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1.
Radiat Prot Dosimetry ; 198(9-11): 771-777, 2022 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-36005948

RESUMO

In this paper, we deal with measurement of 222Rn emanation coefficient (Ke) of soils using an accumulation method. We created a database of Ke values of dried soils for various soil types and soil groups, classified by the size of soil particles. For 18 different soil samples we obtained the Ke values in range 0.083-0.234. The analysis of radon emanation dependence on moisture for seven of these samples shows two different trends which were related to soil texture (clays or sands). Soils with predominant sandy particles prove weak dependence on moisture and Ke values from minimum value (at zero moisture) do not increase much (max 15% increase on every 5% of moisture), for soils with majority of clayey particles the moisture can affect the Ke more significantly (increase up to 60%).


Assuntos
Poluentes Radioativos do Ar , Radônio , Poluentes Radioativos do Solo , Poluentes Radioativos do Ar/análise , Radônio/análise , Solo , Poluentes Radioativos do Solo/análise
2.
Radiat Prot Dosimetry ; 198(9-11): 778-784, 2022 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-36005959

RESUMO

Among the most important factors that influence radon emanation from soil particles is the soil moisture and grain size. Both components, in its own way, modify the length of a trajectory that radon atom pass through in a volume of the soil pores. To better understand their impact on an emanation, we have developed our own computer program that can simulate the 222Rn emanation process in the soil environment, using an idea of a multigrain model. In our case, the central, radium-bearing soil grain is surrounded by 1330 adjacent grains of the same size forming a cubic structure and the moisture in a space of the soil pores is differently distributed. The simulation process is based on a two different distribution of 226Ra in soil grains (homogenous and heterogenous), while several variants of the thickness of an escape layer are analyzed for grains of different sizes and moisture contents.


Assuntos
Rádio (Elemento) , Radônio , Radônio/análise , Solo
3.
Radiat Prot Dosimetry ; 198(9-11): 759-765, 2022 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-36005966

RESUMO

Several scientific studies have shown that high content of radon in the soil environment can be a precursor of increased indoor radon levels. Inhabited areas where elevated indoor radon concentration appears for natural (geogenic) reasons are commonly referred to as radon-prone areas. In this study, radon-prone areas in the Slovak Republic were predicted on the basis of radon potential maps after its specific rescaling. In total, 99 municipalities have been identified in Slovakia where the annual average indoor radon concentration is expected to exceed the reference level of 300 Bq m-3; five of those are even expected to exceed 1000 Bq m-3. In these municipalities it is then required to conduct a survey of indoor radon measurements. Compared with a nationwide survey, the proposed approach of searching for houses with potentially high radon exposure is more efficient.


Assuntos
Poluentes Radioativos do Ar , Poluição do Ar em Ambientes Fechados , Monitoramento de Radiação , Radônio , Poluentes Radioativos do Ar/análise , Poluição do Ar em Ambientes Fechados/análise , Radônio/análise , Eslováquia
4.
Radiat Prot Dosimetry ; 198(9-11): 766-770, 2022 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-36005972

RESUMO

In 17 kindergartens in Slovakia indoor radon survey was performed over a period of 1 y. In selected kindergartens also continuous monitoring of indoor radon activity concentration was conducted for ~2 weeks, as well as soil radon measurements. Annual average of indoor radon concentration, measured using track detectors, ranged between 75 and 1810 Bq m-3. Soil radon concentration ranged from 13 to 320 kBq m-3. The relationship between activity concentrations measured in soil air and indoors has a linear character.


Assuntos
Poluentes Radioativos do Ar , Poluição do Ar em Ambientes Fechados , Monitoramento de Radiação , Radônio , Poluentes Radioativos do Ar/análise , Poluição do Ar em Ambientes Fechados/análise , Habitação , Radônio/análise , Eslováquia , Solo
5.
Radiat Prot Dosimetry ; 198(9-11): 802-808, 2022 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-36005983

RESUMO

The aim of this work was to use the microdosimetric threshold energy model to study the effects of alpha-emitting 222Rn progeny on the probability of developing lung cancer. The results suggest that the radiation risk may increase by several times as the thickness of the surface layer decreases. The thicker the protective mucus layer and the deeper the sensitive target cells are located in the tissue, the less radiation damage the same dose produces. These findings have been applied to children of various ages. As children grow older, their lungs enlarge, the mucus layer thickens and the cells sensitive to radiation damage move deeper into the lung tissue, resulting in a reduction of radiation risk. The fraction of affected target cells is not only a function of dose but also of lung tissue depth. The results indicate that children can be several times more vulnerable to radiation than adults.


