Meltz ML, Eagan P, Erwin DN · 1990
Researchers studied forward mutation at the thymidine kinase locus in L5178Y mouse leukemic cells exposed to 2.45-GHz pulsed-wave RFR and proflavin. Exposures used 500 or 600 W net forward power, giving a SAR of approximately 40 W/kg, for 4 hours with temperature controls. No statistically significant increase in mutant frequency was found with combined RFR and proflavin versus proflavin alone, no change in colony-size distribution occurred, and RFR alone showed no mutagenic action.
Cleary SF, Liu LM, Merchant RE · 1990
Researchers exposed whole human blood in vitro for 2 hours to 27 or 2,450 MHz radio-frequency electromagnetic radiation under isothermal conditions at 37 degrees C. At SARs below 50 W/kg, exposure produced a dose-dependent, statistically significant increase in lymphocyte proliferation, while exposure at 50 W/kg or higher suppressed proliferation relative to sham-exposed cells. The researchers concluded that these biphasic, dose-dependent effects on lymphocyte proliferation were not dependent on heating. There were no detectable effects of RF radiation on lymphocyte morphology or viability.
Mancinelli F et al. · 2004
Researchers exposed tuna myoglobin solutions at pH 3.0 to a 1.95 MHz microwave field for 3 hours at a specific absorption rate of 51±1 mW/g. They monitored heme site refolding by measuring molecular absorption in the Soret spectral region and fitted the data to a bi-exponential model. The kinetics of exposed samples appeared slowered by the microwave field. The tryptophanyl lifetime distribution of the exposed protein appeared sharper than that of non-exposed samples. The researchers suggested that microwave fields could affect the propensity of myoglobin molecules to populate specific conformational substates and alter aggregation during folding, representing a potential misfolding risk.
Lange DG, D'Antuono ME, Timm RR, Ishii TK, Fujimoto JM. · 1993
Field AS, Ginsburg K, Lin JC · 1993
Researchers studied the effects of pulsed microwaves on membrane input resistance and action potential interval statistics in spontaneously active ganglion neurons of land snails (Helix aspersa). Experiments were conducted at strictly constant temperature, so macroscopic heating was not responsible for any observed effects. Exposure significantly increased mean input resistance, while mean firing rate and mean input current were not affected. The net input current was found to be more variable in exposed neurons, though changes in interspike interval standard deviation and input current autocorrelation were not consistent across neurons.
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.
Pakhomov AG, Dubovick BV, Degtyariov IG, Pronkevich AN · 1995
Kojima M et al. · 2004
Researchers exposed one eye each of 43 male pigmented rabbits to microwaves at 300 mW/cm2, either under systemic anesthesia or without anesthesia. Exposed eyes showed miosis, conjunctival congestion, corneal edema, and increased light scattering in the lens, and all of these anterior ocular changes disappeared within a week. Rabbits under systemic anesthesia showed much stronger symptoms, and their ocular temperatures were 2-9 degrees C higher than those without anesthesia.
Krause D, Mullins JM, Penafiel LM, Meister R, Nardone RM, · 1991
Researchers studied the effects of 2.45-GHz continuous-wave microwaves on interferon-regulated enzymes in murine L929 cells. Radioactive 2-5A binding to RNase L was 14.5% above control in sham-exposed samples and 36.4% above control in microwave-exposed samples. RNase L specific activity rose along with the increased 2-5A binding, but 2-5A synthetase specific activity showed no change. No detectable differences were noted in cell viability, plating efficiency, or proliferation rate after exposure.
Arthur W. Guy · 1977
NIOSH researchers developed a specialized laboratory system in 1977 for exposing cell cultures to radiofrequency (RF) radiation while precisely controlling temperature and electromagnetic field strength. This technical report describes equipment designed to study how RF energy affects living cells under controlled laboratory conditions. The system represented early efforts to standardize RF exposure research and eliminate confounding variables like heat effects.
Arthur W. Guy · 1977
This 1977 NIOSH technical report describes the development of a radiofrequency (RF) cell culture irradiation system capable of controlling both temperature and electromagnetic field strength. The research focused on creating standardized laboratory equipment for studying how RF radiation affects living cells in controlled conditions. This represents early foundational work for understanding cellular responses to electromagnetic field exposure.
