GEOACCUMULATION AND RISK ASSESSMENT OF HEAVY METALS IN URBAN RIVER SEDIMENTS

Abstract

The increasing contamination of river sediments with heavy metals poses significant risks to aquatic ecosystems and public health, particularly in urban settings of developing countries. This study evaluates the geoaccumulation and ecological risk associated with selected heavy metals (As, Cd, Cr, Cu, Pb, Ni, Zn) in sediments from urban rivers across major Pakistani cities. Sediment samples were analyzed using ICP-MS, and contamination was assessed through geoaccumulation index (I_geo), enrichment factor (EF), and potential ecological risk index (PERI). Results indicate high levels of Cd and Pb contamination in industrial zones, with I_geo values suggesting moderate to strong pollution. The findings underscore the urgent need for sediment monitoring and integrated watershed management in Pakistan’s urban rivers.