Determination of inorganic arsenic in soil with microwave assisted extraction coupled with hydride generation-atomic fluorescence spectrometry

Inorganic arsenic in soil was extracted by microwave assisted extraction(MAE) and determined by HG-AFS.The MAE operating conditions were optimized by the orthogonal test design combined with the mono-factor test.The interference which is from concomitant ions on inorganic arsenic has been eliminated by adding ascorbicacid-thiourea-citricacid.The linear range of the calibration curve for inorganic arsenic was 1.0～160.0 μg/L.The detection limit was 0.20 μg/L and the RSD was 0.3%.The recoveries of inorganic arsenic in soil samples were 93.0%～98.5%.The method was successfully applied to the extraction and determination of inorganic arsenic in soil samples from different regions.