A Comparison Between Sediment Fractions, Obtained from Sequential Extraction and Estimated from Single Extractions

Abstract

We compared the sequential extraction according to Tessier et al. with the results, obtained from single extractions employing reagents and reacting conditions similar to these of the different Tessier steps. The aim was to investigate whether an approach involving fewer consecutive steps provides similar information as sequential extraction.

The estimates of the exchangeable, acid extractable and reducible fractions from the single extraction data were in good agreement with the fractions obtained using sequential extraction. The oxidizable fraction should be determined by extraction of the residue of a hydroxylamine-hydrochloride extraction.

Key Words:

• Heavy metals
• sequential extraction
• fractionation
• speciation
• sediment