EMF Research Studies

High magnetic field induced changes of gene expression in arabidopsis

Paul AL, Ferl RJ, Meisel MW · 2006

Gene expression analysis of ELF-MF exposed human monocytes indicating the involvement of the alternative activation pathway

Unknown authors · 2006

Researchers studied the cell activating capacity of extremely low frequency magnetic fields on human umbilical cord blood-derived monocytes. They confirmed previous findings that ELF-MF at 1.0 mT increased ROS release in human monocytes. Gene expression profiling using a whole-genome cDNA array was performed after 45 minutes of exposure. The exposure altered 986 genes involved in metabolism, cellular physiological processes, signal transduction, and immune response. Significant regulation was found for five genes, including IL15RA, EPS15R, DNMT3A, and DKFZP586J1624.

50-Hertz electromagnetic fields induce gammaH2AX foci formation in mouse preimplantation embryos in vitro

Unknown authors · 2006

Researchers investigated effects of electromagnetic fields on DNA damage in preimplantation mouse embryos using gammaH2AX foci formation as an indicator. EMFs decreased the cleavage rate of preimplantation mouse embryos. The decreasing effect was related to DNA damage shown by gammaH2AX foci formation. Noise magnetic fields or wortmannin inhibited the EMF-induced gammaH2AX foci formation. EMFs could activate the DNA damage-repair mechanism by recruiting Rad50 to damaged DNA sites.

Stimulation of ubiquitin-proteasome pathway through the expression of amidohydrolase for N-terminal asparagine (Ntan1) in cultured rat hippocampal neurons exposed to static magnetism

Unknown authors · 2006

Researchers screened genes responsive to brief magnetism in cultured rat hippocampal neurons using differential display analysis. They identified Ntan1 as a magnetism-responsive gene in rat brain. Northern blot analysis showed that Ntan1 mRNA increased about three-fold after 3 hours in response to brief magnetism. Brief magnetism induced degradation of MAP2 without affecting cell morphology or viability, and this degradation was prevented by a selective inhibitor of the 26S proteasome. Overexpression of Ntan1 using a recombinant adenovirus vector decreased MAP2 protein expression in hippocampal neurons.

Effects of pulsed electric fields on DNA of human lymphocytes

Unknown authors · 2006

Researchers investigated the effects of pulsed electric fields at 50 Hz on DNA of human lymphocytes using the comet assay. A significant amount of DNA damage was observed after exposure compared to controls. After 2 hours incubation at 37°C, a proportion of the damage was repaired. Hydrogen peroxide and gamma-irradiation increased the damage to lymphocytes exposed to pulsed electric fields according to the dose used, and the amount of repair was proportional to the damage.

Effects of subchronic exposure to static magnetic field on testicular function in rats

Unknown authors · 2006

Researchers exposed male adult rats to a static magnetic field of 128 mT for one hour per day over 30 days. Exposure did not change epididymal sperm count, sperm motility, or genital organ weight. Testicular and plasma testosterone levels decreased significantly in exposed rats. Oxidative stress markers malondialdehyde, metallothioneins, and 8-oxo-dG increased in the testis. Antioxidant enzymes CAT, GPx, and mitochondrial Mn-SOD decreased, while cytosolic CuZn-SOD activity was unchanged.

Pesticide induced DNA damage and its repair in cultured human cells

Unknown authors · 2006

Electromagnetic fields (900 MHz) evoke consistent molecular responses in tomato plants

Unknown authors · 2006

An in vitro study of the effects of exposure to a GSM signal in two human cell lines: monocytic U937 and neuroblastoma SK- N-SH

Unknown authors · 2006

Researchers exposed two human cell lines, neuronal SK-N-SH and monocytoid U937, to a 900 MHz RF signal pulsed at 217 Hz with a SAR of 0.2 W/kg. For SK-N-SH cells, they assessed effects using gene microarray, real-time PCR, Western blot for heat shock proteins, and flow cytometry for cell cycle and apoptosis. For U937 cells, they assessed effects using cell viability and cell cycle analysis. No significant difference was found between sham-exposed and radiofrequency-exposed cells in any assay or condition.

