Oral and respiratory bioaccessibility of As, Cd, Cu, Pb and Zn from urban and mining soils (Part I)

Abstract

Heavy metals or potentially toxic elements (PTE) are found in soils in low concentrations, but the input of these elements through anthropic sources can increase the concentrations of heavy metals in soils and cause several negative effects on human health. The oral and the respiratory bioaccessible pools of As, Cd, Cu, Pb and Zn will be investigated in soil samples from urban and mining areas located in the Brazilian cities of Piracicaba and Apiaí, state of Sao Paulo, and Santo Amaro, state of Bahia. We will test procedures based on ingestion and inhalation of urban soils and soils contaminated with mine waste. The Unified BARGE Method (UBM) will be used to determine the bioaccessible content in the gastrointestinal (GI) tract while the Gamble's Solution will be used to determine the bioaccessible content in the lung fluid. X-ray diffraction (XRD) and scanning electron microprobe analysis (SEM) will be used to characterize the soil mineralogy after extractions, in order to evaluate the interaction between the simulated lung fluid/digestive juices and the soils.