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Zheng J, Tagami K, Uchida S, Shibutani S, Ishida K, Hamamoto T. Assessment of soil-soil solution distribution coefficients of global fallout 237Np and 239Pu in Japanese upland soils. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2023; 266-267:107241. [PMID: 37454645 DOI: 10.1016/j.jenvrad.2023.107241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Revised: 07/05/2023] [Accepted: 07/09/2023] [Indexed: 07/18/2023]
Abstract
Neptunium-237 and 239Pu are important radionuclides in the safety assessment related to geological disposal of radioactive waste because of the possibility of long-term exposure to humans. Mobilities of these radionuclides in the environment are of particular importance for their radiation dose evaluation; therefore, in this study, we have made the assessment of the soil-soil solution distribution coefficient (Kd, L/kg) using global fallout 237Np and 239Pu in Japanese upland soils. The Kd values were determined by extracting these radionuclides from 24 soil samples using a laboratory batch method. The desorption Kd values of 237Np ranged from 3.3 × 102 to 1.0 × 104 L/kg, and their geometric mean (GM) and arithmetic mean (AM) were 1.7 × 103 L/kg and 2.6 × 103 L/kg, respectively. The desorption Kd values of 239Pu were found to vary from 9.4 × 103 to 7.1 × 104 L/kg, and their GM and AM were 3.3 × 104 L/kg and 4.0 × 104 L/kg, respectively. In Japanese upland soils, the Kd value of 239Pu was one order of magnitude higher than that of 237Np.
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Affiliation(s)
- Jian Zheng
- National Institute for Radiological Science, National Institutes for Quantum Science and Technology (QST), 4-9-1 Anagawa, Inage, Chiba, 263-8555, Japan.
| | - Keiko Tagami
- National Institute for Radiological Science, National Institutes for Quantum Science and Technology (QST), 4-9-1 Anagawa, Inage, Chiba, 263-8555, Japan
| | - Shigeo Uchida
- National Institute for Radiological Science, National Institutes for Quantum Science and Technology (QST), 4-9-1 Anagawa, Inage, Chiba, 263-8555, Japan
| | - Sanae Shibutani
- Nuclear Waste Management Organization of Japan, 4-1-23 Shiba, Minato-ku, Tokyo, 108-0014, Japan
| | - Keisuke Ishida
- Nuclear Waste Management Organization of Japan, 4-1-23 Shiba, Minato-ku, Tokyo, 108-0014, Japan
| | - Takafumi Hamamoto
- Nuclear Waste Management Organization of Japan, 4-1-23 Shiba, Minato-ku, Tokyo, 108-0014, Japan
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Ni Y, Bu W, Xiong K, Hu S, Yang C, Cao L. A novel strategy for Pu determination in water samples by automated separation in combination with direct ICP-MS/MS measurement. Talanta 2023; 262:124710. [PMID: 37244244 DOI: 10.1016/j.talanta.2023.124710] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2023] [Revised: 05/11/2023] [Accepted: 05/22/2023] [Indexed: 05/29/2023]
Abstract
Methods for Pu determination in water samples has been longtime studied but they generally involved tedious manual operations. In this context, we proposed a novel strategy for accurate determination of ultra-trace Pu in water samples by the combination of fully automated separation with direct ICP-MS/MS measurement. A recently commercialized extraction resin TK200 was used for single-column separation due to its distinctive nature. Acidified waters up to 1 L were directly loaded to the resin at high flow rate (15 mL min-1) with omitting the frequently used co-precipitation process. Small volumes of dilute HNO3 were used for column washing, and Pu was efficiently eluted within only 2 mL 0.5 mol L-1 HCl-0.1 mol L-1 HF with a stable recovery (65%). This separation procedure was fully automated under the control of user program, meanwhile the final eluent was compatible for direct ICP-MS/MS measurement without extra sample treatment. In that way, both the labor intensity and reagent consumption were minimized compared with existing methods. With the high decontamination (104 to 105) of U in the chemical separation and the further elimination of uranium hydrides under oxygen reaction model during ICP-MS/MS measurement, the overall interference yields of UH+/U+ and UH2+/U+ were down to 10-15. The limits of detection (LODs) of this method reached 0.32 μBq L-1 for 239Pu and 2.00 μBq L-1 for 240Pu, which were much lower than those stipulated in the general guidelines for drinking water standards, suggesting this method was promising in routine or emergency radiation monitoring. Furthermore, the established method was successfully applied in a pilot study to determine global fallout derived Pu in surface glacier samples with extremely low concentrations of 239+240Pu, which suggested the method would also be feasible in glacial chronology studies in the future.