Lack of direct DNA damage in human blood leukocytes and lymphocytes after in vitro exposure to high power microwave pulses

Unknown authors · 2006

Researchers exposed human whole-blood leukocytes and isolated lymphocytes to high power microwave pulses at 8.8 GHz for 40 minutes in a rectangular waveguide. The average specific absorption rate was about 1.6 kW/kg with a peak of about 300 MW/kg, and the sample temperature rose by 3.5 ± 0.1 °C. No statistically significant DNA damage was found immediately after exposure or after a 30-minute incubation at 37 °C. The authors concluded that the pulses did not induce DNA strand breaks, alkali-labile sites, or incomplete excision repair sites detectable by the alkaline comet assay.

ROS release and Hsp70 expression after exposure to 1,800 MHz radiofrequency electromagnetic fields in three model cell lines.

Unknown authors · 2006

PMA treatment significantly increased ROS production in both cell types compared to sham or incubator controls. GSM-DTX exposure showed significantly different ROS production in monocytes compared to sham, but this was due to lowered ROS release during sham exposure. No ROS differences were detected in lymphocytes compared to sham or incubator control. Hsp70 expression in monocytes at 0, 1, and 2 hours post-exposure to GSM-DTX at 2 W/kg for 1 hour did not differ from incubator or sham controls.

Oxidative stress effects on the central nervous system of rats after acute exposure to ultra high frequency electromagnetic fields

Unknown authors · 2006

Researchers investigated the effect of acute UHF-EMF exposure on non-enzymatic antioxidant defense and lipid and protein oxidative damage in the rat frontal cortex and hippocampus. They used malondialdehyde (MDA) and carbonyl assays to assess lipid and protein oxidative damages, respectively. No changes in lipid and protein damage, and also in non-enzymatic defense were found in frontal cortex or hippocampus. The results suggest that acute UHF-EMF exposure is not able to produce detectable oxidative stress in rats from any age tested.

Light alters nociceptive effects of magnetic field shielding

Unknown authors · 2006

Orientation and pain sensitivity are affected by low-frequency magnetic fields near Earth's field strength. These effects often depend on visible light being present. Mice in a shielded dark environment showed altered nociception, but visible light during shielding eliminated most shielding effects.

Effects of 60-Hz magnetic field exposure on nocturnal 6-sulfatoxymelatonin, estrogens, luteinizing hormone, and follicle-stimulating hormone in healthy reproductive-age women: results of a crossover trial

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.

Consultations in primary care for symptoms attributed to electromagnetic fields--a survey among general practitioners

Unknown authors · 2006

Researchers conducted telephone interviews with a random sample of 342 Swiss general practitioners, achieving a 28.2% response rate. 69% of GPs reported at least one consultation due to EMF, with a median of three such consultations per year. The most commonly reported symptoms were sleep disorders, headaches, and fatigue, while the main suspected EMF sources were mobile phone base stations, power lines, and personal mobile phone use. GPs judged the association between EMF and symptoms as plausible in 54% of cases, but no specific symptom-source combination was consistently judged plausible.

Electrohypersensitivity: state-of-the-art of a functional impairment

Unknown authors · 2006

The aim of the studies was to investigate possible alterations in the cellular and neuronal systems of electrohypersensitive persons' skin. Age- and sex-matched persons without symptoms served as controls. Immunohistochemistry with antisera to previously characterized marker substances was used. Preliminary data indicate various alterations in the skin of electrohypersensitive persons.

The prevalence of symptoms attributed to electromagnetic field exposure: a cross-sectional representative survey in Switzerland

Unknown authors · 2006

Researchers conducted telephone interviews between May and June 2004 with a representative sample of 2048 Swiss residents aged over 14 years. The study found a 5% prevalence of electromagnetic hypersensitivity with a 95% confidence interval of 4% to 6%. Among those with electromagnetic hypersensitivity, the most common complaints were sleep disorders at 43% and headaches at 34%. 53 percent of the population were worried about adverse health effects from EMF without attributing their own health symptoms to them.

