Vijayalaxmi et al. · 2001
Researchers exposed peripheral blood samples from four healthy nonsmoking volunteers to 847.74 MHz CDMA radiation at SARs of 4.9 or 5.5 W/kg for 24 hours. Sham-exposed and gamma-irradiated (1.5 Gy) samples served as controls. No significant differences were found between RF-exposed and sham-exposed lymphocytes in mitotic indices, frequencies of exchange aberrations, excess fragments, binucleate cells, or micronuclei. Gamma-irradiated lymphocytes showed significantly different responses for all indices compared to both RF-exposed and sham-exposed cells. The authors concluded there was no evidence for induction of chromosome aberrations and micronuclei under these exposure conditions.
Vijayalaxmi et al. · 2001
Researchers exposed diluted peripheral blood from four healthy volunteers to 835.62 MHz RF radiation at SARs of 4.4 or 5.0 W/kg for 24 hours. Sham-exposed and gamma-irradiated (1.50 Gy) samples served as negative and positive controls, and lymphocytes were cultured for 48 or 72 hours to assess chromosomal aberrations, micronuclei, mitotic indices, and binucleate cells. No significant differences were found between RF-exposed and sham-exposed lymphocytes for any of the measured endpoints, while gamma radiation produced significantly different responses. The authors concluded there is no evidence for induction of chromosomal aberrations and micronuclei under these exposure conditions.
Maes A, Collier M, Verschaeve L · 2001
Researchers investigated cytogenetic effects of 900 MHz radiofrequency fields using chromosome aberration and sister chromatid exchange frequency methods. They studied three exposure modes (continuous, pseudo-random, dummy burst) at power outputs from 0 to 50 W. Specific absorption rates ranged from 0 to 10 W/kg. The study examined effects of radiation alone and combined with mitomycin C and X-rays. Overall, no mutagenic or co-mutagenic effect was found.
Dabrowski MP, Stankiewicz W, Sobiczewska E, Szmigielski S. · 2001
The study aimed to investigate immunotropic effects of electromagnetic fields in the radio- and microwave frequency range. The authors based their presentation on reviewed literature and their own experiments. They concluded that more systematic and multidisciplinary investigations should be undertaken covering the wide spectrum of immune homeostatic tasks.
Fabbro-Peray P, Daures JP, Rossi JF. · 2001
Researchers performed a population-based case-control study in Languedoc-Roussillon, southern France, from 1992 to 1996, enrolling four hundred and forty-five NHL cases and one thousand and twenty-five population controls. Multivariate analysis identified significantly increased odds for previous hematopoietic malignancy, history of hives, benzene exposure exceeding 810 days, daily welding, and radio operator activity. Agricultural professionals showed a slight, non-significant elevation in odds compared with non-professionals. All results were adjusted for age, gender, education level, and urban setting.
Bastide M, Youbibier-Simoa BJ, Lebecq JC, Giaimis J. · 2001
Researchers investigated continuous exposure of chick embryos and young chickens to EMFs from video display units and GSM cell phone radiation, including radiation attenuated by copper gauze. Permanent exposure to VDU EMFs was associated with significantly increased fetal loss (47-68%) and markedly depressed levels of circulating specific antibodies (lgG), corticosterone and melatonin. Under chronic exposure, GSM cell phone radiation was harmful to chick embryos, stressful for healthy mice, and synergistic with cancer by depleting stress hormones in mice. The same pathological results occurred after substantial reduction of microwaves by copper gauze attenuation.
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.
Lushnikov et al. · 2001
Researchers exposed healthy male NMRI mice to 42.0 GHz electromagnetic radiation at an energy flux density of 0.15 mW/cm2 under several different exposure regimes. After repeated exposures for 20 days before immunization, thymic cellularity was reduced by 17.5% and spleen cellularity by 14.5%, both statistically significant. The humoral immune response itself did not change significantly under any of the exposure regimes tested.
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.
