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Mitev K, Sabot B, Pierre S, Lépy MC, Cassette P. Towards a radon-in-water primary standard at LNHB. Appl Radiat Isot 2023; 201:111013. [PMID: 37688905 DOI: 10.1016/j.apradiso.2023.111013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Revised: 08/30/2023] [Accepted: 09/01/2023] [Indexed: 09/11/2023]
Abstract
Despite widespread radon-in-water measurements, no primary radon-in-water standards currently exist. This work aims to bridge this gap by developing a system to produce radon-in-water reference materials. The system relies on cryogenic, loss-free transfer of radon, which is standardized through defined solid angle measurements, to a radon standard in water. It allows for preparation of liquid scintillation and gamma-ray spectrometry samples with traceable radon-in-water concentrations. The system's design, functionality, and the results of pilot performance tests are described.
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Affiliation(s)
- Krasimir Mitev
- Sofia University "St. Kliment Ohridski", Faculty of Physics, 1164, Sofia, Bulgaria.
| | - Benoit Sabot
- Université Paris-Saclay, CEA, LIST, Laboratoire National Henri Becquerel (LNE-LNHB), 91120, Palaiseau, France
| | - Sylvie Pierre
- Université Paris-Saclay, CEA, LIST, Laboratoire National Henri Becquerel (LNE-LNHB), 91120, Palaiseau, France
| | - Marie-Christine Lépy
- Université Paris-Saclay, CEA, LIST, Laboratoire National Henri Becquerel (LNE-LNHB), 91120, Palaiseau, France
| | - Philippe Cassette
- Sofia University "St. Kliment Ohridski", Faculty of Physics, 1164, Sofia, Bulgaria
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2
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Pujol L. Validation of a method for measuring radon-222 in water using two-phase liquid scintillation counting according to the ISO/IEC 17025 criteria. J Radioanal Nucl Chem 2022. [DOI: 10.1007/s10967-022-08313-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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3
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Radium interference during radon measurements in water: comparison of one- and two-phase liquid scintillation counting. ACTA ACUST UNITED AC 2021; 72:205-215. [PMID: 34587671 PMCID: PMC8576753 DOI: 10.2478/aiht-2021-72-3480] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2020] [Accepted: 09/01/2021] [Indexed: 11/20/2022]
Abstract
Assessment of radiation exposure to drinking, surface, and groundwater and of the associated health risks calls for accurate and precise 226Ra and 222Rn measurements. One method that fits the bill is liquid scintillation counting (LSC), which allows measurements in one-phase (homogenous) or two-phase samples. The aim of our study was to compare the measurement efficiency with both variations in Niška Banja spa water, known for its elevated 222Rn content to get a better insight into the stability and behaviour of the samples and 226Ra interference in samples spiked with 226Ra with 222Rn measurement. 226Ra interference was more evident in homogenous, one-phase and much lower in two-phase samples. However, one-phase samples offer more accurate indirect 226Ra measurements. Water-immiscible cocktails (in two-phase samples) have shown a limited capacity for receiving 222Rn generated by Ra decay from the aqueous to organic phase when 222Rn/226Ra equilibrium is reached. We have also learned that samples with naturally high 222Rn content should not be spiked with 226Ra activities higher than the ones found in native samples and that calibration of two-phase samples can be rather challenging if measurements span over longer time. Further research would require much lower 226Ra activities for spiking to provide more practical answers to questions arising from the demonstrated phenomena.
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4
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Rotich CK, Hashim NO, Chege MW, Nyambura C. MEASUREMENT OF RADON ACTIVITY CONCENTRATION IN UNDERGROUND WATER OF BURETI SUB-COUNTY OF KERICHO COUNTY KENYA. RADIATION PROTECTION DOSIMETRY 2020; 192:56-60. [PMID: 33294927 DOI: 10.1093/rpd/ncaa193] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Revised: 09/29/2020] [Accepted: 10/25/2020] [Indexed: 06/12/2023]
Abstract
The activity concentration of radon in underground water of Bureti sub-county was measured using liquid scintillating counter device. The average radon activity concentration in all the water samples was 12.41 Bql-1. The maximum and minimum activity concentrations of radon were 22.5 and 4.57 Bql-1, respectively. In total, 53% of the total samples analysed had radon concentration levels above the US Environmental Protection Agency-recommended limit of 11.1 Bql-1. The annual dose received by an individual as a result of waterborne radon was determined according to the United Nations Scientific Committee on the Effect of Atomic Radiation reports and was found to be 33.23 𝜇Svy-1. All the samples recorded a value <100 𝜇Svy-1 recommended by the World Health Organization and the European Union council.
