1
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Guan Y, Fan K, Wang S, Cui L, Wang H, Guo Z, Chen W, He H, Liu Z. Assessment of the depositional characteristics of the Yellow River estuary from 1960s by 239+240Pu and 137Cs. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 912:169473. [PMID: 38141998 DOI: 10.1016/j.scitotenv.2023.169473] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Revised: 12/14/2023] [Accepted: 12/16/2023] [Indexed: 12/25/2023]
Abstract
The spatial and vertical distribution of 239+240Pu and 137Cs in the sediments of the Yellow River Delta was studied to evaluate the deposition dynamics in the Yellow River estuary from 1960s. The activity of 239+240Pu and 137Cs in sediment core ranged from 0.001 to 0.212 Bq/kg and 0.52-2.53 Bq/kg, respectively. A maximum accumulation peak and two secondary accumulation peaks appeared in the sediment core YR2. The average deposition rate of 8.3 cm/y for the Yellow River estuary from 1964 to 1976 was obtained. The proportion of Pu from the Yellow River net input and direct deposition to the total inventory of Pu in the estuary was assessed, with a total inventory of Pu in the abandoned estuary of 7.4 × 1010 Bq and a net input of 2.2 × 1010 Bq from the Yellow River. Pu deposited in the estuary only accounts for 18 % of the total Pu transported by the Yellow River, and most of the Pu is injected into the Bohai Sea with the Yellow River.
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Affiliation(s)
- Yongjing Guan
- Guangxi Key Laboratory for Relativistic Astrophysics, School of Physical Science and Technology, Guangxi University, Nanning 530004, China.
| | - Kaidi Fan
- Guangxi Key Laboratory for Relativistic Astrophysics, School of Physical Science and Technology, Guangxi University, Nanning 530004, China
| | - Shenzhen Wang
- Guangxi Key Laboratory for Relativistic Astrophysics, School of Physical Science and Technology, Guangxi University, Nanning 530004, China
| | - Liangjia Cui
- Guangxi Key Laboratory for Relativistic Astrophysics, School of Physical Science and Technology, Guangxi University, Nanning 530004, China
| | - Huijuan Wang
- Guangxi Key Laboratory for Relativistic Astrophysics, School of Physical Science and Technology, Guangxi University, Nanning 530004, China
| | - Zichen Guo
- Guangxi Key Laboratory for Relativistic Astrophysics, School of Physical Science and Technology, Guangxi University, Nanning 530004, China
| | - Wu Chen
- Guangxi Key Laboratory for Relativistic Astrophysics, School of Physical Science and Technology, Guangxi University, Nanning 530004, China
| | - Hua He
- Guangxi Key Laboratory for Relativistic Astrophysics, School of Physical Science and Technology, Guangxi University, Nanning 530004, China
| | - Zhiyong Liu
- State Key Laboratory of Radiation Medicine and Protection, School for Radiological and Interdisciplinary Sciences (RAD-X) and Collaborative Innovation Centre of Radiation Medicine of Jiangsu Higher Education Institutions, Soochow University, Suzhou 215123, China.
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2
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Zhao G, Shao Y, Luo M, Xu D, Li D, Liu Z, Ma L. Research progress on the analysis and application of radioactive hot particle. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2023; 270:107313. [PMID: 37857023 DOI: 10.1016/j.jenvrad.2023.107313] [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: 09/25/2023] [Revised: 10/10/2023] [Accepted: 10/11/2023] [Indexed: 10/21/2023]
Abstract
Radioactive hot particle is the particulate form of nuclear material that exists in the environment. The U, Pu, Am, Cs, and other radionuclides isotope in the hot particle contain abundant and accurate fingerprint information, such as the origin and age of the nuclear material. The acquisition and analysis of the key information in the hot particle can be equivalent to the analysis of bulk nuclear material, which could directly reflect the real situation of nuclear activities. Therefore, the single particle analysis of hot particles has become an irreplaceable key technology in nuclear safeguards inspection. The rapid identification, screening, locating, and accurate isotope analysis of hot particles from a large number of particles dispersed in environmental media or on the surface of other materials are one of the most important research field in nuclear emergency. In this review, the research process of the analytical methods for hot particles in the last decade was summarized, including the physical character of hot particles, and the techniques of localization, screening, and extraction of hot particles. Furthermore, we also focused on the mass spectrometry technology for the analysis of hot particle. The advantages and disadvantages of the most used mass spectrometry were summarized. Finally, the research trend for hot particle analysis methods was proposed.
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Affiliation(s)
- Guifang Zhao
- Beijing Engineering Research Center of Radiographic Techniques and Equipment, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, 100049, China; State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, 100029, China
| | - Yang Shao
- Beijing Engineering Research Center of Radiographic Techniques and Equipment, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, 100049, 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
| | - Duohong Li
- State Nuclear Security Technology Center, Beijing, 102401, China
| | - Zhiming Liu
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, 100029, 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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3
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López-Lora M, Olszewski G, Chamizo E, Törnquist P, Pettersson H, Eriksson M. Plutonium Signatures in a Dated Sediment Core as a Tool to Reveal Nuclear Sources in the Baltic Sea. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:1959-1969. [PMID: 36690010 PMCID: PMC9910043 DOI: 10.1021/acs.est.2c07437] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Revised: 12/23/2022] [Accepted: 01/04/2023] [Indexed: 06/17/2023]
Abstract
Plutonium distribution was studied in an undisturbed sediment core sampled from the Tvären bay in the vicinity of the Studsvik nuclear facility in Sweden. The complete analysis, including minor isotopes, of the Pu isotope composition (238Pu, 239Pu, 240Pu, 241Pu, 242Pu, and 244Pu) allowed us to establish the Pu origin in this area of the Baltic Sea and to reconstruct the Studsvik aquatic release history. The results show highly enriched 239Pu, probably originating from the Swedish nuclear program in the 1960s and 1970s and the handling of high burn-up nuclear fuel in the later years. In addition, the 244Pu/239Pu atomic ratio for the global fallout period between 1958 and 1965 is suggested to be (7.94 ± 0.31)·10-5. In the bottom layer of the sediment, dated 1953-1957, we detected a higher average 244Pu/239Pu ratio of (1.51 ± 0.11)·10-4, indicating the possible impact of the first US thermonuclear tests (1952-1958).
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Affiliation(s)
- Mercedes López-Lora
- Department
of Health, Medicine and Caring Sciences (HMV), Linköping University, 58183Linköping, Sweden
| | - Grzegorz Olszewski
- Department
of Health, Medicine and Caring Sciences (HMV), Linköping University, 58183Linköping, Sweden
- Faculty
of Chemistry, Department of Environmental Chemistry and Radiochemistry,
Laboratory of Toxicology and Radiation Protection, University of Gdańsk, Wita Stwosza 63, 80-308Gdańsk, Poland
| | - Elena Chamizo
- Centro
Nacional de Aceleradores (CNA), Universidad de Sevilla, Junta de Andalucía,
Consejo Superior de Investigaciones Científicas, Parque científico y tecnológico Cartuja, Thomas Alva Edison 7, 41092Sevilla, Spain
| | - Per Törnquist
- Department
of Health, Medicine and Caring Sciences (HMV), Linköping University, 58183Linköping, Sweden
| | - Håkan Pettersson
- Department
of Medical Radiation Physics, and Department of Health, Medicine and
Caring Sciences, Linköping University, 58183Linköping, Sweden
| | - Mats Eriksson
- Department
of Health, Medicine and Caring Sciences (HMV), Linköping University, 58183Linköping, Sweden
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4
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Zhang W, Hou X, Dang H, Chen N, Zhang H. Distribution and migration of 239,240Pu in soil profiles in North China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 857:159471. [PMID: 36265634 DOI: 10.1016/j.scitotenv.2022.159471] [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: 07/24/2022] [Revised: 10/11/2022] [Accepted: 10/12/2022] [Indexed: 06/16/2023]
Abstract
The source, vertical distribution and migration behavior of plutonium in five soil profiles (from forest, grassland and desert areas) in northern China were investigated. The average 240Pu/239Pu atomic ratio of 0.184 ± 0.022 observed in these samples is in good agreement with the reported value of global fallout, suggesting that the global fallout is the major source of plutonium in northern China. The 239,240Pu inventories in five soil profiles ranges from 43.3 Bq/m2 to 175 Bq/m2, lying in the reported range for global fallout in the similar latitude band. The effective convection velocity (0.04-0.16 cm/y) and effective dispersion coefficient (0.13-0.41cm2/y) of plutonium in different soil profiles derived using the CDE model varies significantly, attributed to multi-factors including location, topography, climate and soil types. The results showed that the migration of plutonium in grassland soil is significantly slow compared to other type of soil, especially desert soil.
