Trosić I, Pavicić I. · 2009
The study aimed to determine the influence of mobile phone frequency radiation on proliferation, cytoskeleton structure, and mitotic index of V79 cells after 1, 2, and 3 hours of exposure. V79 cells were exposed to continuous-wave 935 MHz radiation at an electric field strength of (8.2+/-0.3) V m(-1) and a specific absorption rate of 0.12 W kg(-1). Cell proliferation declined in cells exposed for three hours when measured 72 hours after irradiation. Microtubule structure was clearly altered immediately after three hours of irradiation. The mitotic index in exposed cells did not differ from negative controls.
Tkalec M et al. · 2009
Researchers exposed Allium cepa seeds for two hours to 400 and 900MHz fields at strengths of 10, 23, 41 and 120Vm(-1), and also tested a four-hour exposure and modulation at 23Vm(-1). Germination rate and root length did not change significantly under any exposure condition. At 900MHz, higher field strengths (41 and 120Vm(-1)) and modulated fields significantly increased the mitotic index, while all 900MHz exposures increased the percentage of mitotic abnormalities. At 400MHz, the mitotic index increased only after modulated exposure, and higher numbers of mitotic abnormalities were found after modulated exposure and after higher field strengths (41 and 120Vm(-1)). The chromosomal aberrations were mainly lagging chromosomes, vagrants, disturbed anaphases and chromosome stickiness.
Sannino A et al. · 2009
Lymphocytes were collected at 72 hours to measure micronuclei frequency in cytokinesis-blocked binucleated cells. Four donors exhibited a significant reduction in micronuclei after RF pre-exposure, indicating an adaptive response. One donor showed no significant difference in micronuclei between pre-exposed and unexposed cells, indicating a non-responder. The data indicated heterogeneity in the induction of an adaptive response between individuals exposed to RF radiation.
Pérez-Castejón C et al. · 2009
Researchers exposed human astrocytoma cells (Clonetics line 1321N1) to a 9.6 GHz carrier wave amplitude-modulated by extremely low frequency pulses in a GTEM cell. The exposure parameters included pulse widths of 100-120 ns, pulse repetition frequencies of 100-800 Hz, power of 0.34-0.60 mW, electric field strength of 1.25-1.64 V/m, and a SAR of 4.0 x 10-4 W/Kg. Cells were exposed for 15, 30, 60 minutes, and 24 hours using a double-blind method with sham controls. Cytoskeleton proteins, cell morphology, and viability were unchanged, but cell proliferation rate increased significantly after 24 hours of exposure. Hsp-70 and Bcl-2 antiapoptotic proteins were present in both control and exposed samples, while connexin 43 protein expression increased in exposed samples.
Moisescu MG, Leveque P, Verjus MA, Kovacs E, Mir LM. · 2009
The exposure increased Lucifer Yellow uptake, and this increase was not due to heating. Chlorpromazine and ethanol blocked the increase while Filipin did not, indicating involvement of clathrin-coated vesicles.
Li X et al. · 2009
Researchers exposed 70 male rats to microwave radiation at average power densities of 0, 10, 30, and 100 mW/cm(2). Rats were sacrificed at 6 hours, 1 day, 3 days, and 7 days after exposure. Protein levels of AQP4 increased initially and then recovered at 10 and 30 mW/cm(2), but increased progressively at 100 mW/cm(2) within 14 days. Gene expression of AQP4 increased at 6 hours after 10 mW/cm(2) exposure and returned to baseline, while at 30 and 100 mW/cm(2) it peaked at 7 days and did not return.
Kundi M, Hutter HP. · 2009
Cross-sectional investigations of subjective health as a function of distance or measured field strength found indications for an effect of exposure that is likely independent of concerns and attributions. Experimental studies applying short-term exposure to base station signals gave various results, but there is weak evidence that UMTS and to a lesser degree GSM signals reduce wellbeing in persons that report to be sensitive to such exposures. Two ecological studies of cancer near base stations reported a strong increase in incidence within 350 and 400 meters, but limitations prevent firm conclusions.
Gao XF et al. · 2009
Researchers established a model of primary cultured Sertoli cells in vitro and exposed them to microwave radiation at average power densities of 0, 30, and 100 mW/cm(2) for five minutes. Cell cycle distribution shifted at exposure to 30 mW/cm(2) compared with the control groups, but the changes of rate of apoptosis and death and intracellular Ca2+ concentration showed no difference at 6 h after exposure. At 6 h after exposure to 100 mW/cm(2) microwave, there was a significant increase in intracellular Ca2+ concentration and rate of apoptosis and death, and the researchers identified the increase of intracellular Ca2+ concentration as one of the injury mechanisms.
