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Dutheil P, Paatero J, Rodushkin I, Sundström T, Leppänen AP, Salminen-Paatero S. 137Cs and isotopic ratios of Pu and U in lichens and mosses from Russian Arctic areas. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:76769-76783. [PMID: 37247140 PMCID: PMC10299934 DOI: 10.1007/s11356-023-27795-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2023] [Accepted: 05/16/2023] [Indexed: 05/30/2023]
Abstract
Knowledge of past anthropogenic sources of radionuclide contamination in Russian Arctic areas is important to assess the radioecological situation of these less-studied regions. Therefore, we investigated the sources of radionuclide contamination in Russian Arctic in the 1990s. Lichen and moss samples were collected from 1993 to 1996 in Kola Peninsula, Franz Josef Land, and few other locations. The activity concentration of 137Cs was determined from the archived samples by gamma spectrometry in 2020. After radiochemical separation of Pu and U isotopes from the lichens and mosses, mass ratios 240Pu/239Pu, 234U/238U, 235U/238U, and 236U/238U were determined by mass spectrometry. 137Cs activity concentrations at the sampling date were found to vary from 3.1 ± 1.4 (Inari, Finnish-Russian border) to 303 ± 7 (Kola Peninsula) Bq/kg. The ranges of isotopic ratios were 0.0592 ± 0.0007 to 0.253 ± 0.082 for 240Pu/239Pu, (4.89 ± 3.91) × 10-5 to (6.86 ± 0.04) × 10-5 for 234U/238U, 0.0072104(21) to 0.007376(41) for 235U/238U, and from below 1 × 10-7 to (2.65 ± 0.19) × 10-6 for 236U/238U, respectively. Based on the measured isotopic ratios and characteristic isotopic ratios of known contamination sources, the main Pu and U sources in the sampled lichens and mosses are global fallout, the Chernobyl accident, and possibly local nuclear activities. These results contribute to further understanding of past nuclear events and resulting nuclear contamination in Russian Arctic terrestrial areas.
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Affiliation(s)
- Paul Dutheil
- Department of Chemistry, P.O. Box 55, FI-00014, University of Helsinki, Finland
- Department of Radiation Safety and Security, Paul Scherrer Institute, Forschungsstrasse 111, CH-5232, Villigen PSI, Switzerland
| | - Jussi Paatero
- Finnish Meteorological Institute, P.O. Box 503, Helsinki, Finland
| | | | - Timo Sundström
- Department of Chemistry, P.O. Box 55, FI-00014, University of Helsinki, Finland
| | - Ari-Pekka Leppänen
- Radiation and Nuclear Safety Authority-STUK, Lähteentie 2, 96460, Rovaniemi, Finland
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Wallner G, Uguz H, Kern M, Jirsa F, Hain K. Retrospective determination of fallout radionuclides and 236U/ 238U, 233U/ 236U and 240Pu/ 239Pu atom ratios on air filters from Vienna and Salzburg, Austria. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2022; 255:107030. [PMID: 36191507 DOI: 10.1016/j.jenvrad.2022.107030] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Revised: 07/21/2022] [Accepted: 07/23/2022] [Indexed: 06/16/2023]
Abstract
137Cs and 241Pu (via 241Am) concentrations were measured γ-spectrometrically on air filters from the early 1960s (mainly from 1964-66) from Vienna, Austria, and an alpine station in Salzburg, Austria. Accelerator mass spectrometry (AMS) was used to determine 240Pu/239Pu, 236U/238U and 233U/236U atom ratios as well as 236U, 239Pu and 240Pu atom concentrations. The maximum 236U/238U atom ratio of these unique undisturbed global fallout samples was (1.19 ± 0.31) × 10-5 in spring 1964. The 233U/236U atom ratios were found within (0.15-0.49) × 10-2 and indicate that the weapons tests of the early 1960s can be excluded as 233U source. The 236U/239Pu atom ratios were calculated in the range of 0.22-0.48.
