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Magre A, Boulet B, Isnard H, Mialle S, Evrard O, Pourcelot L. Innovative ICP-MS/MS Method To Determine the 135Cs/ 137Cs Ratio in Low Activity Environmental Samples. Anal Chem 2023; 95:6923-6930. [PMID: 37071760 DOI: 10.1021/acs.analchem.3c00207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/20/2023]
Abstract
The 135Cs/137Cs isotopic ratio is a powerful tool for tracing the origin of radioactive contamination. Since the Fukushima accident, this ratio has been measured by mass spectrometry in several highly contaminated environmental matrices mainly collected near nuclear accident exclusion zones and former nuclear test areas. However, few data were reported at 137Cs environmental levels (<1 kBq kg-1). This is explained by the occurrence of analytical challenges related to the very low radiocesium content at the environmental level with the large presence of mass interferences, making 135Cs and 137Cs measurements difficult. To overcome these difficulties, a highly selective procedure for Cs extraction/separation combined with an efficient mass spectrometry measurement must be applied on a quantity of ca. 100 g of soil. In the current research, an innovative inductively coupled plasma-tandem mass spectrometry (ICP-MS/MS) method has been developed for the 135Cs/137Cs ratio measurement in low activity environmental samples. The use of ICP-MS/MS led to a powerful suppression of 135Cs and 137Cs interferences by introducing N2O, He, and, for the first time, NH3, into the collision-reaction cell. By adjusting the flow rates of these gases, the best compromise between a maximum signal in Cs and an effective interference elimination was achieved allowing a high Cs sensitivity of more than 1.105 cps/(ng g-1) and low background levels at m/z 135 and 137 lower than 0.6 cps. The accuracy of the developed method was successfully verified by analyzing two certified reference materials (IAEA-330 and IAEA-375) commonly used in the literature as validation samples and three sediment samples collected in the Niida River catchment (Japan) impacted by the Fukushima fallout.
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Affiliation(s)
- Anaelle Magre
- Laboratoire de métrologie de la radioactivité dans l'environnement (PSE-ENV/SAME/LMRE), IRSN, 91400 Orsay, France
- Laboratoire des Sciences du Climat et de l'Environnement (CNRS, CEA, UVSQ-IPSL), Université Paris-Saclay, 91191 Gif-sur-Yvette, France
| | - Beatrice Boulet
- Laboratoire de métrologie de la radioactivité dans l'environnement (PSE-ENV/SAME/LMRE), IRSN, 91400 Orsay, France
| | - Helene Isnard
- DES - Service d'Etudes Analytiques et de Réactivité des Surfaces (SEARS), CEA, Université Paris-Saclay, F-91191 Gif-Sur-Yvette, France
| | - Sebastien Mialle
- DES - Service d'Etudes Analytiques et de Réactivité des Surfaces (SEARS), CEA, Université Paris-Saclay, F-91191 Gif-Sur-Yvette, France
| | - Olivier Evrard
- Laboratoire des Sciences du Climat et de l'Environnement (CNRS, CEA, UVSQ-IPSL), Université Paris-Saclay, 91191 Gif-sur-Yvette, France
| | - Laurent Pourcelot
- Laboratoire d'étude et d'expertise sur la radioactivité de l'environnement (PSE-ENV/SEREN/LEREN), IRSN, 13108 Saint-Paul-lez-Durance, France
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Ohkubo T, Takei A, Tachi Y, Fukatsu Y, Deguchi K, Ohki S, Shimizu T. New Approach To Understanding the Experimental 133Cs NMR Chemical Shift of Clay Minerals via Machine Learning and DFT-GIPAW Calculations. J Phys Chem A 2023; 127:973-986. [PMID: 36657157 DOI: 10.1021/acs.jpca.2c08880] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Structural determination of adsorbed atoms on layered structures such as clay minerals is a complex subject. Radioactive cesium (Cs) is an important element for environmental conservation, so it is vital to understand its adsorption structure on clay. The nuclear magnetic resonance (NMR) parameters of 133Cs, which can be determined from solid-state NMR experiments, are sensitive to the local neighboring structures of adsorbed Cs. However, determining the Cs positions from NMR data alone is difficult. This paper describes an approach for identifying the expected atomic positions on clay minerals by combining machine learning (ML) with experimentally observed chemical shifts. A linear ridge regression model for ML is constructed from the smooth overlap of atomic position descriptor and gauge-including projector augmented wave (GIPAW) ab initio data. The constructed ML model predicts the GIPAW data to within a 3 ppm root-mean-squared error. At this stage, the 133Cs chemical shifts can be instantaneously calculated from the Cs positions on any clay layers using ML. The inverse analysis, which derives the atomic positions from experimentally observed chemical shifts, is developed from the ML model. The input data for the inverse analysis are the layer structure and the experimentally observed chemical shifts. The Cs positions for the targeted chemical shifts are then output. Inverse analysis is applied to montmorillonite, and the resultant Cs positions are found to be consistent with previous results (Ohkubo, T.; et al. J. Phys. Chem. A 2018, 122, 9326-9337). The Cs positions on saponite clay are also clarified from experimentally observed chemical shifts and inverse analysis.
