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1.
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
2.
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
3.
Electromagnetic field sources used for communication always have been subject of serious interest. There are many publications
concerning exposure and risk assessment of the working in such environment. Results of epidemiological study performed in
Bulgaria in the 1990's show exceeding of the maximal permissible values especially in radio stations for the personnel in
24 h working shift [Israel et al. (1992). Study of the electromagnetic in its influence on personnel working in radio and
TV stations, Report, National Centre of Hygiene, Medical Ecology and Nutrition; Israel and Tomov (2001). Epidemiological study
of the effects of radiofrequency radiation on operators in radio, TV and relay stations, Proceeding of the Eastern European
Regional Meeting and Workshop “Measurements and Criteria for Standard Harmonization in the field of EMF Exposure” and WHO
EMF Standards Harmonization Meeting, Varna, Bulgaria, 28 April—3 May, 2001, pp.145–153]. In the last years the situation is
strongly influenced by the development of the technology which leads to changes in equipment in radio and TV stations, using
lower power, facilitate the working regime. The paper presents data of exposure assessment of different professional groups
in selected radio and TV stations. Assessment is being performed on basis of EMF parameters values and energetic load calculations
according to the national legislation. Data are compared with the results of previous investigation to evaluate the new situation
in this branch. Exposure levels are much lower than those in the previous study, and lower compared to the exposure limits,
as well [Israel et al. (1992). Study of the electromagnetic in its influence on personnel working in radio and TV stations,
Report, National Centre of Hygiene, Medical Ecology and Nutrition; Israel and Tomov (2001). Epidemiological study of the effects
of radiofrequency radiation on operators in radio, TV and relay stations, Proceeding of the Eastern European Regional Meeting
and␣Workshop “Measurements and Criteria for Standard Harmonization in the field of EMF Exposure” and WHO EMF Standards Harmonization
Meeting, Varna, Bulgaria, 28 April—3 May, 2001, pp.145–153]. 相似文献
4.
ICNIRP于2020年3月出版了2020年版《限制电磁场暴露的导则(100 kHz~300 GHz)》,为了准确掌握2020版导则在基本限值和导出限值方面与旧版导则的差异,通过对比新旧导则对应条款得到具体变化情况。2020版导则修订了全身暴露基本限值与导出限值、局部暴露基本限值、神经刺激基本限值、肢体感应电流导出限值,增加了局部暴露导出限值、短暂局部暴露基本限值与导出限值,删除了微波听觉效应基本限值、接触电流导出限值。2020版导则更新了限制射频电磁场暴露的科学基础,使限值更加匹配近年来的科学研究成果,提升了导则的科学性、严谨性和准确性。 相似文献
5.
Martino Grandolfo 《The Environmentalist》2009,29(2):109-117
Over the last years, a wide debate has developed on the possible health effects of exposure to electromagnetic fields. In-depth
research activity was therefore developed by the international scientific community aimed at evaluating the risk associated
with exposure to this type of radiation. At the same time, various international institutions began to issue recommendations
on exposure limits valid for workers and for the population in the frequency range up to 300 GHz. Most of the recently revised
safety standards worldwide are set in terms of internal rates of electromagnetic energy deposition (Specific Absorption Rate)
at radiofrequency and microwave frequencies, and of induced electric fields or current densities at lower frequencies up to
10 MHz. At the international level, the most authoritative guidelines have been developed by the International Commission
on Non-Ionizing Radiation Protection (ICNIRP); another internationally well recognized standard is that developed by the Institute
of Electrical and Electronics Engineers (IEEE) in the USA, adopting the same basic approach of ICNIRP, although with some
differences in numerical values.
This article is mainly focused on the analysis of different approaches for the protection against electromagnetic fields,
and on the rationale of most relevant standards. 相似文献
6.
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
7.
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
8.
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
9.
