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Kumara KS, Karunakara N, Mayya YS. Development of a " 222Rn incremented method" for the rapid determination of air exchange rate using soil gas. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2023; 257:107076. [PMID: 36493636 PMCID: PMC9723537 DOI: 10.1016/j.jenvrad.2022.107076] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Revised: 11/12/2022] [Accepted: 11/16/2022] [Indexed: 06/17/2023]
Abstract
The air exchange rate (AER) is a critical parameter that governs the levels of exposure to indoor pollutants impacting occupants' health. It has been recognized as a crucial metric in spreading COVID-19 disease through airborne routes in shared indoor spaces. Assessing the AER in various human habitations is essential to combat such detrimental exposures. In this context, the development of techniques for the rapid determination of the AER has assumed importance. AER is generally determined using CO2 concentration decay data or other trace gas injection methods. We have developed a new method, referred to as the "222Rn incremented method", in which 222Rn from naturally available soil gas was injected into the workplace for a short duration (∼30 min), homogenized and the profile of decrease of 222Rn concentration was monitored for about 2 h to evaluate AER. The method was validated against the established 222Rn time-series method. After ascertaining the suitability of the method, several experiments were performed to measure the AER under different indoor conditions. The AER values, thus determined, varied in a wide range of 0.36-4.8 h-1 depending upon the ventilation rate. The potential advantages of the technique developed in this study over conventional methods are discussed.
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Affiliation(s)
- K Sudeep Kumara
- Centre for Advanced Research in Environmental Radioactivity, Mangalore University, Mangalagangothri, 574199, Mangalore, India.
| | - N Karunakara
- Centre for Advanced Research in Environmental Radioactivity, Mangalore University, Mangalagangothri, 574199, Mangalore, India
| | - Y S Mayya
- Department of Chemical Engineering, IIT-Bombay, Mumbai, 400 076, India
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2
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Tchorz-Trzeciakiewicz DE, Kozłowska B, Walencik-Łata A. Seasonal variations of terrestrial gamma dose, natural radionuclides and human health. CHEMOSPHERE 2023; 310:136908. [PMID: 36270528 DOI: 10.1016/j.chemosphere.2022.136908] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Revised: 10/11/2022] [Accepted: 10/13/2022] [Indexed: 06/16/2023]
Abstract
The aim of the research was to study seasonal variations in gamma radiation and the statistical significance of these variations. Moreover, we compared in-situ and laboratory analyses of uranium, thorium, radium and potassium K-40 contents. Exposure to a low level of radiation is a minor (but still is) contributor to overall cancer risk therefore we compared doses generated by gamma radiation with overall cancer risk. The research was performed in SW Poland in two granitoid massifs -Strzelin and Karkonosze. The in-situ measurements were performed seasonally using gamma-ray spectrometer Exploranium with BGO detector and Radiometer RK-100. The laboratory measurements were performed using spectrometer with HPGe detector Canberra-Packard and alpha spectrometry technique. The general trend of seasonal variations of natural radionuclides, terrestrial ambient gamma dose (TGDR) and ambient gamma dose rate (AGDR) was difficult to identify. We noticed slightly increased values of all analysed parameters in warmer seasons, and lower in colder, although there were some exceptions. These exceptions were induced by precipitation and varied soil water content, but variations were mostly not statistically significant. The statistically important deviation from the trend was registered only in equivalent uranium data when the survey was carried out during or just after intensive precipitation. We observed a good positive correlation between in-situ and laboratory results (TGDR in situ/Lab r = 0.696), therefore, we recommend using in-situ measurements in a dense measuring grid before collecting selected soil samples to better evaluate the level of natural radiation in the environment. The average ambient gamma dose in the Karkonosze Massif was 0.52 mSv y-1 whereas in the Strzelin Massif was 0.39 mSv y-1. The overall cancer risk in Karkonoski county is higher than in Strzelin county. A connection between increased gamma radiation and higher overall cancer risk is possible but should be examined during more elaborated research.
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Affiliation(s)
| | - B Kozłowska
- University of Silesia in Katowice, August Chełkowski Institute of Physics, 75 Pułku Piechoty 1, 41-500, Chorzów, Poland
| | - A Walencik-Łata
- University of Silesia in Katowice, August Chełkowski Institute of Physics, 75 Pułku Piechoty 1, 41-500, Chorzów, Poland
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3
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Banríon MH, Elío J, Crowley QG. Using geogenic radon potential to assess radon priority area designation, a case study around Castleisland, Co. Kerry, Ireland. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2022; 251-252:106956. [PMID: 35780671 DOI: 10.1016/j.jenvrad.2022.106956] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Revised: 06/21/2022] [Accepted: 06/22/2022] [Indexed: 06/15/2023]
Abstract
Globally, indoor radon exposure is the leading cause of lung cancer in non-smokers and second most common cause after tobacco smoking. Soil-gas radon is the main contributor to indoor radon, but its spatial distribution is highly variable, which poses certain challenges for mapping and predicting radon anomalies. Measurement of indoor radon typically takes place over long periods of time (e.g. 3 months) and is seasonally adjusted to an annual average concentration. In this article we investigate the suitability of using soil-gas radon and soil-permeability measurements for rapid radon risk assessments at local scale. The area of Castleisland, Co. Kerry was chosen as a case study due to availability of indoor radon data and the presence of significant radon anomalies. In total, 135 soil-gas and permeability measurements were collected and complemented with 180 indoor radon measurements for an identical 6 km2 area. Both soil-gas and indoor radon concentrations ranged from very low (<10 kBqm-3, 0.1 Bqm-3) to anomalously high (>1433 kBqm-3, 65,000 Bqm-3) values. Our method classifies almost 50% of the area as a high radon potential area, and allows assessment of geogenic controls on radon distribution by including other geological variables. Cumulatively, the percentage of indoor radon variance explained by soil-gas radon concentration, bedrock geology, subsoil permeability and Quaternary geology is 34% (16%, 10%, 4% and 4% respectively). Soil-gas and indoor radon anomalies are associated with black shales, whereas the presence of karst and geological faults are other contributing factors. Sampling of radon soil-gas and soil permeability, used in conjunction with other geogenic data, can therefore facilitate rapid designation of radon priority areas. Such an approach demonstrates the usefulness of high-resolution geogenic maps in predicting indoor radon risk categories when compared to the application of indoor radon measurements alone. This method is particularly useful to assess radon potential in areas where indoor radon measurements are sparse or lacking, with particular application to rural areas, land rezoned for residential use, or for sites prior to building construction.