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Affiliation(s)
- G Wallner
- Faculty of Chemistry, Institute of Inorganic Chemistry, University of Vienna, Währingerstr. 42, A-1090, Vienna, Austria.
| | - H Uguz
- Faculty of Chemistry, Institute of Inorganic Chemistry, University of Vienna, Währingerstr. 42, A-1090, Vienna, Austria
| | - M Kern
- Faculty of Physics, Isotope Physics, University of Vienna, Währingerstr. 17, A-1090, Vienna, Austria
| | - F Jirsa
- Faculty of Chemistry, Institute of Inorganic Chemistry, University of Vienna, Währingerstr. 42, A-1090, Vienna, Austria; University of Johannesburg, Department of Zoology, Auckland Park, 2006, South Africa
| | - K Hain
- Faculty of Physics, Isotope Physics, University of Vienna, Währingerstr. 17, A-1090, Vienna, Austria
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3
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Shao Y, Zhang J, Luo M, Xu D, Ma L. A review of anthropogenic radionuclide 236U: Environmental application and analytical advances. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2022; 251-252:106944. [PMID: 35696882 DOI: 10.1016/j.jenvrad.2022.106944] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Accepted: 06/05/2022] [Indexed: 06/15/2023]
Abstract
236U is an anthropogenic radionuclide that is produced from nuclear reactions of 235U(n, γ) and 238U(n, 3n). It has gained extensive attention in the field of environment, geology, nuclear emergency, and nuclear forensics. Due to the unique physical and chemical character and the distinct fingerprint character from different sources, 236U has been successfully applied in the environmental tracer, nuclear material source appointment, and environmental assessment. Until now, few reviews were published about the database, application, and the latest analytical technology development of 236U. In this review, the 236U concentration and 236U/238U isotope ratio were summarized, and the data were classified into four categories, including soil and seawater samples affected by global fallout and nuclear incidents. Furthermore, the development of environmental application and pretreatment methods were also summarized. The advanced pretreatment technology using alkali fusion and flow injection was especially discussed to introduce the development of a rapid analytical method. Finally, the research challenge and direction of 236U were proposed for further research, such as the tracer application combining 236U with other radionuclides in the terrestrial environment and the precise analysis of minor isotopes in ultra-trace uranium samples. We hope this review will help scholars to have a deep research on the analysis and application of 236U.
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Affiliation(s)
- Yang Shao
- Beijing Engineering Research Center of Radiographic Techniques and Equipment, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, 100049, China
| | - Jilong Zhang
- State Nuclear Security Technology Center, Beijing, 102401, China
| | - Min Luo
- Beijing Engineering Research Center of Radiographic Techniques and Equipment, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, 100049, China
| | - Diandou Xu
- Beijing Engineering Research Center of Radiographic Techniques and Equipment, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, 100049, China
| | - Lingling Ma
- Beijing Engineering Research Center of Radiographic Techniques and Equipment, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, 100049, China.
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4
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Wallner G, Zima P, Moser W, Uguz H, Bartmann MG, Steier P, Hain K. Retrospective determination of U and Pu isotopes and atom ratios in lung samples from Vienna, Austria. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2022; 251-252:106965. [PMID: 35843081 DOI: 10.1016/j.jenvrad.2022.106965] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Revised: 07/08/2022] [Accepted: 07/10/2022] [Indexed: 06/15/2023]
Abstract
Uranium and plutonium isotope concentrations as well as 236U/238U and 240Pu/239Pu atom ratios were measured by AMS in human lung samples from the early 1960s. The 236U concentrations as well as the 236U/238U atom ratios show a maximum in 1964, 239Pu and 240Pu concentrations are increasing continually from 1962 to 1965. 236U/238U atom ratios are lower by two orders of magnitude compared to corresponding aerosol data from Vienna, probably due to older 238U deposited in the lungs, enhanced 238U concentrations in the city air, and activity partition within different particle sizes. The 236U/239Pu atom ratios in lung samples are also lower than expected from the aerosol data, while 240Pu/239Pu atom ratios lie well within the range typical for nuclear bomb fallout.
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Affiliation(s)
- G Wallner
- Faculty of Chemistry, Institute of Inorganic Chemistry, University of Vienna, Währingerstr. 42, A-1090, Vienna, Austria.
