Soil pollution identification and human health risk assessment of soil heavy metals in an abandoned mine area in the Republic of Korea

In this study, the Geo-accumulation index (I_geo), Human Health Risk Assessment (HRA), and Ecological Risk Index (ERI) were utilized to examine the risks associated with the soils at the DaeyangYeongseong mine. Brassica juncea and Raphanus sativus were employed in the ecological toxicity test. In all soil samples, the mean I_geo value of arsenic measured 3.15, and cadmium measured 6.63, indicating a very high level of heavy metal contamination. The carcinogenic risk of cadmium and arsenic for adults was 4.30×10-3 and 1.43×10-5, respectively. For children, these values were 3.92 × 10-2 and 1.33 ×10-4, exceeding the acceptable level (1×10-6). In all soils, cadmium showed extremely high ecological risk levels, and arsenic had extremely high risk levels in 34.8% of the total area. This was also confirmed in toxicity assessments using plants. Therefore, arsenic and cadmium were found to be the main causes of soil contamination and ecological risk.