Zotti-Martelli L, Peccatori M, Scarpato R, Migliore L · 2000
Researchers exposed human peripheral blood lymphocytes in vitro to electromagnetic fields at two frequencies, 2.45 and 7.7 GHz, at power densities of 10, 20, and 30 mW/cm2 for 15, 30, and 60 minutes. At a power density of 30 mW/cm2 and after exposures of 30 and 60 minutes, both frequencies led to an induction of micronuclei compared to control cultures. The researchers concluded that microwaves are able to cause cytogenetic damage in human lymphocytes mainly for both high power density and long exposure time.
de Pomerai D et al. · 2000
Researchers exposed nematode worms (C. elegans) overnight to 750-MHz microwaves at a SAR of 0.001 W/kg and measured levels of heat-shock proteins (HSPs). The worms showed an increase in HSPs following that exposure. The authors argued that the effect on HSPs was non-thermal and suggested that 'current exposure limits for microwave equipment may need to be reconsidered.'
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.
Yoshikawa T et al. · 2000
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.
Unknown authors · 2000
Researchers exposed mouse m5S cells to power-line frequency magnetic fields at flux densities of 5, 50, and 400 mT for 40 hours. Cells were either untreated or pretreated with mitomycin C or X-rays before exposure. Exposure to 400 mT fields significantly increased chromosomal aberration frequency compared to unexposed controls. The induced aberrations were predominantly chromatid-type, with a three-fold increase at 400 mT. ELFMF exposure also deepened S or G2 arrest after DNA damage.
Preece et al. · 1999
Thirty-six participants completed a randomized three-way crossover study with two training sessions and three test sessions. The only cognitive measure that changed was choice reaction time, which became faster, while word, number, picture recall and spatial memory were unchanged.
Borbely et al. · 1999
Researchers exposed healthy young subjects during an entire night-time sleep episode to a 900 MHz electromagnetic field at a maximum specific absorption rate of 1 W/kg. The exposure schedule consisted of alternating 15-min on-15-min off intervals. Compared with a control night with sham exposure, the amount of waking after sleep onset was reduced from 18 to 12 min, and EEG spectral power in non-rapid eye movement sleep was increased. The researchers concluded that pulsed high-frequency EMF in the range of radiotelephones may promote sleep and modify the sleep EEG.
Unknown authors · 1999
Researchers conducted a case-control study of 399 children with leukemia and 399 controls across five Canadian provinces from 1990 to 1994. Exposure assessment included 48-hour personal EMF measurement, wire coding, residential magnetic field measurements from conception to diagnosis, and 24-hour bedroom magnetic field measurement. Personal magnetic fields were not related to risk of leukemia (adjusted OR = 0.95, p for trend = 0.73) or acute lymphatic leukemia (OR = 0.93, p for trend = 0.64). No clear associations were found with predicted magnetic field exposure two years before diagnosis, over the lifetime, or with personal electric field exposure.
Velizarov, S, Raskmark, P, Kwee, S, · 1999
Researchers exposed cell cultures to a GSM 960 MHz field in a TEM cell at 39°C and 35°C. Exposed cells showed a significant change in proliferation compared to non-exposed controls at both temperatures. Sham-exposed cells showed no significant change in proliferation at either temperature.
Unknown authors · 1999
Unknown authors · 1999
Researchers studied 142 male electric utility workers in Colorado to see how 60 Hz magnetic fields affect melatonin, a hormone that regulates sleep. Workers exposed to temporally stable magnetic fields had reduced levels of melatonin metabolites in their urine, but only when they also had low light exposure at work. This suggests that power line frequency magnetic fields can disrupt the body's natural hormone production.
Goswami PC et al. · 1999
Researchers exposed C3H 10T 1/2 mouse embryo fibroblasts to 835.62 MHz FMCW or 847.74 MHz CDMA microwaves at an average SAR of 0.6 W/kg and measured proto-oncogene expression. The exposures did not alter proto-oncogene expression kinetics after serum stimulation, nor did they change Jun and Myc mRNA levels or AP1, AP2, and NF-kappaB DNA-binding activity during the transition to plateau phase. However, 835.62 MHz FMCW exposure increased Fos mRNA about 2-fold in exponential and plateau-phase cells, and 847.74 MHz CDMA exposure increased it 1.4-fold.
Unknown authors · 1999
HSP70 gene expression is induced by 60-Hz electromagnetic fields. Earlier work showed magnetic field induction occurs at the transcription level through c-myc binding at two nCTCTn sequences at -230 and -160. This study identified a third c-myc binding site between -158 and -162 that regulates magnetic field-induced HSP70 expression. The heat shock element between -180 and -203 is required for magnetic field induction, while the HSE at -100 alone is insufficient.
