title: Determination method for total arsenic and partial-digestion method with nitric acid for inorganic arsenic speciation in several varieties of rice.
abstract: The determination method of total arsenic (As) and the speciation method of inorganic As for non-glutinous rice reported in our preceding paper were applied to several varieties of rice under optimized experimental conditions. In the determination of total As with ICP-MS, acetic acid was added to increase the sensitivity and an internal reference method with germanium was adopted to increase the precision. The extraction temperature in the partial-digestion method with nitric acid to speciate inorganic As was raised to 100 degrees C, because extraction efficiency over 90% was obtained from glutinous rice and colored rice at this temperature. In the investigation of polished and unpolished forms of non-glutinous, glutinous, and colored rice, the amounts of total and inorganic As were 0.04-0.54 mg/kg and 0.02-0.41 mg/kg, respectively. The color of rice was not related to total or inorganic As content. These results indicate that the inorganic As content in commercial rice should be carefully monitored.
authors.affiliation: Japan Food Research Laboratories, Shizuoka, Japan.
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Nishimura
authors.forename: Megumi
authors.initials: M
authors.lastname: Hamano-Nagaoka
authors.forename: Naoki
authors.initials: N
authors.lastname: Sakakibara
authors.forename: Takashi
authors.initials: T
authors.lastname: Abe
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Maekawa
authors.forename: Tamio
authors.initials: T
authors.lastname: Maitani
mesh_terms: D019342:Acetic Acid / Q000494:pharmacology; D001151:Arsenic / Q000032:analysis*; D002851:Chromatography, High Pressure Liquid; D005506:Food Contamination / Q000032:analysis; D005857:Germanium / Q000494:pharmacology; D013058:Mass Spectrometry; D017942:Nitric Acid / Q000494:pharmacology*; D012275:Oryza / Q000737:chemistry*
chemical_list: D005857:Germanium; D017942:Nitric Acid; D001151:Arsenic; D019342:Acetic Acid