title: Determination of lead in rice grains by solid sampling HR-CS GFAAS.
abstract: A study was performed for the determination of lead in rice grains directly by solid sampling high resolution continuum source graphite furnace atomic absorption spectrometry (HR-CS GFAAS) without digesting sample. The effects of sample amount, pyrolysis/atomization temperatures on the determination of lead in rice were investigated and optimized using a certificated rice flour. The lead concentrations were determined applying 800 °C of pyrolysis and 1800 °C of atomization temperatures without modifier. LOD (N=10, 3σ) and characteristic mass were 2.3 μg kg(-1) and 8.1 pg, respectively. The certified lead value of a rice flour CRM was found in its uncertainity limits. The lead contents of various rice samples obtained from markets in Turkey were between 0.009 and 0.162 mg kg(-1) which are in acceptable range. The average lead concentrations in various rice grains taken from the same package were significantly different from each other.
authors.affiliation: Istanbul Technical University, Faculty of Science and Letters, Department of Chemistry, Maslak, 34469 Istanbul, Turkey.
authors.forename: Sema
authors.initials: S
authors.lastname: Gunduz
authors.forename: Suleyman
authors.initials: S
authors.lastname: Akman
mesh_terms: D005506:Food Contamination / Q000032:analysis; D007854:Lead / Q000032:analysis*; D012275:Oryza / Q000737:chemistry*; D012639:Seeds / Q000737:chemistry; D013054:Spectrophotometry, Atomic / Q000295:instrumentation / Q000379:methods*
chemical_list: D007854:Lead
keywords: High-resolution continuum source atomic absorption spectrometry; Lead; Microscale distribution; Rice; Solid sampling