An Assessment of Heavy Metal Soil Contamination in a Steel Factory and the Surrounding Area in Erbil City

The objective of the current study is to assess the soil contamination caused by a steel factory to the surrounding areas in Erbil city. The highest value of all metals (with the exception of Al) was observed in the Erbil Steel Company (E.S.C.). The mean concentration of heavy metals followed this pattern: Fe Al Zn Mn Ti Pb Cu Ni Cr V Co As ≥ Mo Cd. Only the concentration of Ni (70-181 ppm) exceeded the WHO limits in all the studied sites. Soil pollution was assessed using many indices including: index of geoaccumulation (Igeo), enrichment factor (EF), contamination factor (CF), degree of contamination (Cdeg), pollution load index (PLI), element contamination index (ECI) and the overall metal contamination index (MCI) using Al as a reference element. In comparison with the local soil backgrounds from Erbil city, moderate contamination was observed generally in the Sahdawa, Shamamal and Sardasht areas with As, Co, Cr, Mn, Mo, Ni, Ti, V and Zn. However, Sahdawa was found considerably contaminated by Pb (CF = 4.79). Sites (2-8) have a considerable degree of contamination (16≤ Cdeg 32). PLI in all the studied sites (except for Sardasht) indicated a deterioration in the site quality (PLI 1). The R-mode factor analysis extracted three factors: first, the metals coming mainly from the E.S.C. activities accounting for 72.292 % of the total variance. Second, the lithogenic factor accounting for 14.638 % of the total variance, and finally the sampling date accounting for 6.667% of the total variance.