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1.
Front Zool ; 21(1): 14, 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38807222

RESUMEN

The investigation of the effects of artificial 50 Hz electric field (E-field) frequency on Apis mellifera is a relatively new field of research. Since the current literature focuses mainly on short-term effects, it is unknown whether E-fields have permanent effects on bees or whether their effects can be neutralized. In this study we assessed gene expression immediately after exposure to the E-field, as well as 7 days after exposure. The aim of this work was to identify potentially dysregulated gene transcripts in honey bees that correlate with exposure time and duration to E-fields.Newly emerged bees were marked daily with a permanent marker (one color for each group). Then bees were exposed to the 50 Hz E-field with an intensity of 5.0 kV/m or 10.0 kV/m for 1-3 h. After exposure, half of the bees were analyzed for gene expression changes. The other half were transferred to a colony kept in a mini-hive. After 7 days, marked bees were collected from the mini-hive for further analysis. Six regulated transcripts were selected of transcripts involved in oxidative phosphorylation (COX5a) and transcripts involved in endocrine functions (HBG-3, ILP-1), mitochondrial inner membrane transport (TIM10), and aging (mRPL18, mRPS30).Our study showed that in Apis mellifera the expression of selected genes is altered in different ways after exposure to 50 Hz electric fields -. Most of those expression changes in Cox5a, mRPL18, mRPS30, and HGB3, were measurable 7 days after a 1-3 h exposure. These results indicate that some E-field effects may be long-term effects on honey bees due to E-field exposure, and they can be observed 7 days after exposure.

2.
PLoS One ; 18(5): e0285522, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37172069

RESUMEN

There are many artificial sources of radiofrequency electromagnetic field (RF-EMF) in the environment, with a value between 100 MHz and 6 GHz. The most frequently used signal is with a frequency of around 900 MHz. The direction of these changes positively impacts the quality of life, enabling easy communication from almost anywhere in the world. All living organisms in the world feel the effects of the electromagnetic field on them. The observations regarding the influence of a RF-EMF on honey bees, describing the general impact of RF-EMF on the colony and/or behavior of individual bees, such as reduction in the number of individuals in colonies, extended homing flight duration, decrease in breeding efficiency, changes in flight direction (movement of bees toward the areas affected by RF-EMF), increase in the intensity and frequency of sounds characteristic for those announcing the impending danger. In this work, we describe the changes in the levels of some of the stress-related markers in honey bees exposed to varying intensities and duration of RF-EMF. One-day-old honeybee worker bees were used for the study. The bees were randomly assigned to 9 experimental groups which were exposed to the following 900 MHz EMF intensities: 12 V/m, 28 V/m, and 61 V/m for 15 min, 1 h and 3 h. The control group was not exposed to the RF-EMF. Each experimental group consisted of 10 cages in which were 100 bees. Then, hemolymph was collected from the bees, in which the activity was assessed AST, ALT, ALP, GGTP, and level of nonenzymatic antioxidants albumin, creatinine, uric acid, and urea. Bees were also collected for the analysis of rps5, ppo, hsp10, hsp70, hsp90, and vitellogenin gene expression. Our study shows that exposure to a 900 MHz electromagnetic field induces a response in the honey bees that can be detected in the level of enzyme activity and the expression of stress-related genes. The response is similar to the one previously described as a result of exposition to UVB irradiation and most likely cannot be attributed to increased temperature.


Asunto(s)
Campos Electromagnéticos , Calidad de Vida , Abejas/genética , Animales , Campos Electromagnéticos/efectos adversos , Antioxidantes , Ondas de Radio/efectos adversos , Ácido Úrico
3.
Animals (Basel) ; 12(7)2022 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-35405844

