Determination of arsenic and selenium in spinach and tomato leaves reference materials using flow injection and atomic absorption spectrometry

A flow-injection atomic absorption spectrometric method was developed for the determination of trace amounts of arsenic and selenium in proposed spinach and tomato leaves standard reference materials (SRM 1570a and SRM 1573a). The samples were digested with HNO(3), H(2)SO(4) and HClO(4) using reflux column. The experimental details for sample preparation and the flow injection hydride generation method are discussed. The effect of matrix and various acid concentrations on the extraction and absorbance was also studied. The method has detection limits of 0. 15 ng As/ml and 0.17 ng Se/ml. Standard Reference Materials (SRM 1571 and 1547) were analyzed and the results agreed well with the certified values.