Heavy Metal Pollution in Topsoil and Vegetables in the Typical Mining Area Near Gannan, Jiangxi Province, China

摘要

To provide a theoretical basis for soil management in mining areas, soil and vegetable samples were collected from the vegetable fields at a depth of 0–20 cm near the tungsten mining area in Ganna, China, and seven heavy metals (cadmium [Cd], copper [Cu], chromium [Cr], lead [Pb], zinc [Zn], arsenic [As], and mercury [Hg]) were analyzed by atomic absorption spectrophotometry and atomic fluorescence method. Health risk assessment was used to determine the health risks of the contaminated vegetables and soils. Results showed that the soil was very seriously polluted by Cd, Hg, and As; leafy vegetables were polluted mainly by Cu, Zn, Cr, and As, whereas rhizome plants were polluted by Cd, Pb, and Hg. Furthermore, correlation analysis and the speciation of heavy metals in soil suggest that Cd, Cu, Pb, Zn, and Cr in vegetables may be derived from the soil, whereas Hg and As may be affected by human beings. After the health risk assessment, it was found that there were greater health risks to children than adults from vegetables contaminated by heavy metals. The target hazard quotients for all heavy metals were all >1. The degree of harm from different metals was ranked as follows: As > Cr > Cd > Cu > Hg > Pb > Zn. So, heavy metal pollution in vegetables was serious, and there was high noncarcinogenic risks that endangers human health.