Ecological risk assessment of heavy metals in the Sidi Boughaba Lake, Morocco

Abstract

The goal of the research was to evaluate the heavy metal detection and potential ecological risks in lake’s water. Geological formations consisting essentially of sandstone and quaternary marine or dune sands characterize the study area. With a climate of the Mediterranean type winters are mild and humid, whereas summers hot and dry. At the analysis center of the Faculty of Sciences, the monitoring of ETMs is carried out by ICP-MS, the processing of data and the validation of the analysis method have been drafted according to the NF T 90-120 standard applicable to the analysis in a laboratory. The analysis covers concentrations of heavy metals, which include Cu, Zn, Mn, Fe, Pb and As, in the water. Pollution load index ( PLI) values were above one (>1) which indicates progressive deterioration of the water quality. However, contamination factor ( CF) values of Pb and Cu, ranging from 8.31 to 15.68 and from 5.5 to 28.05 respectively, show that the studied water remains under a strong impact by Pb and Cu. Considering the severity of the ecological risk ( Er) for a single metal, the descending order of contaminants is Cu > Pb > Mn > Fe > Zn. In relation to the total ecological risk index ( RI), water from the lake shows low to considerable ecological risk.