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Affiliation(s)
- M H Banríon
- Geology Department, School of Natural Sciences, Trinity College, Dublin 2, Ireland.
| | - J Elío
- Department of Planning, Aalborg University Copenhagen, Copenhagen, Denmark.
| | - Q G Crowley
- Geology Department, School of Natural Sciences, Trinity College, Dublin 2, Ireland.
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4
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Farai IP, Fajemiroye JA, Oni OM, Aremu AA. Artificial neural network modeling of soil gas radon concentration on different lithologies for Southwest Nigeria. JOURNAL OF RADIATION RESEARCH AND APPLIED SCIENCES 2022. [DOI: 10.1016/j.jrras.2022.08.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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Didier TSS, Yerima Abba H, Valentin V, Alidou M. Soil gas radon, indoor radon and its diurnal variation in the northern region of Cameroon. ISOTOPES IN ENVIRONMENTAL AND HEALTH STUDIES 2022; 58:402-419. [PMID: 35905287 DOI: 10.1080/10256016.2022.2102617] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Accepted: 06/01/2022] [Indexed: 06/15/2023]
Abstract
Soil gas radon and indoor radon measurements have been carried out in Mayo-Louti and Benoué Divisions in northern Cameroon. Concentrations of radon in soil have been measured using Markus 10 at the depth of about 1 m. Radon concentration in soil varies from 0.9 to 13.8 kBq m-3 with a mean value of 4.6 kBq m-3. Average daily indoor radon concentrations measured with RadonEye+2 detectors vary from 7 to 60 Bq m-3 with an average of 17 Bq m-3. Indoor radon concentrations measured with passive RADTRAK detectors range between 15 and 104 Bq m-3 with a geometric value of 38 Bq m-3 and a geometric standard deviation of 1.5. This geometric value is lower than the value of 30 Bq m-3 given by UNSCEAR. Indoor radon inhalation dose ranges between 0.28 and 1.97 mSv a-1 with geometric value of 0.72 mSv a-1 (at 0.03 standard deviation). Outdoor radon inhalation ranges between 0.02 and 0.26 mSv a-1 with a mean value of 0.09 mSv a-1. The total annual effective dose due to indoor and outdoor radon exposure for this study area is 0.81 mSv a-1, less than 1.15 mSv a-1 the world average value given by UNSCEAR. There is no significant radiological risk for the inhabitants.
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Affiliation(s)
- Takoukam Soh Serge Didier
- Nuclear Physics Laboratory, Faculty of Science, University of Yaoundé I, Yaoundé, Cameroon
- National Radiation Protection Agency, Yaoundé, Cameroon
| | - Hamadou Yerima Abba
- Research Centre for Nuclear Science and Technology, Institute of Geological and Mining Research, Yaoundé, Cameroon
| | - Vaskanglang Valentin
- Atom and Radiation Laboratory, Faculty of Science, University of Maroua, Maroua, Cameroon
| | - Mohamadou Alidou
- National Advanced School of Engineering, University of Maroua, Maroua, Cameroon
- Department of Physics, Faculty of Science, University of Douala, Douala, Cameroon
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6
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Ajiboye Y, Isinkaye MO, Badmus GO, Faloye OT, Atoiki V. Pilot groundwater radon mapping and the assessment of health risk from heavy metals in drinking water of southwest, Nigeria. Heliyon 2022; 8:e08840. [PMID: 35146162 PMCID: PMC8818932 DOI: 10.1016/j.heliyon.2022.e08840] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2021] [Revised: 01/14/2022] [Accepted: 01/24/2022] [Indexed: 01/09/2023] Open
Abstract
Radon and heavy metals are sources of groundwater pollution and are identified as potential carcinogens. Southwest Nigeria's populace mostly relies on groundwater source for drinking. This study aims to map radon distribution in groundwater of southwest Nigeria and to determine the health risk of radon and heavy metal in drinking water. Radon concentrations of 145 groundwater samples were measured using RAD7 electronic radon detector and heavy metal concentrations of 52 groundwater samples were measured using atomic absorption spectrophotometer. Radon concentration distributions were delineated using geographical information system. Radon concentration of water samples ranges between 1.6 Bq l−1 and 271 Bq l−1 with an average value of 35.9 ± 38.4 Bq l−1. The average groundwater radon concentration is higher than US-EPA recommended level of 11.1 Bq l−1 but lower than the WHO recommended limit of 100 Bq l−1. The estimated average annual effective radiation doses to infants, children, and adults are 29 μSvy−1, 41 μSvy−1 and 92 μSvy−1 respectively. The radon distribution map of the study area reveals regions of high, medium, and low groundwater radon concentrations. The average concentration values of heavy metals in groundwater samples are of the order Mn > Zn > Pb > Cu > Cr > Ni > Cd. 84% of groundwater exhibits good to excellent quality in terms of heavy metal pollution. However, about 16% of the samples which lie in the sedimentary regions of Ogun and Lagos States exhibit poor to very poor quality. Overall, ingestion of groundwater in the study area may not pose a serious health hazards from radon ingestion and heavy metal toxicity.
