Urban geochemistry assessment using pollution indices: a case study of urban soil in Kirkuk, Iraq

This study aims to use the pollution index (PI) and integrated pollution index (IPI) to evaluate the heavy metals in the urban soil in Kirkuk governorate at north part of Iraq. The pollution indices are powerful tools for assessing the eco-toxicity which is very important issue that influences the ecosystems and human health. The heavy metals (Cr, Co, Ni, Cu, Zn, As, Ag, Cd and Pb) were investigated in soil samples collected from various land use categories including residential (RE), commercial (CM), industrial (IN), green space (GS), open space (OS) and roadside (RS). Heavy metals are distributed in the urban soils with content that has a range less than the average geochemical background, but exceeded the background by maximum values. High concentration of Ni, Cr and Co is observed in residential and open space soils. The integrated pollution index revealed that the industrial soil is highly polluted, roadside, commercial, and residential soil categories are of middle pollution level, whereas low pollution level was recorded only in the open and green space soils. Lead, silver, and zinc appear to be linked with industrial sources.