| | - P Zima
- Faculty of Chemistry, Institute of Inorganic Chemistry, University of Vienna, Währingerstr. 42, A-1090, Vienna, Austria
| | - W Moser
- Faculty of Chemistry, Institute of Inorganic Chemistry, University of Vienna, Währingerstr. 42, A-1090, Vienna, Austria
| | - H Uguz
- Faculty of Chemistry, Institute of Inorganic Chemistry, University of Vienna, Währingerstr. 42, A-1090, Vienna, Austria
| | - M G Bartmann
- Faculty of Chemistry, Institute of Inorganic Chemistry, University of Vienna, Währingerstr. 42, A-1090, Vienna, Austria
| | - P Steier
- Faculty of Physics, Isotope Physics, University of Vienna, Währingerstr. 17, A-1090, Vienna, Austria
| | - K Hain
- Faculty of Physics, Isotope Physics, University of Vienna, Währingerstr. 17, A-1090, Vienna, Austria
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Qiao J, Ransby D, Steier P. Deciphering anthropogenic uranium sources in the equatorial northwest Pacific margin. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 806:150482. [PMID: 34844331 DOI: 10.1016/j.scitotenv.2021.150482] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Revised: 09/14/2021] [Accepted: 09/16/2021] [Indexed: 06/13/2023]
Abstract
This work reports the first high-resolution deposition records of anthropogenic uranium (236U and 233U) in a sediment core taken at the continental slope of the Philippine Sea off Mindanao Island in the equatorial northwest Pacific Ocean. Two notable peaks were observed in both profiles of 236U and 233U concentrations, with a narrower peak in 1951-1957 corresponding to close-in Pacific Proving Grounds (PPG) signal, and a broader peak in 1960s-1980s corresponding to the global fallout from nuclear weapons testing. 236U and 233U areal cumulative inventories in the studied sediment core are (2.79 ± 0.20) ∙ 1012 atom ∙ m-2 and (3.12 ± 0.41) ∙ 1010 atom ∙ m-2, respectively, about 20-30% of reported 233U and 236U inventories from the direct global fallout deposition. The overall 233U/236U atomic ratios obtained in this work vary within (0.3-3.5) ∙ 10-2, with an integrated 233U/236U atomic ratio of (1.12 ± 0.17) ∙ 10-2. The contribution from global fallout and close-in PPG fallout to 236U in the sediment core is estimated to be about 69% and 31%, respectively. We believe the main driving process for anthropogenic uranium deposition in the Philippine sediment is continuous scavenging of dissolved 236U from the surface seawater by sinking particles.
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Affiliation(s)
- Jixin Qiao
- Department of Environmental Engineering, Technical University of Denmark, DTU Risø Campus, DK-4000 Roskilde, Denmark.
| | - Daniela Ransby
- Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany
| | - Peter Steier
- VERA Laboratory, Faculty of Physics, Isotope Research, University of Vienna, Währinger Straße 17, A-1090 Vienna, Austria
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First study on 236U in environmental samples from Bangladesh by ICP-MS/MS prior to the operation of its first nuclear power plant. J Radioanal Nucl Chem 2021. [DOI: 10.1007/s10967-021-07931-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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Shao Y, Yang G, Luo M, Xu D, Tazoe H, Yamada M, Ma L. Background and fingerprint characteristics of anthropogenic 236U and 137Cs in soil and road dust samples collected from Beijing and Zhangjiakou, China. CHEMOSPHERE 2021; 263:127909. [PMID: 32822937 DOI: 10.1016/j.chemosphere.2020.127909] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 07/29/2020] [Accepted: 08/02/2020] [Indexed: 06/11/2023]
Abstract
236U has attracted more attention as an environmental tracer in recent years. However, in-depth study of 236U in terrestrial environments is still rare in China. Data on 236U and 137Cs concentrations in soil and road dust samples collected from Beijing and Zhangjiakou, China were obtained to demonstrate the background and distinct characteristics of anthropogenic 236U and 137Cs. 236U and 137Cs were detected in the range of (1.10-7.90) × 107 atoms g-1 and below the method limits of detection to 5.30 Bq kg-1. A clear characteristic was observed in road dust, where 236U concentrations increased with decreasing of sample particle size. Soil samples showed an irregular characteristic, but the highest 236U concentrations were observed in particle size fraction of <0.053 mm in both samples. This phenomenon was caused by U chemical properties, higher specific surface areas and organic compounds in fine particles. Anthropogenic radionuclides fingerprint characteristics in <0.053 mm samples were specially discussed. 236U/238U atom ratios were detected in the range of (0.627-3.38) × 10-8. A weak correlation between anthropogenic 236U and natural U isotopes were observed. The intermediate correlation between 236U and 137Cs indicated somewhat distinct migration behavior of these two radionuclides in soil after release to the environment. The released amount of 236U from global fallout during the period of atmospheric nuclear weapons testing was roughly estimated to be 1300 ± 448 kg. These results could be used as fingerprint information for anthropogenic 236U migration behavior and tracer application in environment.
