Pollution and Health Risk Assessment of Cadmium and Lead in Cultivated Soils and Crops Surrounding a Lead-Zinc Mine in Yunnan Province

Mining activities have contaminated the surrounding soils and crops. A field investigation was conducted in a lead-zinc mine in Yunnan Province to determine concentrations of Cd and Pb in cultivated soils and crops(potato and maize)and to evaluate their health risk.The average contents of Cd and Pb in soils were 12.93 mg·kg-1and 2 246.48 mg·kg-1, respectively, belonging to heavy pollution. The contents of Cd and Pb in plants were respectively 1.41 mg·kg-1and 11.45 mg·kg-1in potato and 1.18 mg·kg-1and 12.50 mg·kg-1in maize.Significant positive relationship was observed between soil Cd and soil Pb contents, and between soil available Cd and soil total P content and available P contents. At soil pH≤6.5, total Cd and Pb were significantly positively correlated with total P and available P. The present results indicate that soil and crop contamination by heavy metals from mining has threatened the health of local residents.