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EN
Introduction: The paper reports the results of the determinations of UMTS EMF distributions in the driver's cab of motor vehicle simulators. The results will serve as the basis for future research on the influence of EMF emitted by mobile phones on driver physiology. Materials and Methods: Two motor vehicle driving simulators were monitored, while an EMF source was placed at the driver's head or on the dashboard of the motor vehicle driving simulator. For every applied configuration, the maximal electric field strength was measured, as were the values at 16 points corresponding to chosen locations on a driver's or passenger's body. Results: When the power was set for the maximum (49 mW), a value of 27 V/m was measured in the vicinity of the driver's head when the phone was close to the head. With the same power, when the phone was placed on the dashboard, the measured maximum was 15.2 V/m in the vicinity of the driver's foot. Similar results were obtained for the passenger. Significant perturbations in EMF distribution and an increase in electric field strength values in the motor vehicle driving simulator were also observed in comparison to free space measurements, and the electric field strength was up to 3 times higher inside the simulator. Conclusions: This study can act as the basis of future studies concerning the influence of the EMF emitted by mobile phones on the physiology of the driver. Additionally, the authors postulate that it is advisable to keep mobile phones at a distance from the head, i.e. use, whenever possible, hands-free kits to reduce EMF exposure, both for drivers and passengers.
EN
Objectives: The aim of our study was to assess the health conditions and subjective symptoms of the inhabitants living in the base stations vicinity and to analyse the relationship between the complaints and level of exposure to electromagnetic fields (EMF). Materials and Methods: Our study was performed in housing estates located in five regions of Łódź. The electric field measurements were performed in the buildings located closest to the azimuth of the antennas. Respondents were selected by trained interviewers using an uniform procedure. The number of the households to be examined was set at a minimum of 420. The questionnaire contained: demographic data, occupational and environmental exposure to EMF, health condition, subjective complaints. Results were adjusted for confounders (age, gender, EMF at the workplace and EMF emitted by household equipment) using multiple regression model. Results: 181 men and 319 women from 500 households were examined. Electric field above 0.8 V/m was recorded in 12% of flats. There was no significant correlation between electric field strength and the distance of examined flats from the base stations. To make possible comparison with relevant literature, we analysed also the frequency of the reported symptoms vs. the distance. Headache was declared by 57% people, most frequently (36.4%) living 100–150 m away from the base station compared to people living at longer distances (p = 0.013). 24.4% subjects, mostly living at a distance above 150 m, declared impaired memory. Difference was statistically significant in comparison with people living at other distances (p = 0.004). Conclusions: The explanation why we did not find any correlation between the electric field strength and frequency of subjective symptoms but found a correlation between subjective symptoms and distance from base station needs further studies. Maybe new metrics of exposure assessment should be adopted for this purpose.
EN
Objectives: The aim of the study was to identify and assess electromagnetic radiofrequency radiation (EMRR) exposure in a workplace located in a publicly accessible environment, and represented by offices (where exposure is caused by various transmitters of local fixed indoor and outdoor wireless communication systems). Material and Methods: The investigations were performed in 45 buildings (in urban and rural areas in various regions of Poland), using frequency-selective electric field strength (E-field) exposimeters sensitive to the EMRR with a frequency range of 88–2500 MHz, split into 12 subbands corresponding to the operating frequencies of typical EMRR sources. The variability of the E-field was analyzed for each frequency range and the total level of exposure by statistical parameters of recorded exposimetric profiles: minimum, maximum, median values and 25–75th – percentiles. Results: The main sources of exposure to EMRR are mobile phone base transceiver stations (BTS) and radio-television transmitters (RTV). The frequency composition in a particular office depends on the building’s location. The E-field recorded in buildings in urban and rural areas from the outdoor BTS did not exceed respectively: medians – 0.19 and 0.05 V/m, 75th percentiles – 0.25 and 0.09 V/m. In buildings equipped with the indoor BTS antennas the E-field did not exceed: medians – 1 V/m, 75th percentiles – 1.8 V/m. Whereas in urban and rural areas, the median and 75th percentile values of the E-field recorded in buildings located near the RTV (within 1 km) did not exceed: 1.5 and 3.8 V/m or 0.4 and 0.8 V/m, for radio FM band or for TV bands, respectively. Conclusions: Investigations confirmed the practical applicability of the exposimetric measurements technique for evaluating parameters of worker’s exposure in both frequency- and time-domain. The presented results show EMRR exposure of workers or general public in locations comparable to offices to be well below international limits.
