The aim of this study was to monitor the pollution of potentially toxic elements in the soils surrounding the Mohammadabad landfill, determine their sources, and assess health risks. 19 soil samples were collected from 11 sampling stations (including sub-soil in some stations) around the landfill, and 1 sediment sample from the leachate settling ponds. The concentration of elements were measured using ICP-MS, and the data were analyzed using statistical methods and geochemical indices. The highest contamination levels were associated with As, Cu, Ni, Co, Mn, and Zn, and the most polluted station was located adjacent to the urban waste landfill. The sediment from the industrial pond also exhibited severe potentially toxic elements contamination. The pollution load index in majority of sampling sations fall within the significant risk category, while the ecological risk in some samples (located adjacent to the municipal waste depot and south of the sampling area) was classified as very high. The health risk assessment showed that, for all elements, the ingestion pathway (HI > 1) posed a health risk to both children and adults in samples collected near the landfill site. The carcinogenic risk for As and Cr through ingestion was considerable, while lead posed a serious risk through all exposure pathways. In contrast, Ni via ingestion remained within acceptable limits. Statistical analyses including principal component and cluster analysis showed that As, Cu, Pb, Cd, and Zn were more influenced by anthropogenic sources, likely due to the direct impact of the landfill. Also, based on the T-test, it was determined that there was no significant difference in average concentration of elements between topsoil and subsoil samples. Ultimately, the findings emphasized the importance of managing and safely disposing of sludge from the industrial leachate pond due to the high concentrations of some elements including As, Cu and Zn.
Type of Study:
Original Research |
Subject:
Environmental Geology Received: 2024/11/28 | Accepted: 2024/12/20 | Published: 2024/12/28