Accumulation and transport of antimony and arsenic in terrestrial and aquatic plants in an antimony ore concentration area (south-west China)

Abstract

Environmental contextPhytoremediation requires an understanding of bioconcentration and translocation processes that determine behaviour and fate of potentially toxic elements. We studied the distribution of antimony and arsenic in terrestrial and aquatic soil-plant systems in an antimony ore zone. We found that the common climbing plant Kudzu (Pueraria lobata) is suitable for phyto-stabilisation of antimony-bearing tailings, while tiger grass (Thysanolaena maxima) was able to extract antimony and arsenic from contaminated soils. AbstractAntimony (Sb) pollution is a major environmental issue in China. Many historical abandoned tailings have released high concentrations of Sb and its associated element arsenic (As) to surrounding environments. This has prompted the need to understand accumulation and translocation processes that determine the behaviour and fate of Sb and As in contaminated soil–plant systems and to identify suitable plant species for phytoremediation. Here we investigate distribution of Sb and As in terrestrial and aquatic dominant plant species and associated soils, all of which are naturally found in an Sb ore concentration area in south-west China. Total Sb and As concentrations were measured by inductively coupled plasma mass spectrometry (ICP-MS). The percentage of soluble Sb and As in the total concentrations were determined; the results showed that the basic soil environment facilitates the release of Sb and As from contaminated soils, and that Sb has higher mobility than As. Bioconcentration factor (BCF) and translocation factor (TF) were used for evaluating the ability of plants to accumulate and transport Sb and As, respectively. The results indicated that all selected plant species have the potential to tolerate high concentrations of Sb and As. Consequently, this study suggested that Pueraria lobata (PL) can be used as the preferred species for phytostabilisation of abandoned Sb-bearing tailings, given that PL has well-developed roots and lush leaf tissues and the ability to translocate Sb from roots to aboveground parts. Thysanolaena maxima (TM) is suitable for phyto-extraction of Sb and As in contaminated soils.