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1.
High frequency electromagnetic fields (EMF) are widely used for transmitting of radio and TV signals, in wireless communications,
etc. A huge number of people are exposed so the possible risk to human health from telecommunication technologies could be
significant even if biological effects are slight. The study of the biological effects of RF EM radiation could contribute
to better understanding of the possible health hazards. The levels of released hemoglobin serve as an indicator of hemolysis,
caused by increased membrane fragility. This study was designed to investigate the alterations in hemoglobin release after
in vitro exposure of human erythrocytes to GSM900 electromagnetic field. Erythrocyte suspensions with two different cell concentrations
(hematocrit 20% and 40%) were exposed to EM radiation from GSM mobile phone (carrier frequency 902 MHz, 2 W output power in
pulse) for 20 min in two different positions in relation to telephone antenna: Position 1 is in the centre of the major lobe
of the azimuth antenna pattern and Position 2 is between major and back lobes. Alterations in hemolysis were registered 0,
10, 20, 30, 40, 50 and 60 min after the treatment. Hemolysis was determined by measuring the absorbance of hemoglobin at 413 nm
in the supernatant obtained by centrifuging the suspensions. Hemolysis was expressed as hemoglobin concentration. Our data
indicated decrease in the hemoglobin level in irradiated suspensions. The GSM900 EMF exposure probably stabilized erythrocyte
membrane and caused reduction in the hemolysis depending on the EMF parameters, on the suspension water content (hematocrit)
and on the time elapsed after irradiation. 相似文献
2.
Y. R. Mikayelyan N. S. Baghdasaryan A. K. Nikoghosyan S. V. Barseghyan S. N. Ayrapetyan 《The Environmentalist》2012,32(2):179-187
The effects of extremely low-frequency electromagnetic field (ELF EMF) and ELF-modulated millimeter waves (MMW) on physicochemical
properties of physiological solution (PS) at different environmental medium were studied. The existence of frequency “windows”
at 4 Hz and 8 Hz frequencies of ELF EMF and ELF-modulated MMW which have different effects on heat fusion period (HFP), hydrogen
peroxide (H2O2) formation and oxygen (O2) content of water solution and different dependency on temperature, background radiation (BGR) and illumination was shown.
The obtained data allow us to suggest that cell bathing medium serving as a target through which the biological effects of
ELF EMF and ELF-modulated MMW on cells are realized is extra sensitive to environmental factors. Therefore, the variability
of experimental data on EMF biological effects, obtained in different laboratories can be explained by different environmental
conditions of experiments, which very often are not considered adequately. 相似文献
3.
Lyubina Vesselinova 《The Environmentalist》2012,32(2):249-255
The importance of the assessment of the electromagnetic fields /EMF/ background as a health risk factor for the physiotherapy
personnel is discussed in this paper. Wide frequency and amplitude ranges as well as large variety of design prescribed in
the rehabilitation program form complicated work conditions. In this paper, we attempt to present and classify this specific
work environment, i.e., low intensive EMF background with non homogenous frequency and modulation characteristics, stochastic
changes running during day, ground or even underground units’ placement and professional specifics, i.e., chronic EMF expositions,
personnel’s trunk and hands exposure, dose-measurement absence, lack of program for prevention and prophylaxis for the assessment
of the relatively insufficiently elucidated potential of EMF as a harmful factor for medical staff. Our “Study of the biological
effects of the EMF among medical staff from PRM wards—potential of risk reduction”/initialized in 1999/and the original survey
card structure are presented in general here first. It has been shown the importance to extend the “native” studies among
homogenous professional groups, two of them presented there, as well as the study of the biological effects of EMF in their
different aspects, especially taking into account the elevated levels of ionizing and non-ionizing radiation in the environment.
This includes the special attention on the exposure of medical staff from PRM units and creation of adequate methods for prevention
of unnecessary exposure to these physical factors. 相似文献
4.
Marko S. Markov 《The Environmentalist》2009,29(2):169-176
During the last three decades the interest toward clinical application of magnetic and electromagnetic stimulation increased
worldwide. Numerous publications have discussed the possibility of exogenous magnetic fields to initiate beneficial effects
on various biological processes, which are of critical importance for healing of different injuries and pathologies. Today,
magnetic and electromagnetic fields are increasingly utilized for the treatment of numerous musculoskeletal injuries and pathologies.
