Unknown authors · 2008
Researchers used a rat model of chemically induced B acute lymphoblastic leukemia to test effects of 50 Hz magnetic fields with and without harmonics. The experiment included 280 rats and compared body weight, survival time, bone marrow blast cells, cumulative leukemia incidence, and leukemia type between exposed and unexposed groups. No significant differences were found for any parameter (p > 0.05). Results did not support the hypothesis that ELF-MFs, with or without harmonics, affect the development of B acute lymphoblastic leukemia in children.
Unknown authors · 2008
Researchers exposed groups of 108 DMBA-treated Fischer 344 rats to a 100 muT, 50 Hz magnetic field or sham exposure for 26 weeks. MF exposure significantly facilitated mammary tumorigenesis. The incidence of histologically verified adenocarcinomas was increased by 45% (P = 0.0095). The most pronounced effect on tumor incidence was seen in the cranial inguinal complexes.
Unknown authors · 2008
Researchers exposed 280 rats to 50 Hz magnetic fields (100 microT) while chemically inducing leukemia to test whether power line frequencies promote cancer development. The study found no differences in survival, leukemia incidence, or disease progression between exposed and unexposed animals. This suggests that power line frequency magnetic fields do not accelerate leukemia development in this animal model.
Unknown authors · 2008
Researchers exposed Fischer 344 rats to power line frequency magnetic fields (100 µT at 50 Hz) for 26 weeks after treating them with a cancer-causing chemical. The magnetic field exposure increased breast cancer rates by 45% compared to unexposed rats. This study suggests that common household and power grid magnetic fields may promote breast cancer development.
Pavicic I, Trosic I · 2008
Researchers exposed V79 cells to continuous wave frequencies of 864 MHz and 935 MHz for 1, 2, or 3 hours. Growth was significantly increased after two- and three-hour exposures to 864 MHz and after three-hour exposure to 935 MHz, measured 72 hours after irradiation. Colony-forming ability and cell viability did not significantly differ from control cells. The two fields showed similar effects on growth, colony-forming ability, and viability, with impact being time-dependent.
Inoue S, Motoda H, Koike Y, Kawamura K, Hiragami F, Kano Y. · 2008
Exposure to 2.45 GHz microwave irradiation at 200 W increased neurite outgrowth frequency about 10-fold compared to non-irradiated controls. The increase was prevented by adding a p38 MAPK inhibitor. Microwave treatment did not cause toxicity, unlike heat shock at 45°C.
Türközer Z, Güler G, Seyhan N. · 2008
Researchers aimed to evaluate the effects of varied 50 Hz electric field exposure on lipid peroxidation and antioxidant enzyme activities in guinea pig brain homogenates. Guinea pigs were exposed to electric fields ranging from 2 to 5 kV/m for three days, eight hours per day, in both vertical and horizontal directions. No statistically significant differences were found between exposed and sham groups in lipid peroxidation levels or enzyme activities at any field strength or direction. Comparisons between vertical and horizontal exposure directions also showed no significant differences.
Türközer Z, Güler G, Seyhan N · 2008
Researchers exposed guinea pigs to powerful electric fields (the kind found near high-voltage power lines) for 8 hours daily over three days to see if it would damage brain tissue through oxidative stress. They found no statistically significant effects on brain cell damage markers or antioxidant defenses, even at the highest exposure levels tested. While this suggests these particular electric field exposures may not cause measurable brain oxidative damage in the short term, the researchers noted some non-significant trends that warrant further investigation.
Prisco MG et al. · 2008
Johansson A et al. · 2008
Fifteen subjects with atopic dermatitis and 15 matched controls were exposed for 30 min to a 900 MHz GSM mobile phone-like RF field at 1 W/kg. Blood samples were taken before and after exposure to measure serum levels of substance P (SP), TNF R1, and brain derived neurotrophic factor (BDNF). At baseline, the atopic dermatitis group had significantly higher serum TNF R1 and significantly lower BDNF than controls, while SP did not differ. No effects of RF exposure were found on any of the measured substances. Symptom reports were too few to evaluate a possible correlation with exposure.
