Determination of As in Vegetable Oil and Biodiesel by Graphite Furnace Atomic Absorption Spectrometry

In this work, an alternative procedure for the determination of As in vegetable oils and biodiesel of different origins by graphite furnace atomic absorption spectrometry (GFAAS) is proposed. The sample stabilization was achieved by the formation of three component solutions prepared mixing the samples with appropriate volumes of propan-1-ol and nitric acid. Palladium Was used as a chemical modifier. Pyrolysis and atomization temperatures as well as the sample dilution factor were investigated and optimized, Because no adequate certified reference material was available, accuracy was assessed by recovery tests, using both organic and inorganic species. Recoveries ranged from 95 to 110%. The limit of detection in the original sample was 0.3 mg kg(-1), which is adequate for the analysis of vegetable oils and biodiesel, according to the expected Brazilian legislation.