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Affiliation(s)
- Weichao Zhang
- State Key Laboratory of Loess and Quaternary Geology, Shaanxi Key Laboratory of Accelerator Mass Spectrometry Technology and Application, Xi'an AMS Center, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, China; Northwest Institute of Nuclear Technology, Xi'an 710024, China
| | - Xiaolin Hou
- State Key Laboratory of Loess and Quaternary Geology, Shaanxi Key Laboratory of Accelerator Mass Spectrometry Technology and Application, Xi'an AMS Center, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, China; Technical University of Denmark, Department of Environmental and Resource Engineering, Risø Campus, DK-4000 Roskilde, Denmark.
| | - Haijun Dang
- Northwest Institute of Nuclear Technology, Xi'an 710024, China
| | - Ning Chen
- State Key Laboratory of Loess and Quaternary Geology, Shaanxi Key Laboratory of Accelerator Mass Spectrometry Technology and Application, Xi'an AMS Center, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, China
| | - Haitao Zhang
- Northwest Institute of Nuclear Technology, Xi'an 710024, China
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5
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Integrating the theory of sampling into a nuclear forensic investigation. Appl Radiat Isot 2022; 190:110513. [DOI: 10.1016/j.apradiso.2022.110513] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Revised: 08/12/2022] [Accepted: 10/11/2022] [Indexed: 11/17/2022]
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6
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Effect of land use and vegetation coverage on level and distribution of plutonium isotopes in the northern Loess Plateau, China. J Radioanal Nucl Chem 2022. [DOI: 10.1007/s10967-022-08675-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
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7
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Johansen MP, Child DP, Collins R, Cook M, Davis J, Hotchkis MAC, Howard DL, Howell N, Ikeda-Ohno A, Young E. Radioactive particles from a range of past nuclear events: Challenges posed by highly varied structure and composition. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 842:156755. [PMID: 35718169 DOI: 10.1016/j.scitotenv.2022.156755] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Revised: 06/10/2022] [Accepted: 06/13/2022] [Indexed: 06/15/2023]
Affiliation(s)
- Mathew P Johansen
- Australian Nuclear Science and Technology Organisation (ANSTO), Locked Bag 2001, Kirrawee DC, NSW 2232, Australia.
| | - David P Child
- Australian Nuclear Science and Technology Organisation (ANSTO), Locked Bag 2001, Kirrawee DC, NSW 2232, Australia
| | | | - Megan Cook
- International Atomic Energy Agency (IAEA), Environmental Laboratories, Monaco
| | - Joel Davis
- Australian Nuclear Science and Technology Organisation (ANSTO), Locked Bag 2001, Kirrawee DC, NSW 2232, Australia
| | - Michael A C Hotchkis
- Australian Nuclear Science and Technology Organisation (ANSTO), Locked Bag 2001, Kirrawee DC, NSW 2232, Australia
| | - Daryl L Howard
- Australian Synchrotron, 800 Blackburn Road, Clayton, Victoria 3168, Australia
| | - Nicholas Howell
- Australian Nuclear Science and Technology Organisation (ANSTO), Locked Bag 2001, Kirrawee DC, NSW 2232, Australia
| | - Atsushi Ikeda-Ohno
- Japan Atomic Energy Agency (JAEA), 2-4 Shirakata, Tokai-mura, Naka-gun, Ibaraki-ken 319-1195, Japan
| | - Emma Young
- Australian Nuclear Science and Technology Organisation (ANSTO), Locked Bag 2001, Kirrawee DC, NSW 2232, Australia
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8
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Zhang H, Hou X, Qiao J, Lin J. Determination of 241Am in Environmental Samples: A Review. Molecules 2022; 27:molecules27144536. [PMID: 35889408 PMCID: PMC9315525 DOI: 10.3390/molecules27144536] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Revised: 07/11/2022] [Accepted: 07/12/2022] [Indexed: 02/04/2023] Open
Abstract
The determination of 241Am in the environment is of importance in monitoring its release and assessing its environmental impact and radiological risk. This paper aims to give an overview about the recent developments and the state-of-art analytical methods for 241Am determination in environmental samples. Thorough discussions are given in this paper covering a wide range of aspects, including sample pre-treatment and pre-concentration methods, chemical separation techniques, source preparation, radiometric and mass spectrometric measurement techniques, speciation analyses, and tracer applications. The paper focuses on some hyphenated separation methods based on different chromatographic resins, which have been developed to achieve high analytical efficiency and sample throughput for the determination of 241Am. The performances of different radiometric and mass spectrometric measurement techniques for 241Am are evaluated and compared. Tracer applications of 241Am in the environment, including speciation analyses of 241Am, and applications in nuclear forensics are also discussed.
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Affiliation(s)
- Haitao Zhang
- Northwest Institute of Nuclear Technology, Xi’an 710024, China; (H.Z.); (J.L.)
| | - Xiaolin Hou
- Department of Environmental and Resource Engineering, Technical University of Denmark, DTU Risø Campus, 4000 Roskilde, Denmark;
| | - Jixin Qiao
- Department of Environmental and Resource Engineering, Technical University of Denmark, DTU Risø Campus, 4000 Roskilde, Denmark;
- Correspondence:
| | - Jianfeng Lin
- Northwest Institute of Nuclear Technology, Xi’an 710024, China; (H.Z.); (J.L.)
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9
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Łokas E, Wachniew P, Baccolo G, Gaca P, Janko K, Milton A, Buda J, Komędera K, Zawierucha K. Unveiling the extreme environmental radioactivity of cryoconite from a Norwegian glacier. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 814:152656. [PMID: 34954174 DOI: 10.1016/j.scitotenv.2021.152656] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Revised: 11/29/2021] [Accepted: 12/20/2021] [Indexed: 06/14/2023]
Abstract
This study is a first survey of the occurrence of artificial (137Cs, 241Am, 207Bi, Pu isotopes) and natural (210Pb, 228Ac, 214Bi, 40K) radionuclides in Norwegian cryoconite. Cryoconite samples were collected before (12 samples) and after (5 samples) a rainfall event, after which 7 cryoconite holes dissapeared. The concentrations of radionuclides in cryoconite samples from the Blåisen Glacier are compared with data from the Arctic and Alpine glaciers. Cryoconite samples from the studied glacier had extremely high activity concentrations of 137Cs, 241Am, 207Bi and 239+240Pu (up to 25,000 Bq/kg, 58 Bq/kg, 13 Bq/kg and 131 Bq/kg, respectively) and also high concentrations of organic matter (OM), comparing to other Scandinavian and Arctic glaciers, reaching up to ~40% of total mass. The outstandingly high concentrations of 137Cs, 241Am, Pu isotopes, and 207Bi on the Blåisen Glacier are primarily related to bioaccumulation of radionuclides in organic-rich cryoconite and might be enhanced by additional transfers of contamination from the tundra by lemmings during their population peaks. The presumed influence of intense rainfall on radionuclide concentrations in the cryoconite was not confirmed.