Assuntos
Neoplasias Pulmonares , Radônio , Criança , Humanos , Pulmão , Neoplasias Pulmonares/etiologia , Doses de Radiação , Radônio/efeitos adversos , Radônio/análise , Produtos de Decaimento de Radônio , Medição de Risco
6.
Radiat Prot Dosimetry ; 191(2): 160-165, 2020 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-33130896

RESUMO

Slovak Institute of Metrology received in 2016 funding for realisation of a set up of a radon chamber with AlphaGUARD as a secondary standard of 222Rn in air as one part of the project. This secondary standard will serve to provide the traceability for laboratories that deal with 222Rn measurements in environmental samples. This project is a response to the European Union legislation and provides metrological support for the development and implementation of the national radon action plan, which the member states of the European Union are committed to fulfil in accordance with Council Directive 2013/59/Euratom. During development of the radon chamber, the determination of its basic technical parameters, such as the exact determination of the container volume and the area of the inner walls of the radon chamber, many tightness tests of the chamber, the definition of homogeneous radon atmosphere parameters and bilateral comparisons, were realised.


Assuntos
Poluentes Radioativos do Ar , Monitoramento de Radiação , Radônio , Poluentes Radioativos do Ar/análise , Radônio/análise , Eslováquia
7.
Radiat Prot Dosimetry ; 191(2): 244-249, 2020 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-33123719

RESUMO

222Rn (radon) is an ever-present radioactive component of the surface layer of the atmosphere. The knowledge of the shape of radon activity concentration (RAC) time series has several important applications in atmospheric studies. This study presents the results of RAC analysis according to Garzon et al. approach during the years 1991-2009, as well as attempts to reconstruct the shape of composite diurnal RAC cycles using either Garzon et al. original approach or other methods. From this study, it follows that in order to accurately reconstruct the mean diurnal RAC cycles for individual months in our locality (Central European region), the parameters have to be calibrated by local RAC and measured global solar radiation data. The original Garzon et al. approach underestimates the amplitude of mean diurnal RAC cycles during April-August by up to 10%, and overestimates the amplitude during September-March by up to 25%.


Assuntos
Poluentes Radioativos do Ar , Monitoramento de Radiação , Radônio , Poluentes Radioativos do Ar/análise , Atmosfera , Radônio/análise
8.
Radiat Prot Dosimetry ; 191(2): 223-227, 2020 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-33123734

RESUMO

This case study provides a view of the behavior of radon in an uninhabited house, the likes of which were built in thousands in Slovakia between 1950 and 1990. In one room of the house that was in contact with the subsoil, an average annual radon activity concentration (RAC) as high as 1088 Bq m-3 was found. A high radon supply to this room from the subsoil was identified in the corner of the room, and this correlated very well with the temperature difference between indoor and outdoor air. In this room, an atypical annual variation of RAC was found, with a maximum in September (1600 Bq m-3). In the other rooms on the ground floor, RACs at the level of 400-500 Bq m-3 were detected. In the rooms on the first floor, RACs of up to ~200 Bq m-3 were found.


Assuntos
Poluentes Radioativos do Ar , Poluição do Ar em Ambientes Fechados , Monitoramento de Radiação , Radônio , Poluentes Radioativos do Ar/análise , Poluição do Ar em Ambientes Fechados/análise , Habitação , Radônio/análise , Eslováquia
9.
Risk Anal ; 40(2): 370-384, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31404471

RESUMO

After smoking, exposure to radon and its progeny is the second leading cause of lung cancer. The probability of inducing lung carcinomas by inhaled radon progeny depends on the deposited radiation dose, and is significantly affected by physiological and morphometric changes induced by smoking. Due to irritation of the airways, the inhalation of cigarette smoke leads to the hyperproduction of mucus. Two concurrent processes occur: on one hand, increased production of mucus protects the target cells against radiation damage; on the other hand, in the case of long-term smokers, a chronic lung obstruction develops, causing an increase in the radiation dose to the lungs. Depending on the duration and intensity of smoking, these processes contribute to the final radiation dose with different weights. The primary objective of this study was to investigate to what extent these smoke-induced changes can modify the resulting absorbed dose of inhaled radon progeny relative to healthy nonsmokers. Since the bronchial dose depends on the degree of lung tissue damage, we have used this dose as a tool for detecting the effects of smoking on the lung epithelium. In other words, the biological effect of radon served as a tracer of changes induced by smoking.


