Evaluation of Anthropogenic Impacts on Soiland Regolith Materials Based on BCR Sequential Extraction Analysis

Abstract

This study was conducted in Assaluyeh region, southwest of Iran to show utilization and efficiency of sequential extraction analysis in environmental impact studies using soil and related regolith materials as sample media. In order to investigate distribution of heavy metals, optimized BCR (Community Bureau of Reference) sequential extraction analysis method was used. In this caseeight representative samples which state all types of different regolith materials in the area were investigated. Total concentration and chemical partitioning of a number of elements (Pb, Cu, Zn, Cr, Mn and Fe) were studied to cover all spectral from typical anthropogenic elements, lead and copper, elements of assumed mixed origin, chromium and zinc, to mostly lithogenic elements, iron and manganese. Results stated that the concentrations of each chemical phase extracted from samples are below the total concentration of each element.The results could be used to establish best media indicators for environmental studies with dependence on type of elements determined in regolith material. Using sequential extraction analysis, the association of particular elements with geochemical phases in soils and related materials was investigated as well asthe importance of particular phases in the scavenging of heavy metals. Results showed that the organic and sulphide phase was less important in scavenging mechanism –in spite of industrial and petrochemical activities in the study area– than exchangeable and carbonate fraction, which showed to be most important phase with respect to metal scavenging capacity.