Automated procedure for the determination of soluble arsenic using hydride generation atomic-absorption spectroscopy

Abstract

An automated procedure for the determination of soluble arsenic, using hydride generation atomic-absorption spectroscopy, is described and optimised operating conditions are derived. Interferences are observed in the presence of silver(I), gold(III), iron(III), platinum(IV), antimony(III), strontium(II), fluoride and sulphide but can be overcome by suitable pretreatment procedures. The detection limit (based on twice the standard deviation for 15 blank measurements) is 0.90 ng ml–1 of arsenic for arsenic(III), arsenic(V) and methylarsenic species. A 10% negative bias of results is observed in the determination of dimethylarsenic species.