Determination of arsenic in sediment and soil slurries by electrothermal atomic absorption spectrometry using W-Rh permanent modifier

A simple method is described for the determination of As in sediments and s oils by electrothermal atomic absorption spectrometry (ETAAS). The procedur e combines slurry sampling ETAAS with a 250 mug W + 200 mug Rh permanent ch emical modifier. Slurries were sonicated for 20 s before being delivered to the previously W-Rh treated platform. The detection limit for 0.50% m/v sl urries was 0.4 mug g(-1). The RSD for 783 consecutive measurements of 20 mu l of 0.50% m/v soil-5 slurry was 3.8%. In order to verify the accuracy and precision of the proposed method, five sediment and two soil certified refe rence materials were analysed and the results obtained were in agreement wi th the certified values.