Eşmekaya MA, Seyhan N, Omeroğlu S. · 2010
Researchers exposed two-month-old male Wistar rats to 900 MHz pulse-modulated RF radiation at a SAR of 1.35 Watt/kg for 20 min/day for three weeks. The study examined thyroid gland tissue using light microscopy, electron microscopy, and immunohistochemical methods. Morphological analyses revealed hypothyrophy of the gland, and the results indicated that thyroid hormone secretion was inhibited by the RF radiation. Apoptotic bodies were observed, and caspase-3 and caspase-9 activities were increased in thyroid cells of exposed rats.
Zhijian C et al. · 2010
Researchers used a comet assay to study whether 1.8-GHz radiofrequency radiation (RFR, SAR of 2 W/kg) could influence DNA repair in human B-cell lymphoblastoid cells exposed to doxorubicin (DOX). RFR alone did not directly induce DNA damage in the cells. A specific combined-exposure pattern could obviously influence DNA repair at 6 h and 12 h after exposure to DOX for four DOX doses.
Kesari KK, Behari J. · 2010
Sperm GPx and SOD activity showed a significant decrease in exposed rats, while catalase showed a significant increase compared with the control group. The percentage of apoptosis was higher in the exposed group, and significant decreases were found in the S phase and G2/M transition phase of the cell cycle. The researchers concluded that these radiations may have a significant effect on the reproductive system of male rats, which may be an indication of male infertility.
Achudume A, Onibere B, Aina F, Tchokossa P · 2010
Researchers exposed male Wistar rats to radio frequency radiation at 1800 MHz with a specific absorption rate of 0.95 to 3.9 W/kg for 40 or 60 days continuously. At 40 days, electromagnetic radiation failed to induce any significant alterations. At 60 days of exposure, various attributes evaluated decreased, including decreases in NADPH and ascorbate-linked lipid peroxidation along with diminution in enzymatic antioxidative defense systems and decreased glucose residue.
Maskey D et al. · 2010
Researchers investigated the effect of 835-MHz radiofrequency exposure on rat hippocampus for 3 months using immunohistochemical methods. A decrease in calbindin immunoreactivity was observed in the exposed group, with loss of interneurons and pyramidal cells in the CA1 area and loss of granule cells. An overall increase in GFAP immunoreactivity was observed in the hippocampus of exposed rats, and apoptotic cells were detected in the CA1, CA3 areas and dentate gyrus.
Maskey D et al. · 2010
Researchers measured calbindin (CB) and calretinin (CR) expression in the hippocampus of mice after exposure to 835 MHz electromagnetic fields at various durations and absorption rates. Exposure conditions included 1 hour per day for 5 days at a specific absorption rate of 1.6 W/kg, 1 hour per day for 5 days at 4.0 W/kg, 5 hours per day for 1 day at 1.6 W/kg, 5 hours per day for 1 day at 4.0 W/kg, and daily exposure for 1 month at 1.6 W/kg. Exposure for 1 month produced almost complete loss of pyramidal cells in the CA1 area. Body weights did not change significantly across the exposure groups.
Hao Y, Yang X, Chen C, Yuan-Wang, Wang X, Li M, Yu Z · 2010
Researchers exposed murine N9 microglial cells to 2.45 GHz electromagnetic fields and examined several molecular markers of cell activation. After exposure, a significant increase of STAT3 DNA-binding ability was noted, and EMF rapidly induced phosphorylation of STAT3 and activated JAK1 and JAK2. Transcription levels of the inflammation-associated genes iNOS and TNF-alpha also increased after EMF exposure. When a JAK inhibitor called P6 was applied, it reduced induction of iNOS and TNF-alpha, nuclear factor binding activity, and activation of STAT3 in EMF-stimulated microglia.
Kumar S, Kesari KK, Behari J. · 2010
Wistar rats were exposed to microwaves for 2 hours a day for 45 days at either 10 GHz or 50 GHz, and blood cells and serum were then analyzed. The exposed rats showed micronuclei formation and a significant increase in ROS production, along with significant changes in glutathione peroxidase, superoxide dismutase, and catalase levels. The researchers concluded that microwave exposure may be effective at the genetic level and suggested this may indicate tumor promotion through overproduction of reactive oxygen species.
Ziemann C et al. · 2009
Researchers exposed male and female B6C3F1 mice to GSM 902 MHz and DCS 1747 MHz signals for two years. The exposure regimen was 2 hours per day, 5 days per week, at whole-body averaged SARs of 0.4, 1.3, and 4.0 W/kg. Micronuclei were counted in peripheral blood erythrocytes stained with May-Grunwald-Giemsa or acridine orange. No significant differences in micronuclei frequency were observed between RF-exposed, sham-exposed, and cage control mice. Positive control mice injected with mitomycin C had significantly increased micronuclei, and the authors concluded that the data did not indicate RF-induced genotoxicity after two years.
Hansteen IL et al. · 2009
The aim was to test if exposure used in mobile phones and wireless network technologies would induce DNA damage in cultured human lymphocytes with and without a known clastogen. Lymphocytes from six donors were exposed to 2.3 GHz, 10 W/m(2) continuous waves, or 2.3 GHz, 10 W/m(2) pulsed waves (200 Hz pulse frequency, 50% duty cycle). Mitomycin C was added to half of the cultures. No statistically significant differences were observed between control and exposed cultures. A weak trend for more chromosomal damage with the interaction of pulsed fields with mitomycin C compared to a constant field was observed.
