GEOCHEMICAL AND GEO-STATISTICAL ASSESSMENT OF HEAVY METALS CONCENTRATION IN SEDIMENT OF SHATT AL-BASRAH, IRAQ

The distribution of metals in sediment of Shatt Al-Basrah canal (Basrah Governorate, South of Iraq) , was assessed to characterize the geochemistry of four heavy metals Cu, Ni, Pb and Zn in sediments for five sites and the assessment of heavy metals was conducted using pollution Load Index (PLI), Sediment Quality Criteria (QSm) and Geo-accumulation Index (I-geo). The metals concentrations showed a homogeneous distribution and similar pattern and it was within the acceptable level during the study time (2014-2015). The average PLI of the canal was evaluated as 0.0056; unpolluted (PLI<1). The toxicity risk in sediment is negligible according to the mean quality in sediment (QSm) with average 0.0078 (QSm<0.1) for the five sites. The I-geo mean values show heavy metals in sediment are ranked as: Zn <Cu<Ni< Pb which remain in grade 0 (unpolluted) in all sites indicating that the sediments are in background value with respect to these metals.