Assessment of heavy metal pollution in urban and peri-urban soil of Setif city (High Plains, eastern Algeria)

Heavy metal pollution is a challenging concern that threatens the soil environment and human health worldwide. The purpose of this work is to assess the heavy metals (Cr, Cu, Zn, and Pb) pollution in the urban and peri-urban soils in and around Setif city, eastern Algeria. The work combines chemical analysis of thirty-six soil samples, statistical valuation and interpretation of chemical data and pollution indices (geoaccumulation index, pollution index, and integrated pollution index) with thematic mapping. The average concentrations (in mg/kg) of Cd, Cr, Cu, Pb, and Zn were found < 0.02, 43.35, 43.75, 331.20, and 78.26 mg/kg, respectively. Compared with the French regulatory limits (AFNOR U44-041), Cd, Cr, and Cu still non-hazardous at Setif city scale; however, Zn and Pb concentrations are two to three times higher than the background values referred to the Chinese B-n standard (GB15618-1995). The pollution indices indicate that Pb and Zn represent the highest threats among the studied pollutants and polluted wide areas of anthropogenic activities located respectively in the oldest district of the city, near the industrial zone and near uncontrolled land-fill of domestic and industrial waste. Cu, Pb, and Zn originate seemly from vehicle emission, particles of brakes and tires, and industrial emissions. However, Cr distribution is uncorrelatable with anthropogenic sources. The Cr with an average concentration less than the background value derives seemly from animal feces and organic fertilizers. The integrated pollution index shows that the accumulation of heavy metals in the soils of Setif city from anthropogenic sources reached alarming levels that can disperse into the environment and threaten the human health. The urbanization and industrial development of Setif city are expected to grow and a subsequent heavy metal pollution will be rising prior issue. Corrective measures should be endeavored by the local authorities to mitigate the current environmental situation and a sustainable development plan for the city should be anticipated to guarantee optimal future environmental conditions.

Automated summary

This study assesses the heavy metal pollution in urban and peri-urban soils in and around Setif city, eastern Algeria. The results show that zinc and lead concentrations exceed the Chinese background values, posing a significant threat to human health. Vehicle emissions, industrial emissions, and uncontrolled waste landfill are identified as the main sources of pollution. The study highlights the need for measures to mitigate heavy metal pollution in Setif city and emphasizes the importance of a sustainable development plan to ensure optimal future environmental conditions.