Hansteen IL et al. · 2009
Researchers exposed lymphocytes from two smoking and four non-smoking donors for 53 hours to 1.0 W/m(2) continuous-wave at 18.0 GHz or 10 W/m(2) pulsed-wave at 16.5 GHz, alone or with MMC. DNA synthesis and repair were inhibited in some cultures. No synergistic effect was observed with MMC or with cells pre-exposed to tobacco smoke. A non-significant trend toward increased aberration frequencies appeared for 16.5 GHz pulsed exposure in DNA synthesis and repair inhibited cultures. Neither exposure induced statistically significant increases in chromosomal aberration frequencies.
Sannino A et al. · 2009
Researchers exposed human dermal fibroblasts from a healthy donor and a Turner's syndrome donor to 900 MHz RF radiation for 24 hours using a GSM-like signal at 1 W/kg, and Turner's syndrome fibroblasts were also exposed for 1 hour. For RF exposure alone, DNA damage was assessed with the alkaline comet assay and the cytokinesis-block micronucleus assay. RF radiation alone caused no genotoxic or cytotoxic effects in either cell line. MX increased DNA migration in the comet assay, but RF exposure did not enhance this MX-induced DNA damage.
Finnie JW, Blumbergs PC, Cai Z, Manavis J · 2009
Researchers exposed mice to 900 MHz radiofrequency fields at a specific absorption rate of 4 W/kg for 60 minutes or for 5 days per week over 104 weeks. Control mice were sham-exposed or freely moving to account for restraint stress, and a positive control group received a clostridial toxin that upregulates aquaporin-4. No immunohistochemically detectable up-regulation of aquaporin-4 was observed in exposed mouse brains after either short or long exposure durations.
Mousavy SJ et al. · 2009
Researchers investigated the effect of mobile phone RF (910 MHz and 940 MHz) on the structure and function of HbA. Oxygen affinity was measured using sodium dithionite with a UV-vis spectrophotometer, and structural changes were studied by circular dichroism and fluorescence spectroscopy. The results indicated that mobile phone EMFs altered oxygen affinity and tertiary structure of HbA. Furthermore, the decrease of oxygen affinity of HbA corresponded to the EMFs intensity and time of exposure.
Gul A, Celebi H, Uğraş S. · 2009
Researchers exposed pregnant rats to mobile phones during pregnancy and examined ovarian follicles in their female offspring at 21 days old. The study group had fewer ovarian follicles than the control group. The authors suggest that intrauterine microwave exposure has toxic effects on ovaries.
Atay T et al. · 2009
Researchers investigated the effects of electromagnetic waves from cellular phones operating at 900 to 1800 MHz on bone mineral density of the human iliac bone wings in 150 male volunteers. Participants were divided into two groups based on the iliac side exposed to electromagnetic waves (group 1) and the unexposed side (group 2). The mean daily phone carriage duration was 14.7 hours and the mean duration of phone use was 6.2 years. Dual-energy x-ray absorptiometry measurements showed slightly lower values on the exposed side but the difference was not statistically significant (P > 0.05), and values were not as low as in osteopenia or osteoporosis.
Anghileri LJ, Mayayo E, Domingo JL. · 2009
The study found a synergism between aluminum and radiofrequency that increased early mortality in lymphoma-bearing mice. This synergism was stronger with aluminum lactate than with aluminum citrate due to higher ionization at physiological pH. The dissociation of aluminum complexes appears to induce a remarkable acceleration of mortality and lymphoid-related hypertrophy of the spleen and liver at an early age. Calcium chloride overload had no effect when cellular calcium homeostasis was functional. The researchers measured organ hypertrophy using the organ-to-body-weight ratio and histopathological examination.
Zareen N, Khan MY, Ali Minhas L · 2009
Embryos exposed for 10 post-incubation days showed decreased retinal growth and mild epithelial pigmentation. Extending exposure to 15 post-incubation days reversed growth retardation to enhancement and shifted pigmentation from mild to intense. The authors concluded that mobile phone EMF causes derangement of chicken embryo retinal differentiation. Retinal thickness and epithelial pigmentation grades were statistically compared between control and experimental groups.
Vácha M, Puzová T, Kvícalová M · 2009
Researchers tested how weak radio frequency magnetic fields affect the American cockroach's ability to sense the geomagnetic field. A 1.2 MHz field disrupted this sense at intensities between 12 nT and 18 nT, while a 2.4 MHz field required between 18 nT and 44 nT. A 7 MHz field had no effect even at the highest tested intensity of 44 nT. The disruptive effect was strongest at the Larmor frequency of 1.2 MHz. The researchers measured the rise in locomotor activity induced by periodic changes in the geomagnetic North position by 60 degrees.
Zhijian C et al. · 2009
Researchers used the in vitro comet assay to determine whether 1.8-GHz radiofrequency radiation can influence DNA repair in human leukocytes exposed to X-rays. Leukocytes from four young healthy donors were intermittently exposed to RFR at a SAR of 2 W/kg for 24 hours with fields on for 5 minutes and off for 10 minutes, then irradiated with X-rays at doses of 0.25, 0.5, 1.0 and 2.0 Gy. DNA damage was measured at 0, 15, 45, 90, 150 and 240 minutes after X-rays using percent tail DNA, and repair speed was assessed via DNA repair percentage. The results showed individual differences in DNA repair speeds among the four donors. Intermittent RFR exposure did not directly induce DNA damage or show synergistic effects with X-rays.
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.
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.
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.