Direct spectrophotometric method for the determination of hydrochloric acid-releasable arsenic in sediments and soils

Abstract

A spectrophotometric method for the direct determination of hydrochloric acid-releasable inorganic arsenic has been developed and applied successfully to the quantitative evaluation of arsenic in soil and sediment samples. The method provides reliable data on the quantitative recovery of 2.0 µg of arsenic(V) added to 5.0 g (0.4 mg kg^–1) of soil, clay, sand and sediment samples. The method is simple, reliable and relatively rapid; 24 samples can be analysed in about 1 h. It does not require elaborate equipment and can be routinely used for the quantitative determination of arsenic in soil and soil-like material. The detection limit has been established as 0.5 µg of arsenic. The extent of ionic interference in the use of this method for arsenic determination in soil has also been quantitatively evaluated.