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Affiliation(s)
- Edyta Łokas
- Department of Mass Spectrometry, Institute of Nuclear Physics Polish Academy of Sciences, Kraków, Poland.
| | - Przemysław Wachniew
- Faculty of Physics and Applied Computer Science, AGH University of Science and Technology, Kraków, Poland
| | - Giovanni Baccolo
- Department of Environmental and Earth Sciences, University of Milano-Bicocca, Milano, Italy
| | - Paweł Gaca
- GAU-Radioanalytical Laboratories, Ocean and Earth Science, University of Southampton, National Oceanography Centre, European Way, Southampton, United Kingdom
| | - Karel Janko
- Laboratory of Fish Genetics, Institute of Animal Physiology and Genetics, Academy of Sciences of the Czech Republic, Libechov, Czech Republic; Department of Biology and Ecology, Faculty of Science, University of Ostrava, Ostrava, Czech Republic
| | - Andrew Milton
- GAU-Radioanalytical Laboratories, Ocean and Earth Science, University of Southampton, National Oceanography Centre, European Way, Southampton, United Kingdom
| | - Jakub Buda
- Department of Animal Taxonomy and Ecology, Adam Mickiewicz Unversity, Poznań, Poland
| | - Kamila Komędera
- Mössbauer Spectroscopy Laboratory, Institute of Physics, Pedagogical University, Kraków, Poland
| | - Krzysztof Zawierucha
- Department of Animal Taxonomy and Ecology, Adam Mickiewicz Unversity, Poznań, Poland
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10
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Zhong N, Li L, Yang X, Zhao Y. Analytical Methods for the Determination of 90Sr and 239,240Pu in Environmental Samples. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27061912. [PMID: 35335276 PMCID: PMC8952015 DOI: 10.3390/molecules27061912] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 02/15/2022] [Accepted: 02/22/2022] [Indexed: 11/16/2022]
Abstract
Artificial long-lived radionuclides such as 90Sr and 239,240Pu have been long released into the environment by human nuclear activities, which have a profound impact on the ecological environment. It is of great significance to monitor the concentration of these radionuclides for environmental safety. This paper summarizes and critically discusses the separation and measurement methods for ultra-trace determination of 90Sr, 239Pu, and 240Pu in the environment. After selecting the measurement method, it is necessary to consider the decontamination of the interference from matrix elements and the key elements, and this involves the choice of the separation method. Measurement methods include both radiometric methods and non-radiometric methods. Radiometric methods, including alpha spectroscopy, liquid scintillation spectrometry, etc., are commonly used methods for measuring 239+240Pu and 90Sr. Mass spectrometry, as the representative of non-radiometric measurement methods, has been regarded as the most promising analytical method due to its high absolute sensitivity, low detection limit, and relatively short sample-analysis time. Through the comparison of various measurement methods, the future development trend of radionuclide measurement is prospected in this review. The fully automatic and rapid analysis method is a highlight. The new mass spectrometer with ultra-high sensitivity shows strong analytical capabilities for extremely low concentrations of 90Sr, 239Pu, and 240Pu, and it is expected to develop determination methods with higher sensitivity and lower detection limit.
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11
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Bouisset P, Nohl M, Cossonnet C, Boulet B, Thomas S, Cariou N, Salaun G. Contribution of close-in fallout from the French atmospheric tests in inventories of 137Cs, 241Am and plutonium (238, 239, 240) in Gambier Islands (French Polynesia) - Signatures of stratospheric fallout in the Southern Hemisphere. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2021; 235-236:106624. [PMID: 34059369 DOI: 10.1016/j.jenvrad.2021.106624] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Revised: 04/10/2021] [Accepted: 04/13/2021] [Indexed: 06/12/2023]
Abstract
The inventories of 137Cs (503 ± 34 Bq.m-2), 241Am (11.3 ± 1.2 Bq.m-2), 241Pu (33.7 ± 3.4 Bq.m-2), 238Pu (6.82 ± 0.87 Bq.m-2) and 239+240Pu (113.0 ± 5.9 Bq.m-2), sum of 239Pu (100 ± 11 Bq.m-2) and 240Pu (14.5 ± 1.7 Bq.m-2), in the Gambier archipelago (23°S) of the French Polynesia, are well higher the global fallout at this latitude, in unequal proportions for the different radionuclides. (240Pu/239Pu)AR (AR: atomic ratio) of 0.0394 ± 0.0062, and (241Pu/239Pu)AR of (2.03 ± 0.39)10-4, confirm that the overwhelmingly dominant source of these radionuclides comes from local fallout during the 1970s of the French atmospheric tests of Moruroa and Fangataufa located nearly 400 km from Gambier. The signatures of the local fallout were deduced from the excess of its inventory in 137Cs and from the mixing lines established from the signatures of the global fallout, some of the test sites and the isotopic ratios measured in Gambier. Signatures obtained are 2.0 ± 0.4 for 137Cs/239+240Pu, 0.045 ± 0.008 for 238Pu/239+240Pu, 0.031 ± 0.009 for 241Am/239+240Pu, 0.092 ± 0.027 for 241Pu/239+240Pu, 0.0163 ± 0.0049 for (240Pu/239Pu)AR, (0.78 ± 0.23)10-4 for (241Pu/239Pu)AR. The concordance of the mixing lines of the [(240Pu/239Pu)AR, (241Pu/239Pu)AR] and the linear regression of these ratios measured in the stratosphere (40°S) during the 1970s, indicates that the signatures of the close-in deposition are also those of the stratospheric injections of the French tests. The signatures of stratospheric fallout in the Southern Hemisphere were evaluated by considering that the fission energy of these injections represents 11% and that of the Northern Hemisphere represents 89% and that the isotopic ratios of stratospheric injections remained the same over the period 1970-1974. The activity ratios deducted are 21.9 ± 0.1 in 137Cs/239+240Pu, 0.11 ± 0.05 in 238Pu/239+240Pu, 1.03 ± 0.12 in 241Pu/239+240Pu and 0.35 ± 0.04 in 241Am/239+240Pu. The associated atom ratios are 0.157 ± 0.011 for (240Pu/239Pu)AR and (8.33 ± 0.48)10-4 for (241Pu/239Pu)AR. These signatures appear to be consistent with the results of the inventories at Hiva Oa, located more than 1,000 km north of both French test sites, and with those found in the Australian continent, in regions not impacted by UK-test debris. The proportions of close-in tropospheric fallout from the French tests are about 90% in Gambier. They represent a proportion in the inventories of 40% for the 137Cs, 60% for 241Am and in the range between 80 and 90% for Pu isotopes.
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Affiliation(s)
- P Bouisset
- Institut de Radioprotection et de Sûreté nucléaire, BP 182, 98725, Vairao, Tahiti, French Polynesia.
| | - M Nohl
- Institut de Radioprotection et de Sûreté nucléaire, BP 182, 98725, Vairao, Tahiti, French Polynesia
| | - C Cossonnet
- Institut de Radioprotection et de Sûreté nucléaire, Bât 501, bois des Rames, 91400, Orsay, France
| | - B Boulet
- Institut de Radioprotection et de Sûreté nucléaire, Bât 501, bois des Rames, 91400, Orsay, France
| | - S Thomas
- Institut de Radioprotection et de Sûreté nucléaire, Bât 501, bois des Rames, 91400, Orsay, France
| | - N Cariou
- Institut de Radioprotection et de Sûreté nucléaire, Bât 501, bois des Rames, 91400, Orsay, France
| | - G Salaun
- Institut de Radioprotection et de Sûreté nucléaire, Cadarache Bât 153, 13108, St Paul-lès-Durance, France
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12
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Analyzing alpha emitting isotopes of Pu, Am and Cm from NPP water samples: an intercomparison of Nordic radiochemical laboratories. J Radioanal Nucl Chem 2021. [DOI: 10.1007/s10967-021-07913-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
AbstractRadioanalytical methods for the determination of isotopes of Pu, Am and Cm in water samples from nuclear power plants were compared and further developed in a Nordic project (Optimethod) through two intercomparison exercises among Nordic laboratories. With this intercomparison, the analytical performance of some laboratories was improved by modification of the analytical method and adopting new techniques. The obtained results from the two intercomparisons for alpha emitting transuranium isotopes are presented, and the lessons learnt from these intercomparison exercises are discussed.