For example, selected magnetic fields were reported to be beneficial in the treatment of musculoskeletal injuries and post-surgical,
post traumatic and chronic wounds, reduction of edema, in the acceleration of pain and stress relief, and thus contribute
to healing processes. The application of this modality could be facilitated by establishing the exact dosimetry of application
and by searching for biophysical mechanisms of action, as well. It should be remembered that “not all magnets are equal”,
therefore the specific medical problem requires a proper diagnostics, a selection of the magnetic field to be applied and
a design of the appropriate protocol for treatment. The paper advised that every study and report should carefully explain
both the medical problem and the parameters of the applied magnetic field and cautions against generalized statements like
“Magnetic field does/does not cause biological response”. 相似文献
5.
This article highlights recent research on the beneficial use of selected low frequency electromagnetic fields (EMF) as a
safe alternative therapy for treatment of cancer and other health problems. It is shown that EMF therapy provides a safe alternative
and adjunct modality for the treatment of cancer and other health problems, and therefore, research in this field deserves
more support. The paper also discusses some reports and hypothesis of potential risk of human exposure to low frequency EMF,
mainly to the power line frequency of 60 Hz. 相似文献
6.
Gabi N. Waite Stéphane J. P. Egot-Lemaire Walter X. Balcavage 《The Environmentalist》2011,31(2):107-113
Over the past decades, strong evidence has accumulated that low-frequency electromagnetic fields (EMFs) can be useful in treating
human pathologies, such as bone fractures, soft tissue illnesses, and pain. Common strategies for the design of commercial
therapeutic devices are to generate EMFs that simulate body endogenous EMFs, or EMFs that resonate with a particular biological
process, such as the natural motions of ions. We recently came across a biologically active commercial EMF signal that seems
to be different. The signal is generated by summing the fundamental frequencies and harmonics of several periodic base signals
which remain proprietary to the company. When first examined in the time domain, the signal resembled electronic noise; however,
when critically analyzed, the signal is not identical with noise. Rather, it is a highly complex waveform exhibiting a very
wide range of values for the time derivative of the magnetic field density (dB/dt) and a beat frequency in the Extremely Low-Frequency
range. In this paper, we speculate on the mechanism of action of this and similar signals. We consider it less likely that
cells, or cell components, act like filters to extract and couple with individual signals that make up the complex EMF signal.
Consequently, we favor the possibility that with the signal discussed here cells respond to the very complex signal and that
the biological response can be modified by the presence of a beat in the signal, in this case a low-frequency beat. More generally,
this would suggest the hypothesis that biological processes can be regulated by noise-like signals and that the effects of
a noisy signal can be modified by the presence of signal repetition patterns, such as beats. Given the very small energy that
signals like these can transduce into a biological system, biological effects can be expected only when the molecular processes
involved are poised so that the available energy leads to molecular reactions that achieve the activation state for the reaction. 相似文献
7.
Although the biological effect of non-ionizing (NIR) and ionizing radiation (IR) on plant seed potential is well documented,
the mechanism of this impact is not clear yet. Since cell hydration, a fundamental parameter for determining cell function,
is magneto-sensitive, in present work, a comparative study of extremely low frequencies (ELF) electromagnetic field (EMF),
ELF EMF-modulated millimeter waves, and radiation exposure effects on winter wheat seeds water absorption and dry mass changes
was performed. The seeds were incubated in physiological solutions (PS) for 2 and 72 h. In case of 2-h incubation, the water
absorption determined by osmotic gradients between seeds and bathing medium, PS treated by all these factors leads to changes
of water absorption. While in case of 72-h incubation (when germination processes are in active state) these impact had reversed
character. The obtained data strongly suggest seeds bathing medium as a target through which the biological effects of NIR
and IR are realized. 相似文献
8.
Marko S. Markov 《The Environmentalist》2007,27(4):457-463
The interest toward clinical application of magnetic and electromagnetic stimulation increases worldwide. Numerous publications
discussed the possibility exogenous magnetic and electromagnetic fields to initiate effects on various biological processes,
which are of critical importance for healing of different injuries and pathologies. Today, magnetic and electromagnetic fields
are increasingly utilized for treatment of various musculoskeletal injuries and pathologies. For musculoskeletal injuries
and post-surgical, post traumatic and chronic wounds, reduction of edema is a major therapeutic factor in the acceleration
of pain and stress relief, and thus contribute to healing processes. Electromagnetic and magnetic fields appear to be unique
in their safety during clinical use. The application of this new modality will be facilitated by searching for biophysical
mechanisms of action as well as by establishing exact dosimetry of application. In that respect basic science research needs
to be developed in parallel with clinical applications. Magnetotherapy provides a non-invasive, safe, and easy method to directly
treat the site of injury, the source of pain and inflammation, and other types of injury. Unfortunately, there are many obstacles
that magnetotherapy has to overcome—both from the mainstream medicine as well as from the manufacturers and distributors of
magnetic devices. The physical principle of magnetism as well as the physiological bases for the use of magnetic field for
tissue repair are subjects of this review. 相似文献
9.