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Affiliation(s)
- Youyi Ni
- Institute of Nuclear Physics and Chemistry, China Academy of Engineering Physics, Mianyang, 621999, China.
| | - Wenting Bu
- Institute of Nuclear Physics and Chemistry, China Academy of Engineering Physics, Mianyang, 621999, China
| | - Ke Xiong
- Institute of Nuclear Physics and Chemistry, China Academy of Engineering Physics, Mianyang, 621999, China
| | - Sheng Hu
- Institute of Nuclear Physics and Chemistry, China Academy of Engineering Physics, Mianyang, 621999, China
| | - Chuting Yang
- Institute of Nuclear Physics and Chemistry, China Academy of Engineering Physics, Mianyang, 621999, China
| | - Liguo Cao
- School of Geography and Tourism, Shanxi Normal University, Xi'an, 710119, China
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Luo M, Liu D, Dai X, Wu Y, Yuan N. Determination of ultra-low level of 239, 240Pu in grass/vegetable sample by compact accelerator mass spectrometry. J Radioanal Nucl Chem 2023. [DOI: 10.1007/s10967-022-08753-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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Lukashenko SN, Edomskaya MA. Plutonium in the Environment: Sources, Dissemination Mechanisms, and Concentrations. BIOL BULL+ 2022. [DOI: 10.1134/s1062359022110139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
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Wu J, Zheng X, Chen J, Yang G, Zheng J, Aono T. Distributions and impacts of plutonium in the environment originating from the Fukushima Daiichi Nuclear Power Plant accident: An overview of a decade of studies. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2022; 248:106884. [PMID: 35398758 DOI: 10.1016/j.jenvrad.2022.106884] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Revised: 03/27/2022] [Accepted: 03/28/2022] [Indexed: 06/14/2023]
Abstract
This paper reviews the current knowledge on plutonium (Pu) isotopic composition (the atom or activity ratios) and activity concentrations of 238Pu, 239Pu, 240Pu, and 241Pu resulting from the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident in 2011. In this critical review, we document the characteristic values of Pu atom or activity ratios (fingerprints) and present their spatial distributions around the FDNPP site. Based on multiple Pu fingerprints (238Pu/239+240Pu activity ratio, 240Pu/239Pu atom ratio, and 241Pu/239Pu atom ratio), we clarify that Pu contamination from the FDNPP accident occurred in a restricted terrestrial area, while Pu in the Northwest Pacific Ocean is still predominately sourced from the Pacific Proving Grounds (PPG) and global fallout. Using a simple two end-member mixing model, we calculate average contributions of Pu from the FDNPP accident of 13 ± 20% (n = 180) in soil samples, 55 ± 32% (n = 38) in leaf litter samples, and 67 ± 26% (n = 129) in air dust/black substances. In the marine environment, the PPG source average contributions are 45 ± 15% (n = 76) in seawater and 42 ± 12% (n = 48) in sediments. The spatial distributions of Pu atom or activity ratios based on existing studies suggest that: 1) in the terrestrial region investigated 80 km northwest of the FDNPP site, the Pu contamination is mainly observed in an area within a 50 km distance, and 2) in the terrestrial region investigated 60 km southwest of the FDNPP site, the Pu contamination is mainly observed in an area within a 30 km distance. Studies of Cs-bearing radioactive particles indicate that Pu occurs as Pu oxide, and the fuel fragments containing Pu that were released from the reactors to the surrounding environment are associated with micron-scale Cs-bearing radioactive particles. We note that the fractionation between Pu and other radionuclides occurred after release. These new findings about the Pu fingerprints around the FDNPP site will help researchers to establish a reference background database for future environmental risk assessment and geochemical study there.
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Affiliation(s)
- Junwen Wu
- Guangdong Provincial Key Laboratory of Marine Disaster Prediction and Prevention & Institute of Marine Sciences, Shantou University, Shantou, 515063, China; Southern Marine Science and Engineering Guangdong Laboratory, Guangzhou, 511458, China
| | - Xuemin Zheng
- Guangdong Provincial Key Laboratory of Marine Disaster Prediction and Prevention & Institute of Marine Sciences, Shantou University, Shantou, 515063, China
| | - Jisheng Chen
- Guangdong Provincial Key Laboratory of Marine Disaster Prediction and Prevention & Institute of Marine Sciences, Shantou University, Shantou, 515063, China
| | - Guosheng Yang
- National Institutes for Quantum Science and Technology, 4-9-1 Anagawa, Inage, Chiba, 263-8555, Japan
| | - Jian Zheng
- National Institutes for Quantum Science and Technology, 4-9-1 Anagawa, Inage, Chiba, 263-8555, Japan.
