Investigation of heavy metals contamination in east Urmia agricultural soil based on contamination indicates

Pollution and geoaccumulation of heavy metals in soil and agricultural products owing to human activities and natural factors pose significant environmental issues that pose severe risks to human health and food security. To address these concerns, the concentrations of heavy metals, including As, Sb, Cu, Mo, Pb, and Zn, were randomly collected from 20 soil samples taken from depths of 0–30 cm in the eastern agricultural area of eastern Urmia. After sample preparation, the total concentrations of these elements in the soil samples were extracted using hydrochloric and nitric acids and then measured using ICP-OES. The results indicated that the mean concentrations of total As, Sb, Cu, Mo, Pb, and Zn in the study area were 7.04, 1.02, 21.57, 0.357, 7.60, and 57.19 mg/kg, respectively. These concentrations were lower than the limits set by the Iranian Environmental Protection Agency. The mean pollution factor and enrichment coefficient in the region were the highest for As, followed by Sb, Zn, Pb, Cu, and Mo. The average infection index was 13.46, which indicated a moderate degree of soil contamination. The Earth Repletion Index for Cu and Mo was between 0 and 1, suggesting a natural origin, whereas for As, Cu, Pb, and Mo it was greater than 5, indicating high pollution levels. Based on the Pearson coefficient, there was a high correlation between Pb, Sb, Cu, and Zn, suggesting a common origin or similar geochemical behavior.