John A. Robertson Alex W. Thomas Julien Modolo Jodi Miller Nicole Juen Alexandre Legros Frank S. Prato 《The Environmentalist》2011,31(2):134-139
The field of bioelectromagnetics, consisting of the study of the interaction between electromagnetic fields and biological
systems, has been rapidly expanding in the recent years. One important factor that contributes importantly to the development
of this field is the continuing advances in technology allowing researchers to investigate different endpoints, or to more
precisely measure changes, if any. Hybrid functional imaging is a rapidly maturing field that opens new, important horizons
for bioelectromagnetics research. Indeed, unraveling the interaction mechanisms of electromagnetic fields on biological systems
(with an emphasis on the brain) requires a monitoring of electrical, functional, and metabolic activity of living tissue at
different temporal and spatial scales. Individual tools (e.g., electroencephalography, EEG; functional magnetic resonance
imaging, fMRI) are limited in their ability to detect the effects of electromagnetic interaction at specific temporal and
spatial scales, so combining these imaging methods offers a unique opportunity to provide a more comprehensive view of effects
in living tissue. In this paper, we will present the different imaging techniques that are available to bioelectromagnetics
researchers, including their capabilities and how they are complemented by simultaneous hybrid imaging. Future possibilities
of hybrid imaging technologies are discussed. 相似文献
10.
Marko S. Markov 《The Environmentalist》2011,31(2):89-96
Natural and man-made magnetic and electromagnetic fields are important factors in the contemporary life. The paper discusses
the role of environmental magnetic and electromagnetic fields in origin and evolution of life. A brief review of the characteristics
of Earth magnetic field, Earth magnetosphere, and their role as a shield for cosmic radiation follows. The role of endogenous
and exogenous magnetic fields is discussed in respect of the clarification of the potential hazard and benefit of electromagnetic
fields. The second part of the paper discusses the mechanisms of detection and response to exogenous electromagnetic fields,
as well as threshold versus window hypothesis for mechanisms of interactions. Finally, the necessity of accurate dosimetry
at the target site and the importance of relevant research and clinical protocols in studying biological responses are pointed
out. 相似文献
11.
Chiyoji Ohkubo Hideyuki Okano Akira Ushiyama Hiroshi Masuda 《The Environmentalist》2007,27(4):395-402
Authors review the importance of studying the effects of electromagnetic fields (EMF) on microcirculatory system, especially
in respect of possibility that vasculature may have direct and indirect role in interaction of static magnetic fields (SMF).
We outline the physiological importance of microcirculation and relatively new methods of evaluation technique in vivo and
explain in details the local and/or whole body exposure effects of SMF with␣range of 0.3–180 mT, power frequency EMF with
range of 0.1–30 mT and microwaves at 1.5 GHz with range 0.08–8 W/kg brain average specific absorption rate (SAR) on microcirculatory
systems in different tissues in experimental animals. 相似文献
12.
Summary Despite of decades of successful worldwide use of magnetic/electromagnetic field therapy, the answer to the question of possible
mechanisms of action is still lacking. Scientific reports of successful therapeutic use of magnetic/electromagnetic fields
are worldwide; however, our understanding of the underlying mechanism is limited. This paper presents a new hypothesis that
therapeutic benefit of magnetic fields might result from effects that originated on the level of important systems in human
body. It is known now that the life is an electromagnetic event in aqueous medium. Therefore, an appropriate choice of magnetic
and/or electromagnetic field may be expected to initiate systemic changes that result in efficacious effects distant from
the point of application. Observations of this phenomenon have been reported in at least two forms: (1) neutralization of
the pain experience distant to the point of magnetic field exposure; and, (2) various alterations of T-lymphocytes in response
to pain and to magnetic fields. Extrapolating these observations to the level of blood-vessel system, one might hypothesize
that a “healthy” cell does not respond as readily to the applied fields as do abnormal cells (which are in a disease or injury
state). 相似文献
13.