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Affiliation(s)
- Charles K Rotich
- Department of Physics, Kenyatta University, PO Box 43844-00100, Nairobi, Kenya
| | - Nadir O Hashim
- Department of Physics, Kenyatta University, PO Box 43844-00100, Nairobi, Kenya
| | - Margaret W Chege
- Department of Physics, Kenyatta University, PO Box 43844-00100, Nairobi, Kenya
| | - Catherine Nyambura
- Department of Physics, Kenyatta University, PO Box 43844-00100, Nairobi, Kenya
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5
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Nikolov J, Stojković I, Todorović N, Tenjović B, Vuković S, Knežević J. Evaluation of different LSC methods for 222Rn determination in waters. Appl Radiat Isot 2018; 142:56-63. [PMID: 30248591 DOI: 10.1016/j.apradiso.2018.09.013] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Revised: 08/19/2018] [Accepted: 09/12/2018] [Indexed: 10/28/2022]
Abstract
Monitoring of 222Rn in drinking or surface waters, as well as in groundwater has been performed regularly in connection with geological, hydrogeological and hydrological surveys and health hazard studies. Liquid scintillation counting (LSC) is often preferred analytical method for 222Rn measurements in waters as it allows multiple-sample automatic analysis. LSC method implies mixing of water samples with organic scintillation cocktail, which triggers radon diffusion from the aqueous into an organic phase for which it has a much greater affinity, eliminating the possibility of radon emanation in that manner. The main aim of this paper is calibration of the liquid scintillation counter Qunatulus 1220™ for measuring of radon in water and evaluation of two different methods (one-phase and two-phase) in order to obtain the most suitable LSC technique for radon in water measurement. In this study four different scintillation cocktails were tested: one miscible (Ultima Gold AB) and three immiscible (High Efficiency Mineral Oil Scintillator, Opti-Fluor O and Ultima Gold F). Evaluation of presented methods was based on obtained detection efficiency and achieved Minimal Detectable Activity (MDA) values. Comparison of presented methods, accuracy and precision, as well as different scintillation cocktail's performance, was considered from results of measurements of 226Ra spiked water samples with known activity and environmental samples. LSC results were compared with the results of radon in water measurement obtained by alpha spectrometer RAD7. Calibration was done as a dependence of calibration factor (CF) from Pulse Shape Analysis (PSA). According to the obtained results, with proper adjustment of calibration parameters, both methods could be used for radon in water measurements. The obtained MDA values for all four scintillation cocktails are very low, less than 0.1 Bq l-1 for measuring time of 300 min.
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Affiliation(s)
- Jovana Nikolov
- University of Novi Sad, Faculty of Sciences, Department of Physics, Novi Sad, Serbia.
| | - Ivana Stojković
- University of Novi Sad, Faculty of Technical Science, Novi Sad, Serbia
| | - Nataša Todorović
- University of Novi Sad, Faculty of Sciences, Department of Physics, Novi Sad, Serbia
| | - Branislava Tenjović
- University of Novi Sad, Faculty of Sciences, Department of Chemistry, Novi Sad, Serbia
| | - Srđan Vuković
- University of Novi Sad, Faculty of Sciences, Department of Physics, Novi Sad, Serbia
| | - Jovana Knežević
- University of Novi Sad, Faculty of Sciences, Department of Physics, Novi Sad, Serbia
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6
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Kato T, Janik M, Kanda R, Ishikawa T, Kawase M, Kawamoto T. Environmentally Friendly Measurement of Airborne Radon Using a Nonvolatile Liquid Scintillation Absorbent. HEALTH PHYSICS 2018; 115:203-211. [PMID: 29957685 DOI: 10.1097/hp.0000000000000851] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The practicality of using a liquid scintillation method with a nonvolatile liquid scintillation absorbent for the measurement of airborne Rn (radon) in a residence was examined. The relationship between the radioactivity absorbed by the liquid scintillation absorbent and the radon concentration in the air was investigated in a calibrated walk-in radon chamber. The equivalent radioactivity of radon was calculated for Po radioactivity immediately after radioactive equilibrium was attained using successive decay equations via alpha-particle spectrometry based on the 1 h, indirect, selective measurement of the Po alpha-particle spectrum generated after sampling radon. We confirmed that the amounts of radon absorbed in the liquid scintillation absorbent were proportional to the radon concentration in the air. The calibration curve that exhibited reliable quantitative linearity from 500 to 8,000 Bq m in air was extrapolated to the region between 0 and 500 Bq m using the least-squares method with data from 500 to 8,000 Bq m. The validity of the extrapolated curve at less than 500 Bq m was confirmed by comparison of the measured radon concentrations in the room and atmosphere with those determined using an existing ionization chamber. Variations in the absorption of radon were observed due to changes in temperature and humidity. The health and environmental safety of nonvolatile liquid scintillation absorbent was also considered.
