Determination of traces of chromium in foods by solvent extraction flame atomic absorption spectrometry.

ABSTRACT A simple methodology for Cr(III) determination in foods was developed through flame atomic absorption spectrometry with air/acetylene after a fast oxidation of Cr(III) with KMnO4 and pre-concentration of Cr(VI) in MIK as CrO2CI2. A limit of detection and limit of quantification (LOQ), respectively, of 4 μg/Kg and 13 μg/Kg Cr(III) were obtained in commercialized foods in Sao Paulo, Brazil. Two certificated samples as well as some food samples were analyzed with good results. A study of sample treatment showed that the dry ash method is the best.