Gao XF,Pei LP, Chen CH, Yang XS, Zhang GB, Deng ZH, Yu ZP. · 2009
Researchers exposed rats to whole-body microwave irradiation at 90 and 5 W/cm² for 20 minutes and measured changes in HSP70 in the hippocampus. Both mRNA and protein expression of HSP70 in the rat hippocampus increased after the exposures. Anal temperature and SAR values also increased significantly, and these changes were positively correlated with power and irradiation time.
Frei P et al. · 2009
Researchers measured RF-EMF exposure of 166 volunteers from Basel, Switzerland, using personal exposure meters carried for one week. Mean weekly exposure across all RF-EMF sources was 0.13 mW/m2, ranging across individuals from 0.014 to 0.881 mW/m2. Exposure varied considerably between persons and locations but was fairly consistent within persons.
Dimbylow PJ, Nagaoka T, Xu XG. · 2009
The study compared foetal specific absorption rate (SAR) across three sets of pregnant female computational models. The models included a 26-week foetal model from the National Institute of Information and Communications Technology, Tokyo, and models at 13, 26, and 38 weeks from Rensselaer Polytechnic Institute. FDTD calculations were performed at a resolution of 2 mm for a plane wave with a vertically aligned electric field incident upon the body from the front, back and two sides from 20 MHz to 3 GHz under isolated conditions. The researchers compared external electric field values required to produce the ICNIRP public exposure localized restriction of 2 W kg(-1) when averaged over 10 g of the foetus with the ICNIRP reference levels.
Cao Y, Xu Q, Lu MX, Jin ZD, DU HB, Li JX, Nie JH, Tong J. · 2009
Researchers treated male Kunning mice with low-dose microwave radiation before exposing them to gamma-ray irradiation, then measured survival, blood parameters, and markers of bone marrow activity. Mice pre-exposed to 120 microW/cm² 900 MHz microwave had a higher 30-day survival rate and more white blood cells compared with gamma-ray-treated mice that did not receive microwave pre-exposure. The microwave pre-exposure group also showed increases in thymus and spleen organ indexes, bone marrow cell proliferation activity, CFU-GM hematopoietic foci numbers, and serum concentrations of GM-CSF and IL-3. The researchers suggested that low-dose microwave radiation may exert potential antagonistic effects on hematopoietic injuries induced by ionizing radiation.
Brescia F et al. · 2009
Researchers measured reactive oxygen species (ROS) production in human lymphoblastoid cells exposed to a 1950 MHz UMTS signal at Specific Absorption Rates of 0.5 and 2.0 W/kg. Exposures ranged from short durations of 5 to 60 minutes up to 24 hours, and the study also tested RF radiation given before or at the same time as ferrous ions. RF exposure did not increase ROS formation or affect cell viability, and combining RF with ferrous ions did not produce more ROS than ferrous ions alone.
Aweda MA et al. · 2009
Researchers measured radiofrequency radiation output power densities from commonly used GSM handsets and wireless phones across Lagos State, Nigeria. Over 1100 handsets of different makes and models as well as wireless phones were sampled across all local government areas of the state. GSM handset power density values ranged from a minimum of 1.294 Wm-2 with Siemens model R228 to a maximum of 16.813 Wm-2 with Samsung model C140. The study concluded that the population in Lagos State may be at risk due to significant radiofrequency radiation exposures from GSM use.
Augner C, Florian M, Pauser G, Oberfeld G, Hacker GW. · 2009
Researchers examined the effects of short-term GSM base station radiofrequency electromagnetic field exposure on psychological symptoms including good mood, alertness, and calmness, as measured by a standardized well-being questionnaire. Fifty-seven participants were randomly assigned to one of three different exposure scenarios, each involving five 50-min exposure sessions. Participants in the high and medium exposure scenarios were significantly calmer than those in the low-exposure scenario (P = 0.042), though no significant differences were found for good mood or alertness. The researchers concluded that short-term exposure to GSM base station signals may have an impact on well-being by reducing psychological arousal.
Amoako JK, Fletcher JJ, Darko EO. · 2009
Researchers surveyed radiofrequency electromagnetic radiation at public access points near cellular phone base stations operated by the Ghana Telecommunications Company. Measurements were made using a hand-held spectrum analyser to determine electric field levels within the 900 and 1800 MHz frequency bands. Power densities at public access points ranged from 0.01 to 10 microW m(-2) at 900 MHz, and from 0.01 to 100 microW m(-2) at 1800 MHz. The results were within international guidance levels but were 20 times higher than results generally obtained for such a practice elsewhere.
Reba Goodman et al. · 2009
Researchers used regenerating planaria Dugesia dorotocethala as a model to determine whether an intermittent modulated extremely low frequency electromagnetic field produces elevated levels of hsp70 and stimulates intracellular pathways known to be involved in injury and repair. Individual head and tail portions from the same worm were exposed to a 60 Hertz 80 milliGauss ELF-EMF for 1 h twice daily for 15 days post-transection. ELF-EMF exposure caused a significant increase in regeneration for both heads and tails, and exposed tails developed eyes at day seven post-transection, while sham control tails showed the first appearance of eyes 48 h later. Exposed animals also showed an elevation in hsp70 protein, an activation of an ERK cascade, and an increase in SRF-SRE binding.
