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PubMed2003

No effects of acute exposure to the electromagnetic field emitted by mobile phones on brainstem auditory potentials in young volunteers.

OBJECTIVES: A widespread use of mobile phones evokes a growing concern for their possible adverse effects on the human central nervous system. This study was aimed at evaluating the effects of EMF generated by mobile phones, at all standard wavelengths: 450, 935 and 1800 MHz used in Poland, on the auditory brainstem-evoked responses (ABR) during and after the exposure. MATERIALS AND METHODS: The effects of acute exposure to electromagnetic fields (EMF) on ABR were evaluated in 45 young, healthy volunteers of both genders. The electromagnetic impulses were generated with the antenna of mobile phone. The exposure was induced by repeated phone activation for 20 min. The ABR evaluation was performed before, during and immediately after the exposure, and the latencies of waves I, III and V, and inter-waves I-V were analyzed. RESULTS: Prior test calibration on a phantom did not show the influence of the external EMF generated by the mobile phone on the ABR equipment. For neither EMF frequency, differences were observed in wave and inter-wave latencies during and after exposure to EMF compared to the initial ABR pattern, in both men and woman. CONCLUSIONS: This implies that commonly used mobile phones do not affect propagation of electrical stimuli along the auditory nerve to auditory brainstem centers.

Adult↗
PubMed1997

Treatment with AC pulsed electromagnetic fields improves the response to levodopa in Parkinson's disease.

A 52 year old fully medicated Parkinsonian patient with severe disability (stage 4 on the Hoehn & Yahr disability scale) became asymptomatic 10 weeks after he received twice weekly transcranial treatments with AC pulsed electromagnetic fields (EMFs) of picotesla flux density. Prior to treatment with EMFs, his medication (Sinemet CR) was about 50% effective and he experienced end-of-dose deterioration and diurnal-related decline in the drug's efficacy. For instance, while his morning medication was 90% effective, his afternoon medication was only 50% effective and his evening dose was only 30% effective. Ten weeks after introduction of treatment with EMFs, there was 40% improvement in his response to standard Sinemet medication with minimal change in its efficacy during the course of the day or evening. These findings demonstrate that intermittent, AC pulsed applications of picotesla flux density EMFs improve Parkinsonian symptoms in part by enhancing the patient's response to levodopa. This effect may be related to an increase in the capacity of striatal DA neurons to synthesize, store and release DA derived from exogenously supplied levodopa as well as to increased serotonin (5-HT) transmission which has been shown to enhance the response of PD patients to levodopa. Since decline in the response to levodopa is a phenomenon associated with progression of the disease, this case suggests that intermittent applications of AC pulsed EMFs of picotesla flux density reverse the course of chronic progressive PD.

Antiparkinson Agents↗
PubMed2001

Effects of electromagnetic fields produced by radiotelevision broadcasting stations on the immune system of women.

The object of this study was to investigate the immune system of 19 women with a mean age of 35 years, for at least 2 years (mean = 13 years) exposed to electromagnetic fields (ELMFs) induced by radiotelevision broadcasting stations in their residential area. In September 1999, the ELMFs (with range 500 KHz-3 GHz) in the balconies of the homes of the women were (mean +/- S.D.) 4.3 +/- 1.4 V/m. Forty-seven women of similar age, smoking habits and atopy composed the control group, with a nearby resident ELMF exposure of < 1.8 V/m. Blood lead and urinary trans-trans muconic acid (a metabolite of benzene), markers of exposure to urban traffic, were higher in the control women. The ELMF exposed group showed a statistically significant reduction of blood NK CD16+-CD56+, cytotoxic CD3(-)-CD8+, B and NK activated CD3(-)-HLA-DR+ and CD3(-)-CD25+ lymphocytes. 'In vitro' production of IL-2 and interferon-gamma (INF-gamma) by peripheral blood mononuclear cells (PBMC) of the ELMF exposed group, incubated either with or without phytohaemoagglutinin (PHA), was significantly lower; the 'in vitro' production of IL-2 was significantly correlated with blood CD16+-CD56+ lymphocytes. The stimulation index (S.I.) of blastogenesis (ratio between cell proliferation with and without PHA) of PBMC of ELMF exposed women was lower than that of the control subjects. The S.I. of blastogenesis of the ELMF exposed group (but not blood NK lymphocytes and the 'in vitro' production of IL-2 and INF-gamma by PBMC) was significantly correlated with the ELMF levels. Blood lead and urinary trans-trans muconic acid were barely correlated with immune parameters: the urinary metabolite of benzene of the control group was only correlated with CD16+-CD56+ cells indicating a slight effect of traffic on the immune system. In conclusion, this study demonstrates that high frequency ELMFs reduce cytotoxic activity in the peripheral blood of women without a dose-response effect.

