title: Development of a certified reference material (NMIJ CRM 7531-a) for the determination of trace cadmium and other elements in brown rice flour.
abstract: A certified reference material (CRM) for trace cadmium and other elements in brown rice flour was developed at the National Metrology Institute of Japan (NMIJ).  The CRM was provided as a dry powder after drying and frozen pulverization of fresh brown rice obtained from a Japanese domestic market.  Characterization of the property value for each element was carried out exclusively by NMIJ with at least two independent analytical methods, including inductively coupled plasma mass spectrometry (ICP-MS), ICP high-resolution mass spectrometry, isotope-dilution ICP-MS, ICP optical emission spectrometry, and graphite-furnace atomic-absorption spectrometry.  Property values were provided for six elements (Mn, Fe, Cu, Zn, As, and Cd).  The concentration range of the property values was from 0.280 mg kg(-1) of As to 31.8 mg kg(-1) of Zn.  The combined relative standard uncertainties of the property values were estimated by considering the uncertainties of the homogeneity, characterization, difference among analytical methods, dry-mass correction factor, and calibration standard.  The range of the relative combined standard uncertainties was from 1.1% of Zn to 1.6% of As.
authors.affiliation: Environmental Standards Section, National Metrology Institute of Japan, National Institute of Advanced Industrial Science and Technology, Tsukuba, Ibaraki 305–8563, Japan. shinichi-miyashita@aist.go.jp
authors.forename: Shin-ichi
authors.initials: S
authors.lastname: Miyashita
authors.forename: Kazumi
authors.initials: K
authors.lastname: Inagaki
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Narukawa
authors.forename: Yanbei
authors.initials: Y
authors.lastname: Zhu
authors.forename: Takayoshi
authors.initials: T
authors.lastname: Kuroiwa
authors.forename: Akiharu
authors.initials: A
authors.lastname: Hioki
authors.forename: Koichi
authors.initials: K
authors.lastname: Chiba
mesh_terms: D001151:Arsenic / Q000032:analysis / Q000592:standards; D002104:Cadmium / Q000032:analysis* / Q000592:standards; D002138:Calibration; D003300:Copper / Q000032:analysis / Q000592:standards; D005433:Flour / Q000032:analysis* / Q000592:standards; D007501:Iron / Q000032:analysis / Q000592:standards; D008345:Manganese / Q000032:analysis / Q000592:standards; D013058:Mass Spectrometry; D012275:Oryza / Q000737:chemistry*; D015032:Zinc / Q000032:analysis / Q000592:standards
chemical_list: D002104:Cadmium; D008345:Manganese; D003300:Copper; D007501:Iron; D015032:Zinc; D001151:Arsenic