Lupke M, Rollwitz J, Simkó M. · 2004
Researchers investigated how 50 Hz extremely low frequency magnetic fields activate human cells to release reactive oxygen intermediates. They examined free radical production in human umbilical cord blood-derived monocytes and in human Mono Mac 6 cells. Exposure to 1 mT ELF-MF for 45 minutes produced a significant increase in superoxide radical anion production of up to 1.4 fold and an increase in ROS release of up to 1.2 fold in monocytes. Mono Mac 6 cells showed superoxide radical anion and ROS production of up to 1.4 and 1.5 fold, respectively, leading the researchers to suggest these cells are more sensitive to ELF-MF than monocytes.
Koyama S et al. · 2004
Researchers tested whether an extremely low-frequency magnetic field (ELFMF) could affect mutations caused by hydrogen peroxide in pTN89 plasmids. Mutations were detected in the supF gene carried by the plasmids in Escherichia coli. The mutation frequency was 2.28×10−4 for hydrogen peroxide treatment alone, and 5.81×10−4 when the ELFMF was applied at the same time. No mutations were observed with ELFMF exposure alone, and the researchers indicated that the ELFMF may potentiate hydrogen peroxide-induced mutation.
Ding GR et al. · 2004
Researchers tested whether exposure to an extremely low frequency magnetic field affects hydrogen peroxide-induced cell death in human leukaemia HL-60 cells. Simultaneous treatment with the magnetic field and hydrogen peroxide for 24 hours significantly increased the number of apoptotic and necrotic cells compared with cells treated with hydrogen peroxide alone. The researchers found that active caspase-7 protein levels were higher in cells exposed to both the magnetic field and hydrogen peroxide than in those treated with hydrogen peroxide alone, and that poly(ADP-ribose) polymerase cleavage occurred earlier under combined exposure.
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.
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.
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.
Zhang MB, Jin LF, He JL, Hu J, Zheng W. · 2003
The study aimed to investigate the combined DNA-damaging effects of low-intensity 2,450 MHz microwave radiation with three chemical mutagens on human lymphocyte DNA. Microwave exposure alone did not significantly increase comet tail length compared with controls at 0 h or 21 h incubation. When lymphocytes were incubated with 30.00 micro mol/L or 3.00 micro mol/L MMC, microwave exposure significantly increased comet tail lengths compared with MMC alone. Combinations of microwave with BLM or MMS did not produce significantly greater DNA damage than BLM or MMS alone.
Zeni et al. · 2003
Vijayalaxmi, Sasser LB, Morris JE, Wilson BW, Anderson LE. · 2003
Timed-pregnant Fischer 344 rats and their nursing offspring were exposed to a far-field 1.6 GHz Iridium signal for 2 h/day, 7 days/week. The offspring then received chronic head-only near-field exposure to a 1.6 GHz signal for 2 h/day, 5 days/week over 2 years. Near-field exposures were conducted at brain SARs of 0.16 or 1.6 W/kg. The incidence of micronuclei in bone marrow did not differ significantly between exposed, sham-exposed, and cage control rats.
Port M, Abend M, Romer B, Van Beuningen D. · 2003
Researchers exposed human leukemia HL-60 cells in vitro to high-frequency electromagnetic fields 25 times higher than ICNIRP occupational reference levels. Cells were harvested at 0, 24, 48, and 72 hours after exposure, and apoptosis, micronuclei, abnormal cells, and expression of 1176 genes were measured. No significant changes were found in apoptosis, micronucleation, abnormal cells, or differential gene expression.
Gatta L et al. · 2003
Researchers exposed C57BL/6 mice to 900 MHz GSM-modulated radiation at SAR 1 or 2 W/kg for 2 hours per day over 1, 2, or 4 weeks. The number of spleen cells, percentages of B and T cells, and CD4/CD8 distribution were not altered by exposure. After 1 week of exposure, IFN-gamma production increased, but this effect was not seen after 2 or 4 weeks.
Cranfield CG, Wieser HG, Dobson J. · 2003
Researchers exposed magnetic bacteria to simulated mobile phone RF radiation and found no impact on mortality. Repeat experiments with only the GSM RF component in a waveguide system showed no significant change in cell mortality compared to sham exposures. A nonmagnetite control strain also showed no significant change in mortality between RF and sham samples.
McNamee et al. · 2003
Researchers examined the effect of 24-hour continuous-wave and pulsed-wave 1.9 GHz radiofrequency fields on primary DNA damage and micronucleus induction in human leukocyte cultures. No significant differences in primary DNA damage were observed between sham controls and any exposed cultures when assessed by the alkaline comet assay immediately after exposure. Similarly, no significant differences were found in micronucleus incidence, micronucleated binucleated cells, binucleated cell frequency, or proliferation index between sham and exposed cultures.
