Sykes PJ, McCallum BD, Bangay MJ, Hooker AM, Morley AA. · 2001
Researchers studied the effect of pulsed 900 MHz radiofrequency radiation at 4 W/kg on somatic intrachromosomal recombination in the spleen of pKZ1 mice. Mice were exposed daily for 30 minutes to 900 MHz fields for 1, 5, or 25 days, and spleen sections were screened for DNA inversion events three days after the last exposure. There was no significant difference between control and treated groups in the 1- and 5-day exposure groups, but a significant reduction in inversions was found in the 25-day group.
Maes A, Collier M, Verschaeve L · 2000
Researchers exposed human lymphocytes to 455.7 MHz microwaves from a car phone at a specific absorption rate of approximately 6.5 W/kg. No statistically significant difference was found between microwave-exposed and unexposed control samples for chromosome aberration or sister chromatid exchange frequency. When microwave exposure was followed by MMC treatment, some differences appeared between combined and MMC-only treatments, but results were inconsistent. Combined exposure with X-rays showed no indication of synergistic action between RF fields and X-rays. The authors concluded that the data do not support the hypothesis that RF fields act synergistically with chemical or physical mutagens.
Lu ST et al. · 2000
Researchers studied retinal effects of 1.25 GHz high peak power microwaves in Rhesus monkeys. Preexposure and postexposure fundus pictures and angiograms were all within normal limits. Cone photoreceptor response to light flash was enhanced at 8.4 and 20.2 W/kg R-SAR but not at 4.3 W/kg R-SAR. Enhanced glycogen storage in photoreceptors was observed in sham, 8.4, and 20.2 W/kg groups but not in the 4.3 W/kg group. No degenerative changes or ERG depression were observed, and retinal injury was considered very unlikely at 4 W/kg.
Vijayalaxmi, Leal BZ, Szilagyi M, Prihoda TJ, Meltz ML · 2000
Human peripheral blood samples from three volunteers were exposed to pulsed-wave 2450 MHz radiofrequency radiation for 2 hours. The exposure used a net forward power of 21 W with an average power density of 5 mW/cm2 and a mean specific absorption rate of 2.135 W/kg. DNA damage was measured using the alkaline comet assay immediately and 4 hours after exposure. No significant differences were found in comet tail length, fluorescence intensity, or tail moment between RF-exposed and sham-exposed lymphocytes at either time point. The response of lymphocytes exposed to ionizing radiation was significantly different from RF-radiation- and sham-exposed cells.
Schirmacher A et al. · 2000
Mezhevikina LM, Khramov RN, Lepikhov KA · 2000
Researchers cultured two-cell mouse embryos in vitro and exposed them to electromagnetic irradiation in the millimeter range. After 30 min of exposure, the embryos acquired the ability to develop on their own and could reach the stage of blastocyst in 150 microliters of Whitten cultural medium without serum or growth factors. The authors proposed that millimeter range electromagnetic waves activate metabolic processes and specifically the synthesis of factors controlling early embryonic development in culture.
Kalns J, Ryan KL, Mason PA, Bruno JG, Gooden R, Kiel JL. · 2000
Chiabrera A, Bianco B, Moggia E, Kaufman JJ, · 2000
The aim of the study was to observe Zeeman-Stark modeling of the RF EMF interaction with ligand binding. The model accounts for ion collision losses, endogenous forces, metabolic non-equilibrium, and thermal noise. The model predicts that ligand binding probability may be affected by low-intensity exogenous EMF when the receptor's potential energy well matches the radiofrequency photon energy. The authors state that the results point toward electromagnetic control of biochemical processes and the need for a new database of safety standards.
Romano-Spica V, Mucci N, Ursini CL, Ianni A, Bhat NK · 2000
Researchers analyzed gene expression in hemopoietic and testicular cell types after exposure to 50 MHz radiofrequency radiation modulated at 16 Hz. They observed overexpression of ets1 mRNA in Jurkat T-lymphoblastoid and Leydig TM3 cell lines only when the 16 Hz modulation was present. A putative candidate gene was also repressed after EMF exposure.
Peinnequin A et al. · 2000
Olchowik G, Maj JG · 2000
Researchers investigated the influence of microwave irradiation on gamma-glutamyl transpeptidase activity induced by hydrocortisone in rat liver. Rats received hydrocortisone at 20 mg/kg for 60 days and were exposed to microwave radiation at 53.57 GHz with power densities of 10 mW/cm2 and 1 mW/cm2 during and after treatment. The results indicate that microwave radiation may block the hydrocortisone-induced effect on GGT activity, and this blocking effect depends on the power density of the millimetre microwaves.
Zotti-Martelli L, Peccatori M, Scarpato R, Migliore L · 2000
Researchers exposed human peripheral blood lymphocytes in vitro to electromagnetic fields at two frequencies, 2.45 and 7.7 GHz, at power densities of 10, 20, and 30 mW/cm2 for 15, 30, and 60 minutes. At a power density of 30 mW/cm2 and after exposures of 30 and 60 minutes, both frequencies led to an induction of micronuclei compared to control cultures. The researchers concluded that microwaves are able to cause cytogenetic damage in human lymphocytes mainly for both high power density and long exposure time.
Linz et al. · 1999
Researchers tested the effects of radio frequency fields at 180, 900, and 1800 MHz on the electrical properties of isolated ventricular myocytes from guinea pigs and rats. The fields were applied using rectangular waveguides or a TEM cell at specific absorption rates up to 880 mW/kg, with 900 and 1800 MHz signals pulsed to the GSM standard. None of the tested electrophysiological parameters, including membrane potential, action potential, L-type calcium current, and potassium currents, were significantly changed by RF exposure. Lowering the temperature from 36°C to 24°C reduced current amplitude by almost 50% and shifted voltage dependence by about 5 mV, but RF exposure at the lower temperature still did not affect L-type calcium current.
