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.
Papageorgiou CC et al. · 2004
Ten women and nine men performed a short memory task during baseline and during exposure to a 900 MHz signal. Baseline EEG energy was higher in men than in women, and EMF exposure decreased EEG energy in men but increased it in women. Memory performance did not change with EMF exposure or gender.
Aran JM et al. · 2004
In the first experiment, guinea pigs were exposed to GSM microwaves at SARs of 1, 2, and 4 W/kg for 1 hour per day, 5 days per week, for 2 months. In the second experiment, guinea pigs were exposed at 4 W/kg and auditory brainstem response thresholds were monitored. Repeated-measures ANOVA showed no difference in DPOAE amplitudes or ABR thresholds between exposed and sham-exposed groups. Acute exposure for 1 hour also produced no statistically significant change in ABR thresholds. In vitro, organs of Corti from newborn rats exposed to 1 W/kg for 24-48 hours appeared normal under light microscopy after 2-3 days of culture.
Anderson, L. · 2004
Researchers conducted a two-year chronic bioassay to determine whether long-term exposure to a 1.6 GHz radiofrequency field would affect cancer incidence in Fischer 344 rats. Timed-pregnant rats were assigned to far-field RF Iridium or sham groups, with whole-body exposures starting at 19 days gestation for 2 hours per day, 7 days per week until weaning. Offspring then received near-field head-first exposures 2 hours per day, 5 days per week from 36 days old until 2 years of age at brain SAR levels of 1.6 W/kg, 0.16 W/kg, or sham. No statistically significant differences were seen among groups for live pups per litter, survival index, weaning weights, clinical signs, or neoplastic lesions, and male survival was similar across groups while female cage controls had reduced survival time.
Unknown authors · 2004
Case reports of peripheral neurological effects of radiofrequency radiation describe mainly disturbances of noxious sensation called dysaesthesia. Cases have arisen after exposure to much of the frequency range from low MHz to GHz. After very high intensity exposures nerves may be grossly injured; however, after lower intensity exposures which may result in dysaesthesia, ordinary nerve conduction studies demonstrate no abnormality although current perception threshold studies may. Only a small proportion of similarly exposed persons develop symptoms. Some observations are not consistent with the hypothesis that all health effects of radiofrequency radiation arise from thermal mechanisms.
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.
Hinrichs H, Heinze HJ. · 2004
Researchers investigated potential effects of GSM 1800 electromagnetic fields on verbal memory encoding by recording event-related magnetic fields from the brain during subsequent memory retrieval. Twelve normal subjects each completed two experimental sessions, one with EMF exposure during the study phase and one without. Exposure to EMF changed an early (350-400 ms) task-specific component of the event-related magnetic field, indicating interference with item encoding. Behavioral measures were not significantly affected.
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.
Munoz S, Sebastian JL, Sancho M, Miranda JM · 2004
Researchers calculated the transmembrane voltage induced on erythrocyte, codocyte, ovalocyte, and spherocyte cell models exposed to a linearly polarized electromagnetic plane wave at 1800 MHz. The induced voltage on the original erythrocyte shape was higher than on the altered cell geometries. Erythrocyte shape and membrane electric permittivity were found to play a fundamental role in the induced transmembrane voltage values. A finite element numerical technique with adaptive meshing was used for the calculations.
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.
Sarimov R et al. · 2004
Researchers exposed lymphocytes from seven healthy persons to GSM microwaves at different frequencies in the range of 895-915 MHz and measured changes in chromatin conformation. A 30-min exposure at 900 and 905 MHz produced statistically significant condensation of chromatin in lymphocytes from 1 of 3 tested donors. Stronger effects were found following 1-h exposure, with chromatin condensation in 3 donors and decondensation in 1 donor. The observed chromatin changes were similar to effects of heat shock within the temperature window of 40/spl deg/C-44/spl deg/C.
Anderson LE et al. · 2004
Researchers set out to determine whether long-term exposure to a 1.6 GHz radiofrequency field would affect cancer incidence in Fischer 344 rats. Offspring were exposed to near-field radiofrequency signals at brain SAR levels of 1.6 W/kg or 0.16 W/kg for 2 hours per day, 5 days per week, from about 36 days old until they were 2 years old. No statistically significant differences were found among treatment groups for neoplastic lesions or other clinical signs.
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.
Sarimov et al. · 2004
Researchers exposed human white blood cells (lymphocytes) to cell phone radiation at levels similar to what phones emit during calls. They found that 30-60 minutes of exposure caused changes in the DNA packaging inside cells that were similar to heat stress damage. These cellular changes occurred in most test subjects and suggest that phone radiation may trigger stress responses in our immune cells even at low power levels.
Sarimov et al. · 2004
Researchers exposed human immune cells to cell phone radiation at typical frequencies for 30 minutes to 1 hour. The extremely weak signals - 200 times below safety limits - triggered DNA packaging changes resembling heat stress in most subjects, suggesting cellular effects from everyday phone use.
Ilhan A et al. · 2004
Researchers investigated the effect of Ginkgo biloba on mobile phone-induced oxidative damage in rat brain tissue. Mobile phone exposure increased malondialdehyde, nitric oxide, xanthine oxidase, and adenosine deaminase while decreasing superoxide dismutase and glutathione peroxidase activities in brain tissue. Ginkgo biloba treatment prevented these oxidative alterations and the mobile phone-induced cellular injury in brain tissue.
Demsia G, Vlastos D, Matthopoulos DP. · 2004
The study aimed to investigate whether 910-MHz electromagnetic fields could be a noxious agent capable of inducing genotoxicity, and rats were exposed daily for 2 h over 30 consecutive days. Researchers examined bone marrow smears from EMF-exposed and sham-exposed animals and observed an almost threefold increase in micronuclei in polychromatic erythrocytes. An induction of micronuclei was also observed in polymorphonuclear cells.
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.
