Heavy metal contamination in mangrove sediments in Klang estuary, Malaysia: Implication of risk assessment

Deterioration of environmental quality in estuaries leads to a high risk of destruction of marine life. Heavy metal (Mn, As, Cu, Zn, and Pb) concentration in mangrove sediment in the Klang estuary was evaluated to identify any potential risk of contamination resulting from the rapid development along the Klang river. Several indicators were used to evaluate the pollution status: geo-accumulation (Igeo), contamination factor (CF), degree of contamination (DC), potential ecological risk index (PERT) and risk assessment code (RAC). The results indicate that As and Pb concentrations exceeded the threshold effect level, while Mn, Zn, and Cu posed no adverse biological impacts. In addition, I-geo, CF, and PERI values showed minimal risk of heavy metal pollution in the study area. However, RAC for Zn exhibited high environmental risk. On the other hand, Cu and Mn showed medium environmental risk, while Pb and As showed no environmental risk. These results can increase awareness of the mitigating action that mangrove forests naturally provide against pollution, and provide information to design future plans and policies towards more sustainable development in the area.