Moisescu MG, Leveque P, Bertrand JR, Kovacs E, Mir LM · 2008
Researchers designed a device for continuous microscopic observation of cells exposed to modulated EMF similar to mobile phone signals. The system allowed follow-up of cell progression into mitosis under controlled temperature and CO2 environment. Cells exposed to 900 MHz modulated EMF for 1 hour at 30 degrees C and 2.2 W/kg showed increased endocytosis rate but no alteration in mitosis progression or duration. The exposure system was validated by cell endocytosis measurements.
Ross ML, Koren SA, Persinger MA. · 2008
Researchers tested whether a weak magnetic field pulsed over the left prefrontal brain region at the moment of accepting or refuting a statement could increase the likelihood of later accepting a false statement as true. Fifty men and women were each exposed to one of four magnetic field conditions, or a sham field, over the left prefrontal region above the eyebrow. Groups that received the burst-firing or 25 Hz pulsed fields during the refutation process accepted about twice the number of false statements as true compared to those in the 50 Hz or sham-field conditions. The treatments did not significantly affect the numbers of true statements accepted as false.
Unknown authors · 2008
Researchers exposed human lens epithelial cells intermittently for 24 hours to radiofrequency fields at specific absorption rates of 1, 2, 3, and 4 W/kg. DNA damage measured by alkaline comet assay increased significantly at 3 and 4 W/kg, while double-strand breaks increased only at 4 W/kg. Intracellular reactive oxygen species levels rose significantly at 3 and 4 W/kg, and cells exposed to 4 W/kg showed G0/G1 cell cycle arrest. Apoptosis did not differ between exposed and sham groups, and all observed effects were blocked when the radiofrequency field was superposed with 2 muT electromagnetic noise.
Unknown authors · 2008
This 2008 study exposed human eye lens cells to 1.8 GHz cell phone radiation at various power levels for 24 hours. Researchers found DNA damage and cellular stress at higher exposure levels, but discovered that adding electromagnetic 'noise' completely blocked these harmful effects. However, this study was later retracted by the journal.
Zhang SZ, Yao GD, Lu DQ, Chiang H, Xu ZP. · 2008
Researchers exposed primary cultured rat neurons to 1.8 GHz RF EMF at a SAR of 2 W/kg and used a gene array to look for changes in gene expression. Among 1200 candidate genes screened, 24 were up-regulated and 10 were down-regulated, associated with functions including cytoskeleton, signal transduction, and metabolism. The effect of 24-hour exposure on gene expression was more obvious than that of 6-hour exposure, and intermittent exposure had a more obvious effect than continuous exposure.
Zhang SZ, Yao GD, Lu DQ, Chiang H, Xu ZP. · 2008
Researchers exposed rat brain cells to cell phone radiation (1.8 GHz) for up to 24 hours. The radiation altered 34 genes controlling brain cell structure, communication, and metabolism. Changes were stronger with intermittent exposure patterns, suggesting cell phone signals may affect brain function.
Partsvania B, Sulaberidze T, Modebadze Z, Shoshiashvili L. · 2008
Researchers studied how extremely low-frequency magnetic fields at 8.34 and 217 Hz affected the ability of single neurons in the mollusk Helix Pomatia to habituate to repeated stimuli. Brain ganglia were exposed to magnetic fields with peak values between 1 and 6 mT using Helmholtz coils, and neuron activity was recorded with a standard microelectrode technique. Exposure caused dehabituation, which the researchers described as occurring through degradation of the signal to noise ratio and alteration of the neuron's normal function.
Nittby H et al. · 2008
Swedish researchers exposed rats to cell phone radiation at 1,800 MHz for six hours and found significant changes in brain gene expression. The radiation altered genes controlling cell membranes and signal transmission in memory-critical brain regions, occurring at levels similar to extended human cell phone use.
