Antimony and arsenic uptake by plants in an abandoned mining area

The degree of antimony ( Sb) and arsenic ( As) pollution and their bioavailability in mining- affected grassland soils were determined. Antimony and As concentrations in aboveground parts of plants, collected in three consecutive years, were measured to investigate their uptake capacity, food chain contamination, and ecological risks. Total Sb and As contents in soils ranged from 60 to 230 mg/ kg and from 42 to 4530 mg/ kg, respectively, indicating a high degree of pollution of soils. The mobile fractions of Sb ( 0.02 - 0.27% of the total Sb content) and As ( 0.02 - 0.70% of the total As content) in soils, which reflect the plant- available portion, are extremely low compared to total Sb and As contents in soils. The Sb and As contents in plants were also very low in both study areas. This lower accumulation of Sb and As in the plants is attributed to the low bioavailability of Sb and As in mine soils. Antimony and As contents in some plants were lower than the controls, and the concentrations in some plants were slightly higher than the normal grass mean level but were less than the phytotoxic or toxic levels for human or livestock consumption. The results of this study demonstrate that the plants growing in these mining areas, which have evolved As and Sb tolerance and detoxification capacity, can be cultivated to phyto-stabilize the metalloid- contaminated mining sites.