Survey of Heavy Metals Pollution in Surface Soils Around The Industrial Town of Ahvaz 2

The objective of this study was to assess the extent and severity of heavy metal contamination in surface soils in the surrounding of the industrial town of Ahvaz 2. Sixteen topsoil samples were collected at 0-5 cm depth and were analyzed by ICP-OES for Co. Cr, Cu, Ni, Pb and Zn. One sample was also investigated for mineralogy using X-ray. The abundance of heavy metals measured in these topsoil decreases as follows: Cr>Ni>Zn>Pb>Cu>Co. The minerals in the analyzed sample are composed of quartz, calcite, and halite as major minerals with dolomite and alunite as minor minerals. Results indicate that concentration of heavy metal in surface soil is due to fine grain texture of soil, clay content, alkaline pH, CaCO3 content, Na+ and aluminum oxide content. According to geochemical criteria such as enrichment factor (EF), index of geo-accumulation (Igeo) and pollution index (PI), the soils of the study area are considered to be moderately contaminated with respect to Cr, Ni and Pb, and uncontaminated with respect to Co, Cu and Zn. The calculated results of EF, Igeo and PI of heavy metals are as the following: Ni>Pb>Cr>Zn>Cu>Co.