Assuntos
Pneumopatias/induzido quimicamente , Neoplasias Pulmonares/induzido quimicamente , Radônio/efeitos adversos , Fumar , Administração por Inalação , Humanos , Pulmão/efeitos da radiação , Neoplasias Induzidas por Radiação , Probabilidade , Doses de Radiação , Radiometria , Medição de Risco , Produtos do Tabaco
10.
Radiat Prot Dosimetry ; 186(2-3): 413-418, 2019 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-31832651

RESUMO

This paper presents the results of measurements of radon activity concentration (RAC) in spring waters and natural wells in three mountains of Slovakia (Strázov Mountains, Povazský Inovec and Little Carpathians). These mountains provide drinking water for inhabitants of surrounding towns and villages. Little Carpathians is the most seismically active area in Slovakia. Povazský Inovec, where 2 out of 11 uranium deposits of Slovakia are located, is interesting due to increased uranium mineralization. We have collected samples from more than 170 natural water sources, many of which exceed the guide value of 100 Bq l-1, with a maximum value of 274 Bq l-1. The median of these data (15 Bq l-1) is also higher than the national median in groundwater (11.6 Bq l-1). From the obtained data, we have created maps representing RAC of groundwaters for the whole territory. These maps were also compared with the geological maps.


Assuntos
Água Subterrânea/análise , Nascentes Naturais/análise , Monitoramento de Radiação/métodos , Radônio/análise , Poluentes Radioativos da Água/análise , Humanos , Eslováquia
11.
Radiat Prot Dosimetry ; 186(2-3): 397-400, 2019 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-31793636

RESUMO

Smoking modifies morphological and physiological parameters of the lungs. Due to the irritation of airways, the natural self-cleaning ability of the lungs is impaired. The mucus accumulates in the airways and various infections develop, leading to chronic bronchitis. After the cessation of smoking, the lungs of the smoker start to heal and regenerate. Cilia in the lungs start to grow again and cleanse the lungs, thus reducing the risk of infection. The regeneration of the lungs takes a long time and depends on the degree of lung damage due to smoking. The aim of this study was to reconstruct the evolution of this regeneration process in chronic smokers by using the biological effects of radon and its decay products. Thus, radon in this study served as a tracer of changes induced by smoking.


Assuntos
Pneumopatias Obstrutivas/diagnóstico , Pulmão/citologia , Modelos Biológicos , Radônio/análise , Regeneração , Fumar/efeitos adversos , Simulação por Computador , Humanos , Pneumopatias Obstrutivas/etiologia
12.
Radiat Prot Dosimetry ; 186(2-3): 401-405, 2019 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-31711196

RESUMO

Radon measurements were carried out in four kindergartens in Slovakia. RSKS detectors (Radosys Ltd., Hungary) and RamaRn (SUJCHBO, Czech Republic) were used for integral measurement in indoor air. AlphaGUARD (Saphymo, Germany) and TERA system (Tesla, Czech Republic) were used for continual measurement in indoor air. An annual variation with a maximum during the summer holidays was observed. Daily variation strongly depended on the ventilation of rooms. The average radon activity concentration per unit of time calculated from integral measurements was higher than that calculated for working time only.


Assuntos
Poluentes Radioativos do Ar/análise , Poluição do Ar em Ambientes Fechados/análise , Monitoramento de Radiação/métodos , Radônio/análise , Pré-Escolar , Humanos , Instituições Acadêmicas , Eslováquia
13.
Radiat Prot Dosimetry ; 186(2-3): 419-423, 2019 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-31912867

RESUMO

Continuous radon measurement in waters is an appropriate tool for the study of its variations as well as for the clarification and understanding of the factors that cause these changes. In addition, sudden changes in radon activity concentration (RAC) in groundwater can be used to identify geodynamic activities and earthquake predictions. In this paper, two measuring systems for continuous monitoring of RAC in waters are presented and tested. One of them was designed for water sources with a high yield; the second one operates with a constant volume of a sample using a different method of 222Rn release from water. We present our first laboratory tests of continuous measurement of RAC in tap waters as well as the variations of RAC observed during a week.