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Affiliation(s)
- Takahiro Ohkubo
- Graduate School of Engineering, Chiba University, 1-33 Yayoi-cho Inage-ku, Chiba 263-8522, Japan
| | - Akihiro Takei
- Graduate School of Engineering, Chiba University, 1-33 Yayoi-cho Inage-ku, Chiba 263-8522, Japan
| | - Yukio Tachi
- Japan Atomic Energy Agency, Muramatsu 4-33, Tokai, Ibaraki 319-1194, Japan
| | - Yuta Fukatsu
- Japan Atomic Energy Agency, Muramatsu 4-33, Tokai, Ibaraki 319-1194, Japan
| | - Kenzo Deguchi
- High Field NMR Group, National Institute for Materials Science (NIMS), 3-13 Sakura, Tsukuba, Ibaraki 305-0003, Japan
| | - Shinobu Ohki
- High Field NMR Group, National Institute for Materials Science (NIMS), 3-13 Sakura, Tsukuba, Ibaraki 305-0003, Japan
| | - Tadashi Shimizu
- High Field NMR Group, National Institute for Materials Science (NIMS), 3-13 Sakura, Tsukuba, Ibaraki 305-0003, Japan
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3
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Long-term variation of 90Sr and 137Cs in environmental and food samples around Qinshan nuclear power plant, China. Sci Rep 2021; 11:20903. [PMID: 34686687 PMCID: PMC8536726 DOI: 10.1038/s41598-021-00114-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Accepted: 10/05/2021] [Indexed: 11/09/2022] Open
Abstract
Environmental radioactivity monitoring in the surroundings of nuclear facilities is important to provide baseline data for effective detection in case of any radioactive release in the region. In this work, we report for the first time the long-term monitoring data of 137Cs and 90Sr in environmental and food samples around Qinshan nuclear power plant in 2012–2019. The distribution levels, temporal variations and source terms of 137Cs and 90Sr in the investigated samples were discussed. The annual effective dose (AED) for the local population from the ingestion of foods was also evaluated. Peak values of 90Sr and 137Cs concentrations and 137Cs/90Sr activity ratio were observed in total atmospheric deposition in 2016 and some water and food samples in the following years. This seems to be associated to an additional radioactive input, mostly likely from the operational release of a local facility. This demonstrates that 90Sr and 137Cs, especially the 137Cs/90Sr activity ratio, are sensitive indicators for detecting potential radioactive releases. Nevertheless, overall 90Sr and 137Cs activity concentrations measured during 2012–2019 in this work were at the background levels with average AED far below the internationally permissible limit and recommendation.
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Tokonami S, Miura T, Akata N, Tazoe H, Hosoda M, Chutima K, Kudo H, Ogura K, Fujishima Y, Tamakuma Y, Shimizu M, Kikuchi K, Kashiwakura I. Support activities in Namie Town, Fukushima undertaken by Hirosaki University. Ann ICRP 2021; 50:102-108. [PMID: 34092120 DOI: 10.1177/01466453211006806] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
This paper does not necessarily reflect the views of the International Commission on Radiological Protection.Several radiation monitoring research projects are underway on dose assessment, biological analysis, and risk communication under an agreement with Namie Town. Indoor radon and thoron progeny concentrations have been measured using passive-type monitors to estimate internal doses due to inhalation. In addition, airborne radiocaesium concentrations at five points in Namie Town have been analysed using a high-purity germanium detector to estimate internal doses for comparison with radon. External radiation doses from natural and artificial radionuclides have also been estimated using an in-situ gamma-ray spectrometer. Other support activities are mentioned briefly in this article.