De Mattei M et al. · 2003
Researchers exposed bovine articular cartilage explants to a 75 Hz, 2,3 mT electromagnetic field in vitro, with and without interleukin-1. EMF exposure significantly increased proteoglycan synthesis and residual tissue proteoglycan content compared with controls, without affecting proteoglycan release or nitric oxide production. In interleukin-1-treated explants, EMF increased proteoglycan synthesis and kept tissue proteoglycan content at control levels while not changing proteoglycan release. Lactate production increased in both experimental conditions with EMF exposure.
Salford LG, Brun AR, Eberhardt JL, Malmgren L, Persson BRR · 2003
Three groups of eight rats each were exposed for two hours to GSM mobile phone electromagnetic fields of different strengths. The researchers found highly significant evidence for neuronal damage in the cortex, hippocampus, and basal ganglia of exposed rats. The study investigated whether pathological leakage across the blood-brain barrier might be combined with damage to neurons.
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.
Jayanand, Behari J, Lochan R. · 2003
Researchers exposed rats with sciatic neurectomy-induced osteoporosis to modulated pulsed electromagnetic fields at a 14 MHz carrier frequency modulated at 16 Hz with 10 V peak-to-peak amplitude. The exposure produced a statistically significant increase in bone mineral density and a deceleration in the bone resorption process in the femur and tibia. The authors suggest that this effective window of pulsed radio frequency fields may be used therapeutically for osteoporosis treatment.
Irmak MK, Oztas E, Yagmurca M, Fadillioglu E, Bakir B. · 2003
Researchers investigated the influence of electromagnetic radiation from a 900 MHz cellular telephone on Merkel cells in rats. One group of rats was exposed to a cellular telephone in speech position for 30 minutes while another group was sham-exposed under the same conditions. Exposure led to significantly higher exocytotic activity in Merkel cells compared with the sham exposure group.
Hirsch J et al. · 2003
Researchers compared cellular markers of erythrocyte damage with hemolysis indicators to evaluate microwave warming effects on packed red blood cells. Packed red blood cells were warmed in a water bath to temperatures up to 57°C and also to 35°C using a microwave blood warmer. Flow cytometry showed a decrease in the FSC/SSC ratio and antibody binding above 47°C. Free hemoglobin increased up to 25-fold at 52°C, and hemolysis markers rose further after 48 hours at 42°C and 47°C. Microwave warming to 35°C did not significantly change any marker.
Grigor'ev IuG. · 2003
The study aimed to investigate biological effects of mobile phone electromagnetic field on chick embryo using mortality rate as a risk assessment. Chicken embryos were exposed to EMF from a GSM mobile phone during the 21-day embryonic development. The embryo mortality rate in the incubation period increased to 75% versus 16% in the control group.
Gadhia PK, Shah T, Mistry A, Pithawala M, Tamakuwala D. · 2003
Cranfield C, Wieser HG, Al Madan J, Dobson J. · 2003
Researchers tested a bacterial analogue (Magnetospirillum magnetotacticum) that produces intracellular biogenic magnetite similar to that in the human brain. Exposure to mobile phone emissions resulted in a significantly higher proportion of cell death in exposed cultures versus sham exposure (p = 0.037). The authors noted it is not yet clear whether this would extrapolate to a deleterious health effect in humans.
Weisbrot D, Lin H, Ye L, Blank M, Goodman R. · 2003
Researchers exposed fruit flies to a discontinuous RF signal from a GSM multiband phone at 900/1,900 MHz with SAR approximately 1.4 W/kg for 10 days from egg laying through pupation. The non-thermal radiation increased offspring numbers, elevated hsp70 levels, increased SRE DNA-binding, and induced ELK-1 phosphorylation.
Desta AB, Owen RD, Cress LW. · 2003
Researchers exposed L929 murine fibroblast cells to radiofrequency radiation from a time division multiple access wireless phone operating at 835 MHz to determine the effect on ornithine decarboxylase activity. Exposure lasted 8 hours at average specific absorption rates ranging from less than 1 W/kg up to 15 W/kg, after which cells were harvested and ODC activity was measured. No statistically significant difference in ODC activity was found between exposed and sham-exposed cells at non-thermal specific absorption rates. At SARs that caused measurable heating, a dose-dependent decrease in enzymatic activity was observed and was consistent with a comparable decrease caused by non-RF-radiation heating.
de Pomerai DI et al. · 2003
Researchers investigated whether microwave radiation could alter protein conformation without bulk heating. Microwave radiation enhanced the aggregation of bovine serum albumin in vitro in a time- and temperature-dependent manner. Microwave radiation also promoted amyloid fibril formation by bovine insulin at 60 degrees C. These changes in protein conformation were not accompanied by measurable temperature changes, consistent with estimates of specific absorbed radiation of 15-20 mW kg(-1).
