Recently, uranium-containing respirable dust has been assessed for cardiovascular and numerous metabolic diseases in Navajo nation residents near Grants Mining District (GMD) in Western New Mexico. Many of these studies are focused on understanding the fate and impact of these dust particles in various lung environments. However, the chemistry behind the uranium leaching from inhaled-dust particles with larger particle sizes (typically ~10mm) that are cleared to the human gastrointestinal tract (GIT) has not been studied extensively. In this study, uranium solubility of dust collected from five sites near the Jackpile and St. Anthony mines in GMD has evaluated using two simulated gastrointestinal fluids in fasted state conditions: Simulated Gastric Fluid (SGF) and Simulated Intestinal Fluid (SIF). The dissolution of uranium from dust, at least in part, depends on the mineralogy of the dust itself. Further, geochemical calculations performed with PHREEQC 3.3.8 suggest that the dust samples rich with andersonite (Na2Ca(UO2)(CO3)3.6H2O), have higher uranium dissolution in SIF compared to that of SGF, and the presence of kaolinite greatly impact on the uranium leaching in each fluid. These geochemical calculations are in good agreement with the experimentally observed results. Finally, this study gives insight into the mineralogy controlled toxicological assessment of uranium-containing inhaled-dust that has cleared to gastrointestinal tract.

Mineralogy controlled dissolution and toxicological assessment of uranium dust in simulated gastrointestinal fluids

ACS Fall 2021

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.