RESUMEN

Earth's magnetic field (MF) plays an important role for many species, including the honeybee, in navigation. Nowadays, much larger alternating fields are emitted by miscellaneous electric infrastructure components, such as transformers and power lines, and the environment is therefore polluted by an anthropogenic electromagnetic field, though little is known regarding its impact on living organisms. The behavior of animals is the first and easiest way to establish the impact of stress. It shows if the animal can detect the exposure and react to it. To investigate this, one-day-old bees were exposed to a 50 Hz magnetic field of induction at 1 mT and 1.7 mT for 10 min, 1 h, and 3 h under laboratory conditions. All groups exposed to the magnetic field showed differences in behavioral patterns. What is more, they presented a behavior absent in the control: loss of balance. There were differences, both in the ratio of behaviors and in the number of bouts-exposed bees more often changed behavior. Occurrence of differences is an indication of the reaction of the honeybee organism to the magnetic field. Loss of balance is a disturbing symptom, and behavior changes indicate a disturbance of the honeybee by the electromagnetic field.

4.
Sensors (Basel) ; 21(12)2021 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-34204546

RESUMEN

Microwave imaging and defectoscopy are promising techniques for dielectric composite evaluation. Their most significant advantage is their relatively high penetration depth. Another feature worth noting is that traditional methods could not acquire an internal content with such a low impact on both the sample and surrounding environment, including the test operator, compared to other techniques. This paper presents microwave non-destructive and noninvasive methods for quality evaluation of layered composite materials using an open-ended waveguide probe. Pure |S11| parameters only exceptionally give a clear answer about the location of material cracks. Therefore, this makes it necessary to analyze these parameters simultaneously along with several other factors, such as stand-off distance, probe type or wave polarization. The purpose of the work was to find the dependency between the physical state of a layered composite powerplant pipeline and the S-matrix parameters response (reflection and transmission parameters) in a Ku frequency band that has not yet been extensively researched. Lower-frequency measurements broaden the application possibility for thicker composites, mainly because of a higher penetration depth and measurement setup availability. Different methods have been shown, including reflection and transmission/reflection methods, both in close proximity and in stand-off distance. The measurements are based on a low-complexity experimental setup.

5.
PLoS One ; 16(6): e0252858, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34166412

RESUMEN

The amount of artificial electromagnetic fields of various parameters in the honey bee's environment increases globally. So far, it had been proven that exposure to an E-field at 50 Hz can cause changes in bee's behavior, alter the activity of proteases, and enzymatic antioxidants. Due to the potentially harmful effect of this factor on honey bees, we decided to investigate the activity of aspartate aminotransferase (AST), alanine aminotransferase (ALT), and alkaline phosphatase (ALP), and the concentration of albumin and creatinine in bee's hemolymph after exposure to 50 Hz E-field. Honey bee workers were placed in wooden cages (200 × 150 × 70 mm) and exposed to the 50 Hz E-field with the intensity of <1, 5.0, 11.5, 23.0, or 34.5 kV/m for 1, 3, 6, or 12h. A homogeneous 50 Hz E-field was generated in the form of a plate capacitor. Hemolymph samples for analysis were taken immediately after the end of exposure to the E-field from 100 bees from each group. According to our study, the activity of AST, ALT, and ALP in honey bees' hemolymph decreased after exposure to 50 Hz E-field with various intensities. The decrease in AST, ALT, and ALP activity intensified with prolonged exposure time. 50 Hz E-field may cause the impairment of crucial metabolic cycles in the honey bees' organism (such as the citric acid cycle, ATP synthesis, oxidative phosphorylation, ß-oxidation). Moreover, exposure to E-Field altered the concentration of creatinine and albumin, which are important non-enzymatic antioxidants. Such changes may indicate a disturbance in protein metabolism and increased muscle activity.


