Determination, speciation and evaluation of bioavailability (transfers between water-soil-plant systems) of technologically critical elements (TCE)

Abstract

Technologically critical elements (TCE) are a set of ultra-trace elements with the particularity of being scarce on the Earth's surface, but its use is increasing in modern technological applications due to their specific properties. These elements include the metals of the Platinum group, Rare Earths and others, like, Nb, Ta, Ge and Te. Due to its high demand in the fields of communication, transport and energy, TCE extractive production has recently grown by several orders of magnitude. This led to a growing interest in understanding its environmental and ecotoxicological behaviours and, consequently, to a demand for the development of appropriate analytical techniques for determining TCE. However, methods for determining, speciation and the bioavailability of these elements are scarce in literature until today. This impedes a consistent understanding of the biogeochemistry of these elements. In view of the situation exposed above, it is intended to establish and develop new methods for the determination, speciation and evaluation of the bioavailability of TCE in surface waters, plants and soils. For this, new methods will be developed based on techniques with inductively coupled plasma mass spectrometry and diffusive gradients in thin films (with conventional and newly developed binding agents). The studies will be directed to three sites subjected to supposed TCE contamination: 1) The Corumbataí River basin (State of São Paulo) which is highly affected by the Santa Gertrudes ceramic industrial complex (the largest ceramic industrial pole in Latin America); 2) The Paraíba do Sul River in the Region close to São José dos Campos (SP), where there are companies of electronic devices that release treated effluents to these waters; 3) The Uranium mining complex INB (State of Minas Gerais, in the municipality of Caldas) with enriched soils in Ce, Nd, La, Th and Zr. The focus of the proposal is directed towards an innovative approach that can start a new line of research at CEA/UNESP and, possibly, in the State of São Paulo. In addition, despite being directed to areas in Brazil, the proposal has an international character, as it will include other researchers allocated outside of Brazil, mainly researchers from the Montanuniversität Leoben (Austria), experts in TCE. (AU)