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13
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Determination of ultra-trace level plutonium isotopes in soil samples by triple-quadrupole inductively coupled plasma-mass spectrometry with mass-shift mode combined with UTEVA chromatographic separation. Talanta 2021; 234:122652. [PMID: 34364461 DOI: 10.1016/j.talanta.2021.122652] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 06/21/2021] [Accepted: 06/22/2021] [Indexed: 11/23/2022]
Abstract
Although triple-quadrupole inductively coupled plasma-mass spectrometry (ICP-MS/MS) has become an attractive technique for the measurement of long-lived radionuclides, the abundance sensitivity, isobaric and polyatomic ions interferences seriously restrict the application. The spectral peak tailing and uranium hydrides (UH+, UH2+) from 238U have a serious influence on the accurate measurement of 239Pu and 240Pu, especially for the ultra-trace level plutonium isotopes in the higher uranium sample. A new method was developed using ICP-MS/MS measurement in mass-shift mode with collision-reaction gas combined with a chemical separation procedure. As O2 readily converted Pu+ ion to PuO2+, while disassociated the interfering diatomic ions of interfering elements (U, Pb, Hg, Tl, etc.), the interferences from these elements were completely eliminated if plutonium was detected as PuO2+ at the m/z more than 270. By the mass filter in MS/MS mode combined with O2 as reaction gas the lower peak tailing of 238U+ (<5 × 10-12) was significantly suppressed. By this way, the 238UO2H+/238UO2+ atomic ratio was reduced to 4.82 × 10-9, which is significantly lower than that of other collision-reaction gas modes. Interferences from Pb, Hg and Tl polyatomic ions were also completely eliminated. Thus, accurate measurement of ultra-trace level 239Pu in high uranium sample solutions with the 239Pu/238U concentration ratio of 10-10 was achieved by the mass-shift mode with 0.15 mL/min O2/He + 12.0 mL/min He as collision-reaction gas, and high elimination efficiency of uranium interferences up to 1014 can be obtained by combination with the chemical separation using a single UTEVA resin column. The developed method can be applied to accurately determine the fg level 239Pu in high uranium samples, such as large-size deep seawater, deep soil and sediment, uranium debris of nuclear fuel.
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14
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Cwanek A, Eriksson M, Holm E. The study of Canadian Arctic freshwater system toward radioactive contamination - status in 1999. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2021; 226:106454. [PMID: 33161355 DOI: 10.1016/j.jenvrad.2020.106454] [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: 07/07/2020] [Revised: 10/23/2020] [Accepted: 10/27/2020] [Indexed: 06/11/2023]
Abstract
This work provides a novel data set on accumulations of both anthropogenic (137Cs, 238Pu, 239+240Pu, 241Am) and natural (210Pb, 226Ra, 232Th) radionuclides and an element (K). Sampling of soils and lake sediments was accomplished in 1999 during Tundra Northwest (TNW-99) international expedition to a remote region of the Canadian Arctic. The sediment ages and sedimentation rates were determined. The obtained results overall indicated a high geographical diversity of contamination levels and trends. Accumulation rates were also differential, and a sediment focusing contribution was distinctly visible. Radioactive pollution was found to be lower relative to temperate counterparts. The activity ratios of anthropogenic radionuclides corresponded to global fallout as a prevailing source in the entire examined area. The post-Chernobyl radiocaesium was observed for the westernmost lake only. The elevated level of 137Cs and 239+240Pu in the topmost sediment at the northern and eastern Arctic Archipelago was attributed to recent resuspension and subsequent redistribution of radionuclides.
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Affiliation(s)
- Anna Cwanek
- Institute of Nuclear Physics, Polish Academy of Sciences, Radzikowskiego 152, 31-342, Krakow, Poland.
| | - Mats Eriksson
- Swedish Radiation Safety Authority, 171 16, Stockholm, Sweden; Department of Health, Medicine and Caring Sciences (HMV), Linköping University, 581 83, Linköping, Sweden
| | - Elis Holm
- Department of Radiation Physics, Sahlgrenska Unversitetssjukhuset, 413 45, Göteborg, Sweden
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15
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Cwanek A, Mietelski JW, Łokas E, Olech MA, Anczkiewicz R, Misiak R. The radioactive contamination study in south-western Greenland tundra in 2012-2013. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2020; 212:106125. [PMID: 31818733 DOI: 10.1016/j.jenvrad.2019.106125] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Revised: 11/15/2019] [Accepted: 11/28/2019] [Indexed: 06/10/2023]
Abstract
The paper presents results of the radioecological investigation carried out in south-western Greenland shoreline. There were examined over 50 samples of lichens and mosses collected from 7 locations during two scientific expeditions conducted in the summer of 2012-2013. The levels, trends and the most likely origin were determined for following natural and artificial radionuclides: 90Sr, 137Cs, 230, 232Th, 234, 238U, 238, 239+240Pu and 241Am. The radioactive pollution was found as relatively low, reaching the maximum values at: 25.3 ± 2.04 Bq/kg for 90Sr, 293 ± 27 Bq/kg for 137Cs, 4.01 ± 0.13 Bq/kg for 239+240Pu, 0.1381 ± 0.0070 Bq/kg for 238Pu and 1.90 ± 0.21 Bq/kg of 241Am, 9.15 ± 0.48 Bq/kg for 230Th, 25.1 ± 1.2 Bq/kg for 232Th, 7.5 ± 1.5 Bq/kg for 234U and 7.26 ± 0.80 Bq/kg for 238U. Both activity and mass isotopic ratio assays revealed dominant contribution of the global fallout + SNAP 9A on the presence of plutonium isotopes and 241Am in Greenland tundra. However, noticeable deviations of 241Am/239+240Pu and to a lesser extend of 240Pu/239Pu ratios from the GF level have been observed. The origin of 137Cs was evidently connected with the coexistence of global and Chernobyl fallout, while the presence of 90Sr was caused by nuclear weapon tests and affected by leaching process. The seaborne signature of uranium isotopes was manifested in research material as well.
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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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16
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Salbu B, Lind OC. Analytical techniques for charactering radioactive particles deposited in the environment. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2020; 211:106078. [PMID: 31677430 DOI: 10.1016/j.jenvrad.2019.106078] [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: 05/29/2019] [Revised: 10/13/2019] [Accepted: 10/13/2019] [Indexed: 06/10/2023]
Abstract
Since 1945, a series of nuclear and radiological sources have contributed to the release of radioactive particles containing refractory elements into the environment. Several years of research have demonstrated that the particle composition will depend on the source, while the release scenarios will influence particle properties of relevance for environmental transfer. Radioactive particles can also carry sufficient amount of radioactivity (MBq) and represent point sources of radiological concern. Most radiological assessment models, however, are based on bulk concentrations, assuming that radionuclides in the environment are evenly distributed. In contrast, radioactive particles and thereby doses are unevenly distributed, while leaching of radionuclides from particles prior to measurements can be partial, potentially leading to underestimation of inventories. For areas affected by particle contamination, information on particle characteristics controlling the particle weathering rates and remobilization of particle associated radionuclides will therefore be essential to reduce the overall uncertainties of the impact assessments. The present paper will focus on analytical strategies, from screening techniques applicable for identifying hot spots in the field, fractionation techniques and single particle extraction techniques as a preparatory mean to apply non-destructive solid state speciation techniques, till leaching techniques applied sequentially to obtain information on binding mechanisms, mobility and potential bioavailability. Thus, a combination of techniques should be utilized to characterize radioactive particles in order to improve environmental assessments for areas affected by radioactive particle fallout.
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Affiliation(s)
- Brit Salbu
- CERAD CoE, Faculty of Environmental Sciences and nature Resource Management, Norwegian University of Life Sciences, 1432, Aas, Norway
| | - Ole Christian Lind
- CERAD CoE, Faculty of Environmental Sciences and nature Resource Management, Norwegian University of Life Sciences, 1432, Aas, Norway.
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17
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Zhang W, Hou X. Level, distribution and sources of plutonium in the coastal areas of China. CHEMOSPHERE 2019; 230:587-595. [PMID: 31125887 DOI: 10.1016/j.chemosphere.2019.05.094] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2019] [Revised: 05/02/2019] [Accepted: 05/12/2019] [Indexed: 06/09/2023]
Abstract
Plutonium is an important radioactive element in view of its biological toxicity and environmental impact. The two most important isotopes of plutonium, 239Pu and 240Pu, in the surface soil from the coastal area of China were determined using radiochemical separation combined with inductively coupled plasma mass spectrometry (ICP-MS) measurement. The average of the measured 240Pu/239Pu atomic ratios in all these samples is 0.186 ± 0.021, which is in good agreement with the ratio of global fallout of the nuclear weapons tests. This indicates that the major source of plutonium in this region is global fallout, and there is no measurable release of plutonium from any nuclear power plant along the coast of China. The 239,240Pu concentrations in all 71 soil samples range from 0.002 mBq/g to 0.670 mBq/g, which fall in the range of the reported values in the background area not directly influenced by nuclear activities. The anthropogenic disturbance of sampling sites, vegetation coverage of land, precipitation rate and organic substance content and erosion of soil have significant influence on the level of plutonium in the surface soil.
