Browse 6,486 peer-reviewed studies on electromagnetic field health effects from 4 research libraries.
Showing 1,318 studies matching "radiofrequency"
Dasdag S, Yavuz I1, Bakkal M, Kargul B. · 2014
A control group of 7 rats underwent the same procedure with the generator turned off. Enamel microhardness was measured at the end of the study and showed no significant difference between groups (p>0.05).
Khalil AM, Abu Khadra KM, Aljaberi AM, Gagaa MH, Issa HS. · 2014
The study aimed to examine oxidant and antioxidant status in saliva of cell phone users by collecting samples before and after 15- and 30-minute calls. Saliva was analyzed for malondialdehyde, 8-oxo-dG, and antioxidant capacities using ORAC and HORAC assays. Mean 8-oxo-dG and protein concentrations peaked at 15 minutes, while HORAC, ORAC, and MDA levels increased progressively and reached maximum at 30 minutes. Talking time had no significant effect on 8-oxo-dG, MDA, ORAC, or HORAC levels. The authors concluded that there is no relationship between radiofrequency radiation exposure and changes in the salivary oxidant/antioxidant profile.
Klose M et al. · 2014
Female Wistar rats from 14 days to 19 months were exposed in the head region for 2 hours per day, 5 days per week to a GSM-modulated 900 MHz field at SAR values of 0, 0.7, 2.5, and 10 W/kg. Four behavioral and learning tests (rotarod, Morris water maze, 8-arm radial maze, open field) were performed three times in juvenile, adult, and presenile rats. No profound differences were identified between exposure groups, though rotarod data showed significantly longer holding times for sham-exposed rats on some days, but these findings were not consistent. The results do not indicate harmful effects of long-term RF-EMF exposure begun at an early age on development, learning, and behavior, even at relatively high SAR values.
Kang KA et al. · 2014
Researchers exposed U87, PC12, and SH-SY5Y neuronal cells to combined radiofrequency radiation at 837 MHz CDMA and 1950 MHz WCDMA with a specific absorption rate of 2 W/kg each for 2 hours. They also tested co-exposure with hydrogen peroxide or menadione and measured intracellular reactive oxygen species using flow cytometry with a fluorescent probe. Combined RF radiation alone did not consistently affect ROS levels in a time-dependent manner, and co-exposure with hydrogen peroxide or menadione showed no statistically significant change compared to the chemicals alone.
Zhou H et al. · 2014
Researchers used the finite-difference time-domain method to compute the specific absorption rate (SAR) of radio frequency (RF) waves in the human brain and to investigate the effects of geometry and polarisation on SAR value. The results suggested that high SAR values were found in the brain at approximately 250 MHz for vertical polarisation and 900-1200 MHz for both vertical and horizontal polarisation, which may be the result of head resonance at these frequencies.
Vijayalaxmi, Prihoda TJ. · 2014
The study aimed to investigate whether mobile phone radiofrequency fields and brain cancer show an adaptive response. The authors re-examined all odds ratios from the INTERPHONE study published in 2011. Their analysis showed 24.3% decreased and 0.7% increased risk for meningioma and 22.1% decreased and 6.6% increased risk for glioma. They hypothesized that the overwhelming evidence for decreased risk may be due to induction of an adaptive response.
Varsier N et al. · 2014
Researchers analyzed the influence of pregnancy stage and fetus position on whole-body and brain exposure of the fetus to radiofrequency electromagnetic fields at 2100 MHz. They used semi-homogeneous pregnant woman models between 8 and 32 weeks of amenorrhea. Whole-body and average brain exposures decreased during the first trimester. From the beginning of the second trimester, whole-body and average brain exposures were quite stable. A fetal head-up position produced slightly higher brain exposure than a head-down position, while whole-body exposures were similar.
Thors B et al. · 2014
The paper investigated different methods for practical numerical radio frequency exposure compliance assessments of radio base station products. Assessments based on peak field strengths were less computationally intensive but led to larger compliance distances than spatial averaging of electromagnetic fields combined with localized SAR assessments. For adult exposure, shorter compliance distances were obtained using assessments based on localized and whole-body SAR. Numerical simulations using base station products with MIMO transmission schemes agreed with reference measurements.