Asunto(s)
Abejas/metabolismo , Biomarcadores/metabolismo , Electricidad/efectos adversos , Hemolinfa/metabolismo , Proteínas de Insectos/metabolismo , Animales , Abejas/efectos de los fármacos , Hemolinfa/efectos de los fármacos
6.
Animals (Basel) ; 11(3)2021 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-33803600

RESUMEN

The effect of an artificial electromagnetic field on organisms is a subject of extensive public debate and growing numbers of studies. Our study aimed to show the effect of an electromagnetic field at 50 Hz and variable intensities on honey bee proteolytic systems and behavior parameters after 12 h of exposure. Newly emerged worker bees were put into cages and exposed to a 50 Hz E-field with an intensity of 5.0 kV/m, 11.5 kV/m, 23.0 kV/m, or 34.5 kV/m. After 12 h of exposure, hemolymph samples were taken for protease analysis, and the bees were recorded for behavioral analysis. Six behaviors were chosen for observation: walking, flying, self-grooming, contact between individuals, stillness, and wing movement. Bees in the control group demonstrated the highest number of all behavior occurrences, except flying, and had the lowest protease activity. Bees in the experimental groups showed a lower number of occurrences of walking, self-grooming, and contacts between individuals than the control bees and had significantly higher protease activity than the control bees (except that of alkaline proteases in the 23.0 kV/m group).

7.
Animals (Basel) ; 11(2)2021 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-33498413

RESUMEN

EM-fields come from both natural and anthropogenic sources. This study aimed to investigate changes in honeybee behavior parameters under the influence of an electric field at 50 Hz and variable intensity. Bees were exposed for 1 h, 3 h, or 6 h to the following artificial E-field intensities: 5.0 kV/m, 11.5 kV/m, 23.0 kV/m, or 34.5 kV/m. Bees in the control group were under the influence of an E-field <2.0 kV/m. Six basic behaviors were selected for bee observation (walking, grooming, flight, stillness, contact between individuals, and wing movement). Our research shows the impact of bee exposure time on behavioral change within groups. Exposure for 3 h caused a decrease in the time that bees spent on behaviors and in the number of occurrences. After 6 h, the parameters increased within the groups, as was the case with 1 h exposure. This may indicate that there is a behavioral barrier that allows the pattern to normalize for some time.

8.
Insects ; 11(10)2020 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-33081029

RESUMEN

In recent years, on a global scale, more and more reports of a phenomenon called CCD (Colony Collapse Disorder) have been reported. In addition to pesticides, diseases, and other environmental stressors, electromagnetic fields are also mentioned as one of the possible causes of CCD. One of the body's first lines of defense against harmful factors is the antioxidant system. We hypothesized that electromagnetic field upregulate the activity of SOD (superoxide dismutase), CAT (catalases), and changed FRAP (total antioxidant potential) in honeybee hemolymph. In our research, 12 h bee's exposure to E-field was analyzed to determine changes in the antioxidant system. The frequency of 50 Hz and various intensities were used: 5.0 kV/m, 11.5 kV/m, 23.0 kV/m, and 34.5 kV/m. Superoxide dismutase was characterized by four times higher activity in the study groups as compared to the control group. Catalase activity in all groups was characterized by statistically significantly different activity between the groups. The highest activity was recorded in the 34.5 kV/m group. The lowest activity was recorded in the 11.5 kV/m group. A relationship was found between different E-field intensities and changes in the antioxidant system.

9.
Med Pr ; 71(2): 245-253, 2020 Mar 30.
Artículo en Polaco | MEDLINE | ID: mdl-31793558

RESUMEN

In 2017, preparations were made in Poland to provide all citizens with access to the Internet at a speed of at least 30 Mb/s, and at a speed of at least 100 Mb/s for 50% of households. This goal is to be realized, among others, by means of the fifth generation (5G) radio-communication networks. This work presents the assumptions of the 5G network structure and estimates of the level of population exposure toelectromagnetic fields related to their rational use. It was also analyzed whether, from the technical point of view, 5G networks could be implemented while respecting the currently acceptable level of electromagnetic field intensity in Poland (7 V/m), taking into account the current environmental exposure caused by antennas of cellular base stations. This is a contribution to the ongoing discussion on the need to change the requirements in Poland in order to limit the level of population exposure to electromagnetic fields. Based on the available documentation of the proposed technical standards, the theoretical analysis of environmental exposure to the electromagnetic field emitted by 5G systems shows that, with rational power management, obtaining the expected (compatible with 5G standards) quality of connections via base stations installed outside of buildings and using intelligent antenna systems with controlled beams, it will be possible to maintain the electric field strength and power density below the current limit values in places accessible to the public (<7 V/m, <0.1 W/m2). Med Pr. 2020;71(2):245-53.


