ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Thallium fractionation in polluted environmental samples using a modified BCR three-step sequential extraction procedure and its determination by electrothermal atomic absorption spectrometry

Ján Medved’, Milan Kališ, Ingrid Hagarová, Peter Matúš, Marek Bujdoš, and Jana Kubová

Geological Institute, Faculty of Natural Sciences, Comenius University in Bratislava, Mlynská dolina 1/G, SK-842 15 Bratislava 4, Slovakia

E-mail: medvedj@fns.uniba.sk

Received: 16 November 2006  Revised: 13 June 2007  Accepted: 10 July 2007

Abstract: Determination of thallium in polluted environmental samples and their extracts obtained by a modified BCR three-step sequential extraction procedure was used to study thallium distribution and mobility in the monitored polluted area affected by acidification (Šobov, Central Slovakia). The results of fractionation applied to 5 soil certified reference materials and 14 environmental samples show that the vast majority of thallium occurred in the residual fraction. This means that highly toxic thallium is strongly entrapped in the parent rock materials remains immobile and its environmental toxicity is therefore reduced. The limit of detection for thallium in the studied fractions was lower than 0.050 mg kg⁻¹, the precision (RSD) of the ultratrace determination of thallium in the studied fractions was better than 17 % and the accuracy of the used method was verified by analyzing certified reference materials.

Keywords: soils - rocks - sediments - thallium - fractionation - sequential extraction - electrothermal atomization - atomic absorption spectrometry

Full paper is available at www.springerlink.com.

DOI: 10.2478/s11696-008-0007-1

Chemical Papers 62 (2) 168–175 (2008)