| | - Tatsuo Aono
- National Institutes for Quantum Science and Technology, 4-9-1 Anagawa, Inage, Chiba, 263-8555, Japan
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Sources and Variability of Plutonium in Chinese Soils: A Statistical Perspective with Moving Average. ATMOSPHERE 2022. [DOI: 10.3390/atmos13050769] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
Abstract
We investigated the different sources and their corresponding impact areas of Pu in Chinese surface soils to illustrate the state-of-the-art of the sources, levels and distributions of 240Pu/239Pu atom ratios as well as 239+240Pu activity concentrations in China. For the first time a moving average strategy in combination with statistical analysis was employed to partition geographic areas in China based on the reported 240Pu/239Pu atom ratio and 239+240Pu concentration data from public literature. During the partitioning, the median (MED) of the dataset was basically employed as a criteria in place of the commonly used arithmetic average (AM). Concisely, three areas were partitioned according to the different influences of Pu from the Lop Nor (LNTS) and Semipalatinsk (STS) test sites and the global fallout. The partitioned Ternary area (80° E–105° E, 35° N–50° N) was supposed to have multiple sources of Pu including the STS and LNTS besides the global fallout, which was characterized with slightly lower 240Pu/239Pu atom ratios (MED = 0.174) as well as elevated 239+240Pu concentrations (MED = 0.416 mBq/g). Meanwhile, the Binary area (35° N–45° N, 100° E–115° E) was considered to have received the extra contribution from the high-yield nuclear tests at the LNTS besides the global fallout, resulting in the highest 240Pu/239Pu atom ratios (MED = 0.200) across China. The remaining area was marked as the Unitary area, where it only received the exclusive contribution of global fallout. Furthermore, through the statistical analysis of the 240Pu/239Pu data in the Unitary area, we recommended a value of 0.186 ± 0.021 (AM ± SD) as a representative or area-specific 240Pu/239Pu atom ratio baseline to characterize the global fallout derived Pu in Chinese soils.
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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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Zheng J, Tagami K, Uchida S, Shibutani S, Ishida K, Hamamoto T. Soil-soil solution distribution coefficients of global fallout 239Pu and 237Np in Japanese paddy soils. CHEMOSPHERE 2022; 291:132775. [PMID: 34752838 DOI: 10.1016/j.chemosphere.2021.132775] [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: 09/09/2021] [Revised: 10/23/2021] [Accepted: 11/02/2021] [Indexed: 06/13/2023]
Abstract
239Pu and 237Np are long-lived radionuclides that emit alpha rays, and once released into the environment, they are present there for a long period of time. Therefore,239Pu and 237Np are important radionuclides in the safety assessment related to geological disposal of radioactive waste because of the possibility of long-term exposure to humans. Mobilities of these radionuclides in the environment are of particular interest; therefore, in this study, we have made the first-time determination of the soil-soil solution distribution coefficient (Kd, L/kg) using global fallout 239Pu and 237Np in soil. The Kd values were determined by extracting these radionuclides from 23 soil samples using a laboratory batch method. The desorption Kd values of 239Pu were found to vary from 3.2 × 103 to 1.4 × 105 L/kg, and their geometric mean (GM) and arithmetic mean (AM) were 2.3 × 104 L/kg and 3.2 × 104 L/kg, respectively. The desorption Kd values of 237Np ranged from 8.9 × 102 to 2.1 × 104 L/kg, and their GM and AM were 4.1 × 103 L/kg and 6.4 × 103 L/kg, respectively. A comparison between the obtained Kd values of 239Pu and 237Np indicated that the former were about 6-fold higher than the latter in Japanese paddy field soils. Pearson's correlation analysis suggested that the main factors contributing to the sorption and desorption of Pu isotopes in Japanese paddy soils were related to the amounts of Fe and Mn oxides, while the sorption and desorption of 237Np in them would be controlled by an ion-exchange reaction, and/or complex-formation with organic matter, especially in Fluvisols.