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Affiliation(s)
- Yang Shao
- Beijing Engineering Research Center of Radiographic Techniques and Equipment, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, 100049, China; Department of Radiation Chemistry, Institute of Radiation Emergency Medicine, Hirosaki University, 66-1 Hon-cho, Hirosaki, Aomori, 036-8564, Japan
| | - Guosheng Yang
- Department of Radiation Chemistry, Institute of Radiation Emergency Medicine, Hirosaki University, 66-1 Hon-cho, Hirosaki, Aomori, 036-8564, Japan; National Institutes for Quantum and Radiological Science and Technology, 4-9-1 Anagawa, Inage, Chiba, 263-8555, Japan
| | - Min Luo
- Beijing Engineering Research Center of Radiographic Techniques and Equipment, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, 100049, China
| | - Diandou Xu
- Beijing Engineering Research Center of Radiographic Techniques and Equipment, Institute of High Energy Physics, Chinese Academy of Sciences, 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; Central Laboratory, Marine Ecology Research Institute, 300 Iwawada, Onjuku, Isumi, Chiba, 299-5105, Japan.
| | - Lingling Ma
- Beijing Engineering Research Center of Radiographic Techniques and Equipment, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, 100049, China.
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Jaegler H, Gourgiotis A, Steier P, Golser R, Diez O, Cazala C. Pushing Limits of ICP-MS/MS for the Determination of Ultralow 236U/ 238U Isotope Ratios. Anal Chem 2020; 92:7869-7876. [PMID: 32370491 DOI: 10.1021/acs.analchem.0c01121] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Determination of uranium isotope ratios is of great expedience for assessing its origin in environmental samples. In particular, the 236U/238U isotope ratio provides a powerful tool to discriminate between the different sources of uranium (uranium ore, geochemical background, and uranium from anthropogenic activities). However, in the environment, this ratio is typically below 10-8. This low abundance of 236U and the presence in large excess of major isotopes (mainly 238U and 235U) complicates the accurate detection of 236U signal by mass spectrometry and thus highly sensitive analytical instruments providing high abundance sensitivity are required. This work pushes the limits of triple quadrupole-based ICP-MS technology for accurate detection of 236U/238U isotope ratios down to 10-10, which is so far mainly achievable by AMS. Coupled with an efficient desolvating module, N2O was used as the reaction gas in the collision reaction cell of the ICP-MS/MS. This configuration allows a significant decrease of the uranium polyatomic interferences (235UH+ ions) and an accurate determination of low 236U/238U isotope ratios. This new methodology was successfully validated through measurements of certified reference material from 10-7 to 10-9 and then through comparisons with AMS measurement results for ratios down to 10-10. This is the first time that 236U/238U isotope ratios as low as 10-10 were determined by ICP-MS/MS. The possibility of measuring low 236U/238U isotope ratios can offer a large variety of geochemical applications in particular for the determination of uranium sources in the environment.
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Affiliation(s)
- Hugo Jaegler
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PSE-ENV/SEDRE/LELI, 31 Avenue de la Division Leclerc, 92260 Fontenay-aux-Roses, France
| | - Alkiviadis Gourgiotis
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PSE-ENV/SEDRE/LELI, 31 Avenue de la Division Leclerc, 92260 Fontenay-aux-Roses, France
| | - Peter Steier
- University of Vienna, Faculty of Physics, Isotope Research and Nuclear Physics, Vienna Environmental Research Accelerator, Währinger Straße 17, 1090 Vienna, Austria
| | - Robin Golser
- University of Vienna, Faculty of Physics, Isotope Research and Nuclear Physics, Vienna Environmental Research Accelerator, Währinger Straße 17, 1090 Vienna, Austria
| | - Olivier Diez
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PSE-ENV/SEDRE/LELI, 31 Avenue de la Division Leclerc, 92260 Fontenay-aux-Roses, France
| | - Charlotte Cazala
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PSE-ENV/SEDRE/LELI, 31 Avenue de la Division Leclerc, 92260 Fontenay-aux-Roses, France
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Froehlich MB, Akber A, McNeil SD, Tims SG, Fifield LK, Wallner A. Anthropogenic 236U and Pu at remote sites of the South Pacific. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2019; 205-206:17-23. [PMID: 31082674 DOI: 10.1016/j.jenvrad.2019.05.003] [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: 02/13/2019] [Revised: 05/04/2019] [Accepted: 05/04/2019] [Indexed: 06/09/2023]
Abstract
Anthropogenic radionuclides, like 236U and 239,240Pu, are present in the environment as a result of global fallout from nuclear weapons tests conducted in the 1950s and 1960s and can potentially be used as tracers in soil erosion and sediment movement studies. Here, we report data on 236U and 239,240Pu in soil samples from the Motueka Valley (New Zealand) and for the first time from two remote islands Rarotonga and Atiu (Cook Islands) in the South Pacific. 236U and 239,240Pu were measured using Accelerator Mass Spectrometry (AMS) at the Australian National University. The 236U and 239Pu isotope concentrations versus soil depth and the 240Pu/239Pu and 236U/239Pu isotope ratios are discussed for each site. The radionuclide depth dependence revealed any soil disturbance, whereas the isotopic signatures indicated the source of the radionuclides' origin.
