Jauchem JR, Ryan KL, Freidagger MR · 2000
Ketamine-anesthetized male Sprague-Dawley rats were exposed to 1 GHz, 10 GHz, or combined 1 and 10 GHz microwaves at a whole-body specific absorption rate of 12 W/kg. Exposures were conducted in E and H orientations under far-field conditions until lethal temperatures were reached. Survival time was shortest at 1 GHz, intermediate for combined frequencies, and longest at 10 GHz, with most differences statistically significant. Temperature values at most sites for combined exposure fell between those of the single-frequency groups. Arterial blood pressure initially increased then decreased until death, heart rate increased throughout, and patterns were similar across all groups.
Unknown authors · 2000
Nakamura H, Nagase H, Ogino K, Hatta K, Matsuzaki I · 2000
Researchers exposed rats to continuous-wave microwaves at 2 mW/cm² and 2450 MHz for 90 minutes and measured uteroplacental blood flow and hormone levels. Colonic temperature did not change significantly in either virgin or pregnant rats. Microwave exposure decreased uteroplacental blood flow and increased progesterone and PGF2α in pregnant rats but not in virgin rats. Pretreatment with angiotensin II prevented these changes in pregnant rats. Corticosterone increased and estradiol decreased during exposure regardless of pregnancy status or angiotensin II pretreatment.
Vijayalaxmi, Leal BZ, Szilagyi M, Prihoda TJ, Meltz ML · 2000
Human peripheral blood samples from three volunteers were exposed to pulsed-wave 2450 MHz radiofrequency radiation for 2 hours. The exposure used a net forward power of 21 W with an average power density of 5 mW/cm2 and a mean specific absorption rate of 2.135 W/kg. DNA damage was measured using the alkaline comet assay immediately and 4 hours after exposure. No significant differences were found in comet tail length, fluorescence intensity, or tail moment between RF-exposed and sham-exposed lymphocytes at either time point. The response of lymphocytes exposed to ionizing radiation was significantly different from RF-radiation- and sham-exposed cells.
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.
Adair ER, Cobb BL, Mylacraine KS, Kelleher SA, · 1999
Researchers measured thermoregulatory responses in two groups of seven adult volunteers exposed for 45 minutes to whole-body radio-frequency fields at either 450 or 2450 MHz. At each frequency, two power densities were tested at each of three ambient temperatures (24, 28, and 31 degrees C), along with no-RF control conditions. No change in metabolic heat production occurred under any exposure conditions at either frequency. At both frequencies, normalized peak SARs in excess of ANSI/IEEE C95.1 guidelines were easily counteracted by normal thermophysiological mechanisms.
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.
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.
Malyapa RS et al. · 1998
Researchers exposed rats to 2450 MHz microwave radiation (the same frequency used in microwave ovens and some WiFi devices) for 2 hours to see if it would damage DNA in brain cells, as a previous study had suggested. They found no DNA damage in either the brain's cortex or hippocampus regions, contradicting the earlier research. This study suggests that short-term exposure to this type of radiation at moderate levels may not cause immediate genetic damage to brain cells.
Frei et al. · 1998
Researchers exposed 100 C3H/HeJ mice to continuous-wave 2450 MHz RF radiation at 1.0 W/kg for 78 weeks, 20 hours per day, 7 days per week, while 100 mice were sham-exposed. There was no significant difference in mammary tumor incidence between exposed mice (38%) and sham-exposed mice (30%). Latency to tumor onset was similar: 62.5 weeks for exposed mice and 62.0 weeks for sham-exposed mice. Histopathological evaluation found no significant difference in malignant, metastatic, or benign neoplasms between groups.
Novoselova ET, Fesenko EE. · 1998
Researchers studied whether weak electromagnetic waves in the centimeter range could affect tumor necrosis factor production in macrophages from mice. Whole-body microwave irradiation of male NMRI mice, exposure of macrophages in vitro, and irradiation of culture medium with 8.15-18 GHz at a power density of 1 microW/cm2 each caused a significant enhancement of tumor necrosis factor production in peritoneal macrophages.
Nakamura et al. · 1998
Researchers exposed pregnant rats to microwaves at 2 mW/cm2, 2450 MHz for 90 minutes and measured natural killer cell activity and beta-endorphin levels. Microwave exposure raised colonic temperature and increased beta-endorphin in blood and anterior pituitary but did not change corticosterone. Naloxone administered before exposure increased natural killer cell activity and beta-endorphin in blood and placenta of pregnant rats.
