Okamoto K
National Institute for Environmental Studies, Ibaraki, Japan.
Sci Total Environ. 1991 Sep;107:29-44. doi: 10.1016/0048-9697(91)90248-d.
Rice flour-unpolished reference material was prepared from unpolished rice collected from three locations in Japan. This reference material is certified for elemental composition and consists of three samples containing low-level (0.023 microgram/g), medium-level (0.32 microgram/g) and high-level (1.82 micrograms/g) of Cd. The unpolished rice was pulverized, oven-dried, homogenized and finally packaged into 1000 glass bottles. The prepared material satisfied the homogeneity criteria for a reference material. Collaborative analytical studies on the elemental composition of the rice flour-unpolished reference material were conducted using various analytical techniques which lead to the certification. Stable isotope dilution/ICP-MS was successfully applied to the accurate determination of Cu, Zn, Mo and Cd in the reference material. Certified values are provided for Ca, Cd, Cu, Fe, K, Mg, Mn, Mo, Na, Ni, P, Rb and Zn, based on results of determinations by at least three independent analytical techniques. Reference values are reported for Al, As, Br, Cl, Co, Cr, Hg, Se and Sr. The elemental compositions of the three rice flour-unpolished samples are very similar, except for Cd, and are considered typical of Japanese unpolished rice.
糙米粉参考物质由从日本三个地点采集的糙米制备而成。该参考物质经过元素组成认证，由三个分别含有低水平（0.023微克/克）、中等水平（0.32微克/克）和高水平（1.82微克/克）镉的样品组成。糙米经粉碎、烘干、均质化处理，最终装入1000个玻璃瓶中。制备的物质满足参考物质的均匀性标准。使用各种分析技术对糙米粉参考物质的元素组成进行了协同分析研究，从而得出认证结果。稳定同位素稀释/电感耦合等离子体质谱法成功应用于参考物质中铜、锌、钼和镉的准确测定。基于至少三种独立分析技术的测定结果，给出了钙、镉、铜、铁、钾、镁、锰、钼、钠、镍、磷、铷和锌的认证值。报告了铝、砷、溴、氯、钴、铬、汞、硒和锶的参考值。除镉外，三个糙米粉样品的元素组成非常相似，被认为是日本糙米的典型组成。
