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.
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.
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.
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.
Aweda MA, Gbenebitse S, Meidinyo RO · 2003
Researchers studied the effects of 2.45 GHz microwave exposure on the lipid peroxidation status of 120 Wistar rats at a power density of 6 mWcm(-2). Lipid peroxidation status in the rats was monitored for 8 weeks after irradiation using the thiobarbituric acid method. Microwave exposure raised the lipid peroxidation status from a mean control value of 4.18 x 10(-6)g 1(-1) to a maximum of 6.50 x 10(-6) g 1(-1) within the first 24 hours, after which it gradually returned toward the control value. The results demonstrated that microwave exposures cause a significant increase in lipid peroxidation status and that ascorbic acid and alpha-tocopherol had protective effects.
Mashevich M et al. · 2003
Researchers examined whether in vitro exposure of human peripheral blood lymphocytes to continuous 830 MHz electromagnetic fields causes losses and gains of chromosomes, a condition called aneuploidy. Cells were irradiated at SAR levels ranging from 1.6 to 8.8 W/kg for 72 hours. A linear increase in chromosome 17 aneuploidy was observed as a function of the SAR value, which the researchers described as a genotoxic effect. Control experiments conducted without any RF radiation across a temperature range of 34.5 to 38.5 °C showed that elevated temperature was not associated with the increased aneuploidy or the changes in centromeric DNA replication seen after RF exposure.
Pakhomov AG, Gaj ek P, Allen L, Stuck BE, Murphy MR · 2002
Researchers compared bioeffects of continuous wave and extremely high power pulse microwaves at 9.3 GHz and 1.25 W average power using yeast cell density in agarose gel. Cell density was strongly affected by irradiation and correlated with local temperature rise, but no statistically significant difference between CW and EHPP was found across the SAR range. A trend (P<0.1) for a difference appeared at average SAR of 100 W/kg and higher, corresponding to peak SAR above 20 MW/kg for EHPP.
Logani MK, Agelan A, Ziskin MC. · 2002
The study examined the effect of millimeter electromagnetic waves on catalase activity in mouse blood to understand mechanisms involved in its reduction. SKH-1 hairless mice were irradiated on their midbacks with 42.2±0.2 GHz millimeter waves at an incident power density of 31±5 mW/cm2 and a peak SAR of 622±100 W/kg. MW irradiation before or after cyclophosphamide administration did not significantly reduce the toxic effect of cyclophosphamide on catalase activity in mouse blood.
McNamee JP et al. · 2002
Blood cultures from human volunteers were exposed to an acute 1.9 GHz pulse-modulated radiofrequency (RF) field for 2 h using a series of six circularly polarized, cylindrical waveguides. Mean specific absorption rates (SARs) ranged from 0 to 10 W/kg and the temperature within the cultures during the exposure was maintained at 37.0 ± 0.5°C. DNA damage was quantified in leukocytes by the alkaline comet assay and the cytokinesis-block micronucleus assay. No evidence of increased primary DNA damage was detected by the comet assay and no significant differences in micronucleus frequency were found at any SAR tested.
McNamee JP et al. · 2002
Human blood cultures were exposed to a 1.9 GHz continuous-wave radiofrequency field for 2 hours at SARs of 0.0, 0.1, 0.26, 0.92, 2.4, and 10 W/kg while temperature was maintained at 37.0 ± 0.5°C. DNA damage was measured immediately after exposure using the alkaline comet assay with four parameters, and micronucleus formation was assessed using the cytokinesis-block micronucleus assay. No evidence of increased primary DNA damage was detected at any SAR tested. There was no significant difference in micronucleus incidence between exposed cultures and sham controls at any SAR.
Tafforeau M et al. · 2002
Researchers exposed flax seedlings to a 1-minute cold shock or a 2-hour GSM telephone radiation at 0.9 GHz and observed epidermal meristem production. They performed a SIMS analysis of inorganic cations in hypocotyl tissue from control and calcium-deprived seedlings. The analysis revealed decreases in calcium, sodium, and potassium and an increase in magnesium without substantially changing the divalent-to-monovalent cation ratio.