EN
Objectives: To assess the type and incidence of subjective symptoms related to the use of mobile phones in Polish users. Material and Methods: The study was conducted in 2005 using a questionnaire survey. Although it has been quite a long time, up to now, no such data have been published for Poland. The questionnaire consisted of 53 questions concerning sex, age, education, general health, characteristics of a mobile phone (hand-held, loud-speaking unit) as well as the habits associated with its use (frequency and duration of calls, text messages, etc.) and complaints associated with using a mobile phone. Results: As many as 1800 questionnaires were sent. The response was obtained from 587 subjects aged 32.6±11.3 (48.9% women, 51.1% men); the age did not differ significantly between men and women. The subjects owned a cell phone for an average of 3 years. Majority of the respondents used the phone intensively, i.e. daily (74%) or almost daily (20%). Headaches were reported significantly more often by the people who talked frequently and long in comparison with other users (63.2% of the subjects, p = 0.0029), just like the symptoms of fatigue (45%, p = 0.013). Also, the feeling of warmth around the ear and directly to the auricle was reported significantly more frequently by the intensive mobile phone users, compared with other mobile phone users (47.3%, p = 0.00004 vs. 44.6%, p = 0.00063, respectively). Most symptoms appeared during or immediately after a call and disappeared within 2 h after the call. Continuous headache, persisting for longer than 6 h since the end of a call, was reported by 26% of the subjects. Conclusions: Our results show that the mobile phone users may experience subjective symptoms, the intensity of which depends on the intensity of use of mobile phones.
EN
Introduction: This study attempted to determine the effect of a 1800 MHz electromagnetic field (EMF) (only carrier frequency) on thyroxine (T₄), triiodothyronine (T₃) and corticosterone (CORT) concentrations in the blood plasma of chick embryos, and to investigate the effect of electromagnetic field (EMF) exposure during embryogenesis on the level of these hormones in birds that are ready for slaughter. Material and Methods: Throughout the incubation period, embryos from the experimental group were exposed to a 1800 MHz EMF with power density of 0.1 W/m², 10 times during 24 h for 4 min. Blood samples were collected to determine T₄, T₃ and CORT concentrations on the 12th (E12) and 18th (E18) day of incubation, from newly hatched chicks (D1) and from birds ready for slaughter (D42). Results: The experiment showed that T₄ and T₃ concentrations decreased markedly and CORT levels increased in the embryos and in the newly hatched chicks exposed to EMF during embryogenesis. However, no changes were found in the level of the analyzed hormones in the birds ready for slaughter. Differences in T₄ and T₃ plasma concentrations between the EMF-exposed group and the embryos incubated without additional EMF were the highest in the newly hatched chicks, which may be indicative of the cumulative effect of electromagnetic field on the hypothalamo-pituitary-thyroid axis (HPT). Discussion: The obtained results suggest that additional 1800 MHz radio frequency electromagnetic field inhibits function of HPT axis, however, it stimulates hypothalamo- pituitary-adrenal axis by inducing adrenal steroidogenic cells to synthesize corticosterone. Further investigations are needed to elucidate the mechanisms by which radio EMFs affect HPT and HPA axis function in the chicken embryos.