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Affiliation(s)
- Shinji Tokonami
- Institute of Radiation Emergency Medicine, Hirosaki University, 66-1 Hon-cho, Hirosaki, Aomori 036-8564, Japan; e-mail:
| | - Tomisato Miura
- Institute of Radiation Emergency Medicine, Hirosaki University, 66-1 Hon-cho, Hirosaki, Aomori 036-8564, Japan; e-mail:
| | - Naofumi Akata
- Institute of Radiation Emergency Medicine, Hirosaki University, 66-1 Hon-cho, Hirosaki, Aomori 036-8564, Japan; e-mail:
| | - Hirofumi Tazoe
- Institute of Radiation Emergency Medicine, Hirosaki University, 66-1 Hon-cho, Hirosaki, Aomori 036-8564, Japan; e-mail:
| | - Masahiro Hosoda
- Institute of Radiation Emergency Medicine, Hirosaki University, 66-1 Hon-cho, Hirosaki, Aomori 036-8564, Japan; e-mail: .,Hirosaki University Graduate School of Health Sciences, Japan
| | - Kranrod Chutima
- Institute of Radiation Emergency Medicine, Hirosaki University, 66-1 Hon-cho, Hirosaki, Aomori 036-8564, Japan; e-mail:
| | - Hiromi Kudo
- Hirosaki University Graduate School of Health Sciences, Japan
| | - Koya Ogura
- Hirosaki University Graduate School of Health Sciences, Japan
| | - Yohei Fujishima
- Institute of Radiation Emergency Medicine, Hirosaki University, 66-1 Hon-cho, Hirosaki, Aomori 036-8564, Japan; e-mail:
| | - Yuki Tamakuma
- Institute of Radiation Emergency Medicine, Hirosaki University, 66-1 Hon-cho, Hirosaki, Aomori 036-8564, Japan; e-mail:
| | - Mayumi Shimizu
- Institute of Radiation Emergency Medicine, Hirosaki University, 66-1 Hon-cho, Hirosaki, Aomori 036-8564, Japan; e-mail:
| | - Kazutaka Kikuchi
- Institute of Radiation Emergency Medicine, Hirosaki University, 66-1 Hon-cho, Hirosaki, Aomori 036-8564, Japan; e-mail:
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Zok D, Blenke T, Reinhard S, Sprott S, Kegler F, Syrbe L, Querfeld R, Takagai Y, Drozdov V, Chyzhevskyi I, Kirieiev S, Schmidt B, Adlassnig W, Wallner G, Dubchak S, Steinhauser G. Determination of Characteristic vs Anomalous 135Cs/ 137Cs Isotopic Ratios in Radioactively Contaminated Environmental Samples. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:4984-4991. [PMID: 33709694 DOI: 10.1021/acs.est.1c00180] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
A contamination with the ubiquitous radioactive fission product 137Cs cannot be assigned per se to its source. We used environmental samples with varying contamination levels from various parts of the world to establish their characteristic 135Cs/137Cs isotope ratios and thereby allow their distinction. The samples included biological materials from Chernobyl and Fukushima, historic ashed human lung tissue from the 1960s from Austria, and trinitite from the Trinity Test Site, USA. After chemical separation and gas reaction shifts inside a triple quadrupole ICP mass spectrometer, characteristic 135Cs/137Cs isotope signatures (all as per March 11, 2011) were obtained for Fukushima- (∼0.35) and Chernobyl-derived (∼0.50) contaminations, in agreement with the literature for these contamination sources. Both signatures clearly distinguish from the characteristic high ratio (1.9 ± 0.2) for nuclear-weapon-produced radiocesium found in human lung tissue. Trinitite samples exhibited an unexpected, anomalous pattern by displaying a low (<0.4) and nonuniform 135Cs/137Cs ratio. This exemplifies a 137Cs-rich fractionation of the plume in a nuclear explosion, where 137Cs is a predominant species in the fireball. The onset of 135Cs was delayed because of the longer half-life of its parent nuclide 135Xe, causing a spatial separation of gaseous 135Xe from condensed 137Cs, which is the reason for the atypical 135Cs/137Cs fractionation in the fallout at the test site.