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Affiliation(s)
- Jian Zheng
- National Institute of Radiological Sciences, National Institute for Quantum Science and Technology, 4-9-1 Anagawa, Inage, Chiba, 263-8555, Japan.
| | - Keiko Tagami
- National Institute of Radiological Sciences, National Institute for Quantum Science and Technology, 4-9-1 Anagawa, Inage, Chiba, 263-8555, Japan
| | - Shigeo Uchida
- National Institute of Radiological Sciences, National Institute for Quantum Science and Technology, 4-9-1 Anagawa, Inage, Chiba, 263-8555, Japan
| | - Sanae Shibutani
- Nuclear Waste Management Organization of Japan, 4-1-23 Shiba, Minato-ku, Tokyo, 108-0014, Japan
| | - Keisuke Ishida
- Nuclear Waste Management Organization of Japan, 4-1-23 Shiba, Minato-ku, Tokyo, 108-0014, Japan
| | - Takafumi Hamamoto
- Nuclear Waste Management Organization of Japan, 4-1-23 Shiba, Minato-ku, Tokyo, 108-0014, Japan
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Ni Y, Guo Q, Huang Z, Zheng J, Li S, Huang W, Bu W. First study of 237Np in Chinese soils: Source, distribution and mobility in comparison with plutonium isotopes. CHEMOSPHERE 2020; 253:126683. [PMID: 32278920 DOI: 10.1016/j.chemosphere.2020.126683] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Revised: 03/29/2020] [Accepted: 03/31/2020] [Indexed: 06/11/2023]
Abstract
In this study, the distribution and migration of 237Np and 239+240Pu in soils in the vicinity (<5 km) of Qinshan and Tianwan Nuclear Power Plants in China were studied, which is the first specific study of global fallout 237Np in Chinese soils. The 237Np and 239+240Pu concentrations in surface soils showed large spatial inhomogeneity. A remarkable 239+240Pu concentration (4.783 mBq/g) was observed in a surface soil near Qinshan NPP and stands for the ever reported highest value in the Chinese soils. The inventories of 239+240Pu in two Qinshan and Tianwan soil cores were estimated to be 128.8 Bq/m2 and 121.0 Bq/m2, respectively; while the 237Np inventories were 0.039 Bq/m2 and 0.035 Bq/m2 at these sites, respectively. The 240Pu/239Pu atomic ratios in these soils indicated that the global fallout is the main source of Pu in these regions. However, the non-isotopic 237Np/239Pu atomic ratio in environmental soil is not a sensitive indicator for source identification. Furthermore, we conducted pilot study on the migration behaviors of 237Np and 239+240Pu in soil core at Qinshan site with the Convection-Dispersion Equation (CDE) model. The obtained apparent dispersion coefficients of 237Np (2.82 ± 2.06 cm2/y) was 5 times higher than that of 239+240Pu (0.57 ± 0.16 cm2/y), proving that 237Np has stronger migration ability than Pu isotopes in the Qinshan soil. Finally, we predicted that with the increase of migration time, both 237Np and 239+240Pu concentration in the soil will gradually become more evenly distributed among different soil layers due to the dominant dispersion effects.
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Affiliation(s)
- Youyi Ni
- Institute of Nuclear Physics and Chemistry, China Academy of Engineering Physics, Mianyang, 621900, China
| | - Qiuju Guo
- State Key Laboratory of Nuclear Physics and Technology, School of Physics, Peking University, Beijing, 100871, China.
| | - Zhaoya Huang
- Institute of Nuclear Physics and Chemistry, China Academy of Engineering Physics, Mianyang, 621900, China
| | - Jian Zheng
- Center for Advanced Radiation Emergency Medicine, National Institutes for Quantum and Radiological Science and Technology, 4-9-1 Anagawa, Inage, Chiba, 263-8555, Japan.
| | - Sixuan Li
- State Key Laboratory of Nuclear Physics and Technology, School of Physics, Peking University, Beijing, 100871, China
| | - Wenna Huang
- Radiation Monitoring Technical Center of Ministry of Environmental Protection, Hangzhou, 310012, China
| | - Wenting Bu
- Institute of Nuclear Physics and Chemistry, China Academy of Engineering Physics, Mianyang, 621900, China
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Guan Y, Mai J, Xu J, Liu Z. Characteristic of Pu from urban wetland and lacustrine sediments in Suzhou Industrial Park, China. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2020; 213:106134. [PMID: 31983444 DOI: 10.1016/j.jenvrad.2019.106134] [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: 08/24/2019] [Revised: 12/02/2019] [Accepted: 12/09/2019] [Indexed: 06/10/2023]
Abstract
In this study, plutonium activity concentrations in the urban wetlands and lacustrine sediment of Suzhou Industrial Park (SIP) are studied for the first time. Results show 239+240Pu activity concentrations in the wetland surface soils of SIP range from 0.035 to 0.426 mBq/g and the 240Pu/239Pu atom ratio ranges from 0.171±0.024 to 0.226±0.049. Judging from the atom ratio of 240Pu/239Pu, the main source of Pu in the wetland is global fallout. The correlations of Pu between organic matter and heavy metals are also studied. The correlation coefficients show Pu has significant positive correlations with Cu, Sn and Pb but negative correlation with As. Unlike distributions of Pu in other places, Pu in SIP has weak correlation with organic matter content. A sediment core from Lake Yangcheng is also analyzed to investigate the historical record of Pu deposition. The atom ratios of each layer in the sediment core indicate the area is mainly influenced by global fallout. Using Pu as a discrete-time maker, the deposition rate in Lake Yangcheng is 0.396±0.019 cm/yr. The calculated inventory of 239+240Pu is 58.5 Bq/m2, which is in the range of inventories of the corresponding latitudes according to UNSCEAR.
