations compared with baseline.
