Evaluation of heavy metal contamination of sediments of the estuary of the Bouregreg (Atlantic Coast,Morocco) [Evaluation de la contamination en métaux lourds des sédiments de l'estuaire de Bou Regreg (Côte atlantique,Maroc)]

The aim of this study is to evaluate the degree of metal pollution of bouregreg estuarine sediment. the sediments were sampled in eight stations along the estuary for analysis of a set of physical parameters (ph,electrical conductivity (ec) and magnetic susceptibility (ms) and heavy metals and metalloid (cd,cr,cu,pb,zn and fe). the contamination factor (cf) and the index of the pollution load (pli) were used for the evaluation of metal contamination of sediments. the results of this study suggest that bouregreg estuarine sediments are relatively more contaminated with heavy metals. the contents of the metals analyzed are high and variable in sediments along the estuary. cf values indicate a moderate to considerable contamination for most stations. pli values indicate that all stations,except the stations s2,s6 and s8,are polluted. the correlation matrix between all metal elements indicates that they are derived from similar sources. pollution sources are anthropogenic related to the bouregreg valley development project and to urban and industrial discharges. pollution of the estuary remains important despite the measures taken by local authorities since 2006,such as the closure of the landfill oulja side of the city of salé and pretreatment of wastewater side of the city rabat.