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Affiliation(s)
- Yinka Ajiboye
- Department of Mathematical and Physical Sciences, Afe Babalola University, Ado-Ekiti, Nigeria
| | | | - Ganiyu Olabode Badmus
- Department of Mathematical and Physical Sciences, Afe Babalola University, Ado-Ekiti, Nigeria
- Corresponding author.
| | - Oluwaseun Temitope Faloye
- Department of Food and Biosystems Engineering, Afe Babalola University, Ado Ekiti, Nigeria
- Department of Water Resources Management and Agrometeorology, Federal University, Oye-Ekiti, Nigeria
| | - Vincent Atoiki
- Department of Science Technology, Federal Polytechnic, Ado-Ekiti, Nigeria
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7
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Ryzhakova N, Stavitskaya K, Plastun S. The problems of assessing radon hazard of development sites in the Russian Federation and the Czech Republic. RADIAT MEAS 2022. [DOI: 10.1016/j.radmeas.2021.106681] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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8
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Petermann E, Meyer H, Nussbaum M, Bossew P. Mapping the geogenic radon potential for Germany by machine learning. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 754:142291. [PMID: 33254926 DOI: 10.1016/j.scitotenv.2020.142291] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2020] [Revised: 08/12/2020] [Accepted: 09/07/2020] [Indexed: 06/12/2023]
Abstract
The radioactive gas radon (Rn) is considered as an indoor air pollutant due to its detrimental effects on human health. In fact, exposure to Rn belongs to the most important causes for lung cancer after tobacco smoking. The dominant source of indoor Rn is the ground beneath the house. The geogenic Rn potential (GRP) - a function of soil gas Rn concentration and soil gas permeability - quantifies what "earth delivers in terms of Rn" and represents a hazard indicator for elevated indoor Rn concentration. In this study, we aim at developing an improved spatial continuous GRP map based on 4448 field measurements of GRP distributed across Germany. We fitted three different machine learning algorithms, multivariate adaptive regression splines, random forest and support vector machines utilizing 36 candidate predictors. Predictor selection, hyperparameter tuning and performance assessment were conducted using a spatial cross-validation where the data was iteratively left out by spatial blocks of 40 km*40 km. This procedure counteracts the effect of spatial auto-correlation in predictor and response data and minimizes dependence of training and test data. The spatial cross-validated performance statistics revealed that random forest provided the most accurate predictions. The predictors selected as informative reflect geology, climate (temperature, precipitation and soil moisture), soil hydraulic, soil physical (field capacity, coarse fraction) and soil chemical properties (potassium and nitrogen concentration). Model interpretation techniques such as predictor importance as well as partial and spatial dependence plots confirmed the hypothesized dominant effect of geology on GRP, but also revealed significant contributions of the other predictors. Partial and spatial dependence plots gave further valuable insight into the quantitative predictor-response relationship and its spatial distribution. A comparison with a previous version of the German GRP map using 1359 independent test data indicates a significantly better performance of the random forest based map.
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Affiliation(s)
- Eric Petermann
- Federal Office for Radiation Protection (BfS), Section Radon and NORM, Berlin, Germany.
| | - Hanna Meyer
- Westfälische Wilhelms-Universität Münster, Institute of Landscape Ecology, Münster, Germany
| | - Madlene Nussbaum
- Bern University of Applied Sciences (BFH), School of Agricultural, Forest and Food Sciences, (HAFL), Zollikofen, Switzerland
| | - Peter Bossew
- Federal Office for Radiation Protection (BfS), Section Radon and NORM, Berlin, Germany
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9
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Ćujić M, Janković Mandić L, Petrović J, Dragović R, Đorđević M, Đokić M, Dragović S. Radon-222: environmental behavior and impact to (human and non-human) biota. INTERNATIONAL JOURNAL OF BIOMETEOROLOGY 2021; 65:69-83. [PMID: 31955264 DOI: 10.1007/s00484-020-01860-w] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Revised: 12/24/2019] [Accepted: 01/06/2020] [Indexed: 06/10/2023]
Abstract
As an inert radioactive gas, 222Rn could be easily transported to the atmosphere via emanation, migration, or exhalation. Research measurements pointed out that 222Rn activity concentration changes during the winter and summer months, as well as during wet and dry season periods. Changes in radon concentration can affect the atmospheric electric field. At the boundary layer near the ground, short-lived daughters of 222Rn can be used as natural tracers in the atmosphere. In this work, factors controlling 222Rn pathways in the environment and its levels in soil gas and outdoor air are summarized. 222Rn has a short half-life of 3.82 days, but the dose rate due to radon and its radioactive progeny could be significant to the living beings. Epidemiological studies on humans pointed out that up to 14% of lung cancers are induced by exposure to low and moderate concentrations of radon. Animals that breed in ground holes have been exposed to the higher doses due to radiation present in soil air. During the years, different dose-effect models are developed for risk assessment on human and non-human biota. In this work are reviewed research results of 222Rn exposure of human and non-human biota.
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Affiliation(s)
- Mirjana Ćujić
- University of Belgrade, Vinča Institute of Nuclear Sciences, POB 522, Belgrade, Serbia.
| | | | - Jelena Petrović
- University of Belgrade, Vinča Institute of Nuclear Sciences, POB 522, Belgrade, Serbia
| | - Ranko Dragović
- Department of Geography, University of Niš, Faculty of Sciences and Mathematics, POB 224, Niš, Serbia
| | - Milan Đorđević
- Department of Geography, University of Niš, Faculty of Sciences and Mathematics, POB 224, Niš, Serbia
| | - Mrđan Đokić
- Department of Geography, University of Niš, Faculty of Sciences and Mathematics, POB 224, Niš, Serbia
| | - Snežana Dragović
- University of Belgrade, Vinča Institute of Nuclear Sciences, POB 522, Belgrade, Serbia
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10
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Karunakara N, Shetty T, Sahoo BK, Kumara KS, Sapra BK, Mayya YS. An innovative technique of harvesting soil gas as a highly efficient source of 222Rn for calibration applications in a walk-in type chamber: part-1. Sci Rep 2020; 10:16547. [PMID: 33024139 PMCID: PMC7538554 DOI: 10.1038/s41598-020-73320-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2020] [Accepted: 09/14/2020] [Indexed: 11/27/2022] Open
Abstract
The paper describes a novel technique to harvest 222Rn laden air from soil gas of natural origin as a highly efficient source of 222Rn for calibration applications in a walk-in type 222Rn calibration chamber. The technique makes use of a soil probe of about 1 m to draw soil gas, through a dehumidifier and a delay volume, using an air pump to fill the calibration chamber. 222Rn concentration in the range of a few hundred Bq m-3 to a few tens of kBq m-3 was easily attained in the chamber of volume 22.7 m3 within a short pumping duration of 1 h. A new technique referred to as "semi-dynamic mode of operation" in which soil gas is injected into the calibration chamber at regular intervals to compensate for the loss of 222Rn due to decay and leak is discussed. Harvesting soil gas has many important advantages over the traditional methods of 222Rn generation for calibration experiments using finite sources such as solid flow-through, powdered emanation, and liquid sources. They are: (1) soil gas serves as an instantaneous natural source of 222Rn, very convenient to use unlike the high strength 226Ra sources used in the calibration laboratories, and has no radiation safety issues, (2) does not require licensing from the regulatory authority, and (3) it can be used continuously as a non-depleting reservoir of 222Rn, unlike other finite sources. The newly developed technique would eliminate the need for expensive radioactive sources and thereby offers immense application in a variety of day to day experiments-both in students and research laboratories.