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Affiliation(s)
- M B Froehlich
- Department of Nuclear Physics, Australian National University, Canberra, ACT, 2601, Australia.
| | - A Akber
- Department of Nuclear Physics, Australian National University, Canberra, ACT, 2601, Australia
| | - S D McNeil
- Department of Nuclear Physics, Australian National University, Canberra, ACT, 2601, Australia
| | - S G Tims
- Department of Nuclear Physics, Australian National University, Canberra, ACT, 2601, Australia
| | - L K Fifield
- Department of Nuclear Physics, Australian National University, Canberra, ACT, 2601, Australia
| | - A Wallner
- Department of Nuclear Physics, Australian National University, Canberra, ACT, 2601, Australia
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Shao Y, Yang G, Xu D, Yamada M, Tazoe H, Luo M, Cheng H, Yang K, Ma L. First report on global fallout 236U and uranium atom ratios in soils from Hunan Province, China. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2019; 197:1-8. [PMID: 30463028 DOI: 10.1016/j.jenvrad.2018.11.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2018] [Revised: 11/13/2018] [Accepted: 11/13/2018] [Indexed: 06/09/2023]
Abstract
More nuclear power plants continue to be built in China. Due to its long half-life, radiotoxicity and potential application as an environmental tracer, 236U is one of the most important artificial radionuclides deserving more study since activity data are important for risk assessment. However, the ultra-trace activity of 236U and its dilution by natural uranium isotopes make it difficult to distinguish its sources and there are only limited global fallout 236U data for present in Chinese environmental samples. In order to understand the background levels for uranium isotopes, especially 236U, and clarify their sources, inductively coupled plasma tandem mass spectrometry (ICP-MS/MS) was applied to analyze uranium isotopes in 48 soil samples from Hunan Province, China. The 234U, 235U, 238U and 236U concentrations were measured as 9.91-33.7, 0.312-1.43, 6.63-28.7 Bq kg-1 and (1.61-21.3) × 107 atoms g-1, while, the 236U/238U, 234U/238U and 235U/238U atom ratios were (0.470-4.91) × 10-8, (5.10-9.31) × 10-5, and (7.11-7.82) × 10-3, respectively. The uranium isotopic fractionation may be due to irrigation of the agricultural lands where the samples were collected. Considering the facts that neither previous nuclear tests nor nuclear accidents had occurred in Hunan Province and the present 236U/238U atom ratios were included in the range of global fallout values in other areas, it may be concluded that 236U in soils from Hunan Province is mainly from global fallout. To the best of the authors' knowledge, the presence of global fallout 236U in soil samples from China has been confirmed for the first time, and these values may be useful as background data for risk assessment in the future.
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Affiliation(s)
- Yang Shao
- Beijing Engineering Research Center of Radiographic Techniques and Equipment, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, 100049, China; Department of Radiation Chemistry, Institute of Radiation Emergency Medicine, Hirosaki University, 66-1 Hon-cho, Hirosaki, Aomori, 036-8564, Japan; School of Nuclear Science and Technology, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Guosheng Yang
- Department of Radiation Chemistry, Institute of Radiation Emergency Medicine, Hirosaki University, 66-1 Hon-cho, Hirosaki, Aomori, 036-8564, Japan
| | - Diandou Xu
- Beijing Engineering Research Center of Radiographic Techniques and Equipment, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, 100049, China
| | - Masatoshi Yamada
- Department of Radiation Chemistry, Institute of Radiation Emergency Medicine, Hirosaki University, 66-1 Hon-cho, Hirosaki, Aomori, 036-8564, Japan.