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Affiliation(s)
- Weichao Zhang
- State Key Laboratory of Loess and Quaternary Geology, Shaanxi Key Laboratory of Accelerator Mass Spectrometry Technology and Application, Xi'an AMS Center, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an, 710061, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Xiaolin Hou
- State Key Laboratory of Loess and Quaternary Geology, Shaanxi Key Laboratory of Accelerator Mass Spectrometry Technology and Application, Xi'an AMS Center, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an, 710061, China; Center for Nuclear Technologies, Technical University of Denmark, DTU Nutech, 4000, Roskilde, Denmark; CAS Center of Excellence in Quaternary Science and Global Change, Xi'an, 710061, China; Open Studio for Oceanic-Continental Climate and Environment Changes, Pilot National Laboratory for Marine Science and Technology (Qingdao), Qingdao, 266061, China.
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18
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Hou X, Zhang W, Wang Y. Determination of Femtogram-Level Plutonium Isotopes in Environmental and Forensic Samples with High-Level Uranium Using Chemical Separation and ICP-MS/MS Measurement. Anal Chem 2019; 91:11553-11561. [DOI: 10.1021/acs.analchem.9b01347] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- Xiaolin Hou
- State Key Laboratory of Loess and Quaternary Geology, Shaanxi Key Laboratory of Accelerator Mass Spectrometry Technology and Application, Xi’an AMS Center, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an 710061, China
- Center for Nuclear Technologies, Technical University of Denmark, DTU Nutech, Roskilde DK-4000, Denmark
- CAS Center of Excellence in Quaternary Science and Global Change, Xi’an 710061, China
- Open Studio for Oceanic-Continental Climate and Environment Changes, Pilot National Laboratory for Marine Science and Technology (Qingdao), Qingdao 266061, China
| | - Weichao Zhang
- State Key Laboratory of Loess and Quaternary Geology, Shaanxi Key Laboratory of Accelerator Mass Spectrometry Technology and Application, Xi’an AMS Center, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an 710061, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yanyun Wang
- State Key Laboratory of Loess and Quaternary Geology, Shaanxi Key Laboratory of Accelerator Mass Spectrometry Technology and Application, Xi’an AMS Center, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an 710061, China
- University of Chinese Academy of Sciences, Beijing 100049, China
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19
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240Pu/ 239Pu and 242Pu/ 239Pu atom ratios of Japanese monthly atmospheric deposition samples during 1963-1966. Sci Rep 2019; 9:8105. [PMID: 31147582 PMCID: PMC6543033 DOI: 10.1038/s41598-019-44352-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Accepted: 05/14/2019] [Indexed: 11/29/2022] Open
Abstract
Global fallout plutonium isotopic ratios from the 1960s are important for the use of Pu as environmental tracers. We measured the 240Pu/239Pu and 242Pu/239Pu atomic ratios of monthly atmospheric deposition samples collected in Tokyo and Akita, Japan during March 1963 to May 1966. To our knowledge, our results represent the first data measured for actual atmospheric deposition samples collected continuously during the 1960s. Both atomic ratios increased rapidly from March 1963 to June 1963, followed by a gradual increase until September 1963. Then, both ratios declined with a half-life of approximately 5.6 months. The observed temporal changes of the ratios were likely caused by the upper-stratospheric input of nuclear debris from high-yield atmospheric nuclear weapon testing during 1961–62, followed by its downward transport to the troposphere.
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20
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Bellucci JJ, Whitehouse MJ, Aleshin M, Eriksson M. Simultaneous Pu and U Isotope Nuclear Forensics on an Environmentally Recovered Hot Particle. Anal Chem 2019; 91:5599-5604. [DOI: 10.1021/acs.analchem.8b04809] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- J. J. Bellucci
- Department of Geosciences, Swedish Museum of Natural History, SE-104 05 Stockholm, Sweden
| | - M. J. Whitehouse
- Department of Geosciences, Swedish Museum of Natural History, SE-104 05 Stockholm, Sweden
| | - M. Aleshin
- International Atomic Energy Agency, Department of Safeguards, 1220 Vienna, Austria
| | - M. Eriksson
- Strålsäkerhetsmyndigheten, Swedish Radiation Safety Authority, SE-171 16 Stockholm, Sweden
- Department of Medical Physics, Department of Medical and Health Sciences, Linköping University, SE-581 83 Linköping, Sweden
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21
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Thakur P, Ward AL. Sources and distribution of 241Am in the vicinity of a deep geologic repository. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2019; 26:2328-2344. [PMID: 30465246 DOI: 10.1007/s11356-018-3712-5] [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: 09/17/2018] [Accepted: 11/06/2018] [Indexed: 06/09/2023]
Abstract
The detection, distribution, and long-term behavior of 241Am in the terrestrial environment at the Waste Isolation Pilot Plant (WIPP) site were assessed using historical data from an independent monitoring program conducted by the Carlsbad Environmental Monitoring & Research Center (CEMRC), and its predecessor organization the Environmental Evaluation Group (EEG). An analysis of historical data indicates frequent detections of trace levels of 241Am in the WIPP environment. Positive detections and peaks in 241Am concentrations in ambient air samples generally occur during the March to June timeframe, which is when strong and gusty winds in the area frequently give rise to blowing dust. A study of long-term measurements of 241Am in the WIPP environment suggest that the resuspension of previously contaminated soils is likely the primary source of americium in the ambient air samples from WIPP and its vicinity. Furthermore, the 241Am/239 + 240Pu ratio in aerosols and soils was reasonably consistent from year to year and was in agreement with the global fallout ratios. Higher than normal activity concentrations of 241Am and 241Am/239 + 240Pu ratios were measured in aerosol samples during 2014 as a result of February 14, 2014 radiation release event from the WIPP underground. However, after a brief spike, the activity concentrations of 241Am have returned to the normal background levels. The long-term monitoring data suggest there is no persistent contamination and no lasting increase in radiological contaminants in the region that can be considered significant by any health-based standard.
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Affiliation(s)
- Punam Thakur
- Carlsbad Environmental Monitoring & Research Center, 1400 University Drive, Carlsbad, New Mexico, 88220, USA.
| | - Anderson L Ward
- U.S. Department of Energy, Carlsbad Field Office, 4021 National Parks Highway, Carlsbad, New Mexico, 88220, USA
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22
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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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23
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Thakur P, Ward AL. 241Pu in the environment: insight into the understudied isotope of plutonium. J Radioanal Nucl Chem 2018. [DOI: 10.1007/s10967-018-5946-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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24
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Salbu B, Kashparov V, Lind OC, Garcia-Tenorio R, Johansen MP, Child DP, Roos P, Sancho C. Challenges associated with the behaviour of radioactive particles in the environment. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2018; 186:101-115. [PMID: 28941957 DOI: 10.1016/j.jenvrad.2017.09.001] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2017] [Revised: 08/31/2017] [Accepted: 09/01/2017] [Indexed: 06/07/2023]
Abstract
A series of different nuclear sources associated with the nuclear weapon and fuel cycles have contributed to the release of radioactive particles to the environment. Following nuclear weapon tests, safety tests, conventional destruction of weapons, reactor explosions and fires, a major fraction of released refractory radionuclides such as uranium (U) and plutonium (Pu) were present as entities ranging from sub microns to fragments. Furthermore, radioactive particles and colloids have been released from reprocessing facilities and civil reactors, from radioactive waste dumped at sea, and from NORM sites. Thus, whenever refractory radionuclides are released to the environment following nuclear events, radioactive particles should be expected. Results from many years of research have shown that particle characteristics such as elemental composition depend on the source, while characteristics such as particle size distribution, structure, and oxidation state influencing ecosystem transfer depend also on the release scenarios. When radioactive particles are deposited in the environment, weathering processes occur and associated radionuclides are subsequently mobilized, changing the apparent Kd. Thus, particles retained in soils or sediments are unevenly distributed, and dissolution of radionuclides from particles may be partial. For areas affected by particle contamination, the inventories can therefore be underestimated, and impact and risk assessments may suffer from unacceptable large uncertainties if radioactive particles are ignored. To integrate radioactive particles into environmental impact assessments, key challenges include the linking of particle characteristics to specific sources, to ecosystem transfer, and to uptake and retention in biological systems. To elucidate these issues, the EC-funded COMET and RATE projects and the IAEA Coordinated Research Program on particles have revisited selected contaminated sites and archive samples. This COMET position paper summarizes new knowledge on key sources that have contributed to particle releases, including particle characteristics based on advanced techniques, with emphasis on particle weathering processes as well as on heterogeneities in biological samples to evaluate potential uptake and retention of radioactive particles.
