title: Determination of plutonium and its isotopic ratio in marine sediment samples using quadrupole ICP-MS with the shield torch system under normal plasma conditions.
abstract: An analytical method for determining (239)Pu and (240)Pu in marine sediment samples, which uses quadrupole ICP-MS, was developed in this work. A simple anion-exchange chromatography system was employed for the separation and purification of Pu from the sample matrix. A sufficient decontamination factor of 1.4 x 10(4) for U, which interferes with the determination of (239)Pu, was achieved. High sensitivity Pu determination was obtained, which led to an extremely low concentration detection limit of approximately 8 fg/ml (0.019 mBq/ml for (239)Pu; 0.071 mBq/ml for (240)Pu) in a sample solution, or an absolute detection limit of 42 fg in a 5 ml sample solution, by using the shield torch technique. Analytical results for the determination of the (239+240)Pu and the (240)Pu/(239)Pu ratio in IAEA 368 (ocean sediment) reference material indicated that the accuracy of the method was satisfactory. The method developed was successfully applied to a study of Pu behavior in the sediments from Sagami Bay, Japan. The observed high (240)Pu/(239)Pu ratio in the sediment core indicated that there was additional Pu input derived from close-in fallout in addition to the global fallout.
authors.affiliation: Nakaminato Laboratory for Marine Radioecology, National Institute of Radiological Sciences, 3609 Isozaki-cho, Hitachinaka, 311-1202 Ibaraki, Japan. jzheng@nirs.go.jp
authors.forename: Jian
authors.initials: J
authors.lastname: Zheng
authors.forename: Masatoshi
authors.initials: M
authors.lastname: Yamada
authors.forename: Zhongliang
authors.initials: Z
authors.lastname: Wang
authors.forename: Tatsuo
authors.initials: T
authors.lastname: Aono
authors.forename: Masashi
authors.initials: M
authors.lastname: Kusakabe
mesh_terms: D004784:Environmental Monitoring / Q000379:methods*; D019015:Geologic Sediments / Q000737:chemistry*; D007564:Japan; D011005:Plutonium / Q000032:analysis*; D011868:Radioisotopes; D013054:Spectrophotometry, Atomic / Q000379:methods*; D014875:Water Pollutants, Radioactive / Q000032:analysis*
chemical_list: D011868:Radioisotopes; D014875:Water Pollutants, Radioactive; D011005:Plutonium