An ensemble of thirty physico-chemical characteristics was used to assess the quality of well waters in four urban centers
in southern Nigeria: Lagos, Benin City, Warri, and Ekpoma. The characteristics investigated include pH; color; turbidity;
salinity; electrical conductivity, EC; total dissolved solids, TDS; total suspended solids, TSS; dissolved oxygen, DO; total
hydrocarbon, THC; biochemical oxygen demand, BOD; chemical oxygen demand, COD; and nitrate, nitrite, ammonia, sulfate, and
phosphate concentrations. Also monitored were the concentrations of sodium, calcium, potassium, magnesium, chloride, bicarbonate,
iron, lead, copper, manganese, zinc, chromium, nickel, and cadmium. The results obtained were compared with World Health Organization,
WHO, and Nigerian Federal Ministry of Environment, FME, drinking water standards. The results show that with the well water
obtained from Lagos, turbidity, 11.80 NTU; pH, 5.68; EC, 1065.55 μS/cm; TDS, 539.00 mg/L; concentrations of iron, 1.83 mg/L;
manganese, 0.14 mg/L; and lead, 1.35 mg/L did not meet the WHO standards. In Warri, pH, 5.19; concentrations of lead, 1.35 mg/L;
and chromium, 0.10 mg/L in the well water were above the WHO desirable limits. The results also indicated that the well water
from Benin City contained concentrations of chromium, 0.18 mg/L; and lead, 0.20 mg/L that exceeded the recommended WHO limits.
In Ekpoma, the pH, 6.00; concentrations of chromium, 0.15 mg/L; and lead, 0.44 mg/L were higher than the desirable limits
of WHO. Generally, the assessments revealed that the waters were good and fit for drinking and other domestic application
without serious threat to public health. 相似文献
10.
J. J. M. Cuppen G. F. Wiegertjes H. W. J. Lobee H. F. J. Savelkoul M. A. Elmusharaf A. C. Beynen H. N. A. Grooten W. Smink 《The Environmentalist》2007,27(4):577-583
A hypothesis is proposed how Low Frequency Electromagnetic Field (LF EMF) exposure can stimulate an immune response, based
on recent insights in immunology. We hypothesize that the Immunent EMF treatment induces mild stress to cells, which then
produce cytokines that function as alarms or so called danger signals for the immune system. In this way EMF treatment takes
the place of multiplying pathogens, and the damage these cause, in the triggering of an immune response. In a first series
of experiments in␣vitro common carp head kidney-derived phagocytes were used to determine ROS production as a measure for
immune activation. Exposure to LF EMF signals (200–5,000 Hz) at 5 μT or 1.5 mT led to 42 or 33% increase in immune activity,
respectively, compared to negative control values. EMF could also additionally stimulate chemically pre-stimulated samples
up to 18% (5 μT) or 22% (1.5 mT). Significance of increase in ROS production in the total series was: p < 0.0001. In a second series of experiments in␣vitro commercial goldfish were used. Groups of fish were housed under equal
conditions in at least four control tanks and 8–16 EMF-exposed tanks. Exposure was done with a predominantly vertical field
at field strengths (rms) between 0.15 and 50 μT. Without treatment mortality was about 50% after 18 days, while the treatment
at 5 μT reduced it to 20% on average. At field strengths 0.15, 0.5, 1.5, 5, 15 and 50 μT an equally strong effect was found.
Reducing the field strength to 0.05, 0.06, 0.01 and 0.003 μT showed a gradually decreasing effect, which only at 0.003 μT
is no longer statistically significant. Finally, in␣vitro experiments were done with 560 commercial broiler chickens exposed
to infection pressure from coccidiosis. EMF exposure at 6.5 μT reduced intestinal lesions by 40% and improved feed conversion
by 8%. 相似文献
11.
Eleni Nanou Vassilis Tsiafakis E. Kapareliotis Charalabos Papageorgiou Andreas Rabavilas Christos Capsalis 《The Environmentalist》2005,25(2-4):173-179
Summary The effects of electromagnetic fields (EMF) emitted by cellular phones on human electroencephalogram (EEG) were studied during
an auditory memory task. The experimental method and the experimental setup are introduced as a credible measurement method
of EEG. 19 normal subjects (10 women and 9 men) performed the memory task both with and without exposure to a 900 MHz signal,
emitted by a dipole antenna placed near the subjects' head. The energy of the EEG signals was calculated at the time domain.
A Fourier transform of the EEG signals was done and the EEG energy was also calculated at the frequency domain. As the Parseval's
theorem anticipates the energies were identical. The EEG energy was found concentrated at the four basic bands (α (8–13 Hz),
β(14–30 Hz), δ (0–4 Hz) and θ(5–7 Hz)). The primary concern of the present study was the gender related influence of EMF on
the spectral energy of EEG. The results show evidence of a strong gender—radiation interaction effect on the EEG energy and
on the peak amplitudes within each of the four rhythms. Without radiation the spectral power of males is greater than of females,
while under exposure the situation is reversed. Under the influence of EMF the spectral power of the males EEG is decreased
while that of the females is increased. In conclusion both the baseline EEG and the changes effected to the EEG power spectrum
under the influence of EMF seem to be gender dependent. 相似文献
12.