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Affiliation(s)
- Yongjin Guan
- Guangxi Key Laboratory for Relativistic Astrophysics, School of Physical Science and Technology, Guangxi University, Nanning, 530004, China
| | - Jingyu Mai
- Guangxi Key Laboratory for Relativistic Astrophysics, School of Physical Science and Technology, Guangxi University, Nanning, 530004, China; 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
| | - Jiawei Xu
- 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
| | - 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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Igarashi J, Zheng J, Zhang Z, Ninomiya K, Satou Y, Fukuda M, Ni Y, Aono T, Shinohara A. First determination of Pu isotopes ( 239Pu, 240Pu and 241Pu) in radioactive particles derived from Fukushima Daiichi Nuclear Power Plant accident. Sci Rep 2019; 9:11807. [PMID: 31413276 PMCID: PMC6694128 DOI: 10.1038/s41598-019-48210-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2019] [Accepted: 07/25/2019] [Indexed: 11/13/2022] Open
Abstract
Radioactive particles were released into the environment during the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident. Many studies have been conducted to elucidate the chemical composition of released radioactive particles in order to understand their formation process. However, whether radioactive particles contain nuclear fuel radionuclides remains to be investigated. Here, we report the first determination of Pu isotopes in radioactive particles. To determine the Pu isotopes (239Pu, 240Pu and 241Pu) in radioactive particles derived from the FDNPP accident which were free from the influence of global fallout, radiochemical analysis and inductively coupled plasma-mass spectrometry measurements were conducted. Radioactive particles derived from unit 1 and unit 2 or 3 were analyzed. For the radioactive particles derived from unit 1, activities of 239+240Pu and 241Pu were (1.70–7.06) × 10−5 Bq and (4.10–8.10) × 10−3 Bq, respectively and atom ratios of 240Pu/239Pu and 241Pu/239Pu were 0.330–0.415 and 0.162–0.178, respectively. These ratios were consistent with the simulation results from ORIGEN code and measurements from various environmental samples. In contrast, Pu was not detected in the radioactive particles derived from unit 2 or 3. The difference in Pu contents is clear evidence towards different formation processes of radioactive particles, and detailed formation processes can be investigated from Pu analysis.
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Affiliation(s)
- Junya Igarashi
- Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka, 560-0043, Japan.
| | - Jian Zheng
- Department of Radioecology and Fukushima Project, National Institutes for Quantum and Radiological Science and Technology, 491 Anagawa, Inage, Chiba, 263-8555, Japan.
| | - Zijian Zhang
- Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka, 560-0043, Japan
| | - Kazuhiko Ninomiya
- Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka, 560-0043, Japan
| | - Yukihiko Satou
- Collaborative Laboratories for Advanced Decommissioning Science, Japan Atomic Energy Agency, 790-1 Otsuka, Motooka, Tomioka, Futaba, Fukushima, 979-1151, Japan
| | - Miho Fukuda
- Department of Radioecology and Fukushima Project, National Institutes for Quantum and Radiological Science and Technology, 491 Anagawa, Inage, Chiba, 263-8555, Japan
| | - Youyi Ni
- Department of Radioecology and Fukushima Project, National Institutes for Quantum and Radiological Science and Technology, 491 Anagawa, Inage, Chiba, 263-8555, Japan.,State Key Laboratory of Nuclear Physics and Technology, School of Physics, Peking University, Beijing, 100871, China
| | - Tatsuo Aono
- Department of Radioecology and Fukushima Project, National Institutes for Quantum and Radiological Science and Technology, 491 Anagawa, Inage, Chiba, 263-8555, Japan
| | - Atsushi Shinohara
- Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka, 560-0043, Japan
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Huang Z, Ni Y, Wang H, Zheng J, Yamazaki S, Sakaguchi A, Long X, Uchida S. Simultaneous determination of ultra-trace level 237Np and Pu isotopes in soil and sediment samples by SF-ICP-MS with a single column chromatographic separation. Microchem J 2019. [DOI: 10.1016/j.microc.2019.05.044] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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