Klug S, Hetscher M, Giles S, Kohlsmann S, Kramer K, · 1997
Researchers exposed 9.5-day-old rat embryos for up to 36 hours to radiofrequency electric and magnetic fields with modulation frequencies of 16, 60, and 120 Hz. The exposure included electric field strengths of 60 and 600 V/m, magnetic inductions of 0.2 and 2.0 microtesla, and specific absorption rates of 0.2, 1.0, and 5.0 W/kg. Neither the electric nor the magnetic fields interfered significantly with normal embryo growth and differentiation when assessed on day 11.5 using a scoring system, photographs, histology, and protein content.
Ivaschuk OI et al. · 1997
Researchers exposed nerve growth factor-treated PC12 rat pheochromocytoma cells to a packet-modulated 836.55 MHz radiofrequency field at power densities of 0.09, 0.9, and 9 mW/cm2 for 20, 40, or 60 minutes, with an intermittent 20-minute on/off regimen. Sham-exposed cells served as controls, and c-fos and c-jun expression was measured by Northern blot analysis of total RNA. C-fos transcript levels did not change after 20 minutes at any intensity, while c-jun transcripts decreased by 38% only after 20 minutes at 9 mW/cm2.
Gos, P, Eicher, B, Kohli, J, Heyer, WD · 1997
Researchers exposed exponentially growing Saccharomyces cerevisiae cells to electromagnetic fields from 41.682 GHz to 41.710 GHz in 2 MHz increments at power densities of 0.5 and 50 microW/cm2. Cell division was assessed by time-lapse photography using two identical chambers that allowed concurrent control and exposure experiments. Control experiments showed the cells were dividing at submaximal rates, ensuring that any increase or decrease in division rate could be observed. No consistently significant differences were found between exposed and unexposed cells across multiple independent experiment series.
Cain CD, Thomas DL, Adey WR · 1997
The study tested whether a TDMA-modulated RF field and the tumor promoter TPA together increase focus formation of transformed cells cocultured with parental C3H/10T1/2 murine fibroblasts. Cell cultures were exposed to an 836.55 MHz TDMA-modulated field at specific absorption rates of 0.15, 1.5, and 15 μW/g in a repeating cycle of 20 minutes on and 20 minutes off continuously for 28 days. RF exposure did not significantly alter TPA-induced focus formation at any of the tested exposure levels across multiple independent experiments.
Antonopoulos A, Eisenbrandt H, Obe G, · 1997
Human peripheral lymphocytes were incubated in the presence of high-frequency electromagnetic fields of 380, 900 and 1800 MHz. The measured endpoints were cell cycle progression and the frequencies of sister-chromatid exchanges. No differences between treated and control cultures could be found.
Persson BRR, Salford LG, Brun A · 1997
Researchers studied blood-brain barrier permeability in Fischer 344 rats of both sexes exposed to radio frequency electromagnetic fields. The exposure used 915 MHz microwaves delivered as either pulse-modulated or continuous wave signals. The rate of pathological leakage rose from 0.17 in controls to 0.39 across all exposed rats, a highly significant difference. Continuous wave exposure produced a higher rate of pathological rats (0.50 ± 0.07) than pulse-modulated exposure (0.35 ± 0.03), and that difference was also statistically significant.
Rojavin MA, Ziskin MC · 1997
Researchers injected BALB/c mice with ketamine 80 mg/kg or chloral hydrate 450 mg/kg and exposed them to 61.22 GHz millimeter waves at 420 W/kg peak specific absorption rate for 15 minutes. Millimeter wave exposure increased anesthesia duration by about 50% compared to sham exposure, which had no effect.
Gapeev AB, Lakushina VS, Chemeris NK, Fesenko EE · 1997
Researchers investigated how low-intensity modulated extremely high frequency electromagnetic radiation affected the respiratory burst of peritoneal neutrophils from NMRI mice. Continuous radiation at 50 microW/cm2 inhibited the reaction, with a maximum effect of about 25% at a carrier frequency of 41.95 GHz. When modulation was applied at 1 Hz, the reaction was activated, while modulation at 0.1, 16, and 50 Hz inhibited it. The effect was observed only when intracellular free calcium concentration was raised and calcium was flowing through the plasma membrane.
Cleary, SF, Cao, G, Liu, LM, Egle, PM, Shelton, KR · 1997
Researchers investigated stress protein induction in HeLa and CHO cells following a 2-hour exposure to radiofrequency or microwave radiation. Cells were exposed under isothermal conditions maintained at 37 ± 0.2 °C. Neither microwave nor RF radiation had a detectable effect on stress protein induction.
Lai, H, Singh, NP, · 1997
Researchers investigated the effects of microwave exposure on DNA strand breaks in rat brain cells. They found that treating rats with either melatonin or the spin-trap compound PBN immediately before and after radiofrequency electromagnetic radiation exposure blocked the DNA strand breaks. Because both substances are free radical scavengers, the researchers hypothesized that free radicals are involved in the radiofrequency electromagnetic radiation-induced DNA damage.
Ohmoto Y et al. · 1996
Maes A, Collier M, Slaets D, Verschaeve L. · 1996
Researchers exposed whole blood samples to a 954 MHz GSM base station antenna and then cultured lymphocytes with mitomycin C. They measured sister chromatid exchange frequencies in metaphase figures.
Gapeev AB, Safronova VG, Chemeris NK, Fesenko EE · 1996
Researchers compared horn, dielectric, and channel antennas for matching with biological loads. Electromagnetic radiation at 41.8-42.05 GHz inhibited luminol-dependent chemiluminescence of neutrophils activated by opsonized zymosan. No frequency dependence was found in the far field zone, but a quasi-resonance dependence appeared in the near field zone. The channel antenna provided uniform specific absorption rate distribution and wide-band matching in both near and far field zones.
