Assessment of heavy metal contaminated agricultural soils affected by mining in Ganzhou China

Abstract

Soil heavy metal contamination caused by mining is a significant issue in China. The site of this study is located in Ganzhou of Jiangxi province in China. 102 soil samples were collected along the Yangmeijiang River. ICP-MS was used to obtain heavy metal concentrations in the soils. Significant contamination was found in the agriculture soils adjacent to the river and near mining industries. The heavy metal concentrations were high at depths of 20 cm and 40 cm. According to geo-accumulation index I geo , the soils were extremely polluted with Cd ( I geo = 4–7), heavily polluted with As ( I geo = 2–4), moderately to heavily polluted with Pb, Zn and Cu ( I geo = 0–4) and virtually unpolluted with Ni, Cr and Hg ( I geo = -3–1). These results may be a result of large amounts of As, Cd, Pb, Cu and Zn being produced by nearby copper heap leach facilities. Based on USEPA method for health risk assessment, with ingestion being the major pathway for health risks, heavy metals pose a non-carcinogenic risk to adults ( HQ max = 2.87, CR max = 4.25 × 10 - 4 ), but pose both non-carcinogenic and carcinogenic risk to children ( HQ max = 20, CR max = 1.15×10 -3 ). Overall, As, Pb and Cr pose the primary health risks for the soils in the study area.