Tanvir S et al. · 2016
Researchers exposed human CPR to 1966-MHz RF for 60 minutes using a TEM cell in an incubator at a specific absorption rate (SAR) of 5W·kg(-1). The Michaelis Menten constant (Km) and maximum initial velocity (Vmax) decreased by 22% compared with controls. Conformational changes were detected via fluorescent spectroscopy of flavin and tryptophan residues and investigated with circular dichroism, dynamic light scattering, and microelectrophoresis.
Liu YX et al. · 2015
Researchers exposed human glioblastoma cell lines U251-MG and U87-MG to 1950-MHz TD-SCDMA fields at a maximum SAR of 5.0 W/kg for 12, 24, and 48 hours. They measured cell morphology, apoptosis, cell cycle, growth, gene and protein expression, tumor formation, and invasiveness. No significant differences in biological features or tumor formation ability were found between exposed and unexposed cells. Exposure did not act as a cytotoxic or tumor-promoting agent affecting proliferation or gene expression.
Luukkonen J, Juutilainen J, Naarala J. · 2010
Researchers aimed to investigate cooperative effects of 872 MHz RF radiation and ferrous chloride on ROS production and DNA damage in human neuroblastoma SH-SY5Y cells. They exposed the cells to 872 MHz RF radiation at 5 W/kg SAR using continuous wave or GSM-like modulated signals for 1 hour in ROS experiments and 3 hours in comet assay experiments. Chemical treatments with ferrous chloride produced statistically significant responses, but RF radiation alone or combined with chemicals did not affect ROS production, DNA damage, or cell viability.
Luukkonen J et al. · 2009
Researchers exposed human SH-SY5Y neuroblastoma cells to 872 MHz radiofrequency radiation at 5 W/kg for 1 hour, combined with menadione, a chemical that induces intracellular ROS production and DNA damage. Continuous-wave RF radiation increased DNA breakage compared to cells exposed only to menadione, and ROS levels were higher at 30 and 60 minutes after exposure ended. No effects of the GSM signal were seen on either ROS production or DNA damage.
Höytö A, Luukkonen J, Juutilainen J, Naarala J. · 2008
Researchers exposed human SH-SY5Y neuroblastoma and mouse L929 fibroblast cells to 872 MHz radiofrequency radiation at a specific absorption rate of 5 W/kg, using either continuous waves or a GSM-modulated signal. Two statistically significant differences related to RF radiation were found: t-BOOH-induced lipid peroxidation was increased in SH-SY5Y cells, and menadione-induced caspase 3 activity was increased in L929 cells, but both only for the GSM-modulated signal. No other endpoints were significantly affected, and no effects were observed from RF radiation exposure alone.
Vanderwaal RP, Cha B, Moros EG, Roti Roti JL. · 2006
The radiofrequency exposures were 847 MHz TDMA at a SAR of 5 W kg-1 for 1, 2, or 24 h and 900 MHz GSM at a SAR of 3.7 W kg-1 for 1, 2, or 5 h. Acute hyperthermia at 45 degrees C increased the proportion of higher phosphorylated forms of HSP27. Exposure of HeLa S3 cells to 5 W kg-1 TDMA for 1, 2, or 24 h did not induce significant differences in HSP27 phosphorylation compared to incubator control or sham.
Whitehead TD, Moros EG, Brownstein BH, Roti Roti JL · 2006
Researchers performed in vitro experiments with C3H 10T(1/2) mouse cells to test whether FDMA or CDMA modulated RF radiation induces changes in gene expression. Cells were exposed to either modulation for 24 h at a specific absorption rate (SAR) of 5 W/ kg. Gene expression was evaluated using the Affymetrix U74Av2 GeneChip to detect changes in mRNA levels. As a positive control, cells were exposed to 0.68 Gy of X rays and gene expression was evaluated 4 h after exposure. For both CDMA and FDMA radiation, the number of probe sets with expression changes greater than 1.3-fold was less than or equal to the expected false positives, indicating no statistically significant effect on gene expression.
Masuda H et al. · 2006
Researchers exposed hairless female rats to GSM-900 or -1800 signals for 2 hours using a loop antenna on the back. The local specific absorption rate at skin level was about 5 W/kg. Skin thickness and cell toxicity did not differ between exposed and sham-exposed rats. Cell proliferation in the epidermis remained within normal range and no proliferation was seen in the dermis. Levels of filaggrin, collagen, and elastin were not significantly affected by the exposure.