Asunto(s)
Teléfono Celular , Campos Electromagnéticos , Exposición a Riesgos Ambientales , Humanos , Polonia , Salud Pública
10.
Med Pr ; 71(1): 105-113, 2020 Jan 20.
Artículo en Polaco | MEDLINE | ID: mdl-31793559

RESUMEN

There is an ongoing discussion about electromagnetic hazards in the context of the new wireless communication technology - the fifth generation (5G) standard. Concerns about safety and health hazards resulting from the influence of the electromagnetic field (EMF) emitted by the designed 5G antennas have been raised. In Poland, the level of the population's exposure to EMF is limited to 7 V/m for frequencies above 300 MHz. This limitation results from taking into account the protective measures related not only to direct thermal hazards, but also to diversified indirect and long-term threats. Many countries have not established legal requirements in this frequency range, or they have introduced regulations based on recommendations regarding protection against direct thermal risks only (Council Recommendation 1999/519/EC). For such protection, the permissible levels of electric field intensity are 20-60 V/m (depending on the frequency). This work has been created through an interdisciplinary collaboration of engineers, biologists and doctors, who have been for many years professionally dealing with the protection of the biosphere against the negative effects of EMF. It presents the state of knowledge on the biological and health effects of the EMF emitted by mobile phone devices (including millimeter waves which are planned to be used in the 5G network). A comparison of the EU recommendations and the provisions on public protection being in force in Poland was made against this background. The results of research conducted to date on the biological effects of the EMF radiofrequency emitted by mobile telecommunication devices, operating with the frequencies up to 6 GHz, do not allow drawing any firm conclusions; however, the research evidence is strong enough for the World Health Organization to classify EMF as an environmental factor potentially carcinogenic to humans. At the moment, there is a shortage of adequate scientific data to assess the health effects of exposure to electromagnetic millimeter waves, which are planned to be used in the designed 5G devices. Nevertheless, due to the fact that there are data indicating the existence of biophysical mechanisms of the EMF influence that may lead to adverse health effects, it seems necessary to use the precautionary principle and the ALARA principle when creating environmental requirements for the construction and exploitation of the infrastructure of the planned 5G system. Med Pr. 2020;71(1):105-13.


Asunto(s)
Campos Electromagnéticos , Exposición a Riesgos Ambientales , Salud Poblacional , Ondas de Radio , Teléfono Celular , Humanos , Polonia
11.
Med Pr ; 70(5): 567-585, 2019 Sep 18.
Artículo en Polaco | MEDLINE | ID: mdl-31475993

RESUMEN

BACKGROUND: The paper describes the current legal status related to electromagnetic field (EMF) measurements in the context of environmental protection. It also presents the assumptions and exemplary results obtained from the EMF National Monitoring System which, in the authors' opinion, could be more reliable and better adapted to the current state of affairs in the radiocommunication industry. MATERIAL AND METHODS: A simplified method of estimating electromagnetic field intensity from various sources, including in particular cellular base stations, using their basic parameters, was described. The electromagnetic field monitoring system operating in Poland was described, and alternative monitoring methods were presented. The authors introduced their own concept of mobile monitoring, whose assumptions perfectly fit into the current realities and can be performed with the use of the current measurement equipment available to laboratories of the Voivodeship Inspectorates for Environmental Protection. RESULTS: The construction of the measurement system was presented, and its measurement verification was carried out. Measurement errors resulting from the use of weather-resistant casing and from placing the device on the roof of the vehicle were estimated, confirming that their impact on the measurement uncertainty budget tends to be negligible. Auxiliary software for mobile monitoring was presented, with the aid of which verification was made by carrying out monitoring measurements in the city of Wroclaw. CONCLUSIONS: The results obtained during the monitoring measurements in real conditions confirmed that the proposed method provides reliable results, which are not burdened with significant errors and distortions resulting from the proposed measurement methodology or from the construction of the measurement system itself. The developed system does not require significant financial outlays and is a perfect complement to the stationary measurements currently performed within the Environmental Monitoring System. Med Pr. 2019;70(5):567-85.


