title: Sensitive determination of cadmium in brown rice and spinach by flame atomic absorption spectrometry with solid-phase extraction.
abstract: A sensitive flame atomic absorption spectrometry (FAAS) method was developed for the determination of cadmium (Cd) in brown rice and spinach. The method involves extraction with 1 M hydrochloric acid (HCl), followed by a selective pre-concentration by solid-phase extraction (SPE). The pH of the loading sample solution was adjusted to 4.0 for the brown rice and to 5.0 for the spinach. The masking agents, tartrate and citrate, were required for the spinach before pH adjustment. The SPE step achieved a 20-fold enrichment of the sample solution. The limits of quantification (LOQs) were 0.0054 mg kg⁻¹ for the brown rice and 0.0022 mg kg⁻¹ for the spinach, being more sensitive than those of AOAC Official method 999.10. A single-laboratory validation was performed by testing spiked samples at 0.04 and 0.08 mg kg⁻¹ for the brown rice, and 0.02 and 0.04 mg kg⁻¹ for the spinach. The average recoveries were 93.3-96.9% with relative standard deviations (RSDs) of 4.1-8.2% for brown rice, and 90.5-91.9% with RSDs of 5.8-10.0% for spinach.
authors: Hyogo Prefectural Institute of Public Health and Consumer Sciences, 2-1-29 Arata-cho, Hyogo-ku, Kobe 652-0032, Japan. shigeki_akamatsu@pref.hyogo.lg.jp
authors: Shigeki
authors: S
authors: Akamatsu
authors: Naoki
authors: N
authors: Yoshioka
authors: Takao
authors: T
authors: Mitsuhashi
mesh_terms: D002104:Cadmium / Q000032:analysis* / Q000737:chemistry / Q000302:isolation & purification; D002614:Chelating Agents / Q000737:chemistry; D019343:Citric Acid / Q000737:chemistry; D004785:Environmental Pollutants / Q000032:analysis* / Q000737:chemistry / Q000302:isolation & purification; D005506:Food Contamination; D005513:Food Inspection / Q000379:methods; D006863:Hydrogen-Ion Concentration; D007098:Imino Acids / Q000737:chemistry; D007202:Indicators and Reagents / Q000737:chemistry; D007564:Japan; D057230:Limit of Detection; D012275:Oryza / Q000737:chemistry*; D018515:Plant Leaves / Q000737:chemistry*; D015203:Reproducibility of Results; D012639:Seeds / Q000737:chemistry*; D052616:Solid Phase Extraction; D013054:Spectrophotometry, Atomic; D018724:Spinacia oleracea / Q000737:chemistry*; D013644:Tartrates / Q000737:chemistry
chemical_list: D002614:Chelating Agents; D004785:Environmental Pollutants; D007098:Imino Acids; D007202:Indicators and Reagents; D013644:Tartrates; D002104:Cadmium; D019343:Citric Acid; C029768:tartaric acid; C008109:iminodiacetic acid