Development of a sequential extraction scheme for As in soils and subsequent detection with ICP-MS.

Based on the existing extraction schemes for heavy metals (Zeien and Bruemmer) and phosphorous (Chang and Jackson) in soil samples an extraction scheme is to be optimized in the way that readsorption and coprecipitation of As is minimized, that the maximum amount of As can be found in the corresponding phases of the extraction scheme. The scheme is then to be tested on standardsoils in the laboratory and on artificial soils containing single phases, that the quality of the procedure can be proofed directly. The results are of main importance for environmental studies, since the influence of 'available' As is quite different to the total As concentration in soil samples.