Sepehrimanesh M et al. · 2014
Twenty adult male Sprague-Dawley rats were exposed to 900 MHz RF-EMF for 1, 2, or 4 hours per day over 30 days, with a sham-exposed control group. At the end of the experiment, the long-time exposure group showed significantly higher FSH and LH levels than the sham group. The long-time exposure group also had significantly increased activin B and prolactin, decreased inhibin B compared to sham and short-time exposure groups, and decreased testosterone compared to short- and moderate-time exposure groups.
Mortazavi SM et al. · 2014
Researchers previously found that radiofrequency radiation exposure can induce a survival adaptive response in laboratory animals. They also reported that pre-exposing mice to GSM mobile phone radiation increased resistance to subsequent Escherichia coli infection. In this study, animals receiving both radiofrequency pre-exposure and bacterial challenge had a 56% survival rate versus 20% for those receiving only the bacterial challenge.
Jovanovic D, Bragard G, Picard D, Chauvin S. · 2014
Researchers used three 3G HSPA smartphones from different manufacturers to make 220 two-minute calls on a national mobile network in Paris between 28 July and 04 August 2011. The SYRPOM measuring equipment recorded radiation power levels and frequency bands at a sampling rate of 20,000 per second. The mean normalized power was 0.75% of maximum for 3G VoIP calls and 0.22% for 3G VoCS calls. The very low average power levels indicate that RF exposure from 3G devices with VoIP or VoCS is far from exceeding the basic restrictions of current SAR exposure limits.
Ghanmi A, Varsier N, Hadjem A, Conil E, Picon O, Wiart J. · 2014
Researchers analyzed how phone position affects brain exposure by comparing SAR from two GSM phone models. They tested 80 phone positions selected via Latin hypercube sampling. They estimated SAR10g in the head, SAR1g in the brain, and SAR in brain structures at 900 and 1800 MHz. Results show SAR distributions in the brain are sensitive to phone position. For 5–10% of positions, SAR10g in head and SAR1g in brain were 20% higher than the standard cheek position, and the SAM model was conservative for 95% of positions.
Geronikolou S et al. · 2014
Egg laying in the second generation was compared between exposed and non-exposed cultures using advanced statistics. The 900 MHz exposure showed statistical significance, while the cordless phone exposure showed limited statistical significance. The researchers also calculated and simulated the near-field radiation patterns inside the vials. They found that the power difference between the two fields becomes null when the cylinder radius and antenna height increase.
Cabot E et al. · 2014
Researchers used numerical modeling to analyze electromagnetic radiation exposure of pregnant women and their fetuses at three gestational stages in near-field and far-field conditions. When the mother was exposed at general public reference levels, the fetus was sufficiently shielded and maternal exposure remained below or on the order of the basic restriction.
Aydogan F et al. · 2014
Thirty Wistar albino rats were divided into four groups. Groups A and B served as control groups for 10 days and 40 days with six rats each, while groups C and D were exposure groups with nine rats each. The rats were exposed to 2100 MHz radiofrequency radiation simulating a third generation mobile phone for 6 hours per day, 5 days per week, for 10 or 40 days. Exposure groups showed numerous histopathological changes in the parotid gland, with more prominent changes after 40 days compared to 10 days.
Aguirre E et al. · 2014
The aim of the study is to observe Analysis of estimation of electromagnetic dosimetric values from non-ionizing radiofrequency fields in conventional road vehicle environments. A dosimetric evaluation inside a conventional car is performed with an in-house 3D Ray Launching computational code and compared with measurement results of wireless sensor networks located inside the vehicle. The results can aid in an adequate assessment of human exposure to non-ionizing radiofrequency fields, taking into account the impact of the morphology and the topology of the vehicle for current as well as for future exposure limits.
Adibzadeh F et al. · 2014
Researchers performed detailed dosimetric simulations for 20 head models to quantify how head morphology affects RF dose in different brain regions. The variation in averaged SAR among heads reached up to 16.4 dB in a 1 cm³ brain cube using the field-sensor method and up to 15.8 dB in the medulla using the Talairach method. Head models were exposed to generic mobile phone fields at 835 and 1900 MHz in tilted and cheek positions. The authors concluded that head morphology is an important uncertainty source and that dosimetric analyses for specific brain regions should use real morphology.