| | - Hirofumi Tazoe
- Department of Radiation Chemistry, Institute of Radiation Emergency Medicine, Hirosaki University, 66-1 Hon-cho, Hirosaki, Aomori, 036-8564, Japan
| | - Min Luo
- Beijing Engineering Research Center of Radiographic Techniques and Equipment, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, 100049, China
| | - Hangxin Cheng
- Key Laboratory of Geochemical Cycling of Carbon and Mercury in the Earth's Critical Zone, Institute of Geophysical and Geochemical Exploration, Chinese Academy of Geological Science, Langfang, 065000, China
| | - Ke Yang
- Key Laboratory of Geochemical Cycling of Carbon and Mercury in the Earth's Critical Zone, Institute of Geophysical and Geochemical Exploration, Chinese Academy of Geological Science, Langfang, 065000, China
| | - Lingling Ma
- Beijing Engineering Research Center of Radiographic Techniques and Equipment, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, 100049, China.
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Salmani-Ghabeshi S, Chamizo E, Christl M, Miró C, Pinilla-Gil E, Cereceda-Balic F. Presence of 236U and 239,240Pu in soils from Southern Hemisphere. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2018; 192:478-484. [PMID: 30096706 DOI: 10.1016/j.jenvrad.2018.08.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2018] [Revised: 08/01/2018] [Accepted: 08/05/2018] [Indexed: 06/08/2023]
Abstract
236U, 239Pu and 240Pu are present in soils mainly as a result of the local- and global-fallout from the atmospheric nuclear weapons tests carried out mainly in the 1950's and 1960's. In this work we provide new data on the presence of 236U and 239,240Pu in surface soils (i.e. up to 5 cm depth) from Chile and Africa. The results were obtained by low-energy Accelerator Mass Spectrometry (AMS). In the case of the Chilean samples, 236U/239Pu atom ratios show a high variability and are in general higher than the reported value for the global fallout in the Northern Hemisphere, ranging from 0.2 to 1.5. The 236U atomic concentrations range from 3.5 × 106 to 9.1 × 106 atoms/g, and are at least two orders of magnitude lower than the reported values in the Northern Hemisphere. The measured 240Pu/239Pu atom ratio in soils from South-Africa and Mozambique are of about 0.17, in agreement with the expected one for global-fallout at those coordinates. To best knowledge of the authors the present work is the first publication on 236U concentrations and 236U/239Pu atom ratios in soils from South-America and Africa.
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Affiliation(s)
- S Salmani-Ghabeshi
- Departamento de Química Analítica e IACYS, Universidad de Extremadura Avda. de Elvas, s/n, E-06006 Badajoz, Spain
| | - E Chamizo
- Centro Nacional de Aceleradores, Avda. Thomas Alba Edison, 7, 41092 Sevilla, Spain
| | - M Christl
- Laboratory of Ion Beam Physics, ETH Zurich, Otto Stern Weg 5, CH-8093 Zurich, Switzerland
| | - C Miró
- Departamento de Física Aplicada, Avda. de la Universidad s/n E-10071 Cáceres, Spain.