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Affiliation(s)
- N Karunakara
- Centre for Advanced Research in Environmental Radioactivity (CARER), Mangalore University, Mangalagangothri, Mangalore, 574 199, India.
| | - Trilochana Shetty
- Centre for Advanced Research in Environmental Radioactivity (CARER), Mangalore University, Mangalagangothri, Mangalore, 574 199, India
| | - B K Sahoo
- Radiological Physics and Advisory Division, Bhabha Atomic Research Centre, Trombay, Mumbai, 400 085, India
| | - K Sudeep Kumara
- Centre for Advanced Research in Environmental Radioactivity (CARER), Mangalore University, Mangalagangothri, Mangalore, 574 199, India
| | - B K Sapra
- Radiological Physics and Advisory Division, Bhabha Atomic Research Centre, Trombay, Mumbai, 400 085, India
| | - Y S Mayya
- Department of Chemical Engineering, IIT-Bombay, Mumbai, 400 076, India
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Shetty T, Mayya YS, Kumara KS, Sahoo BK, Sapra BK, Karunakara N. A periodic pumping technique of soil gas for 222Rn stabilization in large calibration chambers: part 2-theoretical formulation and experimental validation. Sci Rep 2020; 10:16548. [PMID: 33024133 PMCID: PMC7538436 DOI: 10.1038/s41598-020-71872-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Accepted: 06/29/2020] [Indexed: 12/02/2022] Open
Abstract
In an adjoining publication, we demonstrated the novel technique to harvest soil gas of natural origin as a highly efficient source of 222Rn for calibration applications in a large volume 222Rn calibration chamber. Its advantages over the use of conventional high strength 226Ra sources, such as the capability to serve as a non-depleting reservoir of 222Rn and achieve the desired concentration inside the calibration chamber within a very short time, devoid of radiation safety issues in source handling and licensing requirements from the regulatory authority, were discussed in detail. It was also demonstrated that stability in the 222Rn concentration in large calibration chambers could be achieved within ± 20% deviation from the desired value through a semi-dynamic mode of injection in which 222Rn laden air was periodically pumped to compensate for its loss due to leak and decay. The necessity of developing a theory for determining the appropriate periodicity of pumping was realized to get good temporal stability with a universally acceptable deviation of ≤ ± 10% in the 222Rn concentration. In this paper, we present a mathematical formulation to determine the injection periods (injection pump ON and OFF durations) for the semi-dynamic operation to achieve long term temporal stability in the 222Rn concentration in the chamber. These computed pumping parameters were then used to efficiently direct the injection of soil gas into the chamber. We present the mathematical formulation, and its experimental validations in a large volume calibration chamber (22 m3). With this, the temporal stability of 222Rn concentration in the chamber was achieved with a deviation of ~ 3% from the desired value.
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Affiliation(s)
- Trilochana Shetty
- Centre for Advanced Research in Environmental Radioactivity (CARER), Mangalore University, Mangalagangothri, Mangalore, 574 199, India
| | - Y S Mayya
- Department of Chemical Engineering, IIT-Bombay, Mumbai, 400 076, India
| | - K Sudeep Kumara
- Centre for Advanced Research in Environmental Radioactivity (CARER), Mangalore University, Mangalagangothri, Mangalore, 574 199, India
| | - B K Sahoo
- Radiological Physics and Advisory Division, Bhabha Atomic Research Centre (BARC), Trombay, Mumbai, 400 085, India
| | - B K Sapra
- Radiological Physics and Advisory Division, Bhabha Atomic Research Centre (BARC), Trombay, Mumbai, 400 085, India
| | - N Karunakara
- Centre for Advanced Research in Environmental Radioactivity (CARER), Mangalore University, Mangalagangothri, Mangalore, 574 199, India.
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Jónás J, Somlai J, Csordás A, Tóth-Bodrogi E, Kovács T. Radiological survey of the covered and uncovered drilling mud depository. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2018; 188:30-37. [PMID: 29103632 DOI: 10.1016/j.jenvrad.2017.10.020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Revised: 10/31/2017] [Accepted: 10/31/2017] [Indexed: 06/07/2023]
Abstract
In petroleum engineering, the produced drilling mud sometimes contains elevated amounts of natural radioactivity. In this study, a remediated Hungarian drilling mud depository was investigated from a radiological perspective. The depository was monitored before and after a clay layer was applied as covering. In this study, the ambient dose equivalent rate H*(10) of the depository has been measured by a Scintillator Probe (6150AD-b Dose Rate Meter). Outdoor radon concentration, radon concentration in soil gas, and in situ field radon exhalation measurements were carried out using a pulse-type ionization chamber (AlphaGUARD radon monitor). Soil gas permeability (k) measurements were carried out using the permeameter (RADON-JOK) in situ device. Geogenic radon potentials were calculated. The radionuclide content of the drilling mud and cover layer sample has been determined with an HPGe gamma-spectrometer. The gamma dose rate was estimated from the measured radionuclide concentrations and the results were compared with the measured ambient dose equivalent rate. Based on the measured results before and after covering, the ambient dose equivalent rates were 76 (67-85) nSv/h before and 86 (83-89) nSv/h after covering, radon exhalation was 9 (6-12) mBq/m2s before and 14 (5-28) mBq/m2s after covering, the outdoor radon concentrations were 11 (9-16) before and 13 (10-22) Bq/m3after covering and the soil gas radon concentrations were 6 (3-8) before and 24 (14-40) kBq/m3 after covering. Soil gas permeability measurements were 1E-11 (7E-12-1E-11) and 1E-12 (5E-13-1E-12) m2 and the calculated geogenic radon potential values were 6 (3-8) and 12 (6-21) before and after the covering. The main radionuclide concentrations of the drilling mud were CU-238 12 (10-15) Bq/kg, CRa-226 31 (18-40) Bq/kg, CTh-232 35 (33-39) Bq/kg and CK-40 502 (356-673) Bq/kg. The same radionuclide concentrations in the clay were CU-238 31 (29-34) Bq/kg, CRa-226 45 (40-51) Bq/kg, CTh-232 58 (55-60) Bq/kg and CK-40 651 (620-671) Bq/kg. According to our results, the drilling mud depository exhibits no radiological risk from any radiological aspects (radon, radon exhalation, gamma dose, etc.); therefore, long term monitoring activity is not necessary from the radiological point of view.