EN
Background In the studies investigating the potential health effects of occupational exposure to electromagnetic fields (EMF), the key problem is the assessment of workers’ exposure. Electromagnetic fields exposure assessment requires determining maximum EMF levels, for the acute effect, and the dose absorbed, for the cumulative effect. A study was undertaken to determine EMF exposure in workers at broadcasting centers (BCs) in Poland. It was the first part of a comprehensive project on health effects of occupational exposure to EMF. Material and Methods The study was conducted in 4 selected BCs. Spot measurements of electric field strength (E), and the results of E measurements that were made in the past for occupational hygiene assessments, were used for determining workers’ exposure to electric field. The parameters considered were the maximum E value ($\text{E}_\text{max}$), the weighted average E value ($\text{E}_\text{avg}$) and the E lifetime dose ($\text{E}_\text{lifetime dose}$). Results In the group of workers examined, the E values did not exceed 16.7 V/m for Emax (the occupational exposure limit (OEL) for work shift in Poland is 20 V/m), 2.9 V/m for $\text{E}_\text{avg}$ and 1 500 000 (V/m)²×h for $\text{E}_\text{lifetime dose}$. Conclusions In view of the lack of dosimetry data, a retrospective assessment of BC workers’ exposure to very high frequency and ultra-high frequency EMF was conducted, which made it possible to estimate EMF lifetime dose for the workers. Since the EMF exposure levels at BCs did not exceed the admissible values, they can be considered safe to the workers’ health, according to the approach used for developing OELs for EMF exposure. Med Pr 2018;69(5):477–482
EN
Results of epidemiological studies on the association between use of mobile phone and brain cancer are ambiguous, as well as the results of 5 meta-analysis studies published to date. Since the last meta-analysis (2009), new case-control studies have been published, which theoretically could affect the conclusions on this relationship. Therefore, we decided to perform a new meta-analysis. We conducted a systematic review of multiple electronic data bases for relevant publications. The inclusion criteria were: original papers, case-control studies, published till the end of March 2014, measures of association (point estimates as odds ratio and confidence interval of the effect measured), data on individual exposure. Twenty four studies (26 846 cases, 50 013 controls) were included into the meta-analysis. A significantly higher risk of an intracranial tumor (all types) was noted for the period of mobile phone use over 10 years (odds ratio (OR) = 1.324, 95% confidence interval (CI): 1.028–1.704), and for the ipsilateral location (OR = 1.249, 95% CI: 1.022–1.526). The results support the hypothesis that long-term use of mobile phone increases risk of intracranial tumors, especially in the case of ipsilateral exposure. Further studies are needed to confirm this relationship. Int J Occup Med Environ Health 2017;30(1):27–43
EN
Background Low frequency magnetic field, inducing electrical field (Ein) inside conductive structures may directly affect the human body, e.g., by electrostimulation in the nervous system. In addition, the spatial distribution and level of Ein are disturbed in tissues neighbouring the medical implant. Material and Methods Numerical models of magneto-therapeutic applicator (emitting sinusoidal magnetic field of frequency 100 Hz) and the user of hearing implant (based on bone conduction: Bonebridge type – IS-BB or BAHA (bone anchorde hearing aid) type – IS-BAHA) were worked out. Values of Ein were analyzed in the model of the implant user’s head, e.g., physiotherapist, placed next to the applicator. Results It was demonstrated that the use of IS-BB or IS-BAHA makes electromagnetic hazards significantly higher (up to 4-fold) compared to the person without implant exposed to magnetic field heterogeneous in space. Hazards for IS-BAHA users are higher than those for IS-BB users. It was found that applying the principles of directive 2013/35/EU, at exposure to magnetic field below exposure limits the direct biophysical effects of exposure in hearing prosthesis users may exceed relevant limits. Whereas applying principles and limits set up by Polish labor law or the International Commission on Non-Ionizing Radiation Protection (ICNIRP) guidelines, the compliance with the exposure limits also ensures the compliance with relevant limits of electric field induced in the body of hearing implant user. Conclusions It is necessary to assess individually electromagnetic hazard concerning hearing implant users bearing in mind significantly higher hazards to them compared to person without implant or differences between levels of hazards faced by users of implants of various structural or technological solutions. Med Pr 2017;68(4):469–477
