There is a world concern in relation to hazards of heavy metals in the environment. Soil pollution by heavy metals can directly or indirectly affect the health of organisms. Increasing heavy metals concentration in soil likely cause the increase of their entrance to plants. As a result, their accumulation especially in crops will be dangerous for human health. The aim of this study is to determine the spatial distribution of cadmium (Cd), zinc (Zn), and vanadium (V) in soils of Hamadan province, pollution assessment of soil, potato, wheat, barley, alfalfa, and corn, and the investigation of the health risk in the crops. Surface soil samples (0-20 cm) were collected by random systematic method. The concentration of heavy metals and some soil properties including pH, EC, and percentage of organic matter, sand, silt, and clay were determined. Satellite images were used to find out soil sampling points located on the agricultural lands and samples of potato, wheat, barley, alfalfa and corn were collected. The Kriging method precision of different models was compared using Mean Absolute Error (MAE) and Mean Bias Error (MBE). The method with higher precision was selected to mapping of heavy metals in the soil. The background concentration of both Cd and V, as well as Zn were calculated by median and Index of Geochemical Distribution (IGD), respectively. Soil pollution status was also determined using Index of Geochemical Load (IGL). Heavy metals Transfer Factor (TF) from soil to plants were calculated to identify their accumulations in the crops. The health risk potential of heavy metals in the wheat and potato were assessed with Health Risk Index (HRI). The results showed that the concentrations of studied elements in the soil were in the natural range; and were lower than the maximum acceptable concentration for plant toxicity. Cd, Zn, and V concentrations in the plants were lower than their toxicity. The Exponential model of disjunctive Kriging and Gaussian model of simple Kriging were shown higher precisions for both Cd and V, and Zn, respectively. Overlay of soil heavy metals spatial distribution, geology and land use maps were shown that Cd concentration depends to geology and agriculture. In addition to parent material, agriculture play an important role in Zn enrichment of soil. The geology was major factor to control the concentration of V in soil. According to IGL, only 10 soil samples located on the agricultural lands, were considered as polluted. The highest TF was observed for Cd in potato demonstrating that the high accumulation. Based on the HRI, the consumption of wheat and potato containing Cd and Zn didn’t have risk for human health, but the consumption of wheat could have significant risk due to existence of V. Keywords : Hamadan Province, heavy metals, soil pollution, kriging, crops, health risk.