Do extremely low frequency magnetic fields enhance the effects of environmental carcinogens? A meta- analysis of experimental studies

Unknown authors · 2006

This paper is a meta-analysis of data from in vitro studies and short-term animal studies that have combined extremely low frequency magnetic fields with known carcinogens or other toxic physical or chemical agents. The data was analyzed by systematic comparison of study characteristics between positive and negative studies to reveal possible consistent patterns. The majority of the studies reviewed were positive, suggesting that magnetic fields do interact with other chemical and physical exposures. A nonlinear dose-response was found, showing a minimum percentage of positive studies at fields between 1 and 3 mT. The radical pair mechanism is a good candidate mechanism for explaining the biphasic dose-response seen in the analysis.

Childhood leukemia and residential magnetic fields: are pooled analyses more valid than the original studies?

Unknown authors · 2006

The comment was published in Bioelectromagnetics in December 2006. The authors are Kheifets, Mezei, and Greenland from the University of California, Los Angeles.

Effect of short-wave (6-22 MHz) magnetic fields on sleep quality and melatonin cycle in humans: the Schwarzenburg shut-down study

Unknown authors · 2006

Electromagnetic fields and female breast cancer

Unknown authors · 2006

Most epidemiological studies have indicated little or no overall effect of EMF exposure. But some early studies suggested effects among premenopausal women, particularly for estrogen receptor positive breast tumors. A recent very large occupational study with improved exposure assessment and enough statistical power also for subgroup analyses found no indications of increased risks in any subgroups. Most of the recent well-designed residential studies report no increased risks, and similar findings are reported in the majority of studies of bed heating devices.

A potential multiple resonance mechanism by which weak magnetic fields affect molecules and medical problems: the example of melatonin and experimental "multiple sclerosis"

Unknown authors · 2006

The hypothesis predicts optimal ameliorating effects on experimental allergic encephalomyelitis at derived intensities of about 35 and 70 nT and a frequency of 7 Hz. These predictions were congruent with prior rat experiments using magnetic field strengths of about 1-5000 nT at 0.5, 7, 40, or 60 Hz. The model proposes that weaker fields in the nanoTesla to picoTesla range would optimally affect micromolar melatonin concentrations and that mitochondrial proton gradients may be critical. The model offers an alternative explanation to variations of Faraday's Law and the Boltzmann constant that have been used to dismiss biological effects from weak magnetic fields.

Growth assessment of children exposed to low frequency electromagnetic fields at the Abu Sultan area in Ismailia (Egypt)

Unknown authors · 2006

Researchers conducted a cross-sectional study of 780 children aged 0-12 years in two areas of Ismailia, Egypt. The exposed group comprised 390 children living within 50 meters of high voltage power lines, and the control group comprised 390 children from another area. Standard anthropometric measurements and hand X-rays for bone maturation were performed. Exposed children showed significantly reduced head and chest circumferences and height at all ages, and a significant delay in carpal bone ossification.

Can EMF exposure during development leave an imprint later in life?

Unknown authors · 2006

Initial reports indicated that exposure of chicken eggs during embryonic development to power-line electric fields of 50 and 60 Hz at 10 V/m in air could cause the brain tissues of the hatched chickens to respond differently in a particular test. More recently, an anecdotal report of human sensitivity to EMF has appeared that shows a health-related influence of prior exposure history to particular power-line frequencies in chemically sensitized individuals. These reports open the question of whether the ambient electromagnetic environment can leave an imprint on developing organisms and if such imprint changes have the potential for health consequences.

Occupational magnetic field exposure and melatonin: interaction with light-at-night

Unknown authors · 2006

Researchers reanalyzed data from a previous study on 6-OHMS excretion in 60 women occupationally exposed to extremely low-frequency magnetic fields. Women were classified into four groups based on magnetic field exposure and light-at-night exposure. The group exposed to both magnetic fields and light at night had the lowest 6-OHMS excretion. The authors suggest that daytime magnetic field exposure may enhance the effects of nighttime light exposure on melatonin production.