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Affiliation(s)
- Jácint Jónás
- Institute of Radiochemistry and Radioecology, University of Pannonia, 10 Egyetem Str., H-8200 Veszprém, Hungary; NORM Hungary Kft., Hungary
| | - János Somlai
- Institute of Radiochemistry and Radioecology, University of Pannonia, 10 Egyetem Str., H-8200 Veszprém, Hungary
| | - Anita Csordás
- Institute of Radiochemistry and Radioecology, University of Pannonia, 10 Egyetem Str., H-8200 Veszprém, Hungary
| | - Edit Tóth-Bodrogi
- Institute of Radiochemistry and Radioecology, University of Pannonia, 10 Egyetem Str., H-8200 Veszprém, Hungary
| | - Tibor Kovács
- Institute of Radiochemistry and Radioecology, University of Pannonia, 10 Egyetem Str., H-8200 Veszprém, Hungary; Social Organization for Radioecological Cleanliness, Hungary.
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Jónás J, Somlai J, Tóth-Bodrogi E, Hegedűs M, Kovács T. Study of a remediated coal ash depository from a radiological perspective. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2017; 173:75-84. [PMID: 28041855 DOI: 10.1016/j.jenvrad.2016.11.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2016] [Revised: 11/07/2016] [Accepted: 11/10/2016] [Indexed: 06/06/2023]
Abstract
Coal-fired power plants play a significant role in the production of electricity. The Ra-226 concentration of coals mined in the Ajka region can reach up to 3000 Bq/kg. This study focuses on the effects of a Hungarian (Ajka) remediated coal ash depository on the environment and the effectiveness of the cover layer. During the remediation, a method patented in Hungary was used, in which the upper layer of the depository, which had settled like concrete, was ploughed and mixed with woodchips before being planted with vegetation. The gamma dose rate H*(10) of the depository and its vicinity was measured using Automess 6150AD-b at 32 points, surface Rn-222 exhalation at 19 points and air radon concentration at 34 points; at 32 points, soil gas radon content was measured with AlphaGUARD and soil permeability with RADON-JOK. The nuclide content of nine samples was determined using an HPGe gamma spectrometer and their Rn-222 exhalation rates were measured using the AlphaGUARD. H*(10) was 290 (130-525) nSv/h at the covered depository; CRa-226 was 1997 Bq/kg, 960 Bq/kg and 104 Bq/kg for the ash, cover layer and background soil respectively. CRn-222 in the soil was 25-161 kBq/m3, and soil gas permeability K was between 6.4E-13 and 1.80E-11 m2. The radon exhalation of the uncovered and covered depository was 259-1100 mBq/m2s. The exhalation and emanation coefficients of the samples were 0.05-0.32 mBq/kgs and 8-22%. The effects of vegetation on the migration of radon were also examined. The results show that the Ajka coal ash depository involves higher radiological risk than that reported by previously published studies on depositories. The applied cover layer halved the field radon exhalation; in addition, the vegetation reduced the convective airflow and, with this, the migration of Rn.
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Affiliation(s)
- Jácint Jónás
- University of Pannonia, Institute of Radiochemistry and Radioecology, Veszprém, Hungary; Social Organization for Radioecological Cleanliness, Veszprém, Hungary
| | - János Somlai
- University of Pannonia, Institute of Radiochemistry and Radioecology, Veszprém, Hungary
| | - Edit Tóth-Bodrogi
- University of Pannonia, Institute of Radiochemistry and Radioecology, Veszprém, Hungary
| | - Miklós Hegedűs
- University of Pannonia, Institute of Radiochemistry and Radioecology, Veszprém, Hungary
| | - Tibor Kovács
- University of Pannonia, Institute of Radiochemistry and Radioecology, Veszprém, Hungary; Social Organization for Radioecological Cleanliness, Veszprém, Hungary.
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14
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Huxtable D, Read D, Shaw G. Measuring radon-222 in soil gas with high spatial and temporal resolution. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2017; 167:36-42. [PMID: 27843065 DOI: 10.1016/j.jenvrad.2016.11.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2016] [Revised: 10/24/2016] [Accepted: 11/01/2016] [Indexed: 06/06/2023]
Abstract
In order to exploit 222Rn as a naturally-occurring tracer in soils we need to sample and measure radon isotopes in soil gas with high spatial and temporal resolution, without disturbing in situ activity concentrations and fluxes. Minimisation of sample volume is key to improving the resolution with which soil gas can be sampled; an analytical method is then needed which can measure radon with appropriate detection limits and precision for soil gas tracer studies. We have designed a soil gas probe with minimal internal dead volume to allow us to sample soil gas volumes of 45 cm3. Radon-222 is extracted from these samples into a mineral oil-based scintillation cocktail before counting on a conventional liquid scintillation counter. A detection limit of 320 Bq m-3 (in soil gas) is achievable with a 1 h count. This could be further reduced but, in practice, is sufficient for our purpose since 222Rn in soil gas typically ranges from 2000-50,000 Bq m-3. The method is simple and provides several advantages over commonly used field-portable instruments, including smaller sample volumes, speed of deployment and reliability under field conditions. The major limitation is the need to count samples in a liquid scintillation counter within 2-3 days of collection, due to the short (3.824 day) radioactive half-life of 222Rn. The method is not applicable to the very short-lived (55 s half-life) 220Rn.
