Kues HA et al. · 1992
Researchers exposed anesthetized monkeys to pulsed 2.45 GHz microwaves after topical treatment with timolol maleate or pilocarpine. Drug pretreatment lowered the power-density threshold for corneal endothelial lesions and increased iris vascular permeability from 10 to 1 mW/cm². Effects occurred at an average SAR of 0.26 W/kg and were confirmed with specular microscopy, fluorescein angiography, and horseradish peroxidase tracer techniques.
Belyaev IYa, Alipov YD, Shcheglov VS, Lystsov VN · 1992
Researchers studied the effect of low-intensity microwaves on the conformational state of the genome of X-irradiated E. coli cells using the method of viscosity anomalous time dependencies. The frequency dependence of the observed effect had a resonance nature within the ranges of 51.62-51.84 GHz and 41.25-41.50 GHz, with a resonance half-width of the order of 100 MHz. A power density of 1 microW/cm2 was sufficient to suppress radiation-induced repair of the genome conformational state, across a tested range of 0.1-200 microW/cm2.
Garaj-Vrhovac V, Fucic A, Horvat D · 1992
Researchers exposed human whole-blood samples to continuous microwave radiation at a frequency of 7.7 GHz, at power densities of 0.5, 10, and 30 mW/cm2, for 10, 30, and 60 minutes. In all experimental conditions, the frequency of all types of chromosomal aberrations was significantly higher than in the control samples, and dicentric and ring chromosomes were detected in the irradiated samples. The results showed a positive correlation between micronuclei and specific chromosomal aberrations, including acentric fragments and dicentric chromosomes. The researchers indicated that microwave radiation causes changes in the genome of somatic human cells and that the applied tests are equally sensitive for the detection of the genotoxicity of microwaves.
Khramov RN, Sosunov EA, Koltun SV, Ilyasova EN, Lednev VV · 1991
Researchers studied the effects of super high frequency microwaves (34-78 GHz) on spontaneous firing rates of slowly adapting stretch-receptor neurons in crayfish. Irradiation at power densities up to 250 mW/cm2 caused a transient decrease in firing rate, and after the field was turned off the rate increased and stabilized at pre-exposure levels. Firing rates also increased when the receptor muscle was stretched and were inversely correlated with small temperature increases of about 1.5°C. The response did not depend on frequency when temperature was held constant, and no resonant peaks were found across the millimeter-wave range.
Garson OM, McRobert TL, Campbell LJ, Hocking BA, Gordon I. · 1991
Researchers studied chromosome damage in 38 radio-linemen exposed to radio-frequency radiation and 38 matched controls. They analyzed Two hundred metaphases per person, scored blind, and found the rate of aberrant cells was the same in both groups. There were no statistically significant differences in the types of chromosome aberrations.
Ciaravino V, Meltz ML, Erwin DN · 1991
Researchers exposed Chinese hamster ovary cells to adriamycin and pulsed RFR at 2,450 MHz and 33.8 W/Kg for 2 h. The maximal temperature in the tissue-culture medium was 39.7 +/- 0.2 degrees C. The experiments were controlled for chemical and RFR exposures as well as for temperature. Verified statistically, the data indicate that the RFR did not affect changes in cell progression caused by adriamycin and did not change the number of sister chromatid exchanges induced by adriamycin.
Saalman E et al. · 1991
Researchers studied how 2.45 GHz microwave radiation affects the permeability of unilamellar liposomes containing a fluorescent marker. After 10 minutes of exposure, microwave-treated liposomes showed significantly greater marker release than those heated conventionally. The experiments were conducted above the lipid membrane's phase transition temperature, unlike earlier studies.
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.
Veyret B et al. · 1991
Researchers exposed Balb/C mice to pulsed microwaves at 9.4 GHz, both with and without amplitude modulation at frequencies between 14 and 41 MHz, to assess effects on the immune system. Exposure took place for five consecutive days at 10 hours per day, at a whole-body-averaged SAR of approximately 0.015 W/kg. When the pulsed field was combined with amplitude modulation, immune responses were significantly augmented or weakened depending on the AM frequency used, while the pulsed field alone did not greatly alter immune responsiveness.
Nageswari KS et al. · 1991
Researchers exposed fourteen male Belgian white rabbits to microwave radiation at 5 mW/cm2, 2.1 GHz, three hours daily, six days a week for three months, while seven rabbits received sham exposure for the same duration. Significant suppression of T lymphocyte numbers was found in the microwave group at two months and during follow-up. Despite lower T lymphocyte counts in the blood, no significant variation was observed in tissue T lymphocyte counts, and a functional immune response test showed no impairment.
Brown HD, Chattopadhyay SK · 1991
Researchers studied how 9.14 GHz continuous-wave microwave radiation affected ouabain inhibition of Na+/K+-ATPase from dog kidney. Exposure for 5 minutes to 9.14 GHz radiation at an estimated SAR of 20 W/kg was applied at several stabilized temperatures between 7.0 and 43.8 °C. The efficacy of ouabain as an inhibitor of ATPase activity was severely diminished by the microwave field, and at 24.9 °C a 23% decrease in activity occurred.
Balcer-Kubiczek EK, Harrison GH. · 1991
Researchers exposed actively growing cultures of C3H/10T1/2 cells for 24 hours to 2.45-GHz microwaves pulse-modulated at 120 Hz. The electromagnetic fields alone had no effect on cell survival or induction of neoplastic transformation. When combined with the tumor promoter TPA, the enhancement of transformation was highly significant and ranged up to a level equivalent to that produced by 1.5 Gy of X rays. The frequency of neoplastic transformation was dependent on the level of electromagnetic exposure and was additive with doses of X rays given as a cocarcinogen.
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.
Kerbacher JJ, Meltz ML, Erwin DN, · 1990
Neubauer C, Phelan AM, Kues H, Lange DG · 1990
Researchers exposed male albino rats to 2.45-GHz microwaves with 10-microseconds pulses at 100 pps. Exposure at 10 mW/cm2 for 30 to 120 minutes increased tracer uptake through the blood-brain barrier. The uptake depended on both power density and exposure duration. At 5 mW/cm2, a 15-minute exposure had no effect. Pretreating rats with colchicine nearly completely blocked the microwave-induced uptake.
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.
Garaj-Vrhovac V, Horvat D, Koren Z · 1990
Researchers exposed cultured V79 Chinese hamster cells to continuous microwave radiation at 7.7 GHz and a power density of 30 mW/cm2 for 15, 30, and 60 minutes. The study measured the incorporation of [3H]thymidine into DNA and the frequency of chromosome aberrations. Inhibition of [3H]thymidine incorporation occurred through complete prevention of DNA from entering into the S phase, and the normal rate of incorporation recovered within one generation cycle of V79 cells. Compared with control samples, irradiated cells showed a higher frequency of specific chromosome lesions.
Parker JE, Kiel JL, Winters WD · 1988
Researchers exposed four rodent cell lines to 2450 MHz microwave radiation at a Specific Absorption Rate of 103.5 +/- 4.2 W/kg at temperatures of 37, 40, 42, and 45 degrees C. The researchers extracted mRNA from exposed and sham-exposed cells and used DNA probes of oncogenes, heat shock protein, or long terminal repeat sequences to look for differences in mRNA expression. With the cell lines and probes used, no significant differences in mRNA expression were observed after microwave exposure.
