A study of the analytical parameters important for the sequential extraction procedure using microwave heating for Pb, Zn and Cu in calcareous soils Original Research Article

A four-step microwave extraction procedure, using microwave heating, for Pb, Zn and Cu fractionation has been elaborated for calcareous soils. This procedure distinguishes the metal fraction bound to carbonate, to iron and manganese oxides, to organic matter and the residual fraction. Sample and analytical variances have been estimated to identify the anomalous metal contents in the light of the variation in the concentration among the samples. Performances of each step of the method have also been calculated. The validity of the method was verified by a mass balance using calcareous soils and two certified reference materials. The results obtained were appropriate for the assessment of the environmental risks.