Unknown authors · 1999
Groups of 100 female Sprague–Dawley rats were initiated with a single 10 mg gavage dose of DMBA at 50 days of age and then exposed to ambient fields, 50 Hz magnetic fields at 1 or 5 Gauss, or 60 Hz fields at 1 Gauss for 18.5 hours per day, 7 days per week for 26 weeks. There was no effect of magnetic field exposure on body weight gains or the time of appearance of mammary tumors. Carcinoma incidence was 96%, 90%, 95%, and 85% for the DMBA controls, 1 G 50 Hz, 5 G 50 Hz, and 1 G 60 Hz groups respectively, total carcinoma numbers were 649, 494, 547, and 433 with significant decreases in the 1 G 50 Hz and 1 G 60 Hz groups, and the authors concluded there was no evidence that 50 or 60 Hz magnetic fields promoted breast cancer under the conditions of this assay.
Unknown authors · 1999
Unknown authors · 1999
Researchers exposed groups of 100 female Sprague-Dawley rats to 50 Hz magnetic fields at 1 or 5 G, or 60 Hz at 1 G, for 18.5 hours a day, 7 days a week, for 13 weeks after initiating mammary tumors with DMBA. A second study used a lower DMBA dose of 2 mg and exposed rats to 50 Hz fields at 1 or 5 G for the same duration. Magnetic field exposure did not affect body weight, tumor latency, or tumor size in either study, and the authors concluded there was no evidence that 50 or 60 Hz fields promoted breast cancer.
Vijayalaxmi et al. · 1999
Peripheral blood and bone marrow smears were examined for micronuclei in polychromatic erythrocytes at 18 and 24 hours after exposure. No statistically significant differences were found in micronuclei frequency or percentage of polychromatic erythrocytes between exposed mice and controls.
Nelson BK, Snyder DL, Shaw PB · 1999
The purpose was to determine if synergistic effects of radiofrequency radiation and 2-methoxyethanol generalize to other chemicals. Rats received salicylic acid at 0, 250, or 350 mg/kg by gavage on gestation day 9 or 13. Rats given salicylic acid on day 9 were exposed to radiofrequency radiation sufficient to maintain colonic temperature at 41 degrees C for 60 minutes or received a sham exposure, while those given salicylic acid on day 13 also received 0 or 100 mg/kg 2-methoxyethanol by gavage. Fetuses were examined for external malformations on gestation day 20.
Miller SA, Bronson ME, Murphy MR · 1999
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.
Jauchem JR, Frei MR, Ryan KL, Merritt JH, Murphy MR · 1999
The study investigated the lack of effects on heart rate and blood pressure in ketamine-anesthetized rats briefly exposed to ultra-wideband electromagnetic pulses. Exposures at a repetition frequency of 1 kHz for 0.5 s or to repetitive pulse trains for a total of 2 min resulted in no significant changes in heart rate or mean arterial blood pressure. These results suggest that acute whole-body exposure to UWB pulses does not have a detrimental effect on the cardiovascular system.
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.
Chagnaud, JL, Moreau, JM, Veyret, B · 1999
Two-month-old female Sprague-Dawley rats were treated by injection of benzo(a)pyrene and irradiated with GSM (Global System for Mobile)-modulated 900-MHz microwaves in an anechoic chamber at 55 or 200 mu W cm-2 (75 and 270mWkg-1 average whole-body SAR, 2h daily for 2 weeks). Microwave exposure had no effect on tumour development, no acceleration or delays in tumour onset were observed, and animal survival was not modified while serum auto-antibody levels were similar in exposed and sham-exposed groups.
Chagnaud JL, Veyret B · 1999
Researchers investigated the effects of GSM-modulated microwaves on lymphocyte sub-populations and mitogenic responses in Sprague-Dawley rats. No alterations were found in the surface phenotype of splenic lymphocytes or in their mitogenic activity.
Wu Y, Jia Y, Guo Y, Zheng Z · 1999
Wistar rats were divided into four groups with three exposure groups and one control group, and learning was measured with a Y-maze followed by neurotransmitter detection in brain areas. Learning ability decreased in exposure groups over three days of EMP exposure compared with controls. After one day, hippocampal 5-HT and DOPAC increased and hypothalamic dopamine increased while hypothalamic Adr decreased; after the second day, hippocampal Adr and 5-HT reduced; after the third day, hippocampal Adr remained lower than control.
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.
Belousova TE, Kargina-Terent'eva RA · 1999
Researchers examined adrenergic cardiac and adrenal nervous plexuses in normotensive and spontaneously hypertensive rats using quantitative neurohistochemical methods before and after exposure to a Bayur microwave therapy apparatus at 42,194 MHz and 53,534 MHz. Exposure reduced myocardial nerve plexus density and catecholamine luminescence in the heart, and decreased adrenal gland relative weight and catecholamine luminescence in the adrenal medulla of hypertensive rats.
Adey WR et al. · 1999
Researchers tested an 836.55 MHz NADC-modulated field in a 2-year bioassay with fetal exposure in Fischer 344 rats. Of 236 original rats, 182 (77%) survived to termination at age 709-712 days. There was no evidence of tumorigenic effects in the CNS from TDMA field exposure. Exposed animals showed trends toward reduced incidence of spontaneous CNS tumors (P < 0.16) and ENU-induced CNS tumors (P < 0.16). In preterm rats where neural tumors caused death, fields decreased ENU-induced tumor incidence (P < 0.03).
Trosic I, Matausicpisl M, Radalj Z, Prlic I, · 1999
The remaining 20 rats served as control. Exposed rats showed a decreasing tendency in total leukocyte and relative lymphocyte counts and a slight increase in granulocyte and erythrocyte counts.
Seaman RL, Belt ML, Doyle JM, Mathur SP · 1999
Researchers investigated the effects of ultra-wideband electromagnetic pulses on L-NAME-induced changes in nociception and locomotor activity in CF-1 mice. Mice were injected with saline or 50 mg/kg L-NAME and exposed for 30 minutes to sham or UWB pulses with specific electric field parameters. UWB exposure eliminated the L-NAME-induced hyperactivity. UWB exposure reduced the L-NAME-induced increase in back-paw-lick latency by 22%, but this reduction was not statistically significant.
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.
Lu ST, Mathur SP, Akyel Y, Lee JC · 1999
Researchers exposed male Wistar-Kyoto rats to ultrawide-band electromagnetic pulses at 0.5-kHz and 1-kHz for 6 minutes. They measured cardiovascular functions including heart rate, systolic, mean, and diastolic pressures using a noninvasive tail-cuff sphygmomanometer. Exposure caused a significant decrease in arterial blood pressure that was robust, consistent, and persistent, while heart rate did not change. Cardiovascular functions were evaluated from 45 minutes to 4 weeks after exposure.
Kemerov, S, Marinkev, M, Getova, D · 1999
Researchers exposed 24 Wistar rats to low-intensity electromagnetic fields in the meter, decimeter, and centimeter ranges to compare behavioral effects across those ranges. The rats were irradiated on the head area at a power density of 10 mW/cm2, and conditioned and non-conditioned responses along with spontaneous motor activity were studied using a conventional shuttle box. Exposure to EMFs across all three ranges was associated with slowing of conditioned response formation, with the effect most clearly marked in rats exposed to meter EMFs, while effects of centimeter EMFs were delayed in time. The behavioral effects were mild at athermal dosages and the animals adapted easily to exposure conditions.
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.
Dasdag et al. · 1999
