title: Determination of strontium-90 from direct separation of yttrium-90 by solid phase extraction using DGA Resin for seawater monitoring.
abstract: It is important for public safety to monitor strontium-90 in aquatic environments in the vicinity of nuclear related facilities. Strontium-90 concentrations in seawater exceeding the background level have been observed in accidents of nuclear facilities. However, the analytical procedure for measuring strontium-90 in seawater is highly demanding. Here we show a simple and high throughput analytical technique for the determination of strontium-90 in seawater samples using a direct yttrium-90 separation. The DGA Resin is used to determine the abundance of strontium-90 by detecting yttrium-90 decay (beta-emission) in secular equilibrium. The DGA Resin can selectively collect yttrium-90 and remove naturally occurring radionuclides such as (40)K, (210)Pb, (214)Bi, (238)U, and (232)Th and anthropogenic radionuclides such as (140)Ba, and (140)La. Through a sample separation procedure, a high chemical yield of yttrium-90 was achieved at 95.5±2.3%. The result of IAEA-443 certified seawater analysis (107.7±3.4 mBq kg(-1)) was in good agreement with the certified value (110±5 mBq kg(-1)). By developed method, we can finish analyzing 8 samples per day after achieving secular equilibrium, which is a reasonably fast throughput in actual seawater monitoring. By processing 3 L of seawater sample and applying a counting time of 20 h, minimum detectable activity can be as low as 1.5 mBq kg(-1), which could be applied to monitoring for the contaminated marine environment. Reproducibility was found to be 3.4% according to 10 independent analyses of natural seawater samples from the vicinity of the Fukushima Daiichi Nuclear Power Plant in September 2013.
authors.affiliation: Department of Radiation Chemistry, Institute of Radiation Emergency Medicine, Hirosaki University, 66-1 Hon-cho, Hirosaki, Aomori 036-8564, Japan. Electronic address: tazoe@hirosaki-u.ac.jp.
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Tazoe
authors.affiliation: Atmosphere and Ocean Research Institute, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa-shi, Chiba 277-8564, Japan.
authors.forename: Hajime
authors.initials: H
authors.lastname: Obata
authors.affiliation: College of Humanities and Sciences, Nihon University, 3-25-40, Sakurajosui, Setagayaku, Tokyo 156-8550, Japan.
authors.forename: Takeyasu
authors.initials: T
authors.lastname: Yamagata
authors.affiliation: Center for Water Environment Studies, Ibaraki University, 1375, Ohu, Itako, Ibaraki 311-2402, Japan.
authors.forename: Zin'ichi
authors.initials: Z
authors.lastname: Karube
authors.affiliation: College of Humanities and Sciences, Nihon University, 3-25-40, Sakurajosui, Setagayaku, Tokyo 156-8550, Japan.
authors.forename: Hisao
authors.initials: H
authors.lastname: Nagai
authors.affiliation: Department of Radiation Chemistry, Institute of Radiation Emergency Medicine, Hirosaki University, 66-1 Hon-cho, Hirosaki, Aomori 036-8564, Japan.
authors.forename: Masatoshi
authors.initials: M
authors.lastname: Yamada
mesh_terms: D007700:Kinetics; D057230:Limit of Detection; D015203:Reproducibility of Results; D012116:Resins, Plant / Q000737:chemistry; D012623:Seawater; D052616:Solid Phase Extraction / Q000379:methods*; D013324:Strontium / Q000302:isolation & purification*; D013326:Strontium Radioisotopes; D014875:Water Pollutants, Radioactive / Q000302:isolation & purification*; D015019:Yttrium / Q000302:isolation & purification*; D015021:Yttrium Radioisotopes
chemical_list: D012116:Resins, Plant; D013326:Strontium Radioisotopes; D014875:Water Pollutants, Radioactive; D015021:Yttrium Radioisotopes; D015019:Yttrium; D013324:Strontium