Stopczyk D et al. · 2002
Researchers assessed the effect of mobile phone electromagnetic fields on SOD-1 activity and MDA level in human blood platelets exposed to 900 MHz for 1, 3, 5, and 7 minutes. SOD-1 activity was significantly depleted after 1, 5, and 7 minutes of exposure and increased after 3 minutes compared with controls. MDA concentration increased significantly after 1, 5, and 7 minutes and decreased after 3 minutes compared with controls. The authors concluded that oxidative stress from microwave exposure may cause adverse cellular changes and systemic disturbances.
Pologea-Moraru R, Kovacs E, Iliescu KR, Calota V, Sajin G · 2002
Researchers studied the effects of low-power microwaves at 2.45 GHz on the membrane fluidity of rod photoreceptor cells. The researchers expected the retina to be very sensitive to microwave irradiation due to the polar character of photoreceptor cells and high water content.
Pacini S et al. · 2002
Researchers exposed human skin fibroblasts to GSM cellular phone radiofrequency for 1 hour. GSM exposure induced alterations in cell morphology and increased expression of mitogenic signal transduction genes, cell growth inhibitors, and apoptosis-related genes. A significant increase in DNA synthesis and intracellular mitogenic second messenger formation corresponded with high expression of MAP kinase family genes.
Higuchi Y et al. · 2002
Researchers performed a left-sided hemilaminectomy in adult Sprague-Dawley rats to expose the C6 dorsal root ganglion. Rats received pulsed radiofrequency, continuous radiofrequency, or sham treatment with the electrode on the ganglion for 120 seconds. Pulsed radiofrequency significantly increased cFOS-immunoreactive neurons in the superficial dorsal horn laminae three hours after treatment, while continuous radiofrequency did not. The authors concluded that pulsed radiofrequency activates pain-processing neurons in the dorsal horn without tissue heating.
Beason RC, Semm P. · 2002
Researchers investigated the effects of a pulsed 900 MHz signal modulated at 217 Hz on avian brain neurons. The stimulation changed neural activity in more than half of the brain cells. 76% of responding cells increased their firing rates by an average of 3.5-fold. The remaining responding cells decreased their spontaneous activity rates. The authors suggested these responses indicate potential effects on humans using hand-held cellular phones.
Irmak MK et al. · 2002
Researchers investigated the influence of electromagnetic radiation from a digital GSM mobile telephone at 900 MHz on oxidant and antioxidant levels in rabbits. They measured adenosine deaminase, xanthine oxidase, catalase, myeloperoxidase, superoxide dismutase, glutathione peroxidase activities, nitric oxide, and malondialdehyde levels in sera and brains of exposed and sham-exposed rabbits. Serum SOD activity increased and serum NO levels decreased in exposed rabbits compared to sham-exposed rabbits, while other parameters did not change.
Tice RR, Hook GG, Donner M, McRee DI, Guy AW. · 2002
DNA damage in leukocytes was assessed with the alkaline comet assay and chromosomal damage in lymphocytes with the micronucleus assay. No significant increase in DNA damage was seen after 3 or 24 hours, and no increase in micronucleated lymphocytes occurred after 3 hours. However, 24-hour exposures at 5.0 or 10.0 W/kg significantly increased micronucleated lymphocytes about fourfold, regardless of signal type, modulation, or frequency.
Testylier G, Tonduli L, Malabiau R, Debouzy JC · 2002
Rats were exposed to 2.45 GHz continuous wave at 2 or 4 mW/cm(2) for 1 h during the day, or to 800 MHz modulated at 32 Hz at 200 mW/cm(2) for 1 or 14 h during the night. Exposure at 4 mW/cm(2) caused a significant 40% decrease in mean acetylcholine release from hippocampus, maximal at 5 h post exposure. Fourteen-hour nighttime exposure at 800 MHz induced a significant 43% decrease in acetylcholine release during 11 p.m.-4 a.m. compared to control rats.
Paulraj R, Behari J · 2002
Researchers exposed 35-day-old Wistar rats to low-level continuous 2.45 GHz microwaves for 2 hr/day over 35 days at a power density of 0.34 mW/cm2 with a specific absorption rate of 0.1 W/kg. Exposed rats showed a significant increase in calcium ion efflux and ornithine decarboxylase activity and a significant decrease in calcium-dependent protein kinase activity in brain tissue. The authors suggested that the radiation affects membrane-bound enzymes linked to cell proliferation and differentiation, indicating a possible tumor-promoting role.