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Affiliation(s)
- Dorian Zok
- Leibniz Universität Hannover, Institute of Radioecology and Radiation Protection, 30419 Hannover, Germany
| | - Tobias Blenke
- Leibniz Universität Hannover, Institute of Radioecology and Radiation Protection, 30419 Hannover, Germany
| | - Sandra Reinhard
- Leibniz Universität Hannover, Institute of Radioecology and Radiation Protection, 30419 Hannover, Germany
| | - Sascha Sprott
- Leibniz Universität Hannover, Institute of Radioecology and Radiation Protection, 30419 Hannover, Germany
| | - Felix Kegler
- Leibniz Universität Hannover, Institute of Radioecology and Radiation Protection, 30419 Hannover, Germany
| | - Luisa Syrbe
- Leibniz Universität Hannover, Institute of Radioecology and Radiation Protection, 30419 Hannover, Germany
| | - Rebecca Querfeld
- Leibniz Universität Hannover, Institute of Radioecology and Radiation Protection, 30419 Hannover, Germany
| | - Yoshitaka Takagai
- Fukushima University, Faculty of Symbiotic Systems Science, Fukushima 960-1296, Japan
| | - Vladyslav Drozdov
- State Specialized Enterprise "Ecocentre" (SSE "Ecocentre"), Chernobyl 07270, Ukraine
| | - Ihor Chyzhevskyi
- State Specialized Enterprise "Ecocentre" (SSE "Ecocentre"), Chernobyl 07270, Ukraine
| | - Serhii Kirieiev
- State Specialized Enterprise "Ecocentre" (SSE "Ecocentre"), Chernobyl 07270, Ukraine
| | - Brigitte Schmidt
- University of Vienna, Faculty of Life Sciences, Cell Imaging and Ultrastructure Research, 1090 Vienna, Austria
| | - Wolfram Adlassnig
- University of Vienna, Faculty of Life Sciences, Cell Imaging and Ultrastructure Research, 1090 Vienna, Austria
| | - Gabriele Wallner
- University of Vienna, Faculty of Chemistry, Institute of Inorganic Chemistry, 1090 Vienna, Austria
| | - Sergiy Dubchak
- State Specialized Enterprise "Radon Association", Kyiv 03083, Ukraine
| | - Georg Steinhauser
- Leibniz Universität Hannover, Institute of Radioecology and Radiation Protection, 30419 Hannover, Germany
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Wai KM, Krstic D, Nikezic D, Lin TH, Yu PKN. External Cesium-137 doses to humans from soil influenced by the Fukushima and Chernobyl nuclear power plants accidents: a comparative study. Sci Rep 2020; 10:7902. [PMID: 32404910 PMCID: PMC7220933 DOI: 10.1038/s41598-020-64812-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Accepted: 04/21/2020] [Indexed: 11/24/2022] Open
Abstract
External exposure to gamma-photon irradiation from soil contamination due to nuclear power plant (NPP) accidents has significant contribution to human radiation exposure in the proximity of the NPP. Detailed absorbed doses in human organs are rarely reported in the literature. We applied the Monte Carlo Neutron Particle (MCNP) transport code to calculate and compare the absorbed doses in different human organs. The absorbed doses by gamma-photon radiation were from cesium-137 (137Cs) in soil contaminated by the two major NPP accidents. More serious and wide-spread impacts of the Chernobyl NPP accident on soil contamination in Ukraine, Belarus, Russia and countries as far as Sweden and Greece were due to the inland location, radiative plume transport pathway and high 137Cs emission strength (9 times the Fukushima emission). Based on our MCNP calculations, the largest absorbed dose was found in skin. The maximum calculated external 137Cs annual effective dose received from the Chernobyl accident was 10 times higher relative to the Fukushima accident. Our calculated effective doses at various influenced areas were comparable to those available in the literature. The calculated annual effective doses at areas near the Fukushima and Chernobyl NPPs exceeded the ICRP recommendation of 1 mSv yr-1.
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Affiliation(s)
- Ka-Ming Wai
- Department of Civil and Environmental Engineering, College of Engineering, Shantou University, Shantou, China.
- Intelligent Manufacturing Key Laboratory of Ministry of Education, Shantou University, Shantou, China.
| | - Dragana Krstic
- Faculty of Science, University of Kragujevac, R. Domanovica 12, Kragujevac, 34000, Serbia
| | - Dragoslav Nikezic
- Faculty of Science, University of Kragujevac, R. Domanovica 12, Kragujevac, 34000, Serbia
| | - Tang-Huang Lin
- Center for Space and Remote Sensing Research, National Central University, Taoyuan City, Taiwan
| | - Peter K N Yu
- Department of Physics, City University of Hong Kong, Hong Kong SAR, China.