Adult↗
PubMed2003

Gravitational and electromagnetic fields near a de Sitter-like infinity.

We present a characterization of general gravitational and electromagnetic fields near de Sitter-like conformal infinity which supplements the standard peeling behavior. This is based on an explicit evaluation of the dependence of the radiative component of the fields on the null direction from which infinity is approached. It is shown that the directional pattern of radiation has a universal character that is determined by the algebraic (Petrov) type of the spacetime. Specifically, the radiation field vanishes along directions opposite to principal null directions.

Journal Article↗
PubMed2004

Negative-refractive bicrystal with broken symmetry produces asymmetric electromagnetic fields in guided-wave heterostructures.

Heterostructure arrangements of uniaxial bicrystals have been discovered to produce electromagnetic fields with asymmetric distributions in guide wave structures. The property behind this remarkable phenomenon is the broken crystalline symmetry which allows the new physics to be seen in unsymmetric distributions. Here the theory behind this phenomenon is presented, numerical calculations are performed using an ab initio anisotropic Green's function approach, and the results provided at 10 GHz for a realistic crystal system with nominal permittivity of 5. Asymmetric distributions seen here are one facet of the broken symmetry property which generates negative refraction for impinging waves on a bicrystal.

Journal Article↗
PubMed1997

[The present state of knowledge concerning the effect of electromagnetic fields of 50/60 Hz on the circulatory system and the autonomic nervous system].

Diseases of the circulatory system together with neoplastic diseases are recognised as the major health problem in the contemporary world. Their origin and aggravation may be related to the exposure to electromagnetic fields (EMFs) since theoretically, disorders in the functioning of the circulatory system are most likely due to electric impulses generated in it by external magnetic fields. The nervous system, including its autonomic part which regulates, among others, the functioning of the circulatory system, because of its electric nature is another system which may be disturbed by EMFs. From the 1960s, biological studies on the effects of power-line frequency EMFs have been carried out in many countries. In view of the applied study model, four main directions of these studies can be identified: in vitro and in vivo animal experiments, experimental studies on humans, clinical and epidemiological studies. Experimental studies on animals and humans have yielded ambiguous and very often contradictory results. Some of them indicate that EMF contributes to slowing down the cardiac rhythm and the stroke volume of the left ventricle, other results suggest their acceleration, and still other show no differences. The results of clinical studies performed in many countries in different groups of workers exposed to power-line frequency EMFs have not produced the evidence for drawing unequivocal conclusions. Again some studies reveal that those exposed show disorders in neurovegetative and blood pressure regulations (hypotension or hypertension) as well as in cardiac rhythm (bradycardia or tachycardia). Other studies do not confirm harmful effect of EMF on the circulatory system. Therefore, it is not feasible to find out, on the basis of these studies, whether and how chronic exposure to power-line frequency EMFs influences the functioning of the circulatory system, the more so as ECG standard recording has been to date the only diagnostic method, and according to the present state of knowledge it is not sufficient to assess the functioning of the circulatory system. Epidemiological studies play the most important role in the evaluation of health effects of the exposure to power-line frequency EMFs. These studies have been carried out for fifteen years, however, they do not consider the effect of chronic exposure to EMF of 50 Hz frequency on the circulatory system.

Animals↗
PubMed2003

Exposure of human peripheral blood lymphocytes to electromagnetic fields associated with cellular phones leads to chromosomal instability.