Malyapa RS et al. · 1998
Researchers exposed male Sprague-Dawley rats to 2450 MHz continuous-wave microwaves for two hours at 1.2 W/kg specific absorption rate. No significant differences in DNA damage were found between sham-exposed and irradiated rats in either the cerebral cortex or hippocampus, regardless of euthanasia method. Rats euthanized by CO2 asphyxia showed more intrinsic DNA damage and greater experiment-to-experiment variation than those euthanized by guillotine. The authors concluded that guillotine euthanasia is the most appropriate method for DNA damage studies. The study did not confirm previous reports of DNA damage from 2450 MHz microwave exposure.
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.
Malyapa RS et al. · 1997
Researchers used the alkaline comet assay to test whether 2450 MHz radiation causes DNA damage in cultured mammalian cells. Exponentially growing U87MG and C3H 10T1/2 cells were exposed to 2450 MHz CW radiation at SARs of 0.7 and 1.9 W/kg for durations of 2 h, 2 h followed by 4-h incubation, 4 h, and 24 h. No significant differences were observed between the test group and the controls after exposure.
Vijayalaxmi et al. · 1997
C3H/HeJ mice prone to mammary tumors were exposed to 2450 MHz RF radiation at 1.0 W/kg for 20 hours per day, 7 days a week, over 18 months, with sham-exposed controls and positive controls treated with mitomycin C. The incidence of micronuclei in peripheral blood and bone marrow did not differ significantly between RF-exposed and sham-exposed groups. Positive controls treated with mitomycin C showed significantly elevated micronuclei frequencies. A separate analysis of mice that developed mammary tumors also found no significant differences in micronuclei frequency between exposure groups.
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.
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.
Jensh RP · 1997
This review examined whether chronic prenatal microwave exposure in rats caused adverse effects at birth or alterations in offspring development and growth. Pregnant rats were exposed throughout pregnancy to continuous wave 915 MHz, 2450 MHz, or 6000 MHz radiation at power density levels of 10, 20, or 35 mW/cm2, respectively. Animals exposed to 915 MHz did not exhibit any consistent significant alterations in any of the parameters measured. Offspring exposed to 6000 MHz showed an initial slight but significant retardation in term weight, delayed eye opening, lower weekly weights that recovered by the fifth week, and changes in water T-maze and open field performance.
Vijayalaxmi, Mohan, N, Meltz, ML, Wittler, MA, · 1997
Vijayalaxmi, Mohan N, Meltz ML, Wittler MA · 1997
Researchers exposed human blood cells to 2450 MHz radiofrequency radiation (microwave oven frequency) for 90 minutes and found no genetic damage or changes in cell division. The study tested both continuous and intermittent exposure patterns at power levels similar to some industrial microwave applications.
Nakamura H, Seto T, Nagase H, Yoshida M, Dan S, Ogino K. · 1997
Pregnant rats exposed to microwaves showed a significant reduction in splenic natural killer cell activity, while no such reduction was seen in exposed virgin rats. Corticosterone and ACTH increased, and oestradiol decreased, in both exposed virgin and pregnant rats, while beta-endorphin and progesterone increased significantly only in pregnant rats.
Lai H, Carino MA, Singh NP · 1997
Researchers exposed rats to 2450 MHz pulsed radiofrequency radiation at a power density of 2 mW/cm2 for 2 hours and then measured DNA double strand breaks in brain cells. The RFR exposure significantly increased DNA double strand breaks in rat brain cells, and the effect was partially blocked by naltrexone treatment. The researchers concluded that endogenous opioids play a mediating role in RFR-induced DNA strand breaks in brain cells of the rat.
Lai, H, Carino, MA, Singh, NP, · 1997
Researchers exposed rats to 2.45 GHz microwave radiation (the same frequency used in WiFi and microwave ovens) for 2 hours and found it caused DNA double strand breaks in brain cells. When they gave the rats naltrexone, a drug that blocks the body's natural opioids, it partially prevented this DNA damage. This suggests the body's own opioid system plays a role in how microwave radiation damages DNA in brain cells.
Lai, H, Carino, MA, Singh, NP · 1997
Researchers exposed rats to microwave radiation at 2450 MHz (similar to WiFi frequencies) for 2 hours and found significant DNA damage in brain cells. When they gave the rats naltrexone, a drug that blocks the body's natural opioids, the DNA damage was partially prevented. This suggests that microwave radiation triggers the release of natural opioids in the brain, which then contributes to genetic damage.