Asunto(s)
Campos Electromagnéticos , Exposición a Riesgos Ambientales , Monitoreo de Radiación , Humanos , Polonia
12.
Int J Phytoremediation ; 21(3): 246-250, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30656975

RESUMEN

It is known that both natural and artificial electric fields (EF) affect plants physiological parameters as well as germination, growth and yield. The present article describes results of a preliminary experiment on the impact of electric field on aquatic plants biogeochemistry. The objective of the present study was the assessment of the influence exerted by the electric field on growth and trace metals content of Elodea canadensis. In a laboratory experiment plants were exposed to the field intensity of 54 kV m-1 for 7 days. The plants length was measured and the content of Fe, Mn, Ni, Pb, and Zn was determined using atomic absorption spectrometry (AAS). Results showed that the application of electric field slightly enhanced the growth of E. canadensis shoots. The content of Mn and Ni was significantly lower, and Pb and Zn significantly higher in plants exposed to the electric filed, while Fe content did not differ between control and EF treatment. This provides a rationale for further studies on biological effects of electric field in trace metal contaminated waters and application of an electrically enhanced phytoremediation.


Asunto(s)
Hydrocharitaceae , Metales Pesados/análisis , Oligoelementos/análisis , Biodegradación Ambiental , Metales/análisis
13.
Med Pr ; 68(6): 693-703, 2017 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-28930303

RESUMEN

BACKGROUND: Presented information about the welding process and equipment, focusing on the emission of electromagnetic field (EMF) with levels significant in terms of the labor safety regulations in force in Poland - the ordinances of the Minister of Family, Labour and Social Policy that came into force on June 27, 2016 and June 29, 2016 - emerged due to harmonization with European Union directive 2013/35/EU of 26 June 2013 of the European Parliament and the Council. They presented methods of determination of the EMF distribution in the welding machine surroundings and analyzed the background knowledge from the available literature. MATERIAL AND METHODS: The subject of the analysis included popular high frequency welders widely used in the industry. Electromagnetic field measurements were performed in the welder operating place (in situ) during machine normal operations, using measurement methods accordant with labor safety regulations in force in Poland and according to the same guidelines, the EMF distributions and parameters having been described. RESULTS: They presented various scenarios of particular, real examples of excessive exposure to EMF in the dielectric welder surroundings and showed solutions, ranging from simple and costless and ending on dedicated electromagnetic shielding systems, which allowed to reduce EMF exposure in some cases of more than 80% (protection zone ranges) or eliminate dangerous zone presence. CONCLUSIONS: It has shown that in the dielectric welders surrounding, significant EMF strength levels may be the result of errors or omissions which often occur during development, installation, operation or modification of welding machines. It has allowed to present the measures that may significantly reduce the exposure to EMF of workers in the welder surroundings. The role of accredited laboratories in helping in such cases was underlined. Med Pr 2017;68(6):693-703.


Asunto(s)
Campos Electromagnéticos , Exposición Profesional/análisis , Monitoreo de Radiación/normas , Soldadura/normas , Unión Europea , Mano/efectos de la radiación , Cabeza/efectos de la radiación , Humanos , Concentración Máxima Admisible , Polonia , Valores Limites del Umbral , Torso/efectos de la radiación
14.
Med Pr ; 66(5): 701-12, 2015.
Artículo en Polaco | MEDLINE | ID: mdl-26647988

