title: Characterization of brown rice as a certified reference material for Fukushima accident-related radioactivity measurements.
abstract: We developed a certified reference material of brown rice to measure radioactivity from the Fukushima Daiichi Nuclear Power Plant accident. The rice was planted in the spring of 2011, just after the Fukushima accident occurred, and it was harvested in the autumn of 2011. The certified value of radioactivity concentration in the rice was 33.6 Bq kg(-1) of Cs-134 and 51.8 Bq kg(-1) of Cs-137 on August 1, 2012. The reference material is being widely distributed by the National Metrology Institute of Japan. To determine the radioactivity and its uncertainties in the brown rice, we employed gamma-ray spectrometry with a high-purity germanium detector and Monte Carlo simulation.
authors.affiliation: National Metrology Institute of Japan, Japan; The Graduate University for Advanced Studies (Sokendai), Japan. Electronic address: y.unno@aist.go.jp.
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Unno
authors.affiliation: National Food Research Institute, Japan.
authors.forename: Mayumi
authors.initials: M
authors.lastname: Hachinohe
authors.affiliation: National Food Research Institute, Japan.
authors.forename: Shioka
authors.initials: S
authors.lastname: Hamamatsu
authors.affiliation: National Food Research Institute, Japan.
authors.forename: Setsuko
authors.initials: S
authors.lastname: Todoriki
authors.affiliation: National Metrology Institute of Japan, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Yunoki
authors.affiliation: National Metrology Institute of Japan, Japan.
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Miura
mesh_terms: D062406:Fukushima Nuclear Accident; D007564:Japan; D012275:Oryza; D011834:Radiation Monitoring / Q000379:methods*; D011848:Radioactive Pollutants / Q000032:analysis*; D012015:Reference Standards
chemical_list: D011848:Radioactive Pollutants
keywords: Brown rice; Certified reference material; Cs-134; Cs-137; Fukushima Daiichi Nuclear Power Plant accident; Gamma-ray spectrometry