Amara S et al. · 2009
Researchers exposed male rats to a static magnetic field at 128 mT for one hour per day over 30 consecutive days and then measured antioxidant enzyme activity, malondialdehyde concentration, and DNA oxidation in the brain. In the frontal cortex, exposure decreased glutathione peroxidase activity by 39%, CuZn superoxide dismutase activity by 35%, and catalase activity by 59%. In the hippocampus, exposure decreased CuZn-SOD activity by 51% and Mn-SOD activity by 13%, and increased malondialdehyde concentration by 32%. DNA oxidation was not detected, and the researchers suggested that an increase in metallothioneins in the frontal cortex may have protected DNA from oxidative damage.
Sharma VP, Singh HP, Kohli RK, Batish DR. · 2009
Researchers exposed mung bean (Vigna radiata) seeds to cell phone EMF radiation at a power density of 8.55 microW cm(-2) in the 900 MHz band for durations of 1/2, 1, 2, and 4 hours. Cell phone EMF radiation significantly inhibited germination at exposures of 2 hours or more, and inhibited radicle and plumule growth at 1 hour or more, in a time-dependent manner. The radiation enhanced MDA content, increased hydrogen peroxide accumulation, and raised root oxidizability, indicating oxidative stress and cellular damage. The study concluded that cell phone EMF radiation inhibits root growth by inducing oxidative stress despite increased activities of antioxidant enzymes.
Sharifian A, Gharavi M, Pasalar P, Aminian O · 2009
Researchers measured antioxidant markers in 46 spot welders occupationally exposed to extremely low frequency magnetic fields and compared results with a non-exposed control group. In the red blood cells of exposed workers, SOD activity decreased by 22% and GPX activity decreased by 12.3%, both statistically significant. Total serum antioxidant status showed no significant difference between the two groups. The researchers concluded that ELF-MF could influence red blood cell antioxidant activity and might act as an oxidative stressor.
Henrykowska G et al. · 2009
Researchers exposed human blood platelet suspensions for 15 minutes to a 50 Hz magnetic field of different shapes at a flux density of 10 mT. The study measured catalase and superoxide dismutase activity, malondialdehyde concentration, and free radical generation in human blood platelets. Free radicals, malondialdehyde, and catalase all showed increased values compared with the initial level regardless of field shape, while superoxide dismutase activity was lower than at the onset of the experiment.
Ciejka EB, Goraca A · 2009
The study tested whether a time-variable magnetic field affects heart rate and plasma antioxidant capacity. Tests were performed on Sprague-Dawley rats exposed to the magnetic field at a frequency of 40 Hz and induction of 7 mT for 30 and 60 minutes. A significant decrease of the heart rate was observed after 14 days of exposure. Exposure at 60 minutes for 14 days caused a significant decrease of the organism antioxidant defence.
Varró P, Szemerszky R, Bárdos G, Világi I. · 2009
Researchers exposed whole rats or excised rat brain slices to a 50 Hz electromagnetic field at 250–500 µT to examine effects on synaptic efficacy in the central nervous system. Slices treated directly ex vivo showed a decrease in basic synaptic activity, observed as a diminution in amplitude of evoked potentials. Following whole-body exposure, enhanced short- and long-term synaptic facilitation in hippocampal slices and increased seizure susceptibility in neocortical slices were observed. The researchers noted that the overall changes may strongly depend on the synaptic structure and neuronal network of the affected region, together with the specific spatial parameters and constancy of the EMF.
Strasák L, Bártová E, Krejci J, Fojt L, Vetterl V. · 2009
Researchers exposed female and male laboratory mice for 4 days to a 50 Hz magnetic field at 2 mT inside a cylindrical coil. After exposure, levels of the proteins c-Jun and c-Fos in different parts of the brain were measured using Western-blot techniques. The expression of c-Jun decreased after magnetic field exposure, while c-Fos expression was not affected, and neither result depended on the sex of the mice.
Janać B, Tovilović G, Tomić M, Prolić Z, Radenović L. · 2009
Researchers exposed adult Wistar rats continuously to an extremely low frequency magnetic field (50 Hz, 0.5 mT) for 1, 3, and 7 days. The study examined serotonin 5-HT(2A) receptors in the prefrontal cortex and dopamine D(1) and D(2) receptors in the striatum, considering their involvement in motor behavior regulation. Serotonin 5-HT(2A) receptor affinity decreased and density increased in the prefrontal cortex, with the affinity effect being most prominent after 7 days of exposure. Dopamine D(1) and D(2) receptors in the striatum showed no significant effect on either affinity or density.