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Affiliation(s)
- Darren Huxtable
- University of Nottingham, School of Biosciences, Sutton Bonington Campus, Leicestershire, LE12 5RD, UK
| | - David Read
- Loughborough University, Department of Chemistry, Ashby Road, Loughborough, Leicestershire, LE11 3TU, UK
| | - George Shaw
- University of Nottingham, School of Biosciences, Sutton Bonington Campus, Leicestershire, LE12 5RD, UK
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Petersell V, Täht-Kok K, Karimov M, Milvek H, Nirgi S, Raha M, Saarik K. Radon in the soil air of Estonia. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2017; 166:235-241. [PMID: 27554705 DOI: 10.1016/j.jenvrad.2016.08.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2015] [Revised: 07/13/2016] [Accepted: 08/02/2016] [Indexed: 06/06/2023]
Abstract
Several investigations in Estonia during 1996¬-1999 have shown that permissible level (200 Bq/m3) of radon (222Rn) in indoor air is exceeded in 33% of the inspected dwellings. This makes Estonia one of the five countries with highest radon risk in Europe (Fig 1). Due to correlation between the soil radon risk level and radon concentration in houses, small scale radon risk mapping of soil air was carried out (one study point per 70-100 km2). It turned out that one-third of Estonian mainland has high radon risk potential, where radon concentration in soil air exceeds safe limit of 50 kBq/m3. In order to estimate radon content in soil air, two different methods developed in Sweden were used simultaneously. Besides measuring radon content from soil air at the depth of 80 cm with an emanometer (RnM), maximum potential content of radon in soil (RnG) was estimated based on the rate of eU (226Ra) concentration in soil, which was acquired by using gamma-ray spectrometer. Mapping and following studies revealed that simultaneously measured RnG and RnM in study points may often differ. To inspect the cause, several monitoring points were set up in places with different geological conditions. It appeared that unlike the RnG content, which remains close to average level in repeated measurements, the RnM content may differ more than three times periodically. After continuous observations it turned out that concentration of directly measured radon depended on various factors being mostly controlled by mineral composition of soil, properties of topsoil as well as different factors influencing aeration of soil. The results of Rn monitoring show that reliable level of radon risk in Estonian soils can only be acquired by using calculated Rn-concentration in soil air based on eU content and directly measured radon content of soil air in combination with interpreting specific geological and geochemical situations in the study points.
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Affiliation(s)
| | | | - Mark Karimov
- Geological Survey of Estonia, 12618 Tallinn, Estonia
| | - Heli Milvek
- Geological Survey of Estonia, 12618 Tallinn, Estonia
| | - Siim Nirgi
- Geological Survey of Estonia, 12618 Tallinn, Estonia
| | - Margus Raha
- Geological Survey of Estonia, 12618 Tallinn, Estonia
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Ciotoli G, Voltaggio M, Tuccimei P, Soligo M, Pasculli A, Beaubien SE, Bigi S. Geographically weighted regression and geostatistical techniques to construct the geogenic radon potential map of the Lazio region: A methodological proposal for the European Atlas of Natural Radiation. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2017; 166:355-375. [PMID: 27241368 DOI: 10.1016/j.jenvrad.2016.05.010] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2015] [Revised: 05/07/2016] [Accepted: 05/12/2016] [Indexed: 06/05/2023]
Abstract
In many countries, assessment programmes are carried out to identify areas where people may be exposed to high radon levels. These programmes often involve detailed mapping, followed by spatial interpolation and extrapolation of the results based on the correlation of indoor radon values with other parameters (e.g., lithology, permeability and airborne total gamma radiation) to optimise the radon hazard maps at the municipal and/or regional scale. In the present work, Geographical Weighted Regression and geostatistics are used to estimate the Geogenic Radon Potential (GRP) of the Lazio Region, assuming that the radon risk only depends on the geological and environmental characteristics of the study area. A wide geodatabase has been organised including about 8000 samples of soil-gas radon, as well as other proxy variables, such as radium and uranium content of homogeneous geological units, rock permeability, and faults and topography often associated with radon production/migration in the shallow environment. All these data have been processed in a Geographic Information System (GIS) using geospatial analysis and geostatistics to produce base thematic maps in a 1000 m × 1000 m grid format. Global Ordinary Least Squared (OLS) regression and local Geographical Weighted Regression (GWR) have been applied and compared assuming that the relationships between radon activities and the environmental variables are not spatially stationary, but vary locally according to the GRP. The spatial regression model has been elaborated considering soil-gas radon concentrations as the response variable and developing proxy variables as predictors through the use of a training dataset. Then a validation procedure was used to predict soil-gas radon values using a test dataset. Finally, the predicted values were interpolated using the kriging algorithm to obtain the GRP map of the Lazio region. The map shows some high GRP areas corresponding to the volcanic terrains (central-northern sector of Lazio region) and to faulted and fractured carbonate rocks (central-southern and eastern sectors of the Lazio region). This typical local variability of autocorrelated phenomena can only be taken into account by using local methods for spatial data analysis. The constructed GRP map can be a useful tool to implement radon policies at both the national and local levels, providing critical data for land use and planning purposes.
