A microwave oven digestion procedure was developed for rapid dissolution of sludge samples (NIST SRM 2781) for the determination of As and Se. Microwave oven digestion with HNO3 and H2SO4 provides results comparable to those obtained by reflux column digestion using HNO3, H2SO4 and HClO4. The experimental details for sample preparation and the flow injection hydride generation atomic absorption spectrometric method are discussed. The effects of matrix and various acid concentrations on the extraction and absorbance were also studied. The proposed method has detection limits of 0.15 and 0.17 ng ml–1 for As and Se, respectively.