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Affiliation(s)
- Brit Salbu
- CERAD CoE Environmental Radioactivity, Faculty of Environmental Sciences and Nature Resource Management, Norwegian University of Life Sciences (NMBU), 1432 Aas, Norway.
| | - Valery Kashparov
- CERAD CoE Environmental Radioactivity, Faculty of Environmental Sciences and Nature Resource Management, Norwegian University of Life Sciences (NMBU), 1432 Aas, Norway; National University of Life and Environmental Sciences of Ukraine (NUBiP of Ukraine), Ukraine
| | - Ole Christian Lind
- CERAD CoE Environmental Radioactivity, Faculty of Environmental Sciences and Nature Resource Management, Norwegian University of Life Sciences (NMBU), 1432 Aas, Norway
| | | | - Mathew P Johansen
- Australian Nuclear Science and Technology Organization (ANSTO), Australia
| | - David P Child
- Australian Nuclear Science and Technology Organization (ANSTO), Australia
| | - Per Roos
- Technical University of Denmark (DTU), Denmark
| | - Carlos Sancho
- Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas (CIEMAT), Spain
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25
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Thakur P, Khaing H, Salminen-Paatero S. Plutonium in the atmosphere: A global perspective. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2017; 175-176:39-51. [PMID: 28432864 DOI: 10.1016/j.jenvrad.2017.04.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2017] [Revised: 04/06/2017] [Accepted: 04/09/2017] [Indexed: 06/07/2023]
Abstract
A number of potential source terms have contributed plutonium isotopes to the atmosphere. The atmospheric nuclear weapon tests conducted between 1945 and 1980 and the re-entry of the burned SNAP-9A satellite in 1964, respectively. It is generally believed that current levels of plutonium in the stratosphere are negligible and compared with the levels generally found at surface-level air. In this study, the time trend analysis and long-term behavior of plutonium isotopes (239+240Pu and 238Pu) in the atmosphere were assessed using historical data collected by various national and international monitoring networks since 1960s. An analysis of historical data indicates that 239+240Pu concentration post-1984 is still frequently detectable, whereas 238Pu is detected infrequently. Furthermore, the seasonal and time-trend variation of plutonium concentration in surface air followed the stratospheric trends until the early 1980s. After the last Chinese test of 1980, the plutonium concentrations in surface air dropped to the current levels, suggesting that the observed concentrations post-1984 have not been under stratospheric control, but rather reflect the environmental processes such as resuspension. Recent plutonium atmospheric air concentrations data show that besides resuspension, other environmental processes such as global dust storms and biomass burning/wildfire also play an important role in redistributing plutonium in the atmosphere.
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Affiliation(s)
- P Thakur
- Carlsbad Environmental Monitoring & Research Center, 1400 University Drive, Carlsbad, NM 88220, USA.
| | - H Khaing
- Carlsbad Environmental Monitoring & Research Center, 1400 University Drive, Carlsbad, NM 88220, USA
| | - S Salminen-Paatero
- Department of Chemistry - Radiochemistry, P.O. Box 55, 00014, University of Helsinki, Finland
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26
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Present status and perspective of radiochemical analysis of radionuclides in Nordic countries. J Radioanal Nucl Chem 2016. [DOI: 10.1007/s10967-016-4741-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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27
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Thakur P. Source term estimation and the isotopic ratio of radioactive material released from the WIPP repository in New Mexico, USA. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2016; 151 Pt 1:193-203. [PMID: 26492395 DOI: 10.1016/j.jenvrad.2015.10.009] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2015] [Revised: 10/07/2015] [Accepted: 10/08/2015] [Indexed: 06/05/2023]
Abstract
After almost 15 years of operations, the Waste Isolation Pilot Plant (WIPP) had one of its waste drums breach underground as a result of a runaway chemical reaction in the waste it contained. This incident occurred on February 14, 2014. Moderate levels of radioactivity were released into the underground air. A small portion of the contaminated underground air also escaped to the surface through the ventilation system and was detected approximately 1 km away from the facility. According to the source term estimation, the actual amount of radioactivity released from the WIPP site was less than 1.5 mCi. The highest activity detected on the surface was 115.2 μBq/m(3) for (241)Am and 10.2 μBq/m(3) for (239+240)Pu at a sampling station located 91 m away from the underground air exhaust point and 81.4 μBq/m(3) of (241)Am and 5.8 μBq/m(3) of (239+240)Pu at a monitoring station located approximately 1 km northwest of the WIPP facility. The dominant radionuclides released were americium and plutonium, in a ratio that matches the content of the breached drum. Air monitoring across the WIPP site intensified following the first reports of radiation detection underground to determine the extent of impact to WIPP personnel, the public, and the environment. In this paper, the early stage monitoring data collected by an independent monitoring program conducted by the Carlsbad Environmental Monitoring & Research Center (CEMRC) and an oversight monitoring program conducted by the WIPP's management and operating contractor, the Nuclear Waste Partnership (NWP) LLC were utilized to estimate the actual amount of radioactivity released from the WIPP underground. The Am and Pu isotope ratios were measured and used to support the hypothesis that the release came from one drum identified as having breached that represents a specific waste stream with this radionuclide ratio in its inventory. This failed drum underwent a heat and gas producing reaction that overpowered its vent and lifted its lid to allow release of waste into the underground air.
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Affiliation(s)
- P Thakur
- Carlsbad Environmental Monitoring & Research Center, 1400 University Drive, Carlsbad, NM 88220, USA.
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28
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Xu Y, Qiao J, Pan S, Hou X, Roos P, Cao L. Plutonium as a tracer for soil erosion assessment in northeast China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2015; 511:176-185. [PMID: 25544336 DOI: 10.1016/j.scitotenv.2014.12.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2014] [Revised: 12/02/2014] [Accepted: 12/02/2014] [Indexed: 06/04/2023]
Abstract
Soil erosion is one of the most serious environmental and agricultural problems faced by human society. Assessing intensity is an important issue for controlling soil erosion and improving eco-environmental quality. The suitability of the application of plutonium (Pu) as a tracer for soil erosion assessment in northeast China was investigated by comparing with that of 137Cs. Here we build on preliminary work, in which we investigated the potential of Pu as a soil erosion tracer by sampling additional reference sites and potential erosive sites, along the Liaodong Bay region in northeast China, for Pu isotopes and 137Cs. 240Pu/239Pu atomic ratios in all samples were approximately 0.18, which indicated that the dominant source of Pu was the global fallout. Pu showed very similar distribution patterns to those of 137Cs at both uncultivated and cultivated sites. 239+240Pu concentrations in all uncultivated soil cores followed an exponential decline with soil depth, whereas at cultivated sites, Pu was homogenously distributed in plow horizons. Factors such as planted crop types, as well as methods and frequencies of irrigation and tillage were suggested to influence the distribution of radionuclides in cultivated land. The baseline inventories of 239+240Pu and 137Cs were 88.4 and 1688 Bq m(-2) respectively. Soil erosion rates estimated by 239+240Pu tracing method were consistent with those obtained by the 137Cs method, confirming that Pu is an effective tracer with a similar tracing behavior to that of 137Cs for soil erosion assessment.
