title: Natural variation of ambient dose rate in the air of Izu-Oshima Island after the Fukushima Daiichi Nuclear Power Plant accident.
abstract: The ambient dose rate in air and radioactivity concentration in soil samples collected on Izu-Oshima Island were observed in 2012, 2013 and 2014, i.e. 1, 2 and 3 years after the severe accident at the Fukushima Daiichi Nuclear Power Plant. A car-borne survey for the ambient dose rate in air was carried out for the entire island. Soil samples were collected for the radioactivity concentration measurements from 22 points. The ambient dose rates in air were 36 nGy h(-1) in 2012, 34 nGy h(-1) in 2013 and 29 nGy h(-1) in 2014. The corresponding radioactivity concentrations in those years for (134)Cs were 53, 39 and 29 Bq kg(-1) and for (137)Cs, 87, 73 and 75 Bq kg(-1). All the values have decreased every year.
authors.affiliation: Department of Radiological Sciences, Tokyo Metropolitan University, 7-2-10 Higashiogu, Arakawa-ku, Tokyo 116-8551, Japan.
authors.forename: Fumihiko
authors.initials: F
authors.lastname: Maedera
authors.affiliation: Department of Radiological Sciences, Tokyo Metropolitan University, 7-2-10 Higashiogu, Arakawa-ku, Tokyo 116-8551, Japan.
authors.forename: Kazumasa
authors.initials: K
authors.lastname: Inoue
authors.affiliation: Gunma Prefectural College of Health Sciences, 323-1 Kamioki-machi, Maebashi-shi, Gunma 371-0052, Japan.
authors.forename: Masato
authors.initials: M
authors.lastname: Sugino
authors.affiliation: Department of Radiological Sciences, Tokyo Metropolitan University, 7-2-10 Higashiogu, Arakawa-ku, Tokyo 116-8551, Japan.
authors.forename: Ryosuke
authors.initials: R
authors.lastname: Sano
authors.affiliation: Department of Radiological Sciences, Tokyo Metropolitan University, 7-2-10 Higashiogu, Arakawa-ku, Tokyo 116-8551, Japan.
authors.forename: Mai
authors.initials: M
authors.lastname: Furue
authors.affiliation: Department of Radiological Sciences, Tokyo Metropolitan University, 7-2-10 Higashiogu, Arakawa-ku, Tokyo 116-8551, Japan.
authors.forename: Hideo
authors.initials: H
authors.lastname: Shimizu
authors.affiliation: Department of Radiological Sciences, Tokyo Metropolitan University, 7-2-10 Higashiogu, Arakawa-ku, Tokyo 116-8551, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Tsuruoka
authors.affiliation: Department of Radiological Sciences, Tokyo Metropolitan University, 7-2-10 Higashiogu, Arakawa-ku, Tokyo 116-8551, Japan.
authors.forename: Tan
authors.initials: T
authors.lastname: Le Van
authors.affiliation: Department of Radiological Sciences, Tokyo Metropolitan University, 7-2-10 Higashiogu, Arakawa-ku, Tokyo 116-8551, Japan fukushi@tmu.ac.jp.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Fukushi
mesh_terms: D000396:Air Pollutants, Radioactive / Q000032:analysis*; D002250:Carbon Radioisotopes / Q000032:analysis*; D002588:Cesium Radioisotopes / Q000032:analysis*; D062406:Fukushima Nuclear Accident; D006801:Humans; D062312:Islands; D007564:Japan; D055848:Nuclear Power Plants; D011834:Radiation Monitoring / Q000379:methods*
chemical_list: D000396:Air Pollutants, Radioactive; D002250:Carbon Radioisotopes; D002588:Cesium Radioisotopes