Seckin E et al. · 2014
Pregnant rats and their offspring were exposed to 900 MHz and 1800 MHz Global System for Mobile Communications radiofrequency radiation for one hour per day during pregnancy and for 21 days after birth. Distortion product otoacoustic emission tests showed no significant difference among the groups. Electron microscopy revealed significant differences in the numbers of normal, apoptotic, and necrotic cells among the groups. The findings indicated cellular structural damage in the cochlea caused by radiofrequency radiation exposure during cochlear development.
Saikhedkar N et al. · 2014
Researchers exposed 30-day-old rats to 900 MHz radio waves from a mobile handset for 4 hours per day over 15 days. Exposed rats showed more anxiety and poor learning compared to control and sham groups. Antioxidant enzymes and non-enzymatic antioxidants changed significantly and lipid peroxidation increased in exposed rats.
Valbonesi P, Franzellitti S, Bersani F, Contin A, Fabbri E. · 2014
Researchers exposed rat PC12 cells to 1.8 GHz continuous wave or GSM-modulated signals at a SAR of 2 W/kg for 4, 16, or 24 hours. HSP70 gene expression was measured by RT-PCR, while HSP70 protein and MAPK phosphorylation were measured by Western blotting. Only the GSM-217Hz signal increased HSP70 transcription after 16 or 24 hours of exposure. HSP70 protein levels and three MAPK signaling pathways were unchanged by any of the signals.
Urbinello D, Joseph W, Verloock L, Martens L, Röösli M. · 2014
Measurements of RF-EMF exposure in 11 frequency bands from FM to WLAN were performed in three European cities over one year. Highest exposure levels occurred in public transports with arithmetic means of 0.84 V/m in Brussels, 0.72 V/m in Ghent, and 0.59 V/m in Basel. Outdoor exposure increased by 57.1% in Basel (p<0.001), 20.1% in Ghent (p=0.053), and 38.2% in Brussels (p=0.012) over one year. Exposure increases were most consistent in outdoor areas due to mobile phone base stations. Levels remained far below regulatory limits.
Urbinello D et al. · 2014
Researchers performed measurements in Amsterdam, Basel, Ghent, and Brussels using a portable measurement device. Arithmetic mean values for mobile phone base station exposure ranged from 0.22 V/m in Basel to 0.41 V/m in Amsterdam across all outdoor areas. The 95th percentile for total RF-EMF exposure varied between 0.46 V/m in Basel and 0.82 V/m in Amsterdam, and the 99th percentile between 0.81 V/m in Basel and 1.20 V/m in Brussels. All measured exposure levels were far below the international reference levels proposed by ICNIRP. The study did not find indications that lowering the regulatory limit results in higher mobile phone base station exposure levels.
Tas M et al. · 2014
The study used 14 adult Wistar Albino rats divided into sham and exposure groups of seven each. Exposed rats received 900 MHz RF radiation from a GSM signal generator for 3 hours per day, 7 days a week, for one year. No differences were found in sperm motility or concentration between groups. Exposed rats had higher rates of morphologically normal sperm but lower tunica albuginea thickness and Johnsen testicular biopsy scores.
Taberski K et al. · 2014
Researchers exposed 16 male Djungarian hamsters to 900 MHz GSM-modulated RF-EMF at SAR levels of 0, 0.08, 0.4, and 4 W/kg for one week per condition. Only at the highest SAR level did fur temperature increase by about 0.5°C, food consumption decrease, and daytime carbon dioxide production and respiratory quotient decrease.
Sannino A et al. · 2014
Researchers exposed human peripheral blood lymphocytes from four healthy donors to 1950 MHz radiofrequency fields at 0.3 W/kg for 20 hours, then challenged them with 1.0 or 1.5 Gy X-irradiation. After 72 hours of culture, they measured micronuclei incidence and found a significant decrease in micronuclei in cells exposed to both radiofrequency fields and X-rays compared to X-rays alone. The results suggested a radiofrequency-induced adaptive response and resistance to subsequent X-ray damage, though variability between donors was observed.