Open AccessBioaccessibility of potentially toxic elements in mine residue particles
Author(s) -
Corona-Sánchez Jesús Eulises,
Ma. del Carmen A. González-Chávez,
Rogelio Carrillo-González,
José Luis García Cúe,
Demetrio S. Fernández-Reynoso,
Matt Noerpel,
Kirk G. Scheckel
Publication year - 2021
Publication title -
environmental science. processes and impacts
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.128
H-Index - 98
eISSN - 2050-7895
pISSN - 2050-7887
DOI - 10.1039/d0em00447b
Subject(s) - environmental chemistry , particulates , chemistry , aqua regia , bioavailability , xanes , nuclear chemistry , metal , spectroscopy , bioinformatics , physics , organic chemistry , quantum mechanics , biology
Mining companies used to abandon tailing heaps in countryside regions of Mexico and other countries. Mine residues (MRs) contain a high concentration of potentially toxic elements (PTE). The wind can disperse dust particles (<100 μm) and once suspended in the atmosphere, can be ingested or inhaled; this is a common situation in arid climates. Nowadays, there is little information on the risk of exposure to PTEs from particulate matter dispersed by wind. The pseudo-total PTE in bulk and fractionated MR after aqua regia digestion, the inhalable bioaccessibility with Gamble solution (pH = 7.4), and the gastric bioaccessibility with 0.4 M glycine solution at pH 1.5 were determined. As and Pb chemical species were identified by X-ray absorption near-edge structure (XANES) spectroscopy. The highest rate of dispersion was observed with 74-100 μm particles (104 mg m-2 s-1); in contrast, particles <44 μm had the lowest rate (26 mg m-2 s-1). The highest pseudo-total As (35 961 mg kg-1), Pb (3326 mg kg-1), Cd (44 mg kg-1) and Zn (up to 4678 mg kg-1) concentration was in the <20 μm particles and As in the 50-74 μm (40 236 mg kg-1) particles. The highest concentration of inhaled bioaccessible As (343 mg kg-1) was observed in the <20 μm fraction and the gastric bioaccessible As was 744 mg kg-1, Pb was 1396 mg kg-1, Cd was 19.2 mg kg-1, and Zn was 2048 mg kg-1. The predominant chemical As species was arsenopyrite (92%), while 54% of Pb was in the adsorbed form. Erodible particle matter is a potential risk for humans in case of inhalation or ingestion.