Assessment the concentration, health risk, and source of potentially toxic elements in soils around the Shahid Rajaee thermal power plant,, Qazvin

This research aims to assess the concentration of potentially toxic elements (PTEs) in the soils around the Shahid Rajaei Combined Cycle Power Plant, located 25 km from Qazvin. For this purpose, 25 topsoil samples (0 to 10 cm) were collected, and after sample preparation, the physico-chemical parameters of the samples (including soil’s texture, pH, organic matter, calcium carbonate and cation exchange capacity) were measured. The concentrations of PTEs were determined using an ICP-OES device after strong acid digestion. The obtained results indicate that the average concentration of PTEs decreases in the following order: Mn > Zn > V > Cu > Cr > Pb > Ni > Co > As > Sb > Cd. Enrichment factor values showed that the studied soils are slightly enriched in Cd, Cr and Cu, and are significantly polluted with Pb, Sb, and Zn. Correlation coefficient values, cluster analysis, and principal component analysis show that Cu, Ni, Pb, and Zn are mainly from industrial activities, while As and Cd are probably entered into the soil through agricultural practice (i.e., application of chemical fertilizers and pesticides). Indeed, the highest concentrations of Cu, Ni, Pb, and Zn are recorded in the soil samples collected close to the power plant station in the downwind direction (S-N and NW-SE), indicating that the power plant activity is a possible source of these elements in the studied soils. The health risk assessment of PTEs indicates that As, Cr and Ni cause a cancer risk to children through ingestion. The carcinogenic risks of As, Ni, Cr, Pb, and Cd through all the three exposure routes are higher for children than for adults.