The present study investigated the influence of electromagnetic fields (EMF), similar to that emitted by mobile phones, on
brain activity. Ten women and ten men, matched for age and educational level, performed a short memory task (Wechsler test),
with simultaneous Electroencephalogram (EEG) recordings at 15 scalp electrodes, both without (baseline) and with exposure
to an 1,800 MHz signal. The EEG energy was found concentrated at the four basic EEG bands [α (8–13 Hz), β (14–30 Hz), δ (0–4 Hz), and θ (5–7 Hz)]. The analysis revealed that in the presence of EMF, the energy of the β band was significantly greater for females than for males at the majority of the electrodes. Since beta oscillation is associated
with the shift of attention during the perception, these findings may indicate that the particular EMF (1,800 MHz signal)
exerts an influence on this brain activity, which appears to be gender-related. 相似文献
13.
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
14.
Cindy Sage 《The Environmentalist》2012,32(2):144-156
The meltdown and release of radioactivity (ionizing radiation) from four damaged nuclear reactors at the Fukushima Nuclear
Facility in Japan in March 2011 continues to contaminate air and ocean water even 1 year later. Chronic exposure to low-dose
ionizing radiation will occur over large populations well into the future. This has caused grave concern among researchers
and the public over the very long period of time expected for decommissioning alone (current estimate from official sources
is 30–40 years based on TEPCO in Mid-and long-term roadmap towards the decommissioning of Fukushima Daiichi nuclear power
units 1–4, 2011) and the presumed adverse effects of chronic, low-dose ionizing radiation on children, adults and the environment. Ultimately,
radioactive materials from Fukushima will circulate for many years, making health impacts a predictable concern for many generations
(Yasunari et al. in PNAS 108(49):19530–19534, 2011). There is long-standing scientific evidence to suggest that low-dose ionizing radiation (LD-IR) and low-intensity non-ionizing
electromagnetic radiation (LI-NIER) in the form of extremely low-frequency electromagnetic fields and radiofrequency radiation
(RFR) share similar biological effects. Public health implications are significant for reconstruction efforts to rebuild in
post-Fukushima Japan. It is relevant to identify and reduce exposure pathways for chronic, low-dose ionizing radiation in
post-Fukushima Japan given current scientific knowledge. Intentional planning, rather than conventional planning, is needed
to reduce concomitant chronic low-intensity exposure to non-ionizing radiation. These are reasonably well-established risks
to health in the scientific literature, as evidenced by their classification by World Health Organization International Agency
for Research on Cancer as Possible Human Carcinogens. Reducing preventable, adverse health exposures in the newly rebuilt
environment to both LD-IR and LI-NIER is an achievable goal for Japan. Recovery and reconstruction efforts in Japan to restore
the communications and energy infrastructure, in particular, should pursue strategies for reduction and/or prevention of both
kinds of exposures. The design life of buildings replaced today is probably 35–50 years into the future. Cumulative health
risks may be somewhat mitigated if the double exposure (to both chronic low-dose IR from the Fukushima reactors and LI-NIER
[EMF and RFR] in new buildings and infrastructure) can be dealt with effectively in early planning and design in Japan’s reconstruction. 相似文献
15.
Omotayo Rafiu Awofolu 《The Environmentalist》2006,26(4):285-293
Groundwater (well water) from a residential area within the vicinity of an industrial estate in Lagos, Nigeria were sampled
and analysed by Flame Atomic Absorption Spectroscopy for their heavy metals content. This was with a view of assessing the
quality of the water, which was being used for domestic activities, especially, drinking usually without treatment. Total
trace metal determination by mineral acid digestion of water samples was applied. This method proved to be better than an
extractive concentration technique in the quality assurance protocols with the recovery range being 90.7 ± 0.006–97.6 ± 0.003%.