Assuntos
Água Subterrânea/análise , Monitoramento de Radiação/instrumentação , Monitoramento de Radiação/métodos , Radônio/análise , Poluentes Radioativos da Água/análise , Humanos
14.
J Environ Radioact ; 189: 79-92, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29626723

RESUMO

In practice, information about atmospheric stability is often obtained from discrete stability classes determined from routine meteorological observations. However, changing concentrations of the radioactive gas 222Rn present in the atmosphere are also considered a good indicator of vertical dispersion and atmospheric stability. A complex, in-depth analysis between these different approaches of atmospheric stability assessment has not been performed so far, and was the main motivation behind this study. The study presents atmospheric radon data measured in Bratislava (Slovakia) and stability indexes (SI) calculated according to a modified Turner method during a period of one year. Basic features of the diurnal and seasonal variations of these variables are discussed. It was found that the time series of radon activity concentration (RAC) lags approximately 5 h behind that of the Turner stability classes adjusted for temperate climate regions. Various time lags were also identified between RAC and meteorological variables used to determine the stability classes. Evaluation of seasonal trends revealed a low variability of mean monthly values of stability classes compared to the variability of mean monthly values of RAC. Another notable difference between RAC and stability indexes was found - while the stability index can both increase and decrease with wind speed, concentration of outdoor radon was never observed to increase with increasing wind speed. In spite of the mentioned discrepancies, the time series of RAC and SI are generally in a good agreement. This is especially true if one compares the deviations of RAC and SI from their mean daily values, when the differences in their seasonal variability are eliminated. Deviations of RAC can be used to calculate diurnal variations of stability indexes. Analysis of a complete year of data also revealed a roughly linear relationship between average values of RAC and calculated stability indexes, because in large datasets random processes tend to cancel each other out.


Assuntos
Poluentes Radioativos do Ar/análise , Monitoramento de Radiação/métodos , Radônio/análise , Atmosfera/química
15.
Radiat Prot Dosimetry ; 177(1-2): 207-212, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-28981812

RESUMO

In this article, the effective dose to the population from natural sources of ionizing radiation in the vicinity of Mochovce nuclear power plant in Slovakia is presented. All major contributions to the effective dose were taken into account, including the contributions from gamma radiation of soil and rocks, cosmic radiation, and indoor and outdoor radon and thoron. On the basis of recent indoor radon measurements in Slovak cities and publicly available data about radon concentration in the soil air, a roughly linear relationship was found between these variables. Consequently, the annual effective dose from indoor radon and thoron was conservatively estimated. For the area of interest, a map of conservatively estimated potential effective doses was created. For the villages in the vicinity of Mochovce, the conservatively estimated effective dose to the population from natural sources ranged from 5.4 to 14.6 mSv, which is four orders of magnitude higher than the contribution of radioactive discharges from Mochovce nuclear power plant.


Assuntos
Poluentes Radioativos do Ar/análise , Exposição Ambiental/análise , Centrais Nucleares , Monitoramento de Radiação/métodos , Radioisótopos/análise , Radiação Cósmica , Raios gama , Humanos , Exposição à Radiação , Radiação Ionizante , Radônio/análise , Eslováquia
16.
Radiat Prot Dosimetry ; 177(1-2): 95-98, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-29036677

RESUMO

The measurements of radon concentration were carried out in kindergartens of V4 countries (Hungary, Poland and Slovakia). RSKS detectors (Radosys Ltd., Hungary) were used for integrating measurement in indoor air. In total, 67 rooms in 20 kindergartens were measured. The survey was carried out in two periods from October 2015 to March 2016. The results show that radon concentration is less than 300 Bq m-3 in approximately 86.0% of cases in the first period and in 82.1% of cases in second period. However, rooms in kindergartens with radon concentration exceeding 1000 Bq m-3 were found in Slovakia.


