Pollution Load Index for Heavy Metals of Agricultural Soils Adjacent to Industrial Complexes in the Jeon-Buk Regions of Korea
Sorakon Suwanmanon, Ki In Kim
Abstract
Monitoring heavy metal concentrations in agricultural soils close to industrial complexes plays a critical role in ascertaining the safe agricultural environment in Korea and its product qualities. Objective of this study was to assess the heavy metal concentrations in agricultural soils close to industrial complexes. Fifteen industrial complexes in 7 counties in Jeon-Buk Province (Gochang, Iksan, Jeongeup, Gimje, Imsil, Jangsu, and Wanju) were selected for monitoring soil heavy metal concentrations in 2019. The soil samples were analyzed for 7 heavy metals, including arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), nickel (Ni), lead (Pb), and zinc (Zn) within 500 meter and 1,000 meter radius at each industrial complex boundaries. Heavy metal concentrations in soils ranged from 0.3 to 8.0 mg kg -1 for As, from 0.2 to 1.5 mg kg -1 for Cd, from 1.7 to 62.9 mg kg -1 for Cr, from 1.4 to 22.5 mg kg -1 for Ni, from 4.1 to 26.0 mg kg -1 for Pb, from 0.0 to 1.4 mg kg -1 for Hg, and from 25.9 to 283.5 mg kg -1 for Zn. Heavy metal concentrations in soils were lower than the levels of Soil Contamination Warning Standard (SCWS). The pollution index (PI) values of all seven heavy metals (As, Cd, Cr, Cu, Ni, Pb, and Zn) ranged from 0.1 to 0.4 for top and sub soils indicating that these soils are not polluted. The pollution load index (PLI) values using 7 heavy metals at each county ranged from 0.10 to 0.24 for top and sub soils and the number was categorized into Group 2 which is unpolluted. These results suggested that monitored agricultural soils near industrial complexes in Jeon-Buk province in 2019 were unpolluted by heavy metals and safe for agricultural activities.