Whitehead TD, Moros EG, Brownstein BH, Roti Roti JL. · 2006
Researchers exposed cultured C3H 10T 1/2 cells to cell phone RF radiation at a specific absorption rate of 5 W/kg for 24 hours. Gene expression was measured using Affymetrix microarrays and compared to sham controls. The RF exposure did not produce more gene expression changes than expected by chance. In contrast, X-ray exposure at 0.68 Gy with a 4-hour recovery produced more changes than the sham comparison.
Whitehead TD et al. · 2005
The study aimed to confirm a previous report that CDMA and FDMA radiation increased Fos levels as cells entered plateau phase. Fos mRNA levels were not significantly different from sham exposure at either SAR level for any signal modulation. Therefore, the earlier results could not be confirmed.
Komatsubara Y et al. · 2005
Researchers exposed murine m5S cells to 2.45 GHz high-frequency electromagnetic fields for 2 hours at SARs of 5, 10, 20, 50, and 100 W/kg continuous wave and at a mean SAR of 100 W/kg pulse wave with a maximum of 900 W/kg. The effects were compared with sham-exposed controls and with mitomycin C and X-ray treatments as positive controls. No significant differences in chromosomal aberrations were observed between HFEMF-exposed cells and sham controls, while positive controls increased chromatid-type and chromosome-type aberrations.
Wang J et al. · 2005
Researchers exposed mouse C3H10T1/2 cells to 2450 MHz HFEMF at SARs of 5 to 200 W/kg for 2 hours, with or without methylcholanthrene (MC) and the tumor promoter TPA. Transformed foci of Type II and Type III were counted as the endpoint. No significant differences were observed in malignant transformation frequency between controls and HFEMF with or without TPA. Transformation frequency increased for HFEMF at SAR above 100 W/kg when combined with MC or MC plus TPA, while heat exposure did not increase transformation.
Koyama S, Isozumi Y, Suzuki Y, Taki M, Miyakoshi J. · 2004
Researchers exposed Chinese hamster ovary CHO-K1 cells to 2.45-GHz electromagnetic fields for 2 hours at SARs of 5, 10, 20, 50, 100, and 200 W/kg to study micronucleus formation. Micronucleus frequency in cells exposed at SARs lower than 50 W/kg did not differ from sham-exposed controls. At SARs of 100 and 200 W/kg, micronucleus frequency was significantly higher than in sham-exposed controls. The researchers also found that micronucleus frequency increased in a temperature-dependent manner when cells were heat-treated at temperatures from 38 to 42 degrees C.
d'Ambrosio G, MassaR, Scarfi MR, Zeni O · 2002
Researchers exposed human peripheral blood cultures to 1.748 GHz microwaves, either as continuous wave or phase-only modulated wave, for 15 minutes. The study measured cell proliferation kinetics and micronucleus frequency to look for genotoxic effects. No changes in cell proliferation kinetics were found after either type of exposure. A statistically significant micronucleus effect was found following exposure to the phase modulated field, but not after continuous wave exposure. The researchers suggested these results indicate a genotoxic power of the phase modulation itself.
Cao G, Liu LM, Cleary SF · 1995
Researchers exposed synchronized Chinese hamster ovary (CHO) cells to 27 MHz continuous-wave radio-frequency radiation for 2 hours at specific absorption rates of 5 or 25 W kg−1 under isothermal conditions, meaning no heating occurred. The exposure produced time- and dose-rate-dependent cell cycle alterations, with maximum responses occurring 3 days after exposure at a SAR of 25 W kg−1. Cells in G0/G1- or S-phase showed more pronounced alterations, while G2/M-phase cells showed minimal effects at either SAR.
Conover DL et al. · 1992
Researchers measured foot currents in workers who stood at their normal operating positions near industrial dielectric heaters generating fields at frequencies from 6.5 to 65 MHz. Nearly 27 percent of the heaters induced foot currents exceeding the proposed 200-mA ANSI C95.1 limit, and 20 percent exceeded 350 mA. Specific absorption rates in ankles were calculated from foot currents and approximated 5 W/kg at 100 mA, 29 W/kg at 250 mA, and 57 W/kg at 350 mA, with a maximum of approximately 176 W/kg at 617 mA.
Lu ST et al. · 2010
Researchers exposed four adult male Rhesus monkeys to a 2.8 GHz pulsed microwave signal at 13.0 mW/cm(2) spatial and temporal average power density. The exposure raised eyelid temperature by 1.0-1.2 degrees C. Experiment I consisted of nine 4-hour exposures over three weeks.