Yury Grigoriev 《The Environmentalist》2012,32(2):193-200
Today world population lives in a new electromagnetic environment, characterized with (i) around the clock enforcement of
chronic exposure of all age and gender groups to a wide range of modulated electromagnetic fields (EMF) from base stations;
(ii) daily, repeated from early childhood throughout entire life exposure to EMF RF mobile phone the brain and vestibular
receptor apparatus and auditory analyzers, located directly “under the EMF beam” in the inner ear. On the other hand, the
world science and epidemiology is missing well-planned and executed research results of prolonged exposure of EMF RF on the
brain. International recommendations and domestic guidelines do not include changing conditions of RF EMF on the population:
the brain has become a critical organ, and the children entered the risk group. The population continues to actively use the
mobile phone. In this situation the problem of assessing the risk of mobile communications has become a social and ethical. 相似文献
14.
L. R. Yeganyan R. E. Muradyan F. H. Arsenyan G. K. Bazikyan S. N. Ayrapetyan 《The Environmentalist》2012,32(2):236-241
There are many data about the extremely low-frequency electromagnetic fields (ELF-EMF) therapeutic use, especially in the
field of oncology. Recent data suggest that 4 Hz EMF having dehydration effect on tissues has a pronounced antitumor activity
on sarcoma-180 in mice. It was shown that 4 Hz EMF have pronounced effects on physicochemical properties of water and water
solution. Therefore, the aim of the present work was the comparative study of the modulation effect of ELF-EMF on cisplatin-induced
changes cell hydration and number of ouabain receptors in membrane of sarcoma-180 tumor tissues. Tissue hydration was measured
as wet weight/dry weight and expressed as a water content of g/g in dry weight. The number of 3H-ouabain receptors in membrane was counted by isotope scintillation counter. In conclusion, ELF-EMF can be a possible tool
for stimulation of cisPt antitumor effect. 相似文献
15.
Summary In an effort to explain the benefit of therapeutic use of electromagnetic fields (EMF) a systemic effect has been proposed
by us. To assess the efficacy of this approach, an objective biochemical approach was developed. Ten patients with Reflex
Sympathetic Dystrophy (RSD) were clinically evaluated, and lymphocytes were isolated from their blood samples obtained before
and after exposure of the uninvolved limb to an EMF. Utilizing a SpectraCell method that includes radio labeled molecules
and protein-free media for culturing the lymphocytes, an elevation of the content of fructose, serine, glycine, and calcium
cellular metabolic uptake were found following in the culture to EMF in comparison with non-exposed lymphocytes (p < 0.01). In addition, the pain level was determined by a conventional visual analogue scale (VAS) before and after EMF exposure,
evidencing a significant pain relief. Specifically, after exposure to 120 pps semi sinewave, 1500Gauss EMF, generated by a
THERAMAG∘ledR device, an improvement in the flexibility of the limb and a reduction in swelling of the affected extremity were detected
clinically. These findings are in concert with the new hypothesis that, with relief of pain, lymphocytes are predominately
altered in their cell cycle from M phase to S phases associated with increased structuring of intracellular water. A consideration
of the basic understanding of the role lymphocytes may be inferred from this preliminary study. An extensive review of the
literature on the basic science and therapeutic use of magnetic fields in humans is provided in an attempt to understand the
relevance of magnetic therapy of specific pain syndromes. 相似文献
16.
In the recent years concerns whether exposure to electromagnetic fields (EMF) from base station antennae can cause adverse
health effects are grown. Great attention is paid on risk of EMF exposure to people living in a close proximity of base stations.
In this issue, a point of interest is the personnel mounting, adjusting and maintaining base stations. Their working tasks
require stay in high EMF levels’ conditions. There are only few studies concerning this specific occupational group. The results
from our previous investigation (Zaryabova and Israel 2006) show that in␣many cases on performing some specific tasks operators
are overexposed according to our national legislation, and ICNIRP guidelines. Here, we present an extended study covering
more base stations and more precise scenario for performed tasks and working positions. Results of exposure assessment are
presented. They include energetic load calculations on the basis of Bulgarian national legislation, and the corresponding
SAR values. Data are used to determine permissible time duration for each particular work operation and served as a base for
limiting the exposure and proposal for protective measures for the personnel. 相似文献
17.