Boscol P et al. · 2001
The study investigated the immune systems of 19 women with a mean age of 35 years who had been exposed to electromagnetic fields from radiotelevision broadcasting stations in their residential area for at least 2 years, with a mean exposure duration of 13 years. The exposed group had mean field levels of 4.3 plus or minus 1.4 V/m in the range 500 KHz to 3 GHz, while the control group had nearby residential exposure of less than 1.8 V/m. The exposed women showed statistically significant reductions in several immune cell types and lower in vitro production of IL-2 and interferon-gamma by peripheral blood mononuclear cells. The researchers concluded that high frequency electromagnetic fields reduce cytotoxic activity in the peripheral blood of women without a dose-response effect.
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.
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.
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.
Unknown authors · 2000
Researchers attempted to replicate earlier findings by testing whether a 1.5-G 50-Hz magnetic field alters intracellular free calcium in Jurkat lymphocyte T-cells. Cells were randomly assigned to magnetic field, sham field, or no-field exposures for 8 minutes each in a blinded design. The percentage of cells showing calcium transients was 16.5% for magnetic field, 14.6% for sham, and 14.2% for no field, with no statistically significant differences among them. The authors concluded that their methods did not identify responsive cells, if such cells exist, and that the results do not rule out a magnetic field effect on calcium.
Unknown authors · 2000
The article reviews reports of skin and heart symptoms in people exposed to video display terminals. Recent studies cited indicate that electromagnetic fields can affect mast cells and dendritic cells and may degranulate them. The model suggests that degranulation of mast cells and dendritic cells releases histamine, which can cause local erythema, edema, itch, and pain, and somatostatin, which may produce sensations of ongoing inflammation and sensitivity to ordinary light.
Unknown authors · 2000
Researchers examined the effect of 50 mT, 60 Hz ELFMF on heat-induced HSP-70 expression in HL60RG cells. Exposure to 50 mT ELFMF alone did not increase HSP-70 production. Combined exposure to 50 mT ELFMF and mild heat at 40°C and 42°C suppressed heat-induced HSP-70 expression. This suppression required simultaneous exposure for more than 5 hours. Lower magnetic densities of 5 mT and 0.5 mT did not suppress HSP-70.
Morgan RW et al. · 2000
Researchers conducted a large cohort mortality study among 195,775 Motorola employees from 1976 to 1996, classifying workers into high, moderate, low, and background radiofrequency exposure groups. Standardized mortality ratios for radiofrequency-exposed workers were 0.53 for brain cancers and 0.54 for lymphomas and leukemias. Internal rate ratios were near 1.0 for brain cancers and below 1.0 for lymphomas and leukemias, with no increased risk seen with longer exposure duration or latency. The findings were consistent across different exposure classifications and did not support an association between occupational radiofrequency exposure and these cancers.
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.
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.
Yoshikawa T et al. · 2000
Gapeev AB, Chemeris NK · 2000
Researchers used a mathematical model to analyze how modulated extremely high frequency electromagnetic radiation affects intracellular calcium concentration in neutrophils. The model showed that the calcium rise depends on both the frequency and phase of the modulating signal relative to chemical stimulation. A rise above 50% of the initial calcium level occurred at about 1 Hz and phase range 0.3-2.5 radians, but only when modulating signal intensity exceeded a threshold and chemical stimulus intensity was high. Added noise changed the phase-frequency characteristics and created multiple response bands with higher Q-factors. The model results matched earlier experimental data showing effects only with extracellular calcium and high calcium ionophore A23187 concentrations.
Del Signore A, Boscolo P, Kouri S, Di Martino G, Giuliano G · 2000
Researchers studied immune responses to electromagnetic fields in atopic and non-atopic women with traffic exposure. Women were divided into groups A, B, C, and D based on atopy and electromagnetic field exposure. Atopic women had reduced in vitro lymphocyte proliferation when stimulated with PHA. Women exposed to electromagnetic fields had lower NK cell levels and lower interferon-gamma production. Atopic women exposed to electromagnetic fields had higher serum IgE than other groups.
Peinnequin A et al. · 2000
Harvey C, French PW · 2000
Researchers exposed a human mast cell line, HMC-1, to continuous wave microwave radiation at 864.3 MHz at an average specific absorption rate of 7 W/kg. Cells were given three exposures each of 20-min duration daily for 7 days. Expression of three genes out of 588 screened was affected, including the proto-oncogene c-kit, the transcription factor Nucleoside diphosphate kinase B, and the apoptosis-associated gene DAD-1. No significant effect on morphology or on F-actin distribution was detected.
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.