Dust produced by mining activities is a world-wide health concern. An estimated 163,000 tonnes of particulate matter (PM) are released annually in Canada by mining activities. Alteration of dust particles in soils often controls the subsurface fate of metal(loid)s associated with the emitted particulate matter. For example, bulk analytical methods show that Cu-Fe-sulfide PM have been deposited onto organic-rich soil layers (A<sub>h</sub>-horizon) adjacent to the Timmins Kidd Creek metallurgical site, Ontario, Canada. Focused Ion Beam sections were extracted from the interior of organic material (OM) as well as along the interface of OM to the attached Cu-Fe sulfide particles. Subsequent Transmission Electron Microscopy showed that copper can occur as metallic copper nanoparticles near the interface, in magnetite precipitates within the OM, and within the interior of OM. These observations suggest that Cu is sequestered within organic rich soil layers through various redox and precipitation mechanisms. While studies have shown the sequestration of Cu as metallic Cu nanoparticles in roots, this study shows for the first time that Cu is sequestered as Cu nanoparticles in surficial organic-rich soils layers.

Nanoscale examinations on the speciation of copper within organic matter from soils contaminated by mining activities

255th National Meeting (2018)

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