Varsik Martirosyan Levon Markosyan Hrachik Hovhanesyan Karlen Hovnanyan Sinerik Ayrapetyan 《The Environmentalist》2012,32(2):157-165
The aim of this work was to investigate the frequency-dependent effects of extremely low-frequency electromagnetic field (ELF-EMF)
and mechanical vibration at infrasound frequency (MV at IS frequency or MV) on growth and development of Escherichia coli K-12, by using classical microbiological (counting colony forming units), isotopic, spectrophotometric and electronmicroscopic
methods. The frequency-dependent effects of MV and ELF-EMF were shown that they could either stimulate or inhibit the growth
and the division of microbes depending on the periods following exposure. However, the mechanism through which the MV and
ELF-EMF effects affect the bacteria cell is not clear yet. It was suggested that the aqua medium could serve a target through
which the biological effect of MV and ELF-EMF on microbes could be realized. To check this hypothesis, the frequency-dependent
effects (2, 4, 6, 8, 10 Hz) of both MV and ELF-EMF on the bacterial growth, division and their motility in cases of exposure,
the preliminary treated microbes-free medium and microbes containing medium were studied. Both MV and ELF-EMF effect on microbes
have frequency and post-exposure period duration-dependent characters. The [
3
H]-thymidine involving experiments shown that EMF at 4 Hz exposure has pronounced stimulation effect on cell proliferation while 4 Hz
MV has inhibition effect. But at 8–10 Hz, the both EMF and MV have inhibitory effects on cell proliferation. It is suggested
that 4 and 8 Hz EMF have different biological effects on microbes. 相似文献
18.
In the recent years concerns whether exposure to electromagnetic fields (EMF) from base station antennae can cause adverse
health effects are grown. Great attention is paid on risk of EMF exposure to people living in a close proximity of base stations.
In this issue, a point of interest is the personnel mounting, adjusting and maintaining base stations. Their working tasks
require stay in high EMF levels’ conditions. There are only few studies concerning this specific occupational group. The results
from our previous investigation (COST 281—Graz, 2006) show that in many cases on performing some specific tasks operators
are overexposed according to our national legislation, and ICNIRP guidelines. Here, we present an extended study covering
more base stations and more precise scenario for performed tasks and working positions. Results of exposure assessment are
presented. They include energetic load calculations on the basis of Bulgarian national legislation, and the corresponding
SAR values. Data are used to determine permissible time duration for each particular work operation and served as a base for
limiting the exposure and proposal for protective measures for the personnel. 相似文献
19.
The new recommendations of WHO and EC for legislation in Europe and other countries concerning non-ionizing radiation (NIR)
health and safety include exposure limits that are very debatable. ICNIRP Guidelines propose exposure limits for electromagnetic
fields in the frequency range up to 300 GHz based on short-term exposures and on thermal effects. The new EC proposal for
optical and laser safety legislation includes classification of sources of radiation—both lasers and other optical sources,
but not requirements for the methodology of classification. On the other hand, many new requirements have been set by the
WHO publication “Model Legislation for EMF Protection” concerning the responsibilities in the field of EMF health and safety.
Many specialists in the field of developing exposure limits have positions very far away from the proposed of the ICNIRP Guidelines
philosophy. The results are different approaches in developing standards and exposure limits, and differences more than 100
times in maximal permissible levels. We, the Bulgarian Program Committee on NIR, try to organize working groups and discuss
different philosophy for developing exposure limits for more than 10 years. This paper exposes our position in this area. 相似文献
20.
On experimental setup in bioelectromagnetics 总被引:1,自引:1,他引:0
Bioeffects created by electromagnetic field (EMF) are the subject of intensive studies. This paper critically considers estimations
of exposure to EMF in bioelectromagnetic experiments. Results of calculations presented herein show the significant role of
the presence of conducting bodies (the exposure system) near an object under test on EMF energy absorption as well as mutual
interactions between simultaneously exposed objects. Our aims herein are twofold: firstly to find a way to refer measurement
results to free-space conditions in order to enable comparison of results obtained in different laboratories, and secondly
to show that EMF energy absorption in any exposed object is different and that this difference is a function of the size of
the exposure system, the number of exposed objects, and the particular properties (i.e., the electromagnetic structure) of
the objects. In the authors’ opinion the existence of interactions caused by the presence of the exposure system and other
exposed objects is a reason why remarkable differences are observed between experiments performed even under supposedly identical
conditions. The presented considerations and conclusion suggest wider participation of physicists and engineers in bioelectromagnetic
experiments in order to ensure the correctness of metrological aspects of these experiments. 相似文献