Potential ecological risk of hazardous elements in different land-use urban soils of Bangladesh

Abstract

Soil pollution, influenced by both the natural and anthropogenic factors, significantly reduces environmental quality. In this study, six hazardous elements (Cr, Ni, Cu, As, Cd and Pb) in 12 different land-use urban soils from Bangladesh were assessed. The ranges of Cr, Ni, Cu, As, Cd and Pb in studied soils were 2.4–1258, 8.3–1044, 9.7–823, 8.7–277, 1.8–80 and 13–842mg/kg, respectively. More than 70% of soil samples exceeded the Dutch target value for Ni, Cu, As, Cd and Pb concentration in soil, indicating a potential risk to the environment. Certain indices, including the enrichment factor (EF), pollution load index (PLI) and contamination factor (Cfi), were used to assess the ecological risk posed by hazardous elements in soils. The mean range of PLI was 1.5–10, indicating progressive deterioration of soil due to metal contamination. However, the Cfi values of Cd ranged from 3.7 to 35 revealed that the examined soils were strongly impacted by Cd. Considering the severity of potential ecological risk for single metal (Eri), the descending order of contaminants was Cd>As>Cu>Pb>Ni>Cr. In view of the potential ecological risk (PER), soils from all land uses showed considerable to very high potential ecological risk.