Chromium redox speciation in food samples

Abstract

Chromium is an element with important biological characteristics, depending on its different species. Cr(III)is considered as essential; however, the Cr(VI) form is classi ed as carcinogenic. For this reason, speciation analysisin food samples is a very important question.The proposed data procedures for chromium redox speciation in theliterature can be divided into those with the use of online hyphenated techniques and those where appropriate samplepretreatment is necessary. The strategies for nonchromatographic speciation are mainly based on selective liquid{liquidextraction procedures, coprecipitation, selective separation of chromium species using a solid phase extraction column,or complexation reactions.In this paper, the application of these strategies for determination of Cr(III) and Cr(VI)contents in common food samples (water, milk, tea infusion, bread, and beer) are presented and discussed. This surveyis an attempt to cover the state of the art since 2012.