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Affiliation(s)
- G Ciotoli
- Istituto di Geologia Ambientale e Geoingegneria, Consiglio Nazionale delle Ricerche - IGAG-CNR, Area della Ricerca di Roma1, Rome, Italy; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma 2, Rome, Italy.
| | - M Voltaggio
- Istituto di Geologia Ambientale e Geoingegneria, Consiglio Nazionale delle Ricerche - IGAG-CNR, Area della Ricerca di Roma1, Rome, Italy
| | - P Tuccimei
- Università degli Studi "Roma Tre", Dipartimento di Scienze, Rome, Italy
| | - M Soligo
- Università degli Studi "Roma Tre", Dipartimento di Scienze, Rome, Italy
| | - A Pasculli
- Department of Engineering and Geology, University G. d'Annunzio, Chieti-Pescara, Chieti, Italy
| | - S E Beaubien
- Dipartimento di Scienze della Terra, Sapienza Università di Roma, Rome, Italy
| | - S Bigi
- Dipartimento di Scienze della Terra, Sapienza Università di Roma, Rome, Italy
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Ohno M, Okamoto K, Umegaki K, Fujiyoshi R. Results of simultaneous monitoring of soil 222Rn and moisture at different depths in a forest site in Fukushima Prefecture, Japan. J Radioanal Nucl Chem 2016. [DOI: 10.1007/s10967-016-4946-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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18
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Li X, Xu X, Li W, Wang F, Hai C. Preliminary study on the variation of radon-222 inside greenhouse of Shouguang county, China. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2016; 153:120-125. [PMID: 26771243 DOI: 10.1016/j.jenvrad.2015.12.024] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Revised: 12/18/2015] [Accepted: 12/28/2015] [Indexed: 06/05/2023]
Abstract
Studies on radon have become the focus of indoor radiation. In this study, we chose greenhouse to be the study field, the research aims to: (1) explore the diurnal variation of radon concentration inside greenhouse in Shouguang county, China; (2) pre-analyze the relationship between radon concentration, temperature and relative humidity, and shed light on the radon behavior characteristic inside greenhouse; (3) verify the feasibility of calculating radon radiation dose by using short-period detected radon concentrations in typical months in Shouguang county. The following conclusions were drawn. Firstly, the average radon levels in typical months in Shouguang county are all much higher than that in ordinary dwellings in China, diurnal and seasonal variations in radon levels are observed inside greenhouse. Secondly, temperature and relative humidity may play a role indirectly through affecting soil moisture and other factors. The mechanism need to be further studied. Thirdly, radon concentrations detected in typical months are still useful in preliminary estimation of radon radiation dose for vegetable-plant farmers in Shouguang county.
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Affiliation(s)
- Xiaohong Li
- Department of Toxicology, School of Military Preventive Medicine, The Fourth Military Medical University, Xi'an 710032, Shanxi, China; College of Public Health and Management, Weifang Medical University, Weifang 261053, Shandong, China
| | - Xianqin Xu
- Affiliated Hospital of Weifang Medical University, Yuhe Road, 261031 Weifang, Shandong Province, China
| | - Wanwei Li
- College of Public Health and Management, Weifang Medical University, Weifang 261053, Shandong, China.
| | - Fei Wang
- College of Public Health and Management, Weifang Medical University, Weifang 261053, Shandong, China
| | - Chunxu Hai
- Department of Toxicology, School of Military Preventive Medicine, The Fourth Military Medical University, Xi'an 710032, Shanxi, China.
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Arvela H, Holmgren O, Hänninen P. Effect of soil moisture on seasonal variation in indoor radon concentration: modelling and measurements in 326 Finnish houses. RADIATION PROTECTION DOSIMETRY 2016; 168:277-290. [PMID: 25899611 PMCID: PMC4884879 DOI: 10.1093/rpd/ncv182] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2014] [Revised: 03/06/2015] [Accepted: 03/07/2015] [Indexed: 05/30/2023]
Abstract
The effect of soil moisture on seasonal variation in soil air and indoor radon is studied. A brief review of the theory of the effect of soil moisture on soil air radon has been presented. The theoretical estimates, together with soil moisture measurements over a period of 10 y, indicate that variation in soil moisture evidently is an important factor affecting the seasonal variation in soil air radon concentration. Partitioning of radon gas between the water and air fractions of soil pores is the main factor increasing soil air radon concentration. On two example test sites, the relative standard deviation of the calculated monthly average soil air radon concentration was 17 and 26%. Increased soil moisture in autumn and spring, after the snowmelt, increases soil gas radon concentrations by 10-20 %. In February and March, the soil gas radon concentration is in its minimum. Soil temperature is also an important factor. High soil temperature in summer increased the calculated soil gas radon concentration by 14%, compared with winter values. The monthly indoor radon measurements over period of 1 y in 326 Finnish houses are presented and compared with the modelling results. The model takes into account radon entry, climate and air exchange. The measured radon concentrations in autumn and spring were higher than expected and it can be explained by the seasonal variation in the soil moisture. The variation in soil moisture is a potential factor affecting markedly to the high year-to-year variation in the annual or seasonal average radon concentrations, observed in many radon studies.
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Affiliation(s)
- H Arvela
- STUK-Radiation and Nuclear Safety Authority, P.O. Box 14, Helsinki FIN-00881, Finland
| | - O Holmgren
- STUK-Radiation and Nuclear Safety Authority, P.O. Box 14, Helsinki FIN-00881, Finland
| | - P Hänninen
- Geological Survey of Finland, Betonimiehenkuja 4, Espoo FIN-02150, Finland
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20
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Mentes G, Eper-Pápai I. Investigation of temperature and barometric pressure variation effects on radon concentration in the Sopronbánfalva Geodynamic Observatory, Hungary. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2015; 149:64-72. [PMID: 26207821 DOI: 10.1016/j.jenvrad.2015.07.015] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2015] [Revised: 07/14/2015] [Accepted: 07/16/2015] [Indexed: 05/22/2023]
Abstract
Radon concentration variation has been monitored since 2009 in the artificial gallery of the Sopronbánfalva Geodynamic Observatory, Hungary. In the observatory, the radon concentration is extremely high, 100-600 kBq m(-3) in summer and some kBq m(-3) in winter. The relationships between radon concentration, temperature and barometric pressure were separately investigated in the summer and winter months by Fast Fourier Transform, Principal Component Analysis, Multivariable Regression and Partial Least Square analyses in different frequency bands. It was revealed that the long-period radon concentration variation is mainly governed by the temperature (20 kBq m(-1) °C(-1)) both in summer and winter. The regression coefficients between long-period radon concentration and barometric pressure are -1.5 kBq m(-3) hPa(-1) in the summer and 5 kBq m(-3) hPa(-1) in the winter months. In the 0.072-0.48 cpd (cycles per day) frequency band the effect of the temperature is about -1 kBq m(-3) °C(-1) and that of the barometric pressure is -5 kBq m(-3) hPa(-1) in summer and -0.5 kBq m(-3) hPa(-1) in winter. In the high frequency range (>0.48 cpd) all regression coefficients are one order of magnitude smaller than in the range of 0.072-0.48 cpd. Fast Fourier Transform of the radon concentration, temperature and barometric pressure time series revealed S1, K1, P1, S2, K2, M2 tidal constituents in the data and weak O1 components in the radon concentration and barometric pressure series. A detailed tidal analysis, however, showed that the radon tidal components are not directly driven by the gravitational force but rather by solar radiation and barometric tide. Principal Component Analysis of the raw data was performed to investigate the yearly, summer and winter variability of the radon concentration, temperature and barometric pressure. In the summer and winter periods the variability does not change. The higher variability of the radon concentration compared to the variability of the temperature and the barometric pressure shows that besides the temperature and barometric pressure variations other agents, e.g. natural ventilation of the observatory, wind, etc. also play an important role in the radon concentration variation.
