Manikonda PK et al. · 2007
Researchers exposed rats to 50 Hz magnetic fields at 50 and 100 μT intensities for 90 days and then examined hippocampal tissue. Compared to controls, ELF exposure was associated with increased intracellular calcium levels and changes in the activity of several calcium-related enzymes. Binding to NMDA receptors was also found to be decreased in exposed rats. The researchers suggested that perturbed neuronal functions caused by ELF exposure may involve altered calcium signaling contributing to aberrant NMDA receptor activities.
Cheun BS, Yi SH, Baik KY, Lim JK, Yoo JS, Shin HW, Soh KS · 2007
Researchers studied biophoton emission from Madin-Darby canine kidney (MDCK) cells treated with hydrogen peroxide, with and without exposure to a 60 Hz AC magnetic field. Hydrogen peroxide increased biophoton emission from the cells, and the increase was dependent on the amount of hydrogen peroxide applied. When the 60 Hz AC magnetic field was applied, the decay of chemiluminescence intensity took a different path compared to cells not exposed to the field.
Che Y, Sun H, Cui Y, Zhou D, Ma Y. · 2007
Researchers exposed young chicks to magnetic fields from power lines for 20 hours daily and tested their learning ability. Chicks with prolonged exposure showed significantly impaired learning and memory compared to unexposed chicks, suggesting extended magnetic field exposure may interfere with brain development.
Manikonda PK et al. · 2007
Researchers exposed young rats to magnetic fields from power lines for 90 days, then examined their brain tissue. The exposure disrupted calcium signaling and reduced NMDA receptor function in the hippocampus, suggesting power line magnetic fields could interfere with learning and memory development.
Zhao TY, Zou SP, Knapp PE. · 2007
Researchers exposed primary cultured neurons and astrocytes to GSM cell phone emissions at 1900 MHz for 2 hours. Neurons showed up-regulation of caspase-2, caspase-6, and Asc genes in both 'on' and 'stand-by' modes. Astrocytes showed up-regulation of the same genes only in 'on' mode and also up-regulated the Bax gene.
Hung CS, Anderson C, Horne JA, McEvoy P. · 2007
Researchers exposed 10 healthy young adults to a GSM mobile phone in 'talk mode' for 30 minutes during the day, then measured how long it took them to fall asleep afterward. They found that exposure to the phone's talk-mode signal significantly delayed the onset of sleep compared to when the phone was off or in other modes. The study suggests that the specific radio frequency patterns used during phone calls may interfere with the brain's natural transition to sleep.
Unknown authors · 2007
Researchers analyzed 60 children with acute leukemia and 59 matched controls in a city in North-Western Iran. They assessed exposure to very high voltage power lines of 123, 230, and 400 kilovolts. Fourteen cases (23.5%) lived within 500 meters of such lines compared with two controls (3.3%), giving an odds ratio of 8.67. Fifteen cases (25%) experienced magnetic fields above 0.45 microtesla versus five controls (8.5%), with an odds ratio of 3.60.
Hamann W, Abou-Sherif S, Thompson S, Hall S. · 2006
Researchers applied pulsed radiofrequency (20 ms of 500-kHz RF pulses at 2 Hz, max 42°C) to the sciatic nerve or L4 anterior primary ramus in adult rats. Controls included sham-operated and L4 axotomised rats, and tissues were examined 14 days later. Axotomy upregulated ATF3 in L4 DRG neurons regardless of size. PRF applied near the DRG significantly and selectively increased ATF3 in small and medium neurons, while PRF applied to the sciatic nerve in mid-thigh caused no obvious changes.
Unknown authors · 2006
Researchers conducted a population-based case-control study covering areas with 54% of Japanese children, analyzing 312 cases of acute lymphoblastic or myelocytic leukemia and 603 matched controls. Weekly mean magnetic field levels were measured in the child's bedroom, with measurements for each case-control set taken close in time to control for seasonal variation. The odds ratio for all leukemia combined was 2.6 (95% CI 0.76–8.6) and for acute lymphoblastic leukemia alone was 4.7 (95% CI 1.15–19.0) for bedroom fields of 0.4 μT or higher versus below 0.1 μT.