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Affiliation(s)
- Takahisa Kato
- Radioisotope Research Center, Kyoto University, Yoshidakonoe-cho, Sakyo-ku, Kyoto, 606-8501, Japan
| | - Miroslaw Janik
- National Institutes for Quantum and Radiological Sciences and Technology, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba, 263-8555, Japan
| | - Reiko Kanda
- National Institutes for Quantum and Radiological Sciences and Technology, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba, 263-8555, Japan
| | - Tetsuo Ishikawa
- Department of Radiation Physics and Chemistry, Fukushima Medical University, Hikariga-oka 1, Fukushima, 960-1295, Japan
| | - Masaya Kawase
- Faculty of Bioscience, Nagahama Institute of Bio-science and Technology, 1266 Tamura, Nagahama, Shiga 526-0829, Japan
| | - Takuo Kawamoto
- Radioisotope Research Center, Kyoto University, Yoshidakonoe-cho, Sakyo-ku, Kyoto, 606-8501, Japan
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Bhade SPD, Reddy PJ, Anilkumar S, Singhal RK, Rao DD. Calibration and optimization of alpha-beta separation procedures for determination of radium/radon in single- and two-phase liquid scintillation systems. J Radioanal Nucl Chem 2017. [DOI: 10.1007/s10967-017-5643-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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8
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Lopes I, Vesterbacka P, Kelleher K. Comparison of radon (Rn-222) concentration in Portugal and Finland underground waters. J Radioanal Nucl Chem 2017. [DOI: 10.1007/s10967-017-5166-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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9
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Measurement of radon in air using a radon-218Po calibration curve determined by an absorptive non-volatile liquid scintillator. RADIAT MEAS 2016. [DOI: 10.1016/j.radmeas.2016.10.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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10
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Stojković I, Todorović N, Nikolov J, Tenjović B. PSA discriminator influence on (222)Rn efficiency detection in waters by liquid scintillation counting. Appl Radiat Isot 2016; 112:80-8. [PMID: 27016710 DOI: 10.1016/j.apradiso.2016.03.020] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2015] [Revised: 02/18/2016] [Accepted: 03/17/2016] [Indexed: 11/15/2022]
Abstract
A procedure for the (222)Rn determination in aqueous samples using liquid scintillation counting (LSC) was evaluated and optimized. Measurements were performed by ultra-low background spectrometer Quantulus 1220™ equipped with PSA (Pulse Shape Analysis) circuit which discriminates alpha/beta spectra. Since calibration procedure is carried out with (226)Ra standard, which has both alpha and beta progenies, it is clear that PSA discriminator has vital importance in order to provide precise spectra separation. Improvement of calibration procedure was done through investigation of PSA discriminator level and, consequentially, the activity of (226)Ra calibration standard influence on (222)Rn efficiency detection. Quench effects on generated spectra i.e. determination of radon efficiency detection were also investigated with quench calibration curve obtained. Radon determination in waters based on modified procedure according to the activity of (226)Ra standard used, dependent on PSA setup, was evaluated with prepared (226)Ra solution samples and drinking water samples with assessment of measurement uncertainty variation included.