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Affiliation(s)
- Gyula Mentes
- Geodetic and Geophysical Institute, Research Centre for Astronomy and Earth Sciences, Hungarian Academy of Sciences, Csatkai E. u. 6-8., H-9400 Sopron, Hungary.
| | - Ildikó Eper-Pápai
- Geodetic and Geophysical Institute, Research Centre for Astronomy and Earth Sciences, Hungarian Academy of Sciences, Csatkai E. u. 6-8., H-9400 Sopron, Hungary.
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Barbosa SM, Lopes F, Correia AD, Barbosa S, Pereira AC, Neves LF. Temporal variability of radon in a remediated tailing of uranium ore processing--the case of Urgeiriça (central Portugal). JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2015; 142:14-23. [PMID: 25618233 DOI: 10.1016/j.jenvrad.2014.12.015] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2014] [Revised: 12/10/2014] [Accepted: 12/27/2014] [Indexed: 06/04/2023]
Abstract
Radon monitoring at different levels of the cover of the Urgeiriça tailings shows that the sealing is effective and performing as desired in terms of containing the strongly radioactive waste resulting from uranium ore processing. However, the analysis of the time series of radon concentration shows a very complex temporal structure, particularly at depth, including very large and fast variations from a few tens of kBq m(-3) to more than a million kBq m(-3) in less than one day. The diurnal variability is strongly asymmetric, peaking at 18 h/19 h and decreasing very fast around 21 h/22 h. The analysis is performed for summer and for a period with no rain in order to avoid the potential influence of precipitation and related environmental conditions on the radon variability. Analysis of ancillary measurements of temperature, relative humidity, wind speed and wind direction, as well as atmospheric pressure reanalysis data shows that the daily averaged radon concentration in the taillings material is anti-correlated with the atmospheric pressure and that the diurnal amplitude is associated with the magnitude of atmospheric pressure daily oscillations.
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Affiliation(s)
- S M Barbosa
- University of Lisbon, Instituto Dom Luiz, Lisboa, Portugal.
| | - F Lopes
- University of Lisbon, Instituto Dom Luiz, Lisboa, Portugal
| | - A D Correia
- EDM, Empresa de Desenvolvimento Mineiro, SA, Portugal
| | - S Barbosa
- EDM, Empresa de Desenvolvimento Mineiro, SA, Portugal
| | - A C Pereira
- IMAR, Department of Earth Sciences, University of Coimbra, Portugal
| | - L F Neves
- IMAR, Department of Earth Sciences, University of Coimbra, Portugal
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23
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Szabó KZ, Jordan G, Horváth Á, Szabó C. Mapping the geogenic radon potential: methodology and spatial analysis for central Hungary. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2014; 129:107-120. [PMID: 24412775 DOI: 10.1016/j.jenvrad.2013.12.009] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2013] [Revised: 12/02/2013] [Accepted: 12/12/2013] [Indexed: 06/03/2023]
Abstract
A detailed geogenic radon potential (GRP) mapping based on field soil gas radon and soil gas permeability measurements was carried out in this study. A conventional continuous variable approach was used in this study for GRP determination and to test its applicability to the selected area of Hungary. Spatial pattern of soil gas radon concentration, soil permeability and GRP and the relationship between geological formations and these parameters were studied by performing detailed spatial analysis. Exploratory data analysis revealed that higher soil gas radon activity concentration and GRP characterizes the mountains and hills than the plains. The highest values were found in the proluvial-deluvial sediments, rock debris on the downhill slopes eroded from hills. Among the Quaternary sediments, which characterize the study area, the fluvial sediment has the highest values, which are also located in the hilly areas. The lowest values were found in the plain areas covered by drift sand, fluvioeolic sand, fluvial sand and loess. As a conclusion, radon is related to the sediment cycle in the study area. A geogenic radon risk map was created, which assists human health risk assessment and risk reduction since it indicates the potential of the source of indoor radon. The map shows that low and medium geogenic radon potential characterizes the study area in central Hungary. High risk occurs only locally. The results reveal that Quaternary sediments are inhomogeneous from a radon point of view, fluvial sediment has medium GRP, whereas the other rock formations such as drift sand, fluioeolic sand, fluvial sand and loess, found in the study area, have low GRP.
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Affiliation(s)
- Katalin Zsuzsanna Szabó
- Lithosphere Fluid Research Laboratory, Department of Petrology and Geochemistry, Eötvös University, Pázmány Péter sétány 1/C, 1117 Budapest, Hungary.
| | - Gyozo Jordan
- Institute for Geological and Geochemical Research, Research Centre for Astronomy and Earth Sciences, Hungarian Academy of Sciences, Budaörsi út 45, 1112 Budapest, Hungary.
| | - Ákos Horváth
- Department of Atomic Physics, Eötvös University, Pázmány Péter sétány 1/A, 1117 Budapest, Hungary.
| | - Csaba Szabó
- Lithosphere Fluid Research Laboratory, Department of Petrology and Geochemistry, Eötvös University, Pázmány Péter sétány 1/C, 1117 Budapest, Hungary.
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