Source and nature of inhaled atmospheric dust from trace element analyses of human bronchial fluids

Rapid volcanic eruptions quickly ejecting large amount of dust provoke accumulation of heavy metal in people living in the rounding areas. Analyses of bronchoalveolar lavages (BAL) collected on people exposed to the paroxysmal 2001 Etna eruption reveal a strong enrichment on many heavy toxic metals. Comparing the BAL to the dust composition of the South-eastern Sicily, we found that only the V, Cr, Mn, Fe, Co and U enrichment can be related to the volcanic event, whereas Ni, Cu, Cd and Pb contents come from the dissolution of particles having an anthropogenic origin. Furthermore, the nature of these inhaled anthropogenic particles is revealed by anomalous La and Ce concentrations in studied BAL that are consistent to a mixture of road dust and emissions of petroleum refineries. Obtained results indicate that trace element distribution in BAL is suitable to represent a tracer or human exposure to different inhaled atmospheric particulates, allowing to investigate the origin of source materials inhaled by people subjected to atmospheric fallout.