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Zhu L, Xu C, Hou X, Qiao J, Zhao Y, Liu G. Determination of Ultratrace Level 135Cs and 135Cs/ 137Cs Ratio in Small Volume Seawater by Chemical Separation and Thermal Ionization Mass Spectrometry. Anal Chem 2020; 92:6709-6718. [PMID: 32270673 DOI: 10.1021/acs.analchem.0c00688] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The atomic ratio of 135Cs/137Cs is a powerful fingerprint for distinguishing the source terms of radioactive contamination and tracing the circulation of water masses in the ocean. However, the determination of the 135Cs/137Cs ratio is very difficult due to the ultratrace level of 135Cs (<0.02 mBq/m3) and 137Cs (<2 Bq/m3) in the ordinary seawater samples. In this work, a sensitive method was developed for determination of 135Cs concentration and 135Cs/137Cs ratio in seawater using chemical separation combined with thermal ionization mass spectrometry (TIMS) measurement. Cesium was first preconcentrated from seawater using ammonium molybdophosphate-polyacrylonitrile column chromatography and then purified using cation exchange chromatography to remove the interferences. With this method, decontamination factors of 6.0 × 106 for barium and 1800 for rubidium and a chemical yield of more than 60% for cesium were achieved. By using glucose as an activator, the ionization efficiency of cesium was significantly improved to 50.6%, and a constant high current of Cs+ (20 V) can be maintained for more than 180 min, which ensures sensitive and reliable measurement of low level 135Cs and 137Cs. Detection limits of 4.0 × 10-17 g/L for both 135Cs and 137Cs for 200 mL seawater were achieved, which enables the accurate determination of 135Cs concentration and 135Cs/137Cs ratio in a small volume of seawater samples (<200 mL). The developed method has been validated by analysis of seawater reference material IAEA-443. Seawater samples collected from the Greenland Sea, Baltic Sea, and Danish Straits have been successfully analyzed for 135Cs concentrations and 135Cs/137Cs ratios, and the results showed that 135Cs concentrations in the seawater of the Baltic Sea is much higher than that in the Greenland Sea, which is attributed to the high deposition of Chernobyl accident derived radiocesium in the Baltic Sea region.
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Affiliation(s)
- Liuchao Zhu
- Technical University of Denmark, Department of Environmental Engineering, Risø Campus, Roskilde DK-4000, Denmark
| | - Changkun Xu
- China Institute of Atomic Energy, Beijing 102413, China
| | - Xiaolin Hou
- Technical University of Denmark, Department of Environmental Engineering, Risø Campus, Roskilde DK-4000, Denmark
| | - Jixin Qiao
- Technical University of Denmark, Department of Environmental Engineering, Risø Campus, Roskilde DK-4000, Denmark
| | - Yonggang Zhao
- China Institute of Atomic Energy, Beijing 102413, China
| | - Guorong Liu
- China Institute of Atomic Energy, Beijing 102413, China
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8
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Isotopic ratios of uranium and caesium in spherical radioactive caesium-bearing microparticles derived from the Fukushima Dai-ichi Nuclear Power Plant. Sci Rep 2020; 10:3281. [PMID: 32094430 PMCID: PMC7039901 DOI: 10.1038/s41598-020-59933-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Accepted: 02/04/2020] [Indexed: 11/08/2022] Open
Abstract
Spherical radioactive caesium (Cs)-bearing microparticles (CsMPs) were emitted during the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident in March, 2011. The emission source (timing) and formation process of these particles remain unclear. In this study, the isotopic ratios of uranium (235U and 238U) and caesium (133Cs, 134Cs, 135Cs, and 137Cs) isotopes in the five spherical CsMPs (ca. 2 μm in size) sampled at 50 km west of the FDNPP were determined using secondary ion mass spectrometry and laser ablation-ICPMS, respectively. Results showed that the 235U/238U ratios of CsMPs were homogeneous (1.93 ± 0.03, N = 4) and close to those estimated for the fuel cores in units 2 and 3, and that the Cs isotopic ratios of CsMP were identical to those of units 2 and 3. These results indicated that U and Cs in the spherical CsMPs originated exclusively from the fuel melt in the reactors. Based on a thorough review of literatures related to the detailed atmospheric releases of radionuclides, the flow of plumes from the FDNPP reactor units during the accident and the U and Cs isotopic ratio results in this study, we hereby suggest that the spherical CsMPs originate only from the fuel in unit 2 on the night of 14 March to the morning of 15 March. The variation range of the analysed 235U/238U isotopic ratios for the four spherical particles was extremely narrow. Thus, U may have been homogenised in the source through the formation of fuel melt, which ultimately evaporating and taken into CsMPs in the reactor and was released from the unit 2.
