Unknown authors · 2007
This 2007 study explains how humans and animals can actually hear microwave pulses, a phenomenon where electromagnetic waves create audible sounds inside the head. The research shows that pulsed microwaves heat tissue, creating pressure waves that travel through bone to the inner ear, where they're perceived as clicking or buzzing sounds. This finding has important implications for understanding exposure to wireless devices and MRI equipment.
Shirai T et al. · 2007
Pregnant F344 rats received a single dose of ENU on gestational day 18. Rats were exposed to a 1.95-GHz W-CDMA signal for 90 minutes a day, 5 days a week, for 104 weeks starting at 5 weeks of age. Brain average specific absorption rates were designed to be .67 and 2.0 W/kg for low and high exposures, respectively. The incidence and numbers of brain tumors in female rats exposed to 1.95-GHz W-CDMA signals showed tendencies to increase but without statistical significance, and overall no significant increase in incidences or numbers was detected in either males or females.
Chauhan V et al. · 2007
Researchers exposed human-derived cell lines TK6, HL60, and Mono-Mac-6 to intermittent 1.9 GHz pulse-modulated RF fields for 6 hours at SARs of 0, 1, and 10 W/kg. Cell viability, apoptosis, and cell cycle kinetics were measured immediately after exposure and 18 hours later. Cytokine expression (TNFA, IL1B, IL6, IL8, IL10, IL12) was also assessed. No detectable changes in cell viability, cell cycle kinetics, apoptosis, or cytokine expression were observed in any exposed group compared to sham controls. The positive heat-shock control showed decreased viability, increased apoptosis, and a G(2)/M cell cycle block.
Del Giudice E et al. · 2007
Italian researchers exposed human brain cancer cells to 50 Hz electromagnetic fields (the same frequency as European power lines) and found significantly increased production of beta-amyloid peptide, a toxic protein that accumulates in Alzheimer's disease. The overnight exposure at 3.1 millitesla didn't kill the cells but stimulated them to produce more of the harmful protein linked to dementia.
Del Giudice E et al. · 2007
Researchers tested whether low-frequency electromagnetic field exposure could affect amyloid-related processes in cultured cells. The study exposed H4 neuroglioma cells, which overexpress human mutant amyloid precursor protein, to a 3.1 mT 50 Hz electromagnetic field. Overnight exposure led to a significant increase in amyloid-beta peptide secretion, including the isoform Abeta 1-42, without affecting cell survival.
Unknown authors · 2007
Researchers crushed the sciatic nerves of rats and exposed them to electromagnetic fields at three different amplitudes plus a sham control. Whole-body exposure lasted four hours per day for five days using a solenoid coil that generated bipolar rectangular pulses at two pulses per second. Walking function was measured over 43 days by video recording the spread of toes one through five on the injured and uninjured hind limbs. No difference in toe-spread recovery appeared between any of the electromagnetic field treatments and the sham exposure.
Chauhan V et al. · 2007
Researchers examined the effect of RF field exposure on late onset gene expression in U87MG cells after a 24 h exposure period. A human monocyte-derived cell line (MM6) was exposed to intermittent RF fields for 6 h and gene expression was assessed immediately and at 18 h postexposure. Both cell lines were exposed to 1.9 GHz pulse-modulated RF fields for 6 or 24 h at SARs of 0.1-10.0 W/kg. The study found no evidence that nonthermal RF field exposure altered gene expression in either U87MG or MM6 cells relative to nonirradiated controls. Heat shock at 43°C for 1 h altered the expression of well-characterized heat-shock proteins in both cell lines.
Unknown authors · 2007
Carrubba S, Frilot C, Chesson AL, Marino AA. · 2007
Researchers exposed eight people to weak 60 Hz magnetic fields (1 gauss) for 2 seconds and measured their brain activity using specialized electrodes. They discovered that human brains can detect these low-level magnetic fields and respond in complex, nonlinear ways that standard testing methods miss. This suggests humans may have an evolutionary magnetic sensing ability that makes us vulnerable to artificial electromagnetic fields in our environment.
Unknown authors · 2007
Researchers measured electric current perception thresholds in self-declared EHS persons recruited from a self-aid group, newspaper responders, and persons seeking investigations. Quantitative electrosensitivity differed among the three recruitment groups. The self-aid group members overlapped considerably with the general population sample. Pooled EHS persons differed significantly from the general population but with pronounced overlap with the normal range.
Unknown authors · 2007
Schmid G et al. · 2007
A numerical model of the human middle and inner ear was developed at 0.1 mm resolution based on a real human tissue sample. The model was inserted into a commercial head model and FDTD computations were run for handheld device exposures from 400 to 3700 MHz. Highest absorption occurred at 400 MHz with 166 microW in the labyrinth and 12 microW in the vestibulocochlear nerve for a 500 mW device. For typical mobile phone frequencies (900 MHz and 1850 MHz) and output power values (250 mW and 125 mW), absorbed RF power was more than one order of magnitude lower than the values given above. The researchers concluded that temperature-related biologically relevant effects from typical handheld devices are unlikely.
Stevens P · 2007
Researchers studied whether exposure to a 0–5 µT magnetic field at EEG alpha-band frequencies (8–12 Hz) would affect emotional state. Participants reported a change in emotional state following exposure, and a decrease in global field power was observed. The frontal alpha-asymmetry that would physiologically indicate a directly induced emotional state was absent, and researchers suggested that participant experiences were due to an interpretation of the effects of MF exposure.
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.