Estimating Heavy Metal Concentrations in Landfill Leachate and the Impact of Waste Segregation in Malaysia

Estimation of heavy metal concentrations in leachate was crucial for effective landfill management and pollution mitigation. The study aimed to estimate the volume of landfill leachate, the heavy metal content in the leachate, and their reduction through waste segregation practices. It was conducted in Malaysia and utilised municipal solid waste volume data from six states and two federal territories. A mathematical empirical model was applied to estimate the concentrations of heavy metals in the leachate. Based on the volume of landfilled waste, an estimated 565,000 cubic metres (m³) of leachate were discharged annually. Among the heavy metals analysed, Pb and Zn exhibited the highest concentrations (8.49 kg/yr). Waste segregation practices reduced heavy metal discharge in leachate, preventing approximately 7.09 × 10⁻⁴ to 5.32 × 10⁻³ kg/yr. Through mathematical modelling, this research provided a cost-effective approach for estimating heavy metal concentrations and supported strategies for addressing environmental and health impacts.