Liu YX et al. · 2012
Researchers exposed rat astrocytes and C6 glioma cells to 1950-MHz TD-SCDMA electromagnetic fields for 12, 24, and 48 hours to investigate whether the radiation would alter glial cell biology and act as a tumor-promoting agent. After 48 hours of exposure, mitochondria were damaged and significant apoptosis of astrocytes was induced, with increased expression of bax and a reduced level of bcl-2. Astrocytes did not form tumors in either the control or exposed groups, and exposed C6 glioma cells showed no significant differences in biological features or tumor formation ability compared with unexposed cells.
Park J, Kwon JH, Kim N, Song K · 2017
Researchers exposed HT22 mouse hippocampal neuronal cells and SH-SY5Y human neuroblastoma cells to 1950 MHz RF-EMF at a SAR of 6 W/kg for 2 hours per day over 3 days. They analyzed mRNA and protein expression of key genes involved in Aβ processing. In HT22 cells, mRNA levels of APP, BACE1, ADAM10 and PSEN1 decreased, while APP mRNA was unchanged in SH-SY5Y cells. Protein expression of APP and BACE1 and secreted Aβ peptide did not differ significantly between exposed and control cells.
Bouji M, Lecomte A, Gamez C, Blazy K, Villégier AS. · 2016
Researchers exposed aged (22–24 months) and young (4–6 months) adult male rats to head RF-EMF exposures at 900 MHz, with a specific absorption rate of 6 W/kg, for 45 minutes per day for 1 month. Aged rats showed deficits in spatial learning, exploration, anxiety-related behaviors, and increased hippocampal ILs and cortical IL-1β. The senescence-typical neurobiological deficits were not modified by RF-EMF exposures, and the study did not support the hypothesis of a specific cerebral vulnerability to RF-EMF during senescence. RF-EMF-exposed rats, with young and aged adults pooled, had decreased anxiety-related behaviors in the elevated plus maze.
Yang XS, He GL, Hao YT, Xiao Y, Chen CH, Zhang GB, Yu ZP. · 2012
Researchers exposed rats to 2.45 GHz electromagnetic fields (the same frequency as WiFi and microwave ovens) and found that their brain cells produced stress proteins in response. The hippocampus, a brain region crucial for memory and learning, showed increased levels of heat shock proteins (HSP27 and HSP70), which cells produce when they're under stress. This provides direct biological evidence that EMF exposure triggers a stress response in brain tissue.
Bouji M, Lecomte A, Hode Y, de Seze R, Villégier AS · 2012
Researchers assessed the effects of a single GSM exposure at 900 MHz with a specific absorption rate of 6 W/kg on young adult (6-week-old) and middle-aged (12-month-old) rats. The study measured brain IL-1β and IL-6, plasmatic corticosterone levels, and emotional memory. Results showed an IL-1β increase in the olfactory bulb and enhanced contextual emotional memory in GSM-exposed middle-aged rats, while plasmatic corticosterone levels increased in GSM-exposed young adults. Acute GSM exposure did not induce astrocyte activation, in contrast to previously published work.
Bouji M, Lecomte A, Hode Y, de Seze R, Villégier AS. · 2012
French researchers exposed young and middle-aged rats to cell phone radiation (900 MHz) for 15 minutes to study brain effects. They found that older rats showed increased brain inflammation and enhanced emotional memory, while younger rats had elevated stress hormones. The study reveals that age significantly affects how the brain responds to radiofrequency radiation.
Yang XS, He GL, Hao YT, Xiao Y, Chen CH, Zhang GB, Yu ZP. · 2012
Researchers exposed adult male Sprague-Dawley rats to a 2.45 GHz electromagnetic field at a specific absorption rate of 6 W/kg, or to sham conditions, then examined gene and protein expression in the hippocampus. Of 2048 candidate genes examined, 23 were upregulated and 18 were downregulated. Two heat shock proteins, HSP27 and HSP70, stood out because their expression levels were increased in the rat hippocampus. The researchers concluded that their data provide direct evidence that exposure to electromagnetic fields elicits a stress response in the rat hippocampus.
Yang X, He G, Hao Y, Chen C, Li M, Wang Y, Zhang G, Yu Z · 2010
Researchers studied how electromagnetic field exposure affects N9 microglial cells and the role of the JAK2-STAT3 signaling pathway in any resulting pro-inflammatory responses. EMF significantly induced phosphorylation of JAK2 and STAT3, and also dramatically increased the expression of CD11b, TNF-α, and iNOS, and the production of NO. When cells were pretreated with the JAK inhibitor P6, phosphorylation of JAK2 and STAT3 was strongly suppressed, and expression of CD11b, TNF-α, and iNOS was suppressed at 12 hours but not at 3 hours after EMF exposure.