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Affiliation(s)
- Yihong Xu
- School of Geographic and Oceanographic Sciences, Nanjing University, Nanjing 210023, China
| | - Jixin Qiao
- Center for Nuclear Technologies, Technical University of Denmark, Risø Campus, DK-4000 Roskilde, Denmark
| | - Shaoming Pan
- School of Geographic and Oceanographic Sciences, Nanjing University, Nanjing 210023, China.
| | - Xiaolin Hou
- Center for Nuclear Technologies, Technical University of Denmark, Risø Campus, DK-4000 Roskilde, Denmark; Xi'an AMS Center, SKLLQG, Institute of Earth Environment, CAS, Xi'an 710075, China.
| | - Per Roos
- Center for Nuclear Technologies, Technical University of Denmark, Risø Campus, DK-4000 Roskilde, Denmark
| | - Liguo Cao
- School of Geographic and Oceanographic Sciences, Nanjing University, Nanjing 210023, China
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Xu Y, Qiao J, Hou X, Pan S, Roos P. Determination of plutonium isotopes (238Pu, 239Pu, 240Pu, 241Pu) in environmental samples using radiochemical separation combined with radiometric and mass spectrometric measurements. Talanta 2014; 119:590-5. [DOI: 10.1016/j.talanta.2013.11.061] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2013] [Revised: 11/18/2013] [Accepted: 11/23/2013] [Indexed: 11/28/2022]
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30
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Xu Y, Qiao J, Hou X, Pan S. Plutonium in soils from northeast China and its potential application for evaluation of soil erosion. Sci Rep 2013; 3:3506. [PMID: 24336360 PMCID: PMC3864049 DOI: 10.1038/srep03506] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2013] [Accepted: 11/28/2013] [Indexed: 11/09/2022] Open
Abstract
Surface and soil core samples from northeast China were analyzed for Pu isotopes. The measured (240)Pu/(239)Pu atomic ratios and (239 + 240)Pu/(137)Cs activity ratios revealed that the global fallout is the dominant source of Pu and (137)Cs at these sites. Migration behavior of Pu varying with land type and human activities resulted in different distribution of Pu in surface soils. A sub-surface maximum followed by exponential decline of (239 + 240)Pu concentrations was observed in an undisturbed soil core, with a total (239 + 240)Pu inventory of 86.9 Bq/m(2) and more than 85% accumulated in 0 ~ 20 cm layers. While only half inventory of Pu was obtained in another soil core and no sub-surface maximum value occurred. Erosion of topsoil in the site should be the most possible reason for the significantly lower Pu inventory, which is also supported by the reported (137)Cs profiles. These results demonstrated that Pu could be applied as an ideal substitute of (137)Cs for soil erosion study in the future.
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Affiliation(s)
- Yihong Xu
- 1] The Key Laboratory of Coastal and Island Development of Ministry of Education, Nanjing University, Nanjing 210093, China [2] Center for Nuclear Technologies, Technical University of Denmark, Risø Campus, Roskilde 4000, Denmark
| | - Jixin Qiao
- Center for Nuclear Technologies, Technical University of Denmark, Risø Campus, Roskilde 4000, Denmark
| | - Xiaolin Hou
- 1] Center for Nuclear Technologies, Technical University of Denmark, Risø Campus, Roskilde 4000, Denmark [2] Xi'an AMS Center, SKLLQG, Institute of Earth Environment, CAS, Xi'an 710075, China
| | - Shaoming Pan
- The Key Laboratory of Coastal and Island Development of Ministry of Education, Nanjing University, Nanjing 210093, China
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Wendel CC, Fifield LK, Oughton DH, Lind OC, Skipperud L, Bartnicki J, Tims SG, Høibråten S, Salbu B. Long-range tropospheric transport of uranium and plutonium weapons fallout from Semipalatinsk nuclear test site to Norway. ENVIRONMENT INTERNATIONAL 2013; 59:92-102. [PMID: 23792418 DOI: 10.1016/j.envint.2013.05.017] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2012] [Revised: 05/22/2013] [Accepted: 05/27/2013] [Indexed: 06/02/2023]
Abstract
A combination of state-of-the-art isotopic fingerprinting techniques and atmospheric transport modelling using real-time historical meteorological data has been used to demonstrate direct tropospheric transport of radioactive debris from specific nuclear detonations at the Semipalatinsk test site in Kazakhstan to Norway via large areas of Europe. A selection of archived air filters collected at ground level at 9 stations in Norway during the most intensive atmospheric nuclear weapon testing periods (1957-1958 and 1961-1962) has been screened for radioactive particles and analysed with respect to the concentrations and atom ratios of plutonium (Pu) and uranium (U) using accelerator mass spectrometry (AMS). Digital autoradiography screening demonstrated the presence of radioactive particles in the filters. Concentrations of (236)U (0.17-23nBqm(-3)) and (239+240)Pu (1.3-782μBqm(-3)) as well as the atom ratios (240)Pu/(239)Pu (0.0517-0.237) and (236)U/(239)Pu (0.0188-0.7) varied widely indicating several different sources. Filter samples from autumn and winter tended to have lower atom ratios than those sampled in spring and summer, and this likely reflects a tropospheric influence in months with little stratospheric fallout. Very high (236)U, (239+240)Pu and gross beta activity concentrations as well as low (240)Pu/(239)Pu (0.0517-0.077), (241)Pu/(239)Pu (0.00025-0.00062) and (236)U/(239)Pu (0.0188-0.046) atom ratios, characteristic of close-in and tropospheric fallout, were observed in filters collected at all stations in Nov 1962, 7-12days after three low-yield detonations at Semipalatinsk (Kazakhstan). Atmospheric transport modelling (NOAA HYSPLIT_4) using real-time meteorological data confirmed that long range transport of radionuclides, and possibly radioactive particles, from Semipalatinsk to Norway during this period was plausible. The present work shows that direct tropospheric transport of fallout from atmospheric nuclear detonations periodically may have had much larger influence on radionuclide air concentrations and deposition than previously anticipated.
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Affiliation(s)
- Cato Christian Wendel
- Isotope Laboratory, Department of Plant and Environmental Sciences, Agricultural University of Norway, P.O. Box 5003, N-1432 Aas, Norway.
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32
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Thakur P, Ballard S, Nelson R. Plutonium in the WIPP environment: its detection, distribution and behavior. ACTA ACUST UNITED AC 2012; 14:1604-15. [PMID: 22549140 DOI: 10.1039/c2em30027c] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The Waste Isolation Pilot Plant (WIPP) is the only operating deep underground geologic nuclear repository in the United States. It is located in southeastern New Mexico, approximately 655 m (2150 ft) below the surface of the Earth in a bedded Permian evaporite salt formation. This mined geologic repository is designed for the safe disposal of transuranic (TRU) wastes generated from the US defense program. Aerosol and soil samples have been collected near the WIPP site to investigate the sources of plutonium in the WIPP environment since the late 1990s, well before WIPP received its first shipment. Activities of (238)Pu, (239+240)Pu and (241)Am were determined by alpha spectrometry following a series of chemical separations. The concentrations of Al and U were determined in a separate set of samples by inductively coupled plasma mass spectrometry. The annual airborne concentrations of (239+240)Pu during the period from 1998 to 2010 show no systematic interannual variations. However, monthly (239+240)Pu particulate concentrations show a typical seasonal variation with a maximum in spring, the time when strong and gusty winds frequently give rise to blowing dust. Resuspension of soil particles containing weapons fallout is considered to be the predominant source of plutonium in the WIPP area. Further, this work characterizes the source, temporal variation and its distribution with depth in a soil profile to evaluate the importance of transport mechanisms affecting the fate of these radionuclides in the WIPP environment. The mean (137)Cs/(239+240)Pu, (241)Am/(239+240)Pu activity ratio and (240)Pu/(239)Pu atom ratio observed in the WIPP samples are consistent with the source being largely global fallout. There is no evidence of any release from the WIPP contributing to radionuclide concentrations in the environment.
