title: Radiostrontium monitoring of bivalves from the Pacific coast of eastern Japan.
abstract: In early April 2011, radiostrontium was accidentally released from the Fukushima Daiichi Nuclear Power Plant to the Pacific coast of eastern Japan. We developed a simple procedure to analyze radiostrontium levels in marine mussels (Septifer virgatus) and seawater using crown ether (Sr Resin; Eichrom). Then, we used our method to describe the spatial and temporal distribution of radiostrontium in mussels and seawater on the Pacific coast of eastern Japan from 2011 to 2013 and for 2015. Activity of (90)Sr in mussels and seawater decreased with distance from the Fukushima Daiichi Nuclear Power Plant and between 2011 and 2013 tended to be higher in areas south of the Fukushima Daiichi Nuclear Power Plant than to the north of it. Activity in mussels and seawater also tended to decrease from 2011 to 2013 and by 2015 had reached levels experienced prior to the Fukushima accident. Our results suggest that radiostrontium discharged from the Fukushima Daiichi Nuclear Power Plant was dispersed by coastal currents in a southerly direction along the Pacific coast of eastern Japan from 2011 to 2013, following which its activity decreased to background levels by 2015.
authors.affiliation: National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki, 305-8506, Japan. zinichi.karube.sri@vc.ibaraki.ac.jp.|Present Address: Center for Water Environment Studies, Ibaraki University, 1375 Ohu, Itako, Ibaraki, 311-2402, Japan. zinichi.karube.sri@vc.ibaraki.ac.jp.
authors.forename: Zin'ichi
authors.initials: Z
authors.lastname: Karube
authors.affiliation: National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki, 305-8506, Japan.
authors.forename: Yoko
authors.initials: Y
authors.lastname: Inuzuka
authors.affiliation: National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki, 305-8506, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Tanaka
authors.affiliation: Tsukuba Branch, WDB Co. Ltd., 1-6-1 Takezono, Tsukuba, Ibaraki, 305-0032, Japan.
authors.forename: Katsuaki
authors.initials: K
authors.lastname: Kurishima
authors.affiliation: Institute for Agro-Environmental Sciences, NARO, 3-1-3 Kannondai, Tsukuba, Ibaraki, 305-8604, Japan.
authors.forename: Nobuharu
authors.initials: N
authors.lastname: Kihou
authors.affiliation: National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki, 305-8506, Japan.
authors.forename: Yasuyuki
authors.initials: Y
authors.lastname: Shibata
mesh_terms: D000818:Animals; D049872:Bivalvia / Q000737:chemistry*; D062406:Fukushima Nuclear Accident; D007564:Japan; D010140:Pacific Ocean; D011834:Radiation Monitoring; D012623:Seawater; D013326:Strontium Radioisotopes / Q000032:analysis*; D014875:Water Pollutants, Radioactive / Q000032:analysis*
chemical_list: D013326:Strontium Radioisotopes; D014875:Water Pollutants, Radioactive
keywords: Crown ether; Eastern Japan; Fukushima accident; Mussels; Pacific coast; Radionuclide; Strontium