Unknown authors · 2007
Researchers used the sister chromatid exchange technique to test the clastogenic potential of extremely low frequency electromagnetic fields on human peripheral blood lymphocytes. SCE frequencies were scored in dividing lymphocytes from six healthy male donors across two experimental rounds for reproducibility. Lymphocyte cultures were exposed to 50 Hz sinusoidal or square magnetic fields, continuous or pulsed, at 1 µT or 1 mT for 72 hours. A significant increase in SCEs per cell was observed in exposed groups compared to controls in both rounds. The highest SCE frequency in the first round was 10.03 for a square continuous field, and 10.39 for a square continuous field was the second highest in the second round.
Clark ML et al. · 2007
Researchers measured estrogen and melatonin metabolites in overnight urine from women living near radio and television transmitters. Among premenopausal women, no associations were found between RF or 60-Hz exposure and either metabolite.
Stevens P. · 2007
Researchers exposed people to weak magnetic fields similar to those from household appliances and found participants reported emotional changes. Brain scans revealed these feelings weren't from direct brain effects, but from people noticing subtle physical sensations, showing how weak fields can indirectly influence mood.
Canseven AG, Keskil ZA, Keskil S, Seyhan N. · 2007
Researchers tested whether a 50 Hz, 0.2 mT magnetic field given before or after drug administration affected seizures induced by pentylenetetrazol in mice. The magnetic field was generated by a pair of Helmholtz coils and seizures were induced by intraperitoneal injection of pentylenetetrazol at 60 mg/kg. Forty-eight adult female mice were used and latency to seizure, total seizure duration, and mortality were recorded. Neither pre- nor post-drug magnetic field exposure had any effect on seizures or mortality rates.
Canseven AG, Keskil ZA, Keskil S, Seyhan N. · 2007
Researchers tested whether 50 Hz magnetic fields (the type from power lines) could affect seizures in mice, either making them better or worse. They exposed mice to magnetic fields before and after giving them a seizure-inducing drug, measuring how quickly seizures started and how long they lasted. The magnetic field exposure had no effect on seizures whatsoever, suggesting these fields don't influence brain seizure activity at the levels tested.
Ishay JS et al. · 2007
Researchers kept Oriental hornet workers in an Artificial Breeding Box and exposed them to an AC magnetic field of a magnitude of B = 50-70 mGauss, comparing the combs they built with those from a control group exposed only to the natural terrestrial magnetic field. Exposed hornets built combs with a 35-55% smaller number of cells and fewer eggs, many deformed and imperfectly hexagonal cells, and more delicate and slender comb stems.
Wang KJ, Yao K, Lu DQ. · 2007
Calota V, Dragoiu S, Meghea A, Giurginca M. · 2007
The study evaluated the effects of 50 Hz magnetic fields at different intensities on chemiluminescence intensity of human serum. Exposure for 1 and 2 h increased chemiluminescence emission, and adding prooxidants FeCl(2) and H(2)O(2) in different concentrations increased chemiluminescence intensity even more.
Carrubba S, Frilot C, Chesson AL, Marino AA. · 2007
Che Y, Sun H, Cui Y, Zhou D, Ma Y. · 2007
Researchers examined the effects of a 50 Hz magnetic field at 1 mT intensity on learning and memory in Lohmann brown domestic chicks using a detour learning task. Chicks exposed for 20 hours per day showed a significant impairment in detour learning, while those exposed for 50 minutes per day showed no effect.
Del Giudice E et al. · 2007
Researchers tested whether low-frequency electromagnetic field exposure could affect amyloidogenic processes in cultured cells. They exposed H4 neuroglioma cells that stably overexpress human mutant amyloid precursor protein to a 3.1 mT 50 Hz field. Overnight exposure significantly increased secretion of amyloid-beta peptide, including the isoform Aβ 1–42, without affecting cell survival.
Jadidi M et al. · 2007
Researchers used a water maze to evaluate how magnetic field exposure affects consolidation and retrieval of spatial memory in rats. Exposure to a 50 Hz, 8 mT magnetic field for 20 minutes immediately after training impaired retention performance, but exposure at 2 mT did not. Exposure given shortly before retention testing had no effect on performance.
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.
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
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.