Assuntos
Poluentes Radioativos do Ar/análise , Poluição do Ar em Ambientes Fechados/análise , Monitoramento de Radiação/métodos , Instituições Acadêmicas , Pré-Escolar , Feminino , Humanos , Hungria , Masculino , Polônia , Radônio/análise , Eslováquia
17.
J Environ Radioact ; 166(Pt 1): 27-35, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27020174

RESUMO

Variations of aerosol radionuclides (2001-2015) in the ground-level air in Bratislava (Slovakia) showed 7Be maxima in spring/early summer and minima in winter, however, an inverse trend was observed for 210Pb, 137Cs and 40K. A decreasing amplitude and splitting of summer maxima for 7Be in the last years has been found. A temporal behavior of the 7Be/210Pb activity ratio showed higher levels during warm seasons due to vertical convection of air masses from higher altitudes. The 137Cs activity concentration in the surface air between 2003 and 2010 was decreasing with an effective half-life of 1.9 ± 0.3 years. The yearly average 137Cs concentrations during 2009-2014 were almost constant, disturbed only by the Fukushima accident in 2011. The increased atmospheric 137Cs and 40K levels observed during the autumn-winter season may be due to surface soil resuspension, biomass burning and radionuclide transport by winds. Seasonal variations of 222Rn activity concentrations were found with maxima at the end of autumn and in winter, and minima in spring. The variability of the average annual course of 222Rn has been larger than that of 210Pb. The 210Pb/222Rn activity ratio was highest at the end of winter and in the spring, while from June to December remained nearly constant. More intensive atmospheric mixing in spring months caused a decrease in the 222Rn activity concentration, while the aerosol component of the atmosphere has been affected mainly during the autumn and winter seasons. The mean residence time of aerosols in the atmosphere was calculated using the 210Pb/222Rn method to be 4.5 ± 0.9 days.


Assuntos
Poluentes Radioativos do Ar/análise , Monitoramento de Radiação , Aerossóis/análise , Atmosfera/química , Meia-Vida , Estações do Ano , Eslováquia
18.
Appl Radiat Isot ; 110: 124-128, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26774389

RESUMO

The indoor radon measurements were carried out in 123 residential buildings and 33 schools in Visegrad countries (Slovakia, Hungary and Poland). In 13.2% of rooms radon concentration exceeded 300Bqm(-3), the reference value recommended in the Council Directive 2013/59/EURATOM. Indoor radon in houses shows the typical radon behavior, with a minimum in the summer and a maximum in the winter season, whereas in 32% of schools the maximum indoor radon was reached in the summer months.


Assuntos
Poluentes Radioativos do Ar/análise , Poluição do Ar em Ambientes Fechados/análise , Radônio/análise , Habitação , Humanos , Hungria , Polônia , Instituições Acadêmicas , Estações do Ano , Eslováquia , Inquéritos e Questionários
19.
Radiat Prot Dosimetry ; 160(1-3): 222-5, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24714111

RESUMO

Radon activity concentration in the soil air in the area of Faculty of Mathematics, Physics and Informatics (FMPI) in Bratislava, Slovak Republic, has been continuously monitored since 1994. Long-term measurements at a depth of 0.8 m and short-term measurements at a depth of 0.4 m show a high variability in radon activity concentrations in the soil. The analysis of the data confirms that regular daily changes in radon activity concentration in the soil air depend on the daily changes in atmospheric pressure. It was also found that the typical annual courses of the radon activity concentration in the soil air (with summer minima and winter maxima) were disturbed by mild winter and heavy summer precipitation. Influence of precipitation on the increase in the radon activity concentration in the soil air was observed at a depth of 0.4 m and subsequently at a depth of 0.8 m.


Assuntos
Poluentes Radioativos do Ar/análise , Monitoramento de Radiação , Radônio/análise , Estações do Ano , Poluentes Radioativos do Solo/análise , Humanos , Eslováquia
20.
Radiat Prot Dosimetry ; 145(2-3): 325-8, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21460367

RESUMO

Measurements of radon activity concentration (RAC) were made in two localities of Slovakia. The first one is located on the campus of Comenius University in Bratislava, where radon has been monitored since 1991. The second area is situated in the city of Nováky (midwest Slovakia, ∼150 km from Bratislava). The localities have a different orography. RAC was measured continuously by large-volume scintillation chambers. The outdoor air was sampled at a height of 1.5 m above the ground. Time courses of RAC in both localities have a similar character. The correlation coefficients between RAC in Bratislava and Nováky was quite high (R(2) = 0.45). However, RACs in Nováky were found out to be about two times higher (∼12.1 Bq m(-3)) than in Bratislava.


Assuntos
Poluentes Radioativos do Ar/análise , Poluição do Ar/análise , Monitoramento Ambiental , Monitoramento de Radiação , Radônio/análise , Humanos , Eslováquia
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