It is essential to use specific background concentrations that reliably represent the characteristics of the area under evaluation. In this study, we analyzed the concentrations of heavy metals using the results of the 2022 surveys of the actual state of soil contamination from 17 metropolitan governments. The overall national averages of natural background concentrations were obtained from the results of the 2021-2022 soil monitoring network and compared with that obtained in previous studies. In addition, the natural, anthropogenic, and natural/anthropogenic background concentrations were separately obtained for each of the 17 metropolitan governments. The contamination factor (CF), one of the most commonly used soil pollution indices, was selected and applied to evaluate the soil contamination levels for the 2022 survey results. Variations ranging from 0.3 to 1.4 times were obtained between the national average natural background concentrations from the 2021-2022 network and those from that commonly used in previous studies in Korea. Moreover, the natural and natural/anthropogenic background concentrations of each metropolitan government varied significantly. Compared to the cases using the national average background concentrations, the soil pollution level of the metropolitan governments could be overestimated or underestimated when using the regional average background concentrations.

Keywords: Surveys of the actual state of soil contamination, Soil monitoring network, Heavy metals, Soil pollution indices, Contamination factor