Assessment of Pollution by Heavy Metals in Surface Sediments at Wadi Al-Wala, Jordan

Abstract

The concentration levels of Cd, Fe, Cu, Mn, Pb, and Zn in sediment samples from Wadi Al-Wala were determined in order to assess the level of contamination. Sixteen sediment samples were collected during the period from 2016.The highest concentrations of Zn, Cu and Cd originate mainly from anthropogenic sources such as discharge of agricultural materials residuals and the weathering of surrounding rock formations. Sediment contamination assessment was carried out using the pollution indicators such as enrichment factor (EF), pollution load index (PLI), and geo-accumulation index (Igeo). The results of Igeo analyses of Wadi Al-Wala sediments proved that concentrations of Mn, Cu, Pb, and Fe are safe and these elements are practically unchanged by anthropogenic influences, while the concentration of Zn and Cd exceeded the average value. PLI analysis proved that Wadi Al-Wala is moving towards a probable environmental pollution with regard to heavy metals (Zn and Cd). The results of EF showed high concentrations of Zn, Cu and Cd in the study area. Correlation coefficients analysis showed varying relation between the different parameters depending on the input sources of each metal. In order to protect the sediments from further contamination, monitoring and management of the heavy metal anthropogenic discharges is suggested.