Evaluation of heavy metal contamination in landfills from e-waste disposal and its potential as a pollution source for surface water bodies

This study examines heavy metal contamination resulting from e-waste disposal in the Illovo DSW landfill, Durban, South Africa, and its potential impact on the Lovu River. A total of 23 samples, collected in triplicate, included 6 water samples, 10 soil samples, 6 sediment samples, and 1 leachate sample collected in October 2023 and February 2024. Eight heavy metals commonly associated with e-waste-arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), nickel (Ni), lead (Pb), selenium (Se), and zinc (Zn)-were analyzed using Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES). The results revealed significantly higher heavy metal concentrations in soils compared to water, with Cd, Cr, Pb, and Zn levels often exceeding those in the leachate. This highlights the role of soil as a reservoir for heavy metals, while water primarily acts as a transport medium where dilution occurs. The most notable contaminants were Cd, Cr, and Pb, with Cd levels at the west landfill boundary (0.1202 mg/L) surpassing concentrations reported in other global studies. The findings underscore the environmental risks posed by landfill leachate, including bioaccumulation in sediments and potential pollution of surface waters. This study emphasizes the urgent need for improved e-waste management practices and stricter landfill regulations to mitigate heavy metal leaching. By exploring the dynamics of heavy metal contamination in a subtropical environment, the research provides valuable insights for enhancing landfill and waste management systems worldwide.