Whether exposure to radiation emitted from cellular phones poses a health hazard is at the focus of current debate. We have examined whether in vitro exposure of human peripheral blood lymphocytes (PBL) to continuous 830 MHz electromagnetic fields causes losses and gains of chromosomes (aneuploidy), a major "somatic mutation" leading to genomic instability and thereby to cancer. PBL were irradiated at different average absorption rates (SAR) in the range of 1.6-8.8 W/kg for 72 hr in an exposure system based on a parallel plate resonator at temperatures ranging from 34.5-37.5 degrees C. The averaged SAR and its distribution in the exposed tissue culture flask were determined by combining measurements and numerical analysis based on a finite element simulation code. A linear increase in chromosome 17 aneuploidy was observed as a function of the SAR value, demonstrating that this radiation has a genotoxic effect. The SAR dependent aneuploidy was accompanied by an abnormal mode of replication of the chromosome 17 region engaged in segregation (repetitive DNA arrays associated with the centromere), suggesting that epigenetic alterations are involved in the SAR dependent genetic toxicity. Control experiments (i.e., without any RF radiation) carried out in the temperature range of 34.5-38.5 degrees C showed that elevated temperature is not associated with either the genetic or epigenetic alterations observed following RF radiation-the increased levels of aneuploidy and the modification in replication of the centromeric DNA arrays. These findings indicate that the genotoxic effect of the electromagnetic radiation is elicited via a non-thermal pathway. Moreover, the fact that aneuploidy is a phenomenon known to increase the risk for cancer, should be taken into consideration in future evaluation of exposure guidelines.

Aneuploidy↗
PubMed2005

Effects of 900 MHz electromagnetic fields exposure on cochlear cells' functionality in rats: evaluation of distortion product otoacoustic emissions.

In recent years, the widespread use of mobile phones has been accompanied by public debate about possible adverse consequences on human health. The auditory system is a major target of exposure to electromagnetic fields (EMF) emitted by cellular telephones; the aim of this study was the evaluation of possible effects of cellular phone-like emissions on the functionality of rat's cochlea. Distortion Products OtoAcoustic Emission (DPOAE) amplitude was selected as cochlea's outer hair cells (OHC) status indicator. A number of protocols, including different frequencies (the lower ones in rat's cochlea sensitivity spectrum), intensities and periods of exposure, were used; tests were carried out before, during and after the period of treatment. No significant variation due to exposure to microwaves has been evidenced.

Animals↗
PubMed2000

A case of congenital pseudarthrosis of the tibia treated with pulsing electromagnetic fields. 17-year follow-up.

Congenital pseudarthrosis of the tibia presents surgeons with one of the most challenging of all orthopedic problems. Various surgical treatments have succeeded only rarely. We report long-term follow-up of a patient with congenital pseudarthrosis of the tibia treated with pulsed electromagnetic fields (PEMF) and bone grafting. In this severe case, Bassett type III and Boyd type II, encouraging results were achieved with Boyd's dual onlay grafts and PEMF. Seven years after surgery, skeletal maturity was complete and an unacceptable degree of leg shortening had been avoided.

Adolescent↗
PubMed2003

MAP kinase activation in cells exposed to a 60 Hz electromagnetic field.

This research provides evidence that mitogen-activated protein kinase or extracellular signal-regulated kinase (MAPK/ERK) is activated in HL-60 human leukemia cells, MCF-7 human breast cancer cells, and rat fibroblast 3Y1 cells exposed to a 60 Hertz (Hz), 1 Gauss (G) electromagnetic field (EMF). The effects of EMF exposure were compared to those observed using 12-O-tetradecanoylphorbal-13-acetate (TPA) treatment. The level of MAPK activation in cells exposed to EMF was approximately equivalent to that in cells treated with 0.1-0.5 ng/ml of TPA. A role for protein kinase C (PKC) in the process leading to MAPK activation in EMF exposed cells is also suggested by the results. MAPK activation is negated by an inhibitor to PKCalpha, but not PKCdelta inhibitors, in cells subjected to EMF exposure or TPA treatment. Thus, similarities between the effects of EMF exposure and TPA treatment are supported by this investigation. This provides a possible method for revealing other participants in EMF-cell interaction, since the TPA induction pathway is well documented.

Animals↗
PubMed1996

Effect of weak electromagnetic fields on body image perception in patients with multiple sclerosis.