RESUMEN

BACKGROUND: This paper presents the characteristics of the mobile phone base station (BS) as an electromagnetic field (EMF) source. The most common system configurations with their construction are described. The parameters of radiated EMF in the context of the access to methods and other parameters of the radio transmission are discussed. Attention was also paid to antennas that are used in this technology. MATERIAL AND METHODS: The influence of individual components of a multi-frequency EMF, most commonly found in the BS surroundings, on the resultant EMF strength value indicated by popular broadband EMF meters was analyzed. The examples of metrological characteristics of the most common EMF probes and 2 measurement scenarios of the multisystem base station, with and without microwave relays, are shown. RESULTS: The presented method for measuring the multi-frequency EMF using 2 broadband probes allows for the significant minimization of measurement uncertainty. Equations and formulas that can be used to calculate the actual EMF intensity from multi-frequency sources are shown. They have been verified in the laboratory conditions on a specific standard setup as well as in real conditions in a survey of the existing base station with microwave relays. CONCLUSIONS: Presented measurement methodology of multi-frequency EMF from BS with microwave relays, validated both in laboratory and real conditions. It has been proven that the described measurement methodology is the optimal approach to the evaluation of EMF exposure in BS surrounding. Alternative approaches with much greater uncertainty (precaution method) or more complex measuring procedure (sources exclusion method) are also presented).


Asunto(s)
Teléfono Celular , Campos Electromagnéticos , Exposición a Riesgos Ambientales/análisis , Monitoreo de Radiación/instrumentación , Ondas de Radio , Polonia
15.
Electromagn Biol Med ; 34(3): 257-61, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26444202

RESUMEN

The article describes the character of electromagnetic field (EMF) in mobile phone base station (BS) surroundings and its variability in time with an emphasis on the measurement difficulties related to its pulse and multi-frequency nature. Work also presents long-term monitoring measurements performed recently in different locations in Poland - small city with dispersed building development and in major polish city - dense urban area. Authors tried to determine the trends in changing of EMF spectrum analyzing daily changes of measured EMF levels in those locations. Research was performed using selective electromagnetic meters and also EMF meter with spectrum analysis.


Asunto(s)
Teléfono Celular/instrumentación , Campos Electromagnéticos , Exposición a la Radiación/análisis , Factores de Tiempo
16.
Med Pr ; 66(2): 185-97, 2015.
Artículo en Polaco | MEDLINE | ID: mdl-26294311

RESUMEN

BACKGROUND: Experiments on the electromagnetic field influence on organisms are an important part of biophysical studies. It is an interdisciplinary research spanning biology and medicine with the engineering in generation and measurement of electromagnetic fields. The aim of the study consists the analysis of parameters estimations and measurements of extremely low frequency magnetic field (ELF MF) as well as exposure systems parameters in biomedical research. MATERIAL AND METHODS: Experiments were performed on 2 most popular low magnetic field exposure systems: the solenoid and Helmholtz coils. A theoretical analysis and a measurement verification of the magnetic field distribution inside the systems were carried out to evaluate the homogeneity of the magnetic field. Additional factors, vibrations and temperature changes, affecting the assessment of the biological effects of magnetic field exposure were also examined. RESULTS: Based on the study results, a comparative analysis of solenoids and Helmholtz coils as the magnetic field exposure systems was presented. Proposals for the description of magnetic field exposure were also formulated. CONCLUSIONS: The authors emphasize the importance of a conscious choice of exposure conditions and their explicit description. These are fundamental requirements for both the reproduction of experiniental conditions and the verification of results.


Asunto(s)
Campos Electromagnéticos/efectos adversos , Exposición Profesional/análisis , Salud Laboral , Lugar de Trabajo , Electricidad/efectos adversos , Humanos , Enfermedades Profesionales/diagnóstico , Exposición Profesional/prevención & control , Medición de Riesgo
17.
Med Pr ; 62(1): 37-45, 2011.
Artículo en Polaco | MEDLINE | ID: mdl-21748882

RESUMEN

BACKGROUND: The paper presents changes in the electromagnetic field intensity in a school building and its surrounding after the mobile phone base station installation on the roof of the school. MATERIAL AND METHODS: The comparison of EMF intensity measured before the base station was launched (electromagnetic background measurement) and after starting its operation (two independent control measurements) is discussed. RESULTS: Analyses of measurements are presented and the authors also propose the method of the electromagnetic field distribution adjustment in the area of radiation antennas side lobe to reduce the intensity of the EMF level in the base station proximity. The presented method involves the regulation of the inclination. CONCLUSIONS: On the basis of the measurements, it was found that the EMF intensity increased in the building and its surroundings, but the values measured with wide margins meet the requirements of the Polish law on environmental protection.