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Cwanek A, Mietelski JW, Łokas E, Olech MA, Anczkiewicz R, Misiak R. Sources and variation of isotopic ratio of airborne radionuclides in Western Arctic lichens and mosses. CHEMOSPHERE 2020; 239:124783. [PMID: 31726517 DOI: 10.1016/j.chemosphere.2019.124783] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Revised: 08/24/2019] [Accepted: 09/04/2019] [Indexed: 06/10/2023]
Abstract
This research concerned radioactivity of lichens and mosses from coastal zones of the Canadian Arctic and Alaska. Over 50 samples were collected from 7 positions during two scientific expeditions in 2012 and 2013. The tundra contamination caused by anthropogenic radionuclides was relatively low, reaching mean values with SD's of: 17.4 ± 3.5 Bq/kg for 90Sr, 14.0 ± 2.9 Bq/kg for 134Cs, 38.4 ± 7.5 Bq/kg for 137Cs, 0.86 ± 0.24 Bq/kg for 239+240Pu, 0.065 ± 0.017 Bq/kg for 238Pu and 0.50 ± 0.13 Bq/kg for 241Am. The increase of activity concentration with increasing latitudes was noticed mostly in regard to 90Sr, Pu isotopes and 241Am. The analysis of isotopic ratios exhibited dominant contribution of the global fallout (+SNAP 9A satellite re-entry fallout) for the presence of plutonium isotopes and 241Am. The Fukushima fallout signature was identified in a few lichens from Alaska. However, the influence of additional unknown factor on the occurrence of 90Sr and 137Cs has been detected in western part of Canadian Arctic. Natural radioisotopes of thorium and uranium were found throughout the entire investigated region and the average values of activity concentration with SD's were as follows: 2.92 ± 0.47 Bq/kg for 230Th, 2.61 ± 0.48 Bq/kg for 232Th, 4.32 ± 0.80 Bq/kg for 234U and 3.97 ± 0.71 Bq/kg for 238U. Examined Western Arctic tundra was not affected with any technically enhanced natural radioactivity.
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Affiliation(s)
- Anna Cwanek
- Institute of Nuclear Physics, Polish Academy of Sciences, Radzikowskiego 152, 31-342, Krakow, Poland.
| | - Jerzy W Mietelski
- Institute of Nuclear Physics, Polish Academy of Sciences, Radzikowskiego 152, 31-342, Krakow, Poland
| | - Edyta Łokas
- Institute of Nuclear Physics, Polish Academy of Sciences, Radzikowskiego 152, 31-342, Krakow, Poland
| | - Maria A Olech
- Institute of Botany, Jagiellonian University, Lubicz 46, 31-512, Krakow, Poland
| | - Robert Anczkiewicz
- Institute of Geological Sciences, Polish Academy of Sciences, Kraków Research Centre, Senacka 1, 31-002, Krakow, Poland
| | - Ryszard Misiak
- Institute of Nuclear Physics, Polish Academy of Sciences, Radzikowskiego 152, 31-342, Krakow, Poland
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10
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Rehman HU, Ju K, Kim Y. Photon and neutron hybrid transmutation for radioactive cesium and iodine. ANN NUCL ENERGY 2019. [DOI: 10.1016/j.anucene.2019.06.029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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11
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Okumura S, Ishikawa S. Theoretical study on the ability of bicyclic cryptands to separate alkali-metal isotopes by ion exchange. NEW J CHEM 2019. [DOI: 10.1039/c9nj02837d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Cryptand [2.2.2] collects heavier isotope 137Cs more readily than [3.2.2] that gives a potential minimum at d = de.