Cerebellar ataxia is one of the most disabling symptoms of multiple sclerosis (MS) and also one of the least responsive to pharmacotherapy. However, cerebellar symptoms often improve dramatically in MS patients by brief, extracerebral applications of picotesla flux electromagnetic fields (EMFs). This report concerns two MS patients with chronic disabling ataxia who experienced rapid improvement in gait and balance after receiving a series of treatments with EMFs. To assess whether improvement in cerebellar gait is accompanied by changes in body image perception, a parietal lobe function, both patients were administered the Human Figure Drawing Test before and after a series of brief treatments with EMFs. Prior to application of EMFs these patients' free drawings of a person showed a figure with a wide-based stance characteristic of cerebellar ataxia. After receiving a series of EMFs treatments both patients demonstrated a change in body image perception with the drawings of the human figure showing a normal stance. These findings demonstrate that in MS improvement in cerebellar symptoms by pulsed applications of picotesla EMFs is associated with changes in the body image.

Adult↗
PubMed1998

Yawning and stretching--a behavioral syndrome associated with transcranial application of electromagnetic fields in multiple sclerosis.

Intracerebral administration of adrenocorticotropic hormone (ACTH) elicits in experimental animals a yawning stretching behavior which is believed to reflect an arousal response mediated through the septohippocampal cholinergic neurons. A surge in plasma ACTH levels at night and just prior to awakening from sleep is also associated in humans with yawning and stretching behavior. Recurrent episodes of uncontrollable yawning and body stretching, identical to those observed upon awakening from physiological sleep, occur in a subset of patients with multiple sclerosis (MS) during transcranial therapeutic application of AC pulsed electromagnetic fields of picotesla flux density. This behavioral response has been observed exclusively in young female patients who are fully ambulatory with a relapsing remitting course of the disease who also demonstrate a distinctly favorable therapeutic response to magnetic stimulation. ACTH is employed for the treatment of MS due to its immunomodulatory effects and a surge in its release in response to AC pulsed magnetic stimulation could explain some of the mechanism by which these fields improve symptoms of the disease.

Brain↗
PubMedDate not supplied

Electromagnetic fields in the treatment of postmenopausal osteoporosis: an experimental study conducted by densitometric, dry ash weight and metabolic analysis of bone tissue.

The authors conducted an experimental study on 32 female rats which had been castrated at 10 months of age in order to verify the ability of pulsating electromagnetic fields to prevent osteoporosis induced by surgical menopause. Two different values of intensity of PEMFs were used: 30 G and 70 G. After 4 months of treatment the following testing was done: monophotonic bone densitometry of the lumbar spine, quantitative measurement of the dry ash weight of the femurs, and hematochemical tests to evaluate bone metabolism. The experimental study showed that the PEMFs supplied at 30 Gauss were capable of slowing down the loss of bone mass, while the PEMFs supplied at 70 Gauss obstructed bone decay, providing values for Bone Mineral Density and dry ash weight which were very similar to those observed in the non-castrated control group. Hematochemical tests did not reveal significant variations between the two groups.

Animals↗
PubMed2000

[Activity of the genome of cardiomyocytes as an indicator of the development of adaptive changes in the myocardium following exposure of the central nervous system to electromagnetic fields].

Methods of cardiomyocyte nuclei isolation from the myocard homogeneous mixture, and of cardiomyocyte genome activity estimation were elaborated. In the experiments with hyperlipoproteidemic rats, cardiomyocyte genome activity was shown to reflect the primary adaptive changes in the myocard, and to serve a reliable index of their influence on the CNS regulatory centres exposed to electromagnetic field, which is used for hyperlipoproteidemia treatment. The cardiomyocyte genome activity was used to distinguish between three types of development of adaptive reactions in the myocard.

Animals↗
PubMed2006

1800 MHz electromagnetic field effects on melatonin release from isolated pineal glands.

Isolated pineal glands of Djungarian hamsters (Phodopus sungorus) were continuously perifused by Krebs-Ringer buffer, stimulated with the beta-adrenergic receptor agonist isoproterenol to induce melatonin synthesis, and exposed for 7 hr to a 1800 MHz continuous wave (CW) or pulsed GSM (Global System for Mobile Communications)-modulated electromagnetic signal at specific absorption rate (SAR) rates of 8, 80, 800, and 2700 mW/kg. Experiments were performed in a blind fashion. Perifusate samples were collected every hour, and melatonin concentrations were measured by a specific radioimmunoassay. Both types of signal significantly enhanced melatonin release at 800 mW/kg SAR, while at 2700 mW/kg SAR, melatonin levels were elevated in the CW, but suppressed in the GSM-exposed pineal glands. As a temperature rise of approximately 1.2 degrees C was measured at 2700 mW/kg SAR, effects at this level are thermal. With regard to radiofrequency electromagnetic fields, the data do not support the 'melatonin hypothesis,' according to which nonthermal exposure suppresses melatonin synthesis.