Asunto(s)
Teléfono Celular , Campos Electromagnéticos , Exposición a Riesgos Ambientales/análisis , Monitoreo de Radiación/métodos , Medición de Riesgo/métodos , Relación Dosis-Respuesta en la Radiación , Humanos , Polonia , Traumatismos por Radiación/prevención & control , Liberación de Radiactividad Peligrosa/prevención & control , Factores de Riesgo , Instituciones Académicas
18.
Med Pr ; 61(2): 233-9, 2010.
Artículo en Polaco | MEDLINE | ID: mdl-20509560

RESUMEN

The work addresses technical aspects of the assessment of exposure to electromagnetic fields (EMF) in the environment based on cellular telephony systems. In this paper, EMF parameters, important to the biosphere exposure, are discussed, and the methods for the EMF assessment: theoretical analysis of EMF intensity in the proximity of EMF sources and also the measurements in situ, are described. The review of measurement methods, identification of limitations of measuring devices, estimation of the expected EMF intensity in the municipal environment and environmental measurements uncertainty are presented. M


Asunto(s)
Teléfono Celular , Campos Electromagnéticos , Exposición a Riesgos Ambientales/análisis , Monitoreo de Radiación/métodos , Humanos , Exposición Profesional/análisis , Polonia , Control de Calidad , Dosis de Radiación , Protección Radiológica/métodos , Ondas de Radio
19.
Med Pr ; 59(6): 513-9, 2008.
Artículo en Polaco | MEDLINE | ID: mdl-19388464

RESUMEN

In the paper a review of electromagnetic field sources in radio- and microwave- frequency range is presented. The aim of the study was to analyze possibilities and methods used to survey electromagnetic field (EMF) measurements. Selective and broadband methods with examples of apparatus are described. The accuracy of typical EMF survey measurements was estimated.


Asunto(s)
Conservación de los Recursos Naturales/métodos , Campos Electromagnéticos , Monitoreo de Radiación/métodos , Protección Radiológica/métodos , Administración de la Seguridad/métodos , Exposición a Riesgos Ambientales/análisis , Microondas , Exposición Profesional/análisis , Polonia , Monitoreo de Radiación/instrumentación , Ondas de Radio
20.
Med Pr ; 58(2): 117-23, 2007.
Artículo en Polaco | MEDLINE | ID: mdl-17926500

RESUMEN

BACKGROUND: The aim of the study was to analyze and modify methods used to estimate the range of restricted area corresponding with the limitation of exposure of the general public to electromagnetic fields in the vicinity of microwave relay antenna systems. MATERIALS AND METHODS: In this paper a well known spherical-wave model is revised. Some drawbacks of this model in terms of the microwave relay antenna systems are shown and a method for their elimination is proposed. The idea of this method is based on placing an equivalent point source of radiation behind the actual antenna, and then on taking into account the power density produced by this source over the antenna aperture. RESULTS: In the course of the study an algorithm for the range of restricted area estimation was developed. Some results of calculation validating the proposed method are presented. CONCLUSIONS: The proposed model and algorithm for the range of restricted area estimation may be employed in administrative procedures for evaluating the effects exerted on the environment. The proposed method can be regarded as an alternative to the presently employed spherical wave approach in the case of the microwave relay antenna systems.


Asunto(s)
Campos Electromagnéticos , Exposición a Riesgos Ambientales , Microondas , Algoritmos , Humanos , Modelos Biológicos , Dosis de Radiación , Monitoreo de Radiación , Radiometría
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