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Affiliation(s)
- P Thakur
- Carlsbad Environmental Monitoring & Research Center, Carlsbad, New Mexico 88220, USA
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Wu F, Zheng J, Liao H, Yamada M, Wan G. Anomalous plutonium isotopic ratios in sediments of Lake Qinghai from the Qinghai-Tibetan Plateau, China. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2011; 45:9188-9194. [PMID: 21950768 DOI: 10.1021/es202315c] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The vertical profiles of (239+240)Pu and (137)Cs activities and (240)Pu/(239)Pu isotopic ratios are determined for three sediment cores of Lake Qinghai from the Qinghai-Tibetan Plateau, China, and compared with those in sediments of another three lakes (Lakes Bosten, Sugan, and Shuangta), the only existing ones closest to Lop Nor area, China's nuclear weapons test site in the northwestern part of the country. The mean inventory of 47.7 ± 18.7 MBq km(-2) for (239+240)Pu activity in Lake Qinghai is comparable to the average value of global fallout expected at the same latitude, yet the mean inventory of 1112.0 ± 78.0 MBq km(-2) for (137)Cs is slightly lower than that of global fallout. Anomalously low (240)Pu/(239)Pu isotopic ratios (0.038-0.125) were found in the 3-6.5 cm deep sediment layers, indicating the trace Pu input from early nuclear weapons research activities at Atomic City in the lake's watershed during the 1950-60s. Model calculation indicated that the Pu input accounted for approximately 5-16% of the total Pu inventory. The observation of low (240)Pu/(239)Pu ratio in the deep sediment layer provided a new time marker for recent sediment dating in the lake and around the area. The results are of great significance to the further understanding of sources, records, and environmental impacts of global and regional nuclear activities in the environment and provide important chronological information for further studies on the water eutrophication process and climatic change, and reconstruction of pollution history of organic contaminants and heavy metals in the watershed of Lake Qinghai.
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Affiliation(s)
- Fengchang Wu
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China.
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Peräjärvi KA, Ihantola S, Pöllänen RC, Toivonen HI, Turunen JA. Determination of (235)U, (239)Pu, (240)Pu, and (241)Am in a nuclear bomb particle using a position-sensitive α-γ coincidence technique. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2011; 45:1528-1533. [PMID: 21247104 DOI: 10.1021/es1033734] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
A nuclear bomb particle containing 1.6 ng of Pu was investigated nondestructively with a position-sensitive α detector and a broad-energy HPGe γ-ray detector. An event-mode data acquisition system was used to record the data. α-γ coincidence counting was shown to be well suited to nondestructive isotope ratio determination. Because of the very small background, the 51.6 keV γ rays of (239)Pu and the 45.2 keV γ rays of (240)Pu were identified, which enabled isotopic ratio calculations. In the present work, the (239)Pu/((239)Pu+(240)Pu) atom ratio was determined to be 0.950 ± 0.010. The uncertainties were much smaller than in the previous more conventional nondestructive studies on this particle. Obtained results are also in good agreement with the data from the destructive mass spectrometric studies obtained previously by other investigators.
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Affiliation(s)
- Kari A Peräjärvi
- STUK - Radiation and Nuclear Safety Authority, Helsinki, Finland.
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Jiménez-Ramos MC, Hurtado S, Chamizo E, García-Tenorio R, León-Vintró L, Mitchell PI. (239)Pu, (240)Pu, and (241)Am determination in hot particles by low level gamma-spectrometry. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2010; 44:4247-4252. [PMID: 20441142 DOI: 10.1021/es100425x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
A nondestructive method based on low-energy, high-resolution photon spectrometry is presented which allows accurate determination of (239)Pu, (240)Pu, and (241)Am (as a daughter of (241)Pu) activities in radioactive particles containing relatively high levels of plutonium isotopes. The proposed method requires only one measurement for the establishment of an absolute efficiency curve. Since the density and composition of the radioactive particles of interest may vary, a self-absorption correction is required for the accurate determination of isotopic activities and ratios. This correction is carried out for each individual particle using the convenient gamma-ray emissions of (241)Am.
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36
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Characterization of radioactive particles using non-destructive alpha spectrometry. Appl Radiat Isot 2010; 68:1754-9. [PMID: 20359900 DOI: 10.1016/j.apradiso.2010.02.014] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2009] [Revised: 11/27/2009] [Accepted: 02/26/2010] [Indexed: 11/20/2022]
Abstract
Spherical particles with known properties were used to demonstrate and test a novel software package known as AASIFIT, which is able to unfold complex alpha spectra. A unique feature of the program is that it uses simulated peak shapes in the fitting process. The experimental reference particles in the testing were artificially produced U particles of diameter 1.4microm and a nuclear bomb particle with a twenty-fold greater diameter, mainly composed of U and Pu dioxides. AASIFIT was used to determine the density of the U particles. In addition, the activities of (239+240)Pu and (241)Am were determined for the nuclear bomb particle and compared to earlier determinations in the literature. The results of this investigation demonstrated that the software can be used to estimate the properties of particles emitting alpha radiation. However, the composition and geometry of the investigated particles need to be known with good accuracy for reliable estimates. Furthermore, uncertainties in the stopping power data, especially for U and Pu, may have an influence on the results obtained from the software.
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37
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Lindahl P, Lee SH, Worsfold P, Keith-Roach M. Plutonium isotopes as tracers for ocean processes: a review. MARINE ENVIRONMENTAL RESEARCH 2010; 69:73-84. [PMID: 19773079 DOI: 10.1016/j.marenvres.2009.08.002] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2009] [Revised: 08/17/2009] [Accepted: 08/18/2009] [Indexed: 05/28/2023]
Abstract
Since the first nuclear weapons tests in the 1940s, pulsed inputs of plutonium isotopes have served as excellent tracers for understanding sources, pathways, dynamics and the fate of pollutants and particles in the marine environment. Due to the well-defined spatial and temporal inputs of Pu, the long half-lives of (240)Pu and (239)Pu and its unique chemical properties, Pu is a potential tracer for various physical and biogeochemical ocean processes, including circulation, sedimentation and biological productivity, and hence a means of assessing the impacts of global climate change. Due to the source dependency of the Pu isotopic signature, plutonium isotopes are beginning to be exploited as tools for the evaluation and improvement of regional and global ocean models that will enhance understanding of past and future changes in the oceans. This paper addresses the major sources of Pu and the physical and biogeochemical behaviour in the marine environment. Finally, the use of Pu isotopes as tracers for various oceanic processes (e.g. water mass transport, particle export, and sedimentation) is considered.
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Affiliation(s)
- Patric Lindahl
- Marine Environment Research Department, Korea Ocean Research and Development Institute, Ansan, P.O. Box 29, Seoul 425-600, Republic of Korea.
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38
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Resonance ionization mass spectrometry of ion beam sputtered neutrals for element- and isotope-selective analysis of plutonium in micro-particles. Anal Bioanal Chem 2009; 395:1911-8. [PMID: 19557397 DOI: 10.1007/s00216-009-2906-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2009] [Revised: 06/05/2009] [Accepted: 06/09/2009] [Indexed: 10/20/2022]
Abstract
Micro-particles containing actinides are of interest for risk assessments of contaminated areas, nuclear forensic analyses, and IAEA as well as Euratom safeguards programs. For their analysis, secondary ion mass spectrometry (SIMS) has been established as the state-of-the-art standard technique. In the case of actinide mixtures within the particles, however, SIMS suffers from isobaric interferences (e.g., (238)U/(238)Pu, (241)Am/(241)Pu). This can be eliminated by applying resonance ionization mass spectrometry which is based on stepwise resonant excitation and ionization of atoms with laser light, followed by mass spectrometric detection of the produced ions, combining high elemental selectivity with the analysis of isotopic compositions. This paper describes the instrumental modifications for coupling a commercial time-of-flight (TOF)-SIMS apparatus with three-step resonant post-ionization of the sputtered neutrals using a high-repetition-rate (kHz) Nd:YAG laser pumped tunable titanium:sapphire laser system. Spatially resolved ion images obtained from actinide-containing particles in TOF-SIMS mode demonstrate the capability for isotopic and spatial resolution. Results from three-step resonant post-ionization of bulk Gd and Pu samples successfully demonstrate the high elemental selectivity of this process.
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