| | - E Pinilla-Gil
- Departamento de Química Analítica e IACYS, Universidad de Extremadura Avda. de Elvas, s/n, E-06006 Badajoz, Spain
| | - F Cereceda-Balic
- Laboratorio de Química Ambiental, Centro de Tecnologías Ambientales (CETAM), Universidad Técnica Federico Santa María, Casilla 110-V, Valparaíso, Chile
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12
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Development and application of mass spectrometric techniques for ultra-trace determination of 236U in environmental samples-A review. Anal Chim Acta 2017; 995:1-20. [DOI: 10.1016/j.aca.2017.09.029] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Revised: 08/23/2017] [Accepted: 09/19/2017] [Indexed: 02/04/2023]
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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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Yang G, Tazoe H, Yamada M. Determination of 236 U in environmental samples by single extraction chromatography coupled to triple-quadrupole inductively coupled plasma-mass spectrometry. Anal Chim Acta 2016; 944:44-50. [DOI: 10.1016/j.aca.2016.09.033] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Revised: 09/08/2016] [Accepted: 09/23/2016] [Indexed: 10/20/2022]
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Tims SG, Froehlich MB, Fifield LK, Wallner A, De Cesare M. (236)U and (239,)(240)Pu ratios from soils around an Australian nuclear weapons test site. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2016; 151 Pt 3:563-567. [PMID: 26141189 DOI: 10.1016/j.jenvrad.2015.06.020] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2015] [Revised: 06/17/2015] [Accepted: 06/24/2015] [Indexed: 06/04/2023]
Abstract
The isotopes (236)U, (239)Pu and (240)Pu are present in surface soils as a result of global fallout from nuclear weapons tests carried out in the 1950's and 1960's. These isotopes potentially constitute artificial tracers of recent soil erosion and sediment movement. Only Accelerator Mass Spectrometry has the requisite sensitivity to measure all three isotopes at these environmental levels. Coupled with its relatively high throughput capabilities, this makes it feasible to conduct studies of erosion across the geographical extent of the Australian continent. In the Australian context, however, global fallout is not the only source of these isotopes. As part of its weapons development program the United Kingdom carried out a series of atmospheric and surface nuclear weapons tests at Maralinga, South Australia in 1956 and 1957. The tests have made a significant contribution to the Pu isotopic abundances present in the region around Maralinga and out to distances ∼1000 km, and impact on the assessment techniques used in the soil and sediment tracer studies. Quantification of the relative fallout contribution derived from detonations at Maralinga is complicated owing to significant contamination around the test site from numerous nuclear weapons safety trials that were also carried out around the site. We show that (236)U can provide new information on the component of the fallout that is derived from the local nuclear weapons tests, and highlight the potential of (236)U as a new fallout tracer.
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Affiliation(s)
- S G Tims
- Department of Nuclear Physics, Research School of Physics and Engineering, Australian National University, Canberra, ACT 2601, Australia.
| | - M B Froehlich
- Department of Nuclear Physics, Research School of Physics and Engineering, Australian National University, Canberra, ACT 2601, Australia
| | - L K Fifield
- Department of Nuclear Physics, Research School of Physics and Engineering, Australian National University, Canberra, ACT 2601, Australia
| | - A Wallner
- Department of Nuclear Physics, Research School of Physics and Engineering, Australian National University, Canberra, ACT 2601, Australia
| | - M De Cesare
- Department of Nuclear Physics, Research School of Physics and Engineering, Australian National University, Canberra, ACT 2601, Australia
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Srncik M, Tims SG, De Cesare M, Fifield LK. First measurements of (236)U concentrations and (236)U/(239)Pu isotopic ratios in a Southern Hemisphere soil far from nuclear test or reactor sites. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2014; 132:108-114. [PMID: 24631872 DOI: 10.1016/j.jenvrad.2014.02.022] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2013] [Revised: 02/24/2014] [Accepted: 02/24/2014] [Indexed: 06/03/2023]
Abstract
The variation of the (236)U and (239)Pu concentrations as a function of depth has been studied in a soil profile at a site in the Southern Hemisphere well removed from nuclear weapon test sites. Total inventories of (236)U and (239)Pu as well as the (236)U/(239)Pu isotopic ratio were derived. For this investigation a soil core from an undisturbed forest area in the Herbert River catchment (17°30' - 19°S) which is located in north-eastern Queensland (Australia) was chosen. The chemical separation of U and Pu was carried out with a double column which has the advantage of the extraction of both elements from a relatively large soil sample (∼20 g) within a day. The samples were measured by Accelerator Mass Spectrometry using the 14UD pelletron accelerator at the Australian National University. The highest atom concentrations of both (236)U and (239)Pu were found at a depth of 2-3 cm. The (236)U/(239)Pu isotopic ratio in fallout at this site, as deduced from the ratio of the (236)U and (239)Pu inventories, is 0.085 ± 0.003 which is clearly lower than the Northern Hemisphere value of ∼0.2. The (236)U inventory of (8.4 ± 0.3) × 10(11) at/m(2) was more than an order of magnitude lower than values reported for the Northern Hemisphere. The (239)Pu activity concentrations are in excellent agreement with a previous study and the (239+240)Pu inventory was (13.85 ± 0.29) Bq/m(2). The weighted mean (240)Pu/(239)Pu isotopic ratio of 0.142 ± 0.005 is slightly lower than the value for global fallout, but our results are consistent with the average ratio of 0.173 ± 0.027 for the southern equatorial region (0-30°S).