Frahm J, Lantow M, Lupke M, Weiss DG, Simkó M · 2006
Researchers investigated whether extremely low frequency electromagnetic fields affect cellular functions and immunologic parameters of mouse macrophages. Magnetic field exposure led to a 1.6-fold increased uptake of latex beads in exposed cells compared to controls after 45 minutes. IL-1β formation increased significantly after 4 hours and reached a maximum 12.3-fold increase after 24 hours compared to controls. All tested flux densities significantly stimulated free radical formation, and no significant differences in micronucleus formation were found in exposed cells.
Christ A, Samaras T, Klingenböck A, Kuster N. · 2006
The study investigated electromagnetic near-field absorption in layered biological tissue from 30 MHz to 6000 MHz. Two effects can increase SAR in layered tissue versus homogeneous liquid: standing wave effects at larger distances depending on frequency and fat thickness, and high local skin absorption from reactive E-fields in the very close near-field. A conservative exposure estimate can be obtained by applying a multiplication factor of 1 to 3 to current dosimetric values.
Simkó M et al. · 2006
The study investigated Hsp70 expression and free radical release in human Mono Mac 6 cells exposed to ultrafine particles and radiofrequency electromagnetic fields. Ultrafine particle exposure increased free radical release by 40-45% above negative control, an effect stronger than heat treatment. Radiofrequency electromagnetic field exposure alone did not change free radical levels. Combined exposure to RF and ultrafine particles did not enhance the particle effect on free radicals. Heat treatment increased Hsp70 expression in a time-dependent manner, while ultrafine particles, RF fields, or their combination had no effect on Hsp70.
Keshvari J, Keshvari R, Lang S. · 2006
Sakuma N et al. · 2006
Researchers conducted a large-scale in vitro study to test whether modulated RF fields from mobile radio base stations act as a DNA damaging agent. Human glioblastoma A172 cells and normal human IMR-90 fibroblasts were exposed to 2.1425 GHz CW and W-CDMA radiation. A172 cells were exposed to W-CDMA at SARs of 80, 250, and 800 mW/kg and CW at 80 mW/kg for 2 and 24 hours, while IMR-90 cells were exposed to both modulations at 80 mW/kg for the same periods. No significant differences in DNA strand breaks were observed between exposed groups and sham controls using alkaline comet assays. The authors concluded that low-level exposures do not act as a genotoxicant up to a SAR of 800 mW/kg.
Tuschl H, Novak W, Molla-Djafari H. · 2006
The study assessed whether GSM-modulated RF fields have adverse effects on the functional competence of human immune cells. Exposure was performed at GSM Basic 1950 MHz with an SAR of 1 mW/g in an intermittent mode of 5 minutes on and 10 minutes off for 8 hours. Researchers evaluated intracellular cytokine production, immune-relevant gene activity, and cytotoxicity of lymphokine-activated killer cells using blood from at least 15 donors per parameter. No statistically significant effects of exposure were found.
Hirose H et al. · 2006
Researchers conducted a large-scale in vitro study to test whether modulated RF fields from mobile radio base stations induce apoptosis or stress responses activating p53. Human glioblastoma A172 cells were exposed to W-CDMA radiation at SARs of 80, 250, and 800 mW/kg and CW radiation at 80 mW/kg for 24 or 48 hours, while human IMR-90 fibroblasts were exposed to both modulations at 80 mW/kg for 28 hours. No significant differences in apoptosis, phosphorylated p53 at serine 15, total p53, or downstream gene expression were found between exposed and sham-exposed cells.
Wang J et al. · 2006
Researchers exposed A172 cells to 2450 MHz high-frequency electromagnetic fields at SARs of 5-200 W/kg and included heat controls at 38-44°C. HSP70 expression increased in a time- and dose-dependent manner at SARs above 50 W/kg for 1-3 hours, similar to heat controls. HSP27 expression did not change significantly with HFEMF exposure or heating, but HSP27 phosphorylation increased transiently at 100 and 200 W/kg, exceeding the effect of heating at 40-44°C, peaking after 1 hour at 100 W/kg.