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Affiliation(s)
- Sayako Okumura
- Department of Chemistry
- School of Science
- Tokai University
- Hiratsuka 259-1292
- Japan
| | - Shigeru Ishikawa
- Department of Chemistry
- School of Science
- Tokai University
- Hiratsuka 259-1292
- Japan
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12
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Dunne JA, Martin PG, Yamashiki Y, Ang IXY, Scott TB, Richards DA. Spatial pattern of plutonium and radiocaesium contamination released during the Fukushima Daiichi nuclear power plant disaster. Sci Rep 2018; 8:16799. [PMID: 30429490 PMCID: PMC6235829 DOI: 10.1038/s41598-018-34302-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Accepted: 10/04/2018] [Indexed: 11/12/2022] Open
Abstract
Plutonium and radiocaesium are hazardous contaminants released by the Fukushima Daiichi nuclear power plant (FDNPP) disaster and their distribution in the environment requires careful characterisation using isotopic information. Comprehensive spatial survey of 134Cs and 137Cs has been conducted on a regular basis since the accident, but the dataset for 135Cs/137Cs atom ratios and trace isotopic analysis of Pu remains limited because of analytical challenges. We have developed a combined chemical procedure to separate Pu and Cs for isotopic analysis of environmental samples from contaminated catchments. Ultra-trace analyses reveal a FDNPP Pu signature in environmental samples, some from further afield than previously reported. For two samples, we attribute the dominant source of Pu to Reactor Unit 3. We review the mechanisms responsible for an emergent spatial pattern in 134,135Cs/137Cs in areas northwest (high 134Cs/137Cs, low 135Cs/137Cs) and southwest (low 134Cs/137Cs, high 135Cs/137Cs) of FDNPP. Several samples exhibit consistent 134,135Cs/137Cs values that are significantly different from those deposited on plant specimens collected in previous works. A complex spatial pattern of Pu and Cs isotopic signature is apparent. To confidently attribute the sources of mixed fallout material, future studies must focus on analysis of individual FDNPP-derived particles.
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Affiliation(s)
- James A Dunne
- School of Geographical Sciences, University of Bristol, University Road, Bristol, BS8 1SS, UK. .,Bristol Isotope Group, University of Bristol, Wills Memorial Building, Queen's Road, Bristol, BS8 1RJ, UK.
| | - Peter G Martin
- Interface Analysis Centre, HH Wills Physics Laboratory, University of Bristol, Bristol, BS8 1TL, UK
| | - Yosuke Yamashiki
- Graduate School of Advanced Integrated Studies in Human Survivability, Kyoto University, Kyoto, 606-8501, Japan
| | - Ian X Y Ang
- Interface Analysis Centre, HH Wills Physics Laboratory, University of Bristol, Bristol, BS8 1TL, UK
| | - Tom B Scott
- Interface Analysis Centre, HH Wills Physics Laboratory, University of Bristol, Bristol, BS8 1TL, UK
| | - David A Richards
- School of Geographical Sciences, University of Bristol, University Road, Bristol, BS8 1SS, UK. .,Bristol Isotope Group, University of Bristol, Wills Memorial Building, Queen's Road, Bristol, BS8 1RJ, UK.
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13
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14
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Yang G, Tazoe H, Yamada M. Can 129I track 135Cs, 236U, 239Pu, and 240Pu apart from 131I in soil samples from Fukushima Prefecture, Japan? Sci Rep 2017; 7:15369. [PMID: 29133826 PMCID: PMC5684215 DOI: 10.1038/s41598-017-15714-w] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Accepted: 10/31/2017] [Indexed: 12/03/2022] Open
Abstract
In the present study, 129I activities and 129I/127I atom ratios were measured in 60 soil samples contaminated by the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident. The 127I concentrations, 129I activities, and 129I/127I atom ratios in dry-weight were observed to be 0.121–23.6 mg kg−1, 0.962–275 mBq kg−1, and (0.215–79.3) × 10−7, respectively. The maximum values of both 129I activities and 129I/127I atom ratios in Japanese soil increased about three orders of magnitude due to this accident. The equation logy = 0.877logx + 0.173 (Pearson’s r = 0.936; x, 129I concentration; y, 131I concentration; decay-corrected to March 11, 2011) instead of a simple constant may be a better way to express the relationship between 129I and 131I in Japanese soil affected by both global fallout and FDNPP accident fallout. In addition, a moderate correlation was observed between 129I and 135Cs (logy = 0.624logx + 1.01, Pearson’s r = 0.627; x, 129I activity; y, 135Cs activity). However, 129I presented larger fractionations with less volatile radionuclides, such as 236U, 239Pu, and 240Pu. These findings indicated 135Cs could be roughly estimated from 129I or 131I; this is advantageous as fewer 135Cs data are available and 135Cs/137Cs is being considered a promising tracer during radiocesium source identification.
