Risk associated with occurrence of toxic elements in the environment surrounding landfills in An Giang Province, Vietnam

The study aimed to evaluate the concentration of potentially toxic elements in the soil samples of landfill sites in An Giang province. Eighty-eight soil samples were collected from five landfills. The potentially toxic elements including Cu, Zn, Pb, Cd, and As were analysed and compared with the National technical regulations on the allowable limits of heavy metals in the soils. A cluster analysis was applied to identify the sampling sites with similar soil toxic elements properties. The ecological potential risk index was used to determine the risk of the landfills to the ecosystem. The results showed that four out of five potentially toxic elements were detected in the soil, and their concentration decreased in the order of Zn > Cu > Pb > As. Most of the potentially toxic element concentrations were within the allowable limits, except for Cu and As in some positions. The ecological potential risk index in unsanitary landfills was higher than that in a sanitary landfill; however, the level of risk was low. The occurrence of toxic elements in the soil around the landfills affects the ecosystems as well as human health. Therefore, it is necessary to prevent the effect of heavy metals in the surrounding environments.