Animals↗
PubMed1996

Effects of 60 Hz electromagnetic fields on early growth in three plant species and a replication of previous results.

In an attempt to replicate the findings of Smith et al., seeds of Raphanus sativus L. (radish), Sinapsis alba L. (mustard), and Hordeum vulgare L. (barley) were grown for between 9 and 21 days in continuous electromagnetic fields (EMFs) at "ion-cyclotron resonance" conditions for stimulation of Ca(2+) (B(H) = 78.3 mu T, B(HAC) = 40 mu T peak-peak at 60 Hz, B(V) = 0). On harvesting, radish showed results similar to those of Smith et al. Dry stem weight and plant height were both significantly greater (Mann-Whitney tests, Ps < 0.05) in EMF-exposed plants than in control plants in each EMF experiment. Wet root weight was significantly greater in EMF-exposed plants in two out of three experiments, as were dry leaf weight, dry whole weight, and stem diameter. Dry root weight, wet leaf weight, and wet whole weight were significantly greater in EMF-exposed plants in one of three experiments. All significant differences indicated an increase in weight or size in the EMF-exposed plants. In each of the sham experiments, no differences between exposed and control plants were evident. Mustard plants failed to respond to the EMFs in any of the plant parameters measured. In one experiment, barley similarly failed to respond; but in another showed significantly greater wet root weight and significantly smaller stem diameter and dry seed weight at the end of the experiment in exposed plants compared to control plants. Although these results give no clue about the underlying bioelectromagnetic mechanism, they demonstrate that, at least for one EMF-sensitive biosystem, results can be independently replicated in another laboratory. Such replication is crucial in establishing the validity of bioelectromagnetic science.

Electromagnetic Fields↗
PubMed1994

Exposure to electromagnetic fields in operators of broadcast radio stations emitting at 737 kHz to 1602 kHz.

In Poland, 28 AM radio stations operate at frequencies from 738 kHz to 1602 kHz with output powers ranging from 1 kW to 750 kW. Altogether 384 workers are employed at those radio stations. Levels of exposure to electromagnetic fields (EMF) were identified at 5 of those radio stations, separately for 3 groups of workers, i.e. operation, maintenance, and administration. Electric and magnetic field intensities: E (in V/m) and H (in A/m), and the effective time of individual worker's exposure to EMF were assessed. The assessments were carried out independently by the conventional (MEH-1 plus stop-watch) and computer-aided (Holaday Programmable Recorder) methods. The study provided reliable data on the actual time of worker's exposure to EMF of exactly determined intensities. The study indicated a wide range of different exposure levels between individual groups of workers, which depended rather on a particular AM broadcast station and the type of job performed by individual groups of workers' than on the transmitter power or the type of protective zones in the vicinity of transmitters.

Electromagnetic Fields↗
PubMed1992

Effect of a pulsing electromagnetic field on demineralized bone-matrix-induced bone formation in a bony defect in the premaxilla of rats.

A 2-mm non-healing bony defect was prepared in the premaxilla of male Wistar rats weighing about 180 g as a simulation of an alveolar cleft, for determination of whether a pulsing electromagnetic field (PEMF) could promote regeneration of bone induced by demineralized bone matrix (DBM). The defect was either treated with 7 mg DBM or was left as a non-grafted control. The rats were exposed to a PEMF with a frequency of 100 Hz, a 10-ms-wide burst with 100 microseconds-wide quasi-rectangular pulses, repeating at 15 Hz, and magnetic field strength of 1.5-1.8 G. Alkaline phosphatase activity increased significantly from day 7 in the DBM-graft-plus-PEMF group and from day 10 in the DBM-graft group, reaching a maximum on day 14. A greater-than-two-fold rise in alkaline phosphatase activity and a three-fold rise in the amount of 45Ca incorporation in the DBM-graft-plus-PEMF group were attained compared with those of the DBM-graft group. The DBM-graft-plus-PEMF group produced more bone with almost complete osseous bridging in the defect sites than did the group treated with DBM only on day 35. The findings indicate that PEMF had an enhancing effect on the bone-inductive properties of the DBM through the stimulation of osteoblast differentiation induced by DBM.

Alkaline Phosphatase↗