Detlavs I et al. · 1996
Researchers exposed Wistar rats with full-thickness dermal wounds to RF EMF for 30 min daily during the first 5 days using 53.53 GHz without modulation, 42.19 GHz without modulation, and 42.19 GHz with a 200-MHz frequency modulation band. RF EMF without frequency modulation decreased glycoprotein macromolecules and reduced inflammatory exudation and total collagen accumulation. RF EMF with frequency modulation significantly elevated hexoses and sialic acid concentrations, indicating intensified exudative phenomena, and increased collagenous protein accumulation. The authors concluded that non-thermal EMF affects reparative-proliferative processes in soft tissue wounds.
Balode, Z · 1996
Researchers examined micronuclei in bovine peripheral erythrocytes from female Latvian Brown cows near the Skrunda Radar and from a control area. They counted micronuclei in 2000 erythrocytes per animal at 1000x magnification using a simplified Schiff DNA staining method. The exposed group had an average of 0.6 micronuclei per 1000 erythrocytes versus 0.1 per 1000 in controls, a statistically significant difference (P < 0.01).
Wolke S, Neibig U, Elsner R, Gollnick F, Meyer R, · 1996
Urech, M, Eicher, B, Siegenthaler, J · 1996
Researchers conducted field experiments lasting one to three years alongside laboratory tests, exposing Parmelia tiliacea and Hypogymnia physodes to 2.45 GHz microwaves at 0.2, 5, and 50 mW/cm² with a control. Both species showed a substantially reduced growth rate at the highest exposure of 50 mW/cm². Temperature measurements revealed that microwaves at 2.45 GHz and 50 mW/cm² substantially increased lichen surface temperature and accelerated drying. When the same species were exposed near a 9.5 MHz short-wave broadcast transmitter at up to 235 V/m, no visible effects were detected.
Kolosova LI, Akoev GN, Avelev VD, Riabchikova OV, Babu KS · 1996
Researchers examined the effect of low-intensity millimeter wave electromagnetic radiation on regeneration of the rat sciatic nerve after transection and microsurgical reapproximation. At the twentieth postoperative day, treated animals showed a 32% increase in regeneration distance and a 26% increase in conduction velocity compared to controls.
Cleary, SF, Du, Z, Cao, G, Liu, LM, McCrady, C · 1996
Researchers investigated the effects of RF radiation exposure on interleukin 2 (IL-2) -dependent proliferation of cytolytic T lymphocytes (CTLL-2). At specific absorption rates greater than 25 W/kg, exposure produced a consistent, statistically significant reduction in CTLL-2 proliferation, especially at low IL-2 concentrations. At lower SARs, 2450 MHz exposure increased CTLL-2 proliferation immediately after exposure but reduced 24 h postexposure proliferation. The researchers found significant qualitative and quantitative differences between the effects of temperature elevation and RF radiation.
Belyaev IY, Shcheglov VS, Alipov YD, Polunin VA · 1996
Researchers studied how millimeter waves affected the genome conformational state of E. coli AB1157 cells across a frequency range of 51.64 to 51.85 GHz. The resonance frequency of 51.755 GHz did not shift with power density, though the magnitude of the effect differed significantly and depended on the power density of exposure. Sharp narrowing of the 51.755 GHz resonance at lower power densities was followed by an emergence of new resonance frequencies.
Belokhvostov AS et al. · 1995
The study aimed to investigate DNA analysis of retroposon-like genetic LINE elements in blood plasma of rats exposed to radio-diapason electromagnetic waves. The elevation of LINE-elements' DNA level was revealed in blood plasma of rats exposed to electromagnetic waves. The amount of full-size 5'-containing LINE-elements copies was increased especially. The researchers supposed a connection of this effect with retrotransposon activation and genetic instability condition of organism development.
Semin IuA, Shvartsburg LK, Dubovik BV · 1995
Researchers studied the effect of weak radiofrequency radiation on DNA secondary structure stability in vitro. Exposure at 3 or 4 Hz and 0.6 mW/cm2 peak power significantly increased accumulated DNA damage, while other pulse rates or power levels eliminated the effect. DNA was incubated with glycine and formaldehyde, and damage was assessed via thermal denaturation dynamics.
Cao G, Liu LM, Cleary SF · 1995
Researchers exposed synchronized Chinese hamster ovary (CHO) cells to 27 MHz continuous-wave radio-frequency radiation for 2 hours at specific absorption rates of 5 or 25 W kg−1 under isothermal conditions, meaning no heating occurred. The exposure produced time- and dose-rate-dependent cell cycle alterations, with maximum responses occurring 3 days after exposure at a SAR of 25 W kg−1. Cells in G0/G1- or S-phase showed more pronounced alterations, while G2/M-phase cells showed minimal effects at either SAR.
Nelson BK et al. · 1994
Researchers exposed rats to RF radiation that maintained colonic temperature at 42.0 degrees C for 0, 10, 20, or 30 min and to 2ME at doses of 0, 75, 100, 125, or 150 mg/kg on gestation days 9 or 13. Fetuses were examined on gestation day 20 for external, skeletal, and visceral malformations. Synergistic effects were observed for some treatment combinations but not others, with highly significant effects on gestation day 13 but little effect on day 9. Statistical analyses showed no global synergistic effect but evidence of synergism at intermediate dose levels.
Lu Y, Yu J, Ren Y · 1994
Researchers measured dielectric properties of human red blood cells in suspension at 25 degrees C across 1-500 MHz using a coaxial transmission line reflection method. The study included 243 healthy persons with a hematocrit of 50%. The data revealed a statistically significant age dependence with a critical age of about 49 years, above which permittivity and conductivity decreased significantly.
