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.
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.
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.
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.
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.
Falone S et al. · 2008
Researchers continuously exposed female Sprague-Dawley rats to a sinusoidal 50 Hz, 0.1 mT magnetic field for 10 days. The study examined antioxidant protection systems and neurotrophic support in brain cortices, as a function of the age of the subjects. Exposure significantly affected antioxidant capability in both young and aged animals, but in opposite ways. The researchers suggested that exposure to these fields may act as a risk factor for oxidative stress-based nervous system pathologies associated with ageing.
Harakawa S et al. · 2008
Researchers examined how a 50 Hz sinusoidal electric field affected the voluntary behavior of Wistar rats using a conditioned place aversion response based on an aversive behavior against light environment. Rats conditioned without the electric field spent significantly less time in the white place, while rats conditioned with the electric field did not show such changes. The researchers considered that the aversion response to the light environment was interfered by exposure to the electric field.
Liu T, Wang S, He L, Ye K. · 2008
The study investigated whether anxiety levels could be affected by repeated extremely low frequency magnetic field (ELF MF) exposure of different daily durations. Rats exposed for 4 h/day showed increased anxiety-like behaviors in the open field test and the elevated plus maze test, without changes in locomotor activity, but showed no effect in the light/dark box test. Rats exposed for 1 h/day showed no effect in any of the tests.
Liu T, Wang S, He L, Ye K. · 2008
Researchers tested spatial learning and memory in rats using the Morris water maze after four weeks of daily exposure to a 50-Hz magnetic field of 2 mT for either one or four hours. Chronic exposure reduced the time rats took to find a hidden platform and improved long-term memory of the platform's former location. Short-term memory and motor activity were not affected.
Wang X et al. · 2008
Researchers exposed rats to extremely low-frequency electromagnetic fields (20 Hz, 14 mT) for one hour per day before daily morphine injections for 12 days, then measured dopamine D2 receptor density in the dorsal hippocampus during withdrawal. Morphine withdrawal alone significantly lowered D2 receptor density compared to saline controls, and ELF-EMF exposure during morphine treatment further reduced receptor density on the first and third withdrawal days. In both groups, D2 receptor density tended to recover as the number of withdrawal days increased.
Canseven AG, Coskun S, Seyhan N · 2008
Researchers exposed guinea pigs to 50 Hz magnetic fields at 1, 2, and 3 mT for 4 h/day and 8 h/day for 5 days, measuring malondialdehyde, nitric oxide, glutathione, and myeloperoxidase activity in heart and liver tissues. MDA levels increased in the liver in some groups but decreased in both liver and heart in group VII. The researchers concluded that field intensity and exposure duration are among the conditions that influence free radical formation and antioxidant enzyme behavior.
Erdal N, Gürgül S, Tamer L, Ayaz L · 2008
Researchers exposed adult Wistar-Albino rats to an extremely low frequency magnetic field (50 Hz, 1 mT, 4 hours per day) to study oxidative and nitrosative stress in liver tissue. 3-nitrotyrosine (3-NT) levels were significantly increased in exposed female rats compared to female controls, but no significant difference was found between exposed and control male rats. Malondialdehyde (MDA) levels showed no significant differences between control and exposed rats in either sex.
Falone S et al. · 2008
Italian researchers exposed young and older rats to 50 Hz magnetic fields from power lines for 10 days. Young rats strengthened their brain's antioxidant defenses, but older rats experienced significant weakening of these protective systems, suggesting aging brains are more vulnerable to EMF damage.
Hashish AH, El-Missiry MA, Abdelkader HI, Abou-Saleh RH · 2008
Ahmed Z, Wieraszko A. · 2008
Researchers exposed brain tissue from the hippocampus (memory center) to pulsed magnetic fields for 30 minutes. The neurons became significantly more electrically active, firing more signals and changing how they communicate. This shows magnetic fields can directly alter brain cell function.
Hashish AH, El-Missiry MA, Abdelkader HI, Abou-Saleh RH. · 2008
Researchers exposed mice to magnetic fields and 50 Hz electromagnetic fields (the type from power lines) for 30 days to study health effects. The exposed mice lost weight and showed signs of liver stress, including increased oxidative damage (cellular damage from unstable molecules) and changes in blood chemistry. The study suggests that prolonged exposure to these common electromagnetic fields may disrupt the body's ability to protect itself from cellular damage.
Unknown authors · 2008
Researchers exposed cultured human lens epithelial cells to 0.4 mT 50 Hz magnetic fields for 2, 6, 12, 24, and 48 hours. After exposure, cells were fixed with 4% paraformaldehyde and stained for gamma H2AX immunofluorescence, and foci were counted in at least 200 cells per sample. Cells with more than three foci per cell were classified as positive, and mean foci per cell and percentage of positive cells were used as indexes of DNA double-strand breaks. Exposure for 24 hours significantly increased mean foci per cell to 2.93 and positive cells to 27.88% compared with sham (1.77 and 19.38%, P<0.05), and exposure for 48 hours increased them to 3.14 and 31.00% (P<0.01), while 2, 6, and 12 hour exposures showed no significant difference (P>0.05).
Vecchio F et al. · 2007
Italian researchers exposed 10 people to cell phone radiation for 45 minutes while measuring their brain waves with EEG technology. They found that the radiation altered how the left and right sides of the brain communicate with each other, specifically disrupting the synchronization of alpha brain waves that are important for information processing. This suggests that cell phone emissions don't just affect individual brain cells, but can interfere with the coordinated electrical activity between different brain regions.
Krause CM, Pesonen M, Haarala Bjornberg C, Hamalainen H. · 2007
Researchers recruited two groups of 36 male participants each, one performing an auditory memory task and the other a visual working memory task under six exposure conditions. The study aimed to partially replicate earlier work and investigate effects of mobile phone EMF on event-related desynchronisation/synchronisation EEG responses during cognitive processing. EMF exposure produced modest effects on alpha band oscillatory responses but no effects on behavioural measures. The EEG effects were varying, unsystematic, and inconsistent with previous reports.
Unknown authors · 2007
Researchers developed an anatomical voxel model of an 89 kg woman at 30 weeks pregnancy to study low frequency field exposure. They calculated intracorporal electric current density distributions from homogeneous 50 Hz electric and magnetic fields and compared them to ICNIRP basic restrictions. The basic restriction was met in the mother's central nervous system at reference level exposure. However, the basic restriction was considerably exceeded in the fetus. The authors suggest revision of reference levels might be necessary.
Unknown authors · 2007
Researchers exposed UVW human glioma cells to ELF-EMF at 1 mT (50 Hz) for 12 hours. This exposure alone produced 0.011 mutations per locus per cell, a 3.75-fold increase over unexposed controls. ELF-EMF also increased the mutagenic effect of 0.3 Gy and 3 Gy gamma-irradiation by 2.6-fold and 2.75-fold respectively. The lower radiation dose of 0.3 Gy induced more than 10 times more mutations per unit dose than 3 Gy, indicating hypermutability at low dose.
Unknown authors · 2007
Researchers exposed Wistar rats to a 50 Hz, 1 mT magnetic field for either 4 hours (acute) or 4 hours per day for 45 days (long-term). Chromosomal aberration analysis showed no statistically significant differences between exposed and control groups. However, the long-term exposure group had a significantly higher micronucleus frequency than controls (p<0.01). Both acute and long-term exposure significantly reduced the mitotic index (p<0.001 and p<0.01) and the PCE/NCE ratio (p<0.001 and p<0.01).
