Chemical speciation of antimony in marine algae

Abstract

An atomic absorption‐hydride generation technique was devised with an air/hydrogen flame system for determination of the speciation of antimony(III) and antimony(V) in marine algae. Antimony(III) is determined selectively at pH 4, total antimony after low temperature ashing of the dry algae using electrically excited oxygen atoms. Detection limits are 0.05 ng ± 10%. For the three marine algae ( Ulva sp., Enteromorpha sp., and Sargassum sp.) sampled in San Diego Bay (California) seawater, Sb(V) is dominant. However, Sargassum sp. can contain up to 30% of Sb(III), showing an ability to form reduced compounds and therefore a possible role in the cycling of antimony in coastal waters.