Fractionation and Bioavailabilities of Antimony and Arsenic Levels in Three Polluted Soils Extracted with sequential extraction methods

Abstract The antimony mining activities caused the surrounding soils easily polluted by heavy metals such as antimony (Sb) and arsenic (As), which accumulated by plant and posed risk. In order to study the fractionation distributions and bioavailabilities of Sb and As in the three contaminated soils (paddy soil, upland soil, waste ore soil) collected from Xikuangshan (XKS) antimony mine, the world’s largest antimony ore mine, there four different sequential extraction methods (named BCR improvement, Tessier, Leleyter, and Eight-step, respectively) were carried to analysis fractionations of Sb and As The results showed that the concentrations of Sb (145.00-6876.00 mg·kg−1), and As (18.20-380.00 mg·kg-1) were found in three soils demonstrating those soils were con-taminated by Sb and As compound pollution, In particularly, the concentrations of Sb and As were in the order: waste ore soil (WOS) > upland soil (US) > paddy soil (PS). Among four sequential extraction procedures, the mean extraction efficiencies of Sb and As were 87.23% and 81.75% with BCR improvement method, 68.66% and 66.80% with Tessier’s method, 71.90% and 88.15% with Leleyter’s method, 94.62% and 96.17% with Eight-step method, indicating that the highest and lowest extraction efficiencies of Sb and As were Eight-step and Tessier’s method, respectively. Except for the Eight-step method, the prominent fractionations of Sb and As were the residu-al fractionation in PS, US and WOS extracted by the other three methods. The per-centage of bioavailability fractionations of Sb and As in PS, US and WOS were (Sb 1.82, 3.73, and 9.25%; As 1.52, 0.02, and 5.29%) in BCR improvement method, (Sb 0.99, 1.79, and 3.20%; As 0.20, 0.11, and 2.48%) in Tessier’s method, (Sb 1.10, 1.16, and 1.45 %; As 0.94, 0.60 and 2.73%) in Leleyter’s method, (Sb 1.62, 1.56, and 1.67%; As 2.24, 3.70, and 5.75%) in Eight-step method. Therefore, the extraction ef-ficiencies of Sb and As was Eight-step method, while the BCR improvement method was the optimal method for bioavailabilities of Sb and As.