The occurrence and speciation of arsenic, antimony, and selenium in ground water of Poznan city (Poland)

This paper presents results of determination of total arsenic, antimony, and selenium contents as well as their species in ground water from the region of Poznan. Determinations were carried by means of atomic absorption spectrometry hyphenated with generation of hydrides and in situ preconcentration in a graphite tube (HG-GFAAS). In order to obtain the best efficiency of an analyte concentration process on the walls of the tube, palladium was used as a modifying agent. The concentration of total arsenic was up to 2.04 ng ml(-1), that of antimony up to 0.71 ng ml(-1), and that of selenium up to 0.44 ng ml-1. The lowest concentrations of the investigated elements in ground water and the predominance of As(III), Sb(III), and Se(IV) speciation forms over As(V), Sb(V), and Se(VI) forms were found in the region, where the thickest aquitards (glacial tills of the Vistulian Glaciation) overlay an aquifer. Moreover, the geological and hydrogeological conditions of the study area are presented.