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Affiliation(s)
- M Srncik
- Department of Nuclear Physics, Research School of Physics and Engineering, Australian National University, Canberra, ACT 0200, Australia.
| | - S G Tims
- Department of Nuclear Physics, Research School of Physics and Engineering, Australian National University, Canberra, ACT 0200, Australia
| | - M De Cesare
- Department of Nuclear Physics, Research School of Physics and Engineering, Australian National University, Canberra, ACT 0200, Australia
| | - L K Fifield
- Department of Nuclear Physics, Research School of Physics and Engineering, Australian National University, Canberra, ACT 0200, Australia
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Tortorello R, Widom E, Renwick WH. Use of uranium isotopes as a temporal and spatial tracer of nuclear contamination in the environment. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2013; 124:287-300. [PMID: 23871969 DOI: 10.1016/j.jenvrad.2013.06.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2012] [Revised: 06/14/2013] [Accepted: 06/16/2013] [Indexed: 06/02/2023]
Abstract
The Fernald Feed Materials Production Center (FFMPC) was established in 1951 to process natural uranium (U) ore, enriched uranium (EU) and depleted uranium (DU). This study tests the utility of U isotopic ratios in sediment cores and lichens as indicators of the aerial extent, degree and timing of anthropogenic U contamination, using the FFMPC as a test case. An 80-cm-long sediment core was extracted from an impoundment located approximately 6.7 km southwest of the FFMPC. Elemental concentrations of thorium (2.7-6.2 μg g(-1)) and U (0.33-1.33 μg g(-1)) as well as major and minor U isotopes were analyzed in the core. The lack of measurable (137)Cs in the deepest sample as well as a natural (235)U/(238)U signature and no measurable (236)U, are consistent with pre-FFMPC activity. Anomalously elevated U with respect to Th concentrations occur in seven consecutive samples immediately above the base of the core (62-76 cm depth). Samples with elevated U concentrations also show variable (235)U/(238)U (0.00645-0.00748), and all contain measurable (236)U ((236)U/(238)U = 2.1 × 10(-6)-3.6 × 10(-5)). Correspondence between the known releases of U dust from the FFMPC through time and variations in sediment core U concentrations, (235)U/(238)U and (236)U/(238)U ratios provide evidence for distinct releases of both DU and EU. Furthermore, these relationships demonstrate that the sediment core serves as a robust archive of past environmental U contamination events. Samples in the upper 40 cm display natural (235)U/(238)U, but measurable (236)U/(238)U ((236)U/(238)U = 5.68 × 10(-6)-1.43 × 10(-5)), further indicating the continued presence of anthropogenic U in present-day sediment. Three local lichen samples were also analyzed, and all display either EU or DU signatures coupled with elevated (236)U/(238)U, recording airborne U contamination from the FFMPC.
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Affiliation(s)
- R Tortorello
- Department of Geology and Environmental Earth Sciences, Miami University, 114 Shideler Hall, Oxford, OH 45056, USA
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Quinto F, Hrnecek E, Krachler M, Shotyk W, Steier P, Winkler SR. Measurements of ²³⁶U in ancient and modern peat samples and implications for postdepositional migration of fallout radionuclides. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2013; 47:5243-5250. [PMID: 23614536 DOI: 10.1021/es400026m] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
(236)U was analyzed in an ombrotrophic peat core representing the last 80 years of atmospheric deposition and a minerotrophic peat sample from the last interglacial period. The determination of (236)U at levels of 10(7) atoms/g was possible by using ultraclean laboratory procedures and accelerator mass spectrometry. The vertical profile of the (236)U/(238)U isotopic ratio along the ombrotrophic peat core represents the first observation of the (236)U bomb peak in a terrestrial environment. A constant level of anthropogenic (236)U with an average (236)U/(238)U isotopic ratio of (1.24 ± 0.08) × 10(-6) in the top layers of the core was observed. Comparing the abundances of the global fallout derived (236)U and (239)Pu along the peat core, the post depositional migration of plutonium clearly exceeds that of uranium. However, the cumulative (236)U/(239)Pu ratio of 0.62 ± 0.31 is in agreement with previous studies on the global fallout uranium and plutonium. In the interglacial peat samples a (236)U/(238)U isotopic ratio of (3.3 ± 0.7) × 10(-12) was detected; although this measurement is an upper limit, it constitutes a significant step forward in the experimental determination of the natural (236)U abundance and represents a true background sample for the ombrotrophic peat core.
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Affiliation(s)
- Francesca Quinto
- European Commission Joint Research Centre, Institute for Transuranium Elements, PO Box 2340, 76125 Karlsruhe, Germany.
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