Industry Caused Heavy Metal Pollution in the Soils of North-Iraq

Abstract

In this study, the heavy metal pollution in soils of Northern Iraq caused by industry was determined. A total numbers of 48 surface soil samples of near (0.2 km) and far away (2 and 10 km) from the pollution sources were taken from Dhok, Erbil, Koyia, and Sulemania cities and the concentrations of Fe, Ni, Zn, Cd, Cu, Co, Pb, As, Mo, Cr, Se, Sb, and Hg were determined. When comparing the 0.2 km soil sampling position, all of heavy metal contents generally decreased at 2 and 10 km sampling positions with increasing distance from the pollutant sources. The mean values of Ni, Cd, Hg were found in high level compared to limit values. The maximum values of Fe and Zn contents were also found higher than the limit values. The decreases in Cd, Mo and Cu contents due to increasing distance from the pollutant sources were found significant (P<0.05) statistically. The highest heavy metal content was obtained for Ni in the soil samples taken from Dhouk, Koyia, Erbil and for Zn in the soil sample of Sulemania. The soil samples of Dhok and Sulemania had higher Ni, Cr, Zn and Cu contents than the samples of Erbil and Koyia.