PL
Wstęp Pole magnetyczne małej częstotliwości, wywołując wewnątrz struktur elektrycznie przewodzących indukowane pole elektryczne (Ein), może bezpośrednio oddziaływać na funkcjonowanie organizmu, np. poprzez elektrostymulację układu nerwowego. Ponadto rozkład przestrzenny i natężenie Ein są zaburzone w sąsiedztwie elektroprzewodzących struktur implantu medycznego. Materiał i metody Opracowano numeryczne modele aplikatora do magnetoterapii, będącego źródłem pola magnetycznego sinusoidalnie zmiennego o częstotliwości 100 Hz, oraz użytkownika częściowo implantowanej protezy słuchu (implantu słuchowego wykorzystującego przewodnictwo kostne: typu Bonebridge (IS-BB) lub implantu słuchowego typu BAHA (IS-BAHA – bone anchored hearing aid, implant słuchu zakotwiczony w kości). Przeanalizowano wartości Ein w modelu głowy użytkownika implantu przebywającego obok aplikatora (np. fizjoterapeuty). Wyniki Wykazano, że używanie IS-BB lub IS-BAHA istotnie zwiększa (do ok. 4-krotnie) zagrożenia elektromagnetyczne jego użytkownika w porównaniu z osobą bez implantu, narażoną na niejednorodne przestrzennie pole magnetyczne. Zagrożenie dla użytkownika IS-BAHA jest większe niż użytkownika IS-BB. Stwierdzono, że przy zastosowaniu zasad oceny określonych w Dyrektywie 2013/35/UE w przypadku użytkowników implantów słuchowych przy narażeniu na pole niejednorodne słabsze od limitów indukcji magnetycznej może wystąpić przekroczenie limitów natężenia pola indukowanego w organizmie. Natomiast w przypadku stosowania wymagań i limitów określonych w polskim prawie pracy lub zaleceniach ICNIRP (International Commission on Non-Ionizing Radiation Protection – Międzynarodowa Komisja ds. Ochrony Przed Promieniowaniem Niejonizującym) dotrzymanie wymagań dotyczących poziomu ekspozycji zapewnia również dotrzymanie wymagań dotyczących odpowiednich limitów pola indukowanego w organizmie użytkownika implantu słuchowego. Wnioski Konieczne jest wykonanie indywidualnej oceny zagrożeń elektromagnetycznych dotyczących użytkowników implantów słuchowych ze względu na stwierdzone istotnie większe zagrożenia w stosunku do osób bez implantu oraz różnic w poziomie zagrożenia użytkowników implantów o odmiennych rozwiązaniach konstrukcyjnych czy technologicznych. Med. Pr. 2017;68(4):469–477
EN
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).
PL
W 2017 r. w Polsce rozpoczęto przygotowania do zapewnienia wszystkim obywatelom dostępu do internetu o prędkości co najmniej 30 Mb/s, a 50% gospodarstw domowych – o prędkości co najmniej 100 Mb/s. Cel ten ma być zrealizowany dzięki m.in. sieci radiokomunikacyjnej standardu piątej generacji (5G). W artykule przedstawiono zagadnienia związane z założeniami konstrukcji sieci 5G oraz oszacowano poziom ekspozycji ludności na pola elektromagnetyczne związane z racjonalnym użytkowaniem tych sieci. Przeanalizowano również, czy z technicznego punktu widzenia implementacja sieci 5G może zapewnić dotrzymanie obecnie dopuszczalnego w Polsce poziomu natężenia pola elektrycznego (7 V/m), przy jednoczesnym uwzględnieniu występującego obecnie w środowisku narażenia powodowanego przez anteny stacji bazowych telefonii komórkowej. Jest to przyczynek do trwającej dyskusji nad koniecznością zmiany obowiązujących w Polsce wymagań ograniczających poziom ekspozycji ludności na pola elektromagnetyczne. Analiza teoretyczna ekspozycji środowiska na pole elektromagnetyczne emitowane przez systemy 5G, przeprowadzona na podstawie dostępnej dokumentacji proponowanych standardów technicznych, pokazuje, że przy racjonalnym gospodarowaniu mocą uzyskanie oczekiwanej (zgodnej ze standardami 5G) jakości połączeń za pośrednictwem stacji bazowych zainstalowanych na zewnątrz budynków i wykorzystujących inteligentne systemy antenowe o sterowanych wiązkach będzie można utrzymać natężenie pola elektrycznego i gęstość mocy poniżej aktualnych wartości dopuszczalnych w miejscach dostępnych dla ludności (<7 V/m, <0,1 W/m2).
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