Manti L et al. · 2008
Researchers exposed human peripheral blood lymphocytes in vitro to a UMTS signal at a frequency carrier of 1.95 GHz for 24 hours at 0.5 and 2.0 W/kg SAR. Cells were also given 4 Gy of X rays immediately before RF radiation or sham exposures, and chromosome aberrations were measured by fluorescence in situ hybridization. No significant variations due to the UMTS exposure were found in the fraction of aberrant cells, but the frequency of exchanges per cell showed a small but statistically significant increase of 0.11 exchange per cell compared to 0 W/kg SAR.
Yao K, Wu W, Wang K, Ni S, Ye P, Yu Y, Ye J, Sun L. · 2008
Researchers exposed cultured human lens epithelial cells (HLECs) to a 1.8 GHz GSM radiofrequency field for 2 hours at specific absorption rates of 1, 2, 3, and 4 W/kg, then measured intracellular reactive oxygen species (ROS) and DNA damage. After exposure to 1.8 GHz RF for 2 h, HLECs exhibited significant intracellular ROS increase in the 2, 3, and 4 W/kg groups, and RF at 3 W/kg and 4 W/kg induced significant DNA damage consisting mainly of single strand breaks. When the radiofrequency field was superposed with 2 μT electromagnetic noise, the noise blocked the RF-induced ROS increase and DNA damage.
Ammari M et al. · 2008
Researchers measured GFAP expression in rat brain areas using immunocytochemistry to evaluate glial changes 10 days after chronic exposure to a GSM 900 MHz signal. Rats were exposed 5 days a week for 24 weeks at a brain-averaged SAR of 1.5 W/kg for 45 minutes per day, or at 6 W/kg for 15 minutes per day. Compared with sham or cage control animals, rats exposed at 6 W/kg had increased GFAP stained surface areas (p < 0.05), while exposure at 1.5 W/kg did not increase GFAP expression. The researchers noted that chronic exposure at 6 W/kg may induce persistent astroglia activation in the rat brain, which they described as a sign of a potential gliosis.
Ammari M, Lecomte A, Sakly M, Abdelmelek H, de-Seze R · 2008
Researchers measured cytochrome oxidase levels in rat brains using histochemical methods to evaluate regional brain metabolic activity after GSM 900 MHz signal exposure. Rats were exposed either for 45 minutes per day at a SAR of 1.5 W/Kg or for 15 minutes per day at a SAR of 6 W/Kg, over seven days. At 6 W/Kg, decreased CO activity was found in areas of the prefrontal and frontal cortex, the hippocampus, and the posterior cortex, while exposure at 1.5 W/Kg did not affect brain activity.
Joubert, V., Bourthoumieu, S., Leveque, P. and Yardin, C. · 2008
Researchers exposed rat primary neuronal cultures to a continuous-wave 900 MHz radiofrequency field at a specific absorption rate of 2 W/kg for 24 hours. A statistically significant difference in the rate of apoptosis was found in the RF-field-exposed neurons compared to the sham-, 37°C- and 39°C-exposed neurons either 0 or 24 h after exposure using both methods. The percentage of AIF-positive nuclei in RF-field-exposed neurons was increased by three- to sevenfold compared to other conditions, while no increase in caspase 3 activity was found.
Odaci E, Bas O, Kaplan S · 2008
Researchers investigated the effects of prenatal EMF exposure on the number of granule cells in the dentate gyrus of 4-week-old rats. Pregnant rats in the exposed group were subjected to a 900 MHz EMF for 60 min/day between the first and last days of gestation. The results showed that prenatal EMF exposure caused a decrease in the number of granule cells in the dentate gyrus (P < 0.01).
Ahmed Z, Wieraszko A. · 2008
Researchers investigated the influence of a pulsed magnetic field on hippocampal evoked potentials in vitro. Exposure to a pulsed magnetic field at 0.16 Hz and 15 mT, applied for 30 minutes, amplified the population spike and the slope of EPSP recorded from hippocampal tissue. The amplification was additive to previously induced long-term potentiation and occurred in an NMDA-independent way. The pulsed magnetic field also modified paired-pulse facilitation and paired-pulse inhibition, suggesting it affects both excitatory and inhibitory processes in the hippocampus.