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Affiliation(s)
- Guosheng Yang
- Department of Radiation Chemistry, Institute of Radiation Emergency Medicine, Hirosaki University, 66-1 Hon-cho, Hirosaki, Aomori, 036-8564, Japan.,Division of Nuclear Technology and Applications, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, China.,Beijing Engineering Research Center of Radiographic Techniques and Equipment, Beijing, 100049, China
| | - Hirofumi Tazoe
- Department of Radiation Chemistry, Institute of Radiation Emergency Medicine, Hirosaki University, 66-1 Hon-cho, Hirosaki, Aomori, 036-8564, Japan
| | - Masatoshi Yamada
- Department of Radiation Chemistry, Institute of Radiation Emergency Medicine, Hirosaki University, 66-1 Hon-cho, Hirosaki, Aomori, 036-8564, Japan.
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15
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Dunne JA, Richards DA, Chen HW. Procedures for precise measurements of 135Cs/137Cs atom ratios in environmental samples at extreme dynamic ranges and ultra-trace levels by thermal ionization mass spectrometry. Talanta 2017; 174:347-356. [PMID: 28738591 DOI: 10.1016/j.talanta.2017.06.033] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2017] [Revised: 06/07/2017] [Accepted: 06/12/2017] [Indexed: 10/19/2022]
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16
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Isotopic compositions of 236U, 239Pu, and 240Pu in soil contaminated by the Fukushima Daiichi Nuclear Power Plant accident. Sci Rep 2017; 7:13619. [PMID: 29051607 PMCID: PMC5648813 DOI: 10.1038/s41598-017-13998-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2017] [Accepted: 10/04/2017] [Indexed: 11/18/2022] Open
Abstract
Six years after the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident, data for 236U and 236U/238U have remained limited to a few heavily contaminated samples. In the present study, activities of 236U, 239Pu, and 240Pu, along with other U isotopes in 46 soil samples both heavily and lightly contaminated by this accident were measured by inductively coupled plasma–mass spectrometry (ICP-MS) and triple-quadrupole ICP-MS. The 236U activities and 236U/238U atom ratios in these soil samples were in the range of (0.469–24.4) × 10−5 Bq kg−1 and ((0.099–1.35) × 10−7), respectively. Higher 240Pu/239Pu atom ratios (0.245–0.312) and 238Pu/239+240Pu activity ratios (0.859–1.62) indicated Pu contamination originated from this accident and global fallout in some samples. For those soil samples along with black substances collected along roads in Fukushima Prefecture, high linear correlations were presented between 236U activities and 239+240Pu activities (Pearson’s r = 0.755, p < 0.01), and between 236U activities and 238Pu activities (Pearson’s r = 0.844, p < 0.01). The analysis of these soil samples confirmed the release of 236U, although in trace amounts, during the FDNPP accident.
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17
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Zheng J, Cao L, Tagami K, Uchida S. Triple-Quadrupole Inductively Coupled Plasma-Mass Spectrometry with a High-Efficiency Sample Introduction System for Ultratrace Determination of 135Cs and 137Cs in Environmental Samples at Femtogram Levels. Anal Chem 2016; 88:8772-9. [DOI: 10.1021/acs.analchem.6b02150] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Jian Zheng
- Biospheric Assessment for Waste Disposal Team & Fukushima Project Headquarters, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology Anagawa 4-9-1, Inage, Chiba 263-8555, Japan
| | - Liguo Cao
- Biospheric Assessment for Waste Disposal Team & Fukushima Project Headquarters, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology Anagawa 4-9-1, Inage, Chiba 263-8555, Japan
- School
of Geographic and Oceanographic Sciences, Nanjing University, Nanjing 210023, China
| | - Keiko Tagami
- Biospheric Assessment for Waste Disposal Team & Fukushima Project Headquarters, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology Anagawa 4-9-1, Inage, Chiba 263-8555, Japan
| | - Shigeo Uchida
- Biospheric Assessment for Waste Disposal Team & Fukushima Project Headquarters, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology Anagawa 4-9-1, Inage, Chiba 263-8555, Japan
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