Unknown authors · 2006
Researchers studied the effect of 50 Hz electromagnetic field on the thyroid gland using light and transmission electron microscopes. Two-month-old male rats were exposed to an EMF of 100-300 μT and 54-160 V m-1 for 4 h a day, 5 days a week for 1 month. The EMF group showed a predominance of microfollicles with less colloid content and dilated blood capillaries. Stereological counting revealed a statistically significant increase in the volume density of follicular epithelium, interfollicular tissue, blood capillaries, and the thyroid activation index, while the volume density of colloid significantly decreased.
Takashima Y et al. · 2006
Researchers exposed cells to radio frequency electromagnetic fields at 2.45 GHz to examine cell growth, survival, and cell cycle distribution across a wide range of specific absorption rates. When cells were exposed to a continuous RF field at SARs from 0.05 to 100 W/kg for 2 h, cellular growth rate, survival, and cell cycle distribution were not affected. At 200 W/kg, the cell growth rate was suppressed and cell survival decreased, and the temperature of the medium rose to 44.1 degrees C. The researchers suggested that the proliferation disorder is caused by the thermal effect.
Unknown authors · 2006
The study used a crossover design with healthy premenopausal women exposed to a 60-Hz magnetic field of 5 to 10 mG greater than ambient levels for 5 consecutive nights during the early to midluteal phase of the menstrual cycle. Magnetic field exposure was associated with decreased 6-sulfatoxymelatonin levels, but no changes in reproductive hormone levels were observed. Participants using prescription medications and anovulatory participants had more pronounced decreases in 6-sulfatoxymelatonin levels with magnetic field exposure.
Paulraj R, Behari J · 2006
The control group was sham irradiated. The study revealed a statistically significant decrease in PKC activity in the hippocampus compared to the rest of the brain and controls. Electron microscopy showed an increase in glial cell population in the exposed group.
Chauhan V et al. · 2006
Researchers exposed human lymphoblastoma TK6 cells to 1.9 GHz pulse-modulated RF fields at SARs of 1 and 10 W/kg. They assessed expression of proto-oncogenes FOS, JUN, and MYC using real-time RT-PCR. They also monitored transcript levels of the heat-shock proteins HSP27 and inducible HSP70. Transcript levels in RF-exposed cells showed no significant difference compared to sham-exposed cells. Positive heat-shock controls showed significant elevation of HSP27, HSP70, FOS, and JUN, and a decline in MYC mRNA.
Unknown authors · 2006
Researchers exposed female mice to 50 Hz, 1.2 mT electromagnetic fields for 8 hours per day throughout pregnancy. Exposed dams gained weight more slowly (29.0% vs 47.8%) and had a lower producing rate (60% of controls), with miscarriages, fetal loss, and malformed fetuses observed. The average number of offspring per mouse decreased (11 ± 1.6 vs 7 ± 2.0), and prenatally exposed offspring showed slower weight gain in the first two weeks and delayed eye opening and tooth eruption.
Chauhan V et al. · 2006
Researchers exposed HL-60 and MM6 cells to intermittent 1.9 GHz pulse-modulated RF fields at SARs of 1 and 10 W/kg for 6 hours. No significant changes in gene expression were found between sham-exposed and RF-exposed groups in either cell line. Positive heat-shock controls showed significant increases in HSP27, HSP70, c-fos, and c-jun at both time points.
Hondou T et al et al. · 2006
Researchers conducted a numerical investigation using a realistic human body model and an actual elevator size to assess SAR from a mobile phone modeled as a dipole antenna at 16 mm from the head. They used finite-difference time-domain technique with a supercomputer at frequencies of 900, 1500, and 2000 MHz with 250 mW transmitting power. Results showed that peak 10-g SAR depends on passenger and antenna position, with substantial increases in whole-body average SAR and peak 10-g SAR in the elevator over free-space values. However, the maximum values met international RF safety guidelines, with whole-body average SAR at 4.4% and peak spatial-average SAR at 78% of the guideline.
