Fernie KJ, Bird DM. · 2001
Researchers investigated whether exposure to magnetic and electric fields similar to those from power lines induces an immune response and alters oxidative stress levels in American kestrels. Captive male kestrels were bred under control or EMF conditions equivalent to those experienced by wild kestrels. Short-term EMF exposure suppressed plasma total proteins, hematocrits, and carotenoids in the first half of the breeding season, and also suppressed erythrocyte cells and lymphocyte proportions while elevating granulosa proportions at the end of the breeding season. Long-term EMF exposure may be linked to higher levels of oxidative stress through EMF exposure only, and also suppressed hematocrits in the first half of the reproductive period.
Unknown authors · 2000
The researchers studied the effect of extremely low frequency electromagnetic fields combined with mild heat shock on reporter gene expression in two transgenic strains of Caenorhabditis elegans. Reporter gene expression was measured by scoring animals with induced beta-galactosidase activity after staining in toto or by biochemical quantitation of enzyme activity. They defined experimental conditions where electromagnetic fields strongly enhanced the expression of the reporter gene.
Unknown authors · 2000
Researchers examined the effect of 50 mT, 60 Hz ELFMF on heat-induced HSP-70 expression in HL60RG cells. Exposure to 50 mT ELFMF alone did not increase HSP-70 production. Combined exposure to 50 mT ELFMF and mild heat at 40°C and 42°C suppressed heat-induced HSP-70 expression. This suppression required simultaneous exposure for more than 5 hours. Lower magnetic densities of 5 mT and 0.5 mT did not suppress HSP-70.
Yoshikawa T et al. · 2000
Lourencini da Silva R et al. · 2000
Researchers exposed SnCl2-treated pBR322 plasmids to EMF and analyzed conformational changes using agarose gel electrophoresis. EMF exposure increased DNA scission, seen as relaxed plasmids. Plasmids pre-exposed to EMF were less able to transform E. coli. The authors concluded that EMF in the presence of a transition metal can cause DNA damage.
Laurence JA, French PW, Lindner RA, Mckenzie DR · 2000
The aim was to investigate mechanisms for the effects of pulsed microwave radiation on protein conformation. The researchers modeled heat diffusion and showed that pulsed exposure can cause transient temperature excursions outside the normal range even when athermal. They propose that the power window phenomenon may be caused by incomplete triggering of the heat shock response.
Kalns J, Ryan KL, Mason PA, Bruno JG, Gooden R, Kiel JL. · 2000
Brezitskaia HV, Timchenko OI · 2000
The study aimed to observe the mechanism of cytogenetic effect of electromagnetic radiation and the role of oxidation homeostasis. Changes in oxidation homeostasis preceded development of cytogenetic effects and could be their reason.
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.'
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.
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.
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.
Khadir R, Morgan JL, Murray JJ. · 1999
Researchers investigated the effects of a sinusoidal 60 Hz magnetic field on free radical production, degranulation, and viability in human neutrophils. Exposure of unstimulated human neutrophils to the magnetic field did not affect the functions examined. When cells were also stimulated with PMA, exposure to a 22 mT, 60 Hz magnetic field induced significant increases in superoxide anion production of 26.5% and in β-glucuronidase release of 53%. Release of lysozyme and lactate dehydrogenase was unchanged by the magnetic field, whether the cells were stimulated or not.
Unknown authors · 1998
Unknown authors · 1998
Researchers examined the separate and combined effects of 60 Hz magnetic fields and a phorbol ester on PKC activity in HL60 cells. Exposure to a 1.1 mT magnetic field alone or combined with 2 microM PMA for 1 h did not enhance PKC activity. In a second experiment, cells preexposed to 50 nM PMA for 45 min then exposed to both PMA and magnetic field for 15 min showed a greater decrease in cytosolic PKC activity and a larger increase in membrane activity than PMA treatment alone or PMA with sham exposure. The authors concluded that magnetic fields may act synergistically on an already activated pathway.
Daniells et al. · 1998
Researchers used transgenic Caenorhabditis elegans strain PC72 carrying a heat-shock promoter driving a beta-galactosidase reporter gene. The nematodes were exposed in a transverse electromagnetic cell at 750 MHz and 27 dBm, with the cell held at 25°C in a shielded incubator. Significant stress responses were observed at 2 and 16 hours but not at 4 or 8 hours. Lower power levels of 21 dBm produced greater responses than 27 dBm at both 750 and 300 MHz, a pattern opposite to that expected from simple heating. In a 5 x 5 multiwell plate, wells in rows nearest the exposure showed the strongest response, while the most distant row did not rise above control levels, suggesting a shadow effect.
Unknown authors · 1997
Unknown authors · 1997
The authors conducted a literature study comparing skin changes in screen dermatitis with those from UV light or ionizing radiation. Screen dermatitis patients had a much higher number of mast cells. The most remarkable cellular change was the disappearance of Langerhans cells, which also occurs after UV or ionizing radiation.
Koldayev VM, Shchepin YV, · 1997
The aim of the study was to investigate effects of electromagnetic radiation on sea-urchin embryos. Electromagnetic radiation caused a decrease in the number of fertilized eggs and an increase in the number of zygotes with abnormal fertilization envelopes in sea-urchins.
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.
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.
Lai H, Singh NP · 1997
Researchers investigated whether melatonin and the spin-trap compound N-tert-butyl-alpha-phenylnitrone (PBN) could block the effect of magnetic fields on brain cell DNA. Rats were injected with melatonin or PBN immediately before and after two hours of exposure to a 60-Hz magnetic field at an intensity of 0.5 mT. Both drug treatments blocked the magnetic field-induced DNA single- and double-strand breaks in brain cells, as measured by a microgel electrophoresis method.
Fiorani M et al. · 1997
Researchers investigated the effects of 50 Hz magnetic fields (0.2–0.5 mT) on rabbit red blood cells exposed at the same time to an oxygen radical-generating system, Fe(II)/ascorbate. A 0.5 mT magnetic field had no effect on intact red blood cells, but when cells were already under oxidative stress, exposure caused a significant further decay in hexokinase activity of about 20% and a twofold increase in methemoglobin production. The researchers concluded that the magnetic fields studied were able to potentiate the cellular damage induced in vitro by oxidizing agents.
Balodis V, G Briimelis, K Kalviskis, et al. · 1996
Dr Cherry was invited by the New Zealand Ministry of Health and Ministry for the Environment to peer-review the proposal to adopt the ICNIRP guidelines for cell sites in November 1999. The review found that the ICNIRP assessment ignored all published studies showing chromosome damage and was highly selective, biased, and dismissive of genotoxic and epidemiological evidence. The assessment gave the impression of being predetermined to accept only effects from high exposures causing electric shocks or tissue heating, and it misrepresented two studies that actually showed significant increases in brain/CNS cancer.
Roy S et al. · 1995
Researchers investigated whether a low-frequency, low-intensity magnetic field could affect the oxidative burst triggered by PMA in rat peritoneal neutrophils. In the presence of the magnetic field, a 12.4% increase in the fluorescence signal was observed in PMA-stimulated neutrophils (n = 5, P < 0.02, 18 pairs of measurements). The researchers described this as what they believed to be the first experimental observation of a magnetic field influencing free radical species generated during signal transduction in living cells.