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Affiliation(s)
- Ivana Stojković
- University of Novi Sad, Faculty of Technical Sciences, Novi Sad, Serbia
| | - Nataša Todorović
- University of Novi Sad, Faculty of Sciences, Department of Physics, Novi Sad, Serbia
| | - Jovana Nikolov
- University of Novi Sad, Faculty of Sciences, Department of Physics, Novi Sad, Serbia
| | - Branislava Tenjović
- University of Novi Sad, Faculty of Sciences, Department of Chemistry, Novi Sad, Serbia
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11
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Fonollosa E, Peñalver A, Borrull F, Aguilar C. Radon in spring waters in the south of Catalonia. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2016; 151 Pt 1:275-281. [PMID: 26551586 DOI: 10.1016/j.jenvrad.2015.10.019] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2015] [Revised: 09/22/2015] [Accepted: 10/20/2015] [Indexed: 06/05/2023]
Abstract
Spring waters in the south of Catalonia were analysed to determine the (222)Rn activity in order to be able to establish a correlation between the obtained values with the geology of the area of origin of these samples, and also estimate the potential health risks associated with (222)Rn. Most of the analysed samples (90%) show (222)Rn activities lower than 100Bq/L (exposure limit in water recommended by the World Health Organisation and EU directive 2013/51/EURATOM). However, in some cases, the activity values found for this isotope exceeded those levels and this can be attributed to the geology of the area where the spring waters are located, which is predominantly of granitic characteristics. To verify the origin of the radon present in the analysed samples, the obtained activity values were compared with the activities of its parents ((226)Ra, (238)U and (234)U). Finally, we have calculated the annual effective dose from all the radionuclides measured in spring water samples. The results showed that the higher contribution due to spring water ingestion come from (222)Rn and (226)Ra. The resulting contribution to the annual effective dose due to radon ingestion varies between 10.2 and 765.8 μSv/y, and the total annual effective dose due to his parents, (226)Ra, (234)U and (238)U varies between 0.8 and 21.2 μSv/y so the consumption of these waters does not involve any risks to population due to its natural radioactivity content.
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Affiliation(s)
- E Fonollosa
- Departament de Química Analítica i Química Orgànica, Universitat Rovira i Virgili, Unitat de, Radioquímica Ambiental i Sanitaria (URAIS), Consorci d'Aigües de Tarragona (CAT), Carretera Nacional, 340. Km 1094, 43895 L'Ampolla, Tarragona, Spain
| | - A Peñalver
- Departament de Química Analítica i Química Orgànica, Universitat Rovira i Virgili, Unitat de, Radioquímica Ambiental i Sanitaria (URAIS), Consorci d'Aigües de Tarragona (CAT), Carretera Nacional, 340. Km 1094, 43895 L'Ampolla, Tarragona, Spain
| | - F Borrull
- Departament de Química Analítica i Química Orgànica, Universitat Rovira i Virgili, Unitat de, Radioquímica Ambiental i Sanitaria (URAIS), Consorci d'Aigües de Tarragona (CAT), Carretera Nacional, 340. Km 1094, 43895 L'Ampolla, Tarragona, Spain.
| | - C Aguilar
- Departament de Química Analítica i Química Orgànica, Universitat Rovira i Virgili, Unitat de, Radioquímica Ambiental i Sanitaria (URAIS), Consorci d'Aigües de Tarragona (CAT), Carretera Nacional, 340. Km 1094, 43895 L'Ampolla, Tarragona, Spain
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12
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Jobbágy V, Merešová J, Wätjen U. Critical remarks on gross alpha/beta activity analysis in drinking waters: conclusions from a European interlaboratory comparison. Appl Radiat Isot 2013; 87:429-34. [PMID: 24355306 DOI: 10.1016/j.apradiso.2013.11.073] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2013] [Accepted: 11/17/2013] [Indexed: 10/25/2022]
Abstract
The most common gross alpha/beta standard methods used for drinking water analysis are discussed, and sources of interferences are reviewed from a metrological point of view. Our study reveals serious drawbacks of gross methods on the basis of an interlaboratory comparison analyzing commercial mineral water samples with the participation of 71 laboratories. A proposal is made to obtain comparable measurement results using true standardized methods.
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Affiliation(s)
- V Jobbágy
- European Commission, Joint Research Centre, Institute for Reference Materials and Measurements, Retieseweg 111, B-2440 Geel, Belgium.
| | - J Merešová
- European Commission, Joint Research Centre, Institute for Reference Materials and Measurements, Retieseweg 111, B-2440 Geel, Belgium
| | - U Wätjen
- European Commission, Joint Research Centre, Institute for Reference Materials and Measurements, Retieseweg 111, B-2440 Geel, Belgium
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13
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Current status of gross alpha/beta activity analysis in water samples: a short overview of methods. J Radioanal Nucl Chem 2010. [DOI: 10.1007/s10967-010-0709-z] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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