Arthur W. Guy · 1977
The system was designed for the National Institute for Occupational Safety and Health to determine human RF exposure thresholds in the frequency range D.C. to 100 MHz. The final design uses concentric stainless steel rings with a teflon bottom that forms a liquid-tight seal compressed by brass retainer clamps.
Unknown authors
Unknown authors
Researchers evaluated three BRH applicators and four microwave hyperthermia applicators by thermographically analyzing them using planar phantoms, measuring leakage radiation, net power required to deliver 235 W/kg SAR, and heating patterns. The BRH 2450 MHz applicator had less than 5 mW/cm² leakage for both direct contact and 1 cm spacing, while the 915 MHz applicators exceeded that level when spaced 1 cm from the phantom. The depth of penetration into muscle tissue was nearly identical for both frequencies, at about 2 cm beneath the fat-muscle interface.
Howard I. Bassen et al. · 1978
This 1978 government report investigated electromagnetic radiation leakage from microwave diathermy machines, which use focused microwave energy for deep tissue heating in medical treatments. The study measured how much microwave radiation escaped from these therapeutic devices when used on human patients and laboratory test models. This research was part of early efforts to understand occupational and patient exposure risks from medical microwave equipment.
Howard I. Bassen et al. · 1978
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.
Walters TJ et al. · 1998
Researchers measured hypothalamic, cortical, tympanic, and rectal temperatures in rats exposed to 2.06 GHz microwave radiation at two power densities. The high-power density was 1700 mW/cm² with specific absorption rates of 1224 W/kg in hypothalamus and 493 W/kg in cortex, while the low-power density was 170 mW/cm² with SARs of 122.4 W/kg and 49.3 W/kg. During high-power exposure, the hypothalamic temperature rose significantly faster than cortical or rectal temperatures, whereas low-power exposure produced more uniform heating. For comparison, warm-water immersion produced uniform heating, while warm ambient exposure and exercise maintained the pre-existing temperature gradient between hypothalamus and cortex.
Brown DO, Lu ST, Elson EC · 1994
Researchers studied microwave evoked body movements in mice using head and neck exposure to pulsed and gated continuous wave 1.25 GHz microwaves delivered via a resonant cavity. The incidence of body movements increased proportionally with specific absorption dose when the whole-body average specific absorption rate was held constant at 7300 W/kg, reaching a plateau at 0.9 kJ/kg. For doses higher than 0.9 kJ/kg, response incidence was proportional to the specific absorption rate and reached a plateau at 900 W/kg.
Chemeris NK et al. · 2004
Researchers investigated genotoxic effects of HPPP EMF (8.8 GHz, 180 ns pulse width, peak power 65 kW, repetition rate 50 Hz) on erythrocytes of the frog Xenopus laevis. They used the alkaline comet assay to assess DNA single-strand breaks and alkali-labile lesions. Blood samples were exposed for 40 minutes in a rectangular waveguide with a specific absorption rate of about 1.6 kW/kg. The temperature rise in blood samples at steady state was 3.5 +/- 0.1 degrees C, and the increase in DNA damage was induced by this temperature rise.
Pakhomov AG et al. · 2000
Researchers compared extremely high power microwave pulses (EHPP) with low power pulses (LPP) at 9.2 GHz on isolated, spontaneously beating frog heart slices. Both exposure types produced the same temperature rise because EHPP train duration and average power were matched to LPP. The effects were proportional to heating, fully reversible, and reproducible with no delayed or irreversible effects observed. A single EHPP train or LPP immediately decreased the inter-beat interval in most cases. Temporary arrest of beats could be observed when microwave heating exceeded physiologically tolerable limits, regardless of exposure type.
Pakhomov AG · 1993
Researchers investigated effects of 915 MHz pulsed microwave radiation with peak SAR 20-30 W/g on isolated frog nerve cords. Nerve heating did not exceed 2.2°C due to intense Ringer's solution perfusion. Irradiation during stimulation significantly decreased action potential amplitude and peak latency, while conventional heating increased amplitude, supporting a non-thermal mechanism.
Seaman RL, Beblo DA · 1992
Researchers presented single 1.25-GHz microwave pulses of 0.8- to 1.0-microseconds duration to four rats 100 ms before a startle-inducing acoustic stimulus. At a lower energy dose of 22-43 mJ/kg per pulse, the mean startle latency was longer and the mean amplitude was smaller compared to control responses to acoustic stimuli alone. At a higher energy dose of 59-107 mJ/kg per pulse, the mean latency and amplitude were not statistically different from controls.
