ABSTRACT
Vanadium (V) has been documented as an essential and toxic element for humans, depending on its speciation and concentration. Due to its wide applications in modern technologies, increasing demand for V has inevitably caused its discharges into soil and environmental systems, raising concerns of food safety, human health and environmental sustainability. To address this environmentally important issue, knowledge of V speciation in aqueous and solid phases of soils is an essential prerequisite for determining (bio)availability, solubility, toxicity and mobility in soil-biota systems. This chapter describes (i) V speciation in aqueous solution, and (ii) V speciation in solid phases of minerals, soils and sediment, with an emphasis on an advanced understanding of V speciation using X-ray absorption near-edge structure (XANES) spectroscopy. Key challenges in X-ray absorption spectroscopy (XAS) for V speciation in soils and sediments are also discussed.
