Trosic I · 2001
Researchers exposed rats to 2450 MHz microwaves at power densities of 5 to 15 mW/cm², in sessions of two hours each, with groups receiving 2, 8, 13, or 22 treatments. Multinucleated cells significantly increased (p<0.01) in treated animals, with the elevation being time- and dose-dependent. Cell viability did not significantly change in the irradiated animal group compared with the control group.
Unknown authors · 2000
This 2000 case-control study examined 469 brain cancer patients and 422 matched controls across five U.S. medical centers to investigate whether handheld cell phone use increases brain cancer risk. Researchers found no overall increased risk, with users actually showing slightly lower odds ratios compared to non-users, though they noted more brain tumors occurred on the same side of the head where phones were used. The study acknowledged important limitations including short average use duration (under 3 years) and the need for longer-term data to assess slow-growing tumors.
Wang, BM, Lai, H · 2000
Rats were trained in six sessions to locate a submerged platform in a circular water maze. They were exposed to pulsed 2450-MHz microwaves for 1 hour before each training session. Microwave-exposed rats were slower than sham-exposed and cage control rats in learning to locate the platform. During the probe trial, microwave-exposed animals spent significantly less time in the quadrant that had contained the platform. There was no significant difference in swim speed among the three groups.
Unknown authors · 2000
Researchers exposed rats to pulsed 2450-MHz microwaves (similar to microwave oven frequency) for one hour before each water maze training session. The microwave-exposed rats were significantly slower to learn the maze and showed impaired spatial memory compared to unexposed controls. The findings suggest that even brief exposure to pulsed microwaves can disrupt learning and memory formation.
Unknown authors · 2000
Researchers exposed rats to pulsed 2450-MHz microwaves (similar to microwave oven frequency) for one hour before each training session in a water maze test. The microwave-exposed rats learned significantly slower and showed impaired spatial memory compared to unexposed controls, suggesting the radiation disrupted their ability to navigate and remember locations.
Unknown authors · 2000
Researchers exposed rats to pulsed 2450 MHz microwaves (similar to microwave oven frequency) for one hour before each training session in a water maze learning task. The microwave-exposed rats took longer to learn the maze location and showed impaired spatial memory compared to control groups. This suggests that acute microwave exposure can interfere with learning and memory processes in the brain.
Vijayalaxmi, Leal BZ, Szilagyi M, Prihoda TJ, Meltz ML, · 2000
Researchers exposed human blood cells to 2450 MHz radiofrequency radiation (the same frequency used in microwave ovens and some WiFi) for 2 hours to see if it would damage DNA. They found no evidence of DNA damage - the cells looked identical to unexposed cells, while cells exposed to ionizing radiation showed clear damage. This suggests that RF radiation at these levels doesn't break DNA strands in human immune cells.
Peinnequin A et al. · 2000
Unknown authors · 2000
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.