Mean concentration of trace metals in water samples ranged from Fe: 0.05–0.47 mg l−1; Al: 0.1–1.54 mg l−1; Cu: 0.14–1.39 mg l−1; Zn: 0.04–0.43 mg l−1; Cd: trace–0.02 mg l−1; Pb: trace–0.03 mg l−1, Mn: 0.01–0.18 mg l−1 and Ni: 0.02–0.11 mg l−1. Physical parameters of water samples examined were within the drinking water safety limits except for conductivity. Results
generally indicate the presence of heavy metal constituents in groundwater samples. Detection of metals such as cadmium and
lead which have serious health implications above WHO and USEPA limits in drinking water gives cause for concern. 相似文献
16.
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
17.
Pawel Bienkowski 《The Environmentalist》2009,29(2):130-134
This article presents methods and results of interlaboratory comparison in the electromagnetic field (EMF) survey measurements
performed by Electromagnetic Environment Protection Laboratory. Based on the results, the author analyzed factors affecting
the precision of EMF measurements, in particular—difficult to estimate—the “human factor”. In practice, the human factor has
never been taken into account in the EMF measurements accuracy estimations budget, and the author estimate the importance
of this factor that may include even up to half of the total uncertainty of measurements. Taking into account all factors
depredating the accuracy of measurements, the uncertainty of the survey EMF measurements was estimated at the level of 2–4 dB. 相似文献
18.
Summary Biological effects of extremely low-frequency electromagnetic fields (ELF-EMF) on microcirculation were investigated in vivo by monitoring arteriole diameters in conscious mice. Measurements of blood vessel diameter were monitored 33 min non-stop
before during and after exposure with ELF-EMF and every 389 ms blood vessel diameter were calculated.
Using a dorsal skinfold chamber (DSC), and following caudal vein injection of FITC-dextran 250 kDa, the microvasculature (initial
arteriole diameter of 45–80 μm), was examined by intravital microscopy and video images were recorded for a total time of
33 min. Arteriole diameter was continuously measured by on-line analysis using a High-speed Digital Machine Vision System
CV-2100, using an edge-gap detection algorithm. Since vessel diameters exhibit rhythmic variation expressed by vasomotion,
for estimation of microcirculatory activity we used both raw data for frequency analysis of vasomotion (measured frequencies
of vasomotion were in the range 0.008÷0.1 Hz) and evaluate mean blood vessel diameter for each 1 min period of time, and make
a comparison between Pre, Exposure/Sham exposure and Post exposure periods, with the aim to evaluate possible changes in mean
blood vessel diameter as a result of ELF-EMF action.
During EMF exposure and post-exposure periods, arteriole diameters increased significantly compared with the pre-exposure
period, and the changes were larger during post-exposure. In contrast to sham exposure, vasodilatation of the microvasculature
was significantly greater during exposure and post-exposure to 16 Hz EMF. These findings suggest that ELF-EMF may have potential
therapeutic use benefit for treating vascular disorders. 相似文献
19.
Andreas Neocleous 《The Environmentalist》2005,25(2-4):247-250
Summary This paper deals with the evaluation of Extremely Low Frequency (ELF) Electromagnetic Fields (EMF) produced by high tension
wires on pylons and substations, which were preliminarily investigated by taking measurements in schools (on behalf of the
Environmental Committee of Limassol). It publicizes the level of EMF from the above sources and makes an attempt to compare
them with various exposure limits.
Finally, certain measures to be taken by the responsible authorities are suggested, as possible actions aiming at the protection
of the Cypriot people from any EMF health risk. 相似文献
20.
Changes of Surface Properties of Yeast Cell Wall Under Exposure of Electromagnetic Field (40.68 MHz) and Action of Nystatin 总被引:1,自引:0,他引:1
S. I. Voychuk E. N. Gromozova P. M. Lytvyn V. S. Podgorsky 《The Environmentalist》2005,25(2-4):139-144
Summary Changes of the surface properties were studied in the cell wall of the yeast Saccharomyces cerevisiae Y-517 under influence of the electromagnetic field (EMF) (40.68 MHz) and lethal doses of the fungicidal antibiotic nystatin
(10 μg/106 cells). Atomic force microscopy was used to study surface topography and visco-elastic properties of the cell walls. Surface
carbohydrates were detected by lectins marked with gold with the help of the scanning electron microscope. Additional polysaccharide
layer appeared over cell surface after EMF exposure. We suggest that electromagnetic fields resulted in the change of the
cell surface, and, accordingly, the sensitivity of organisms to the antifungal antibiotics. 相似文献