Unknown authors · 1999
Researchers modeled and measured how 222Rn decay product aerosols behave in the 50 Hz electric field under high voltage power lines to assess increased exposure to airborne pollutants. The model predicted a two- to three-fold increase in aerosol deposition on spherical surfaces mimicking the human head. Experimental measurements using detectors on grounded metal spheres confirmed enhanced deposition of both 218Po and 214Po aerosols. Enhanced 218Po deposition on 400 kV lines ranged from 1.96 to 2.86 times, while 214Po deposition on 275 kV and 132 kV lines was 1.43 and 1.11 times, with the latter not significant.
Unknown authors · 1999
University of Bristol researchers found that high voltage power lines create electric fields that dramatically increase the deposition of airborne pollutants on human skin. Using radioactive marker particles, they measured 2-3 times more pollutant particles depositing on surfaces under 400 kV power lines compared to areas away from the lines. This means people living or working near power lines face significantly higher exposure to whatever air pollution is present.
Unknown authors · 1999
Researchers exposed HL-60 cells to a sinusoidal 0.1 or 1 mT magnetic field at 60 Hz for 2 hours and then pulse-labeled them with radioactive isotopes. In control cultures without magnetic field exposure, the cognate form of stress protein 72c was faintly observed, and 0.1 mT exposure did not alter stress protein metabolism compared to controls. At 1 mT, the inducible form of stress protein 70i was synthesized, stress protein 90 was phosphorylated but not synthesized, and stress protein 27 isoforms a and b were induced. Statistical analysis of Western blot data confirmed a significant increase in stress proteins 90 and 27a after 1 mT exposure.
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.
Fesenko EE, Makar VR, Novoselova EG, Sadovnikov VB. · 1999
Researchers exposed mice to extremely low-level microwave radiation (8.15-18 GHz at just 1 microW/cm²) and found it significantly boosted production of TNF (tumor necrosis factor), a key immune system protein. Short-term exposure for 5 hours to 3 days enhanced immune cell activity, but chronic exposure for 7 days actually suppressed it. This demonstrates that even ultra-weak microwave radiation can measurably alter immune system function in living organisms.
de Seze R, Ayoub J, Peray P, Miro L, Touitou Y · 1999
Researchers evaluated maximum serum melatonin concentration, time of maximum, and area under the curve of the hormone profile. Thirty-eight men aged 20 to 32 years were exposed to GSM 900 or DCS 1800 phones for 2 hr/day, 5 days/wk, for 4 wk at maximum power. Blood samples were collected hourly during the night and every 3 hr in the daytime across four sessions at 15-day intervals. The melatonin circadian profile was not disrupted by the exposure.
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.
Unknown authors · 1999
Researchers exposed human immune cells (mast cells) to microwave radiation at 864.3 MHz for 20 minutes daily over 7 days, using power levels similar to older cell phones. The radiation altered the activity of protein kinase C and changed the expression of three important genes, including one linked to cancer development, even at temperatures too low to cause heat damage.
Unknown authors · 1999
Researchers exposed groups of 100 female Sprague-Dawley rats to 50 Hz magnetic fields at 1 or 5 G, or 60 Hz at 1 G, for 18.5 hours a day, 7 days a week, for 13 weeks after initiating mammary tumors with DMBA. A second study used a lower DMBA dose of 2 mg and exposed rats to 50 Hz fields at 1 or 5 G for the same duration. Magnetic field exposure did not affect body weight, tumor latency, or tumor size in either study, and the authors concluded there was no evidence that 50 or 60 Hz fields promoted breast cancer.
Unknown authors · 1999
Groups of 100 female Sprague–Dawley rats were initiated with a single 10 mg gavage dose of DMBA at 50 days of age and then exposed to ambient fields, 50 Hz magnetic fields at 1 or 5 Gauss, or 60 Hz fields at 1 Gauss for 18.5 hours per day, 7 days per week for 26 weeks. There was no effect of magnetic field exposure on body weight gains or the time of appearance of mammary tumors. Carcinoma incidence was 96%, 90%, 95%, and 85% for the DMBA controls, 1 G 50 Hz, 5 G 50 Hz, and 1 G 60 Hz groups respectively, total carcinoma numbers were 649, 494, 547, and 433 with significant decreases in the 1 G 50 Hz and 1 G 60 Hz groups, and the authors concluded there was no evidence that 50 or 60 Hz magnetic fields promoted breast cancer under the conditions of this assay.
Unknown authors · 1999
Researchers conducted a double-blind laboratory study of 24 healthy young men to examine effects of intermittent versus continuous exposure to a 60 Hz, 28.3 microT magnetic field on EEG measures of night sleep. Intermittent exposure was associated with less total sleep time, reduced sleep efficiency, increased Stage II sleep, and decreased REM sleep, while continuous and sham exposure showed no such effects. Subjects exposed intermittently reported sleeping less well and feeling less rested in the morning compared to the other groups. All observed effects were significant at P < or = .04 or less.
