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

Validation of the Tessier scheme for speciation of metals in soil using the Bland and Altman test

Tiberiu Frentiu, Michaela Ponta, Erika Levei, Emilia Gheorghiu, Iosif Kasler, and Emil A. Cordos

Faculty of Chemistry and Chemical Engineering, Babes-Bolyai University, Arany Janos 11, Cluj-Napoca, Romania

E-mail: ftibi@chem.ubbcluj.ro

Received: 29 March 2007  Revised: 23 July 2007  Accepted: 2 August 2007

Abstract: The Tessier extraction method was used for speciation of Cu, Pb, Zn, As, Fe and Mn in a large concentration range in contaminated soil with various mineralogical compositions. The results were compared by X-ray fluorescence spectrometry (XRF) as a reference method using the Bland and Altman test. A sum of five fractions (exchangeable, bound to carbonates, Fe-Mn oxides, organic matter and residual forms) was compared with the total content determined on solid matrix by the reference method. A good agreement between the methods in the whole concentration range was found for Cu, Zn, As, and Fe. For Mn and Pb, XRF was found suitable to verify the sequential extraction only for concentrations above 250 mg kg⁻¹. This was a consequence of a poorer reproducibility of Pb extraction using the Tessier scheme due to a great difference in the mineralogical composition and the diversity of the Pb species identified in soil. The poorer result of Mn was attributed to the spectral interference of Fe in XRF.

Keywords: Tessier scheme - Bland and Altman test - soil analysis - metal fractionation

Full paper is available at www.springerlink.com.

DOI: 10.2478/s11696-007-0087-3

Chemical Papers 62 (1) 114–122 (2008)