Goswami PC et al. · 1999
Researchers exposed C3H 10T 1/2 mouse embryo fibroblasts to 835.62 MHz FMCW or 847.74 MHz CDMA microwaves at an average SAR of 0.6 W/kg and measured proto-oncogene expression. The exposures did not alter proto-oncogene expression kinetics after serum stimulation, nor did they change Jun and Myc mRNA levels or AP1, AP2, and NF-kappaB DNA-binding activity during the transition to plateau phase. However, 835.62 MHz FMCW exposure increased Fos mRNA about 2-fold in exponential and plateau-phase cells, and 847.74 MHz CDMA exposure increased it 1.4-fold.
Velizarov, S, Raskmark, P, Kwee, S, · 1999
Researchers exposed cell cultures to a GSM 960 MHz field in a TEM cell at 39°C and 35°C. Exposed cells showed a significant change in proliferation compared to non-exposed controls at both temperatures. Sham-exposed cells showed no significant change in proliferation at either temperature.
Morrissey JJ et al. · 1999
Researchers investigated the effects of a one-hour exposure of mice to a 1.6-GHz radiofrequency signal, either continuous wave or pulse-modulated at 11 Hz (IRIDIUM), on c-fos gene expression in the brain. C-fos expression was not significantly elevated until exposure levels exceeded six times the peak dose and 30 times the whole-body average dose relative to human cellular telephone exposure limits. The pattern of c-fos elevation in limbic cortex and subcortex areas was consistent with a stress response due to thermal perception and restraint, not a direct interaction of IRIDIUM energy with brain tissue.
Kol'tsov IuV, Korolev VN, Kusakin SA, · 1999
Researchers studied the effect of two-step exposure of bacterial objects to infrared laser and microwave pulse radiations. The effect depends on the time interval between two excitation steps and pulse duration. The biologically active dose of microwave radiation is much lower than that of infrared laser radiation, but laser radiation induces a stronger cellular response. Microwaves enhance the efficiency of infrared laser radiation.
Paul Raj R, Behari J, Rao AR · 1999
The effect of exposing rats to amplitude-modulated radiofrequency radiation (112 MHz modulated to 16 Hz) during development and growth was examined. Wistar rats 35 days old exposed at 1.0 mW/cm2 (SAR 0.75 W/kg) for 35 days showed enhanced ornithine decarboxylase activity and Ca2+ efflux in brain.
E.G Novoselova, E.E Fesenko, V.R Makar, V.B Sadovnikov · 1999
Researchers tested the effect of 8.15–18 GHz microwave radiation at a power density of 1 μW/cm2 on TNF production and immune response. A single 5-hour whole-body exposure induced a significant increase in TNF production in peritoneal macrophages and splenic T cells, and the mitogenic response in T lymphocytes also increased. The activation of cellular immunity was observed within 3 days after exposure. A diet containing β-carotene, α-tocopherol, and ubiquinone Q9 increased the activity of macrophages and T cells from irradiated mice.
Fesenko EE et al. · 1999
Researchers investigated how weak electromagnetic waves in the centimeter range affected the cytotoxic activity of natural killer cells in mice. Irradiation at 8.15 to 18 GHz at 1 microwatt per square centimeter increased the cytotoxic activity of natural killer cells of rat spleen. In mice exposed for 24 to 72 hours, natural killer cell activity increased by 130 to 150%, and this elevated activity persisted for 24 hours after exposure ended. Microwave irradiation of animals in vivo for 3.5 and 5 hours, and a short exposure of splenic cells in vitro, did not affect natural killer cell activity.
Galat VV et al. · 1999
Researchers investigated the effects of nonthermal millimeter-range electromagnetic radiation on early development of mouse and sea urchin embryos. An MRTA-01E-03 generator with a frequency of 54-78 GHz and radiation intensity of 0.06 mWt/cm2 was used, and embryos were irradiated for 30 minutes at the two-blastomere stage. More mouse embryos reached the blastocyst stage (97.3%) compared with controls (87.5%), and the total cultivation time to reach that stage was shorter (72 h) than in controls (96 h). For sea urchin embryos, the radiation had an effect only when embryos with weakened viability were tested.
Fesenko, EE, Makar, VR, Novoselova, EG, Sadovnikov, VB, · 1999
Researchers exposed male NMRI mice to whole body microwave irradiation at 8.15-18 GHz and a power density of 1 microW/cm2 and measured tumor necrosis factor (TNF) production in immune cells. Shorter exposures ranging from 5 hours to 3 days significantly enhanced TNF production in peritoneal macrophages and splenic T lymphocytes. Chronic irradiation for 7 days decreased TNF production in peritoneal macrophages. Microwave treatment increased endogenously produced TNF more effectively than lipopolysaccharide, described as one of the most potent stimuli of this cytokine.
Dmoch A, Moszczynski P · 1998
Shckorbatov YG et al. · 1998
Researchers studied changes in electrokinetic properties and heterochromatin granules in human buccal epithelium cell nuclei under electromagnetic fields in vitro. Cells were irradiated using a semiconductor generator at 42.2 GHz (7.1 mm wavelength) with a Yav-1 apparatus. Irradiation decreased nuclear electric charge and increased chromatin condensation, with effects varying by dose and donor.
Pavel A, Ungureanu CE, Bara II, Gassner P, Creanga DE · 1998
Researchers exposed wheat seeds with uniform genetic background to a microwave flow at 9.75 GHz and low intensity at various doses. Compared to controls, exposed seeds showed chromosomal aberrations including delayed chromosomes, micronuclei, interchromosomal bridges, and chromosomal fragments. The effects of microwaves at various doses on mitotic activity were also followed.
