ePrints

Mobilization of As, Fe, and Mn from Contaminated Sediment in Aerobic and Anaerobic Conditions: Chemical or Microbiological Triggers?

Lookup NU author(s): Dr Lucia Rodriguez Freire

Downloads

Full text for this publication is not currently held within this repository. Alternative links are provided below where available.

Abstract

We integrated aqueous chemistry, spectroscopy, and microbiology techniques to identify chemical and microbial processes affecting the release of arsenic (As), iron (Fe), and manganese (Mn) from contaminated sediments exposed to aerobic and anaerobic conditions. The sediments were collected from Cheyenne River Sioux Tribal lands in South Dakota, which has dealt with mining legacy for several decades. The range of concentrations of total As measured from contaminated sediments was 96 to 259 mg kg^–1, which co-occurs with Fe (21 000–22 005 mg kg^–1) and Mn (682–703 mg kg^–1). The transition from aerobic to anaerobic redox conditions yielded the highest microbial diversity, and the release of the highest concentrations of As, Fe, and Mn in batch experiments reacted with an exogenous electron donor (glucose). The reduction of As was confirmed by XANES analyses when transitioning from aerobic to anaerobic conditions. In contrast, the releases of As, Fe and Mn after a reaction with phosphate was at least 1 order of magnitude lower compared with experiments amended with glucose. Our results indicate that mine waste sediments amended with an exogenous electron donor trigger microbial reductive dissolution caused by anaerobic respiration. These dissolution processes can affect metal mobilization in systems transitioning from aerobic to anaerobic conditions in redox gradients. Our results are relevant for natural systems, for surface and groundwater exchange, or other systems in which metal cycling is influenced by chemical and biological processes.

Publication metadata

Author(s): DeVore CL, Rodriguez-Freire L, Villa N, Soleimanifar M, Gonzalez-Estrella J, Ali AMS, Lezama-Pacheco J, Ducheneaux C, Cerrato JM

Publication type: Article

Publication status: Published

Journal: ACS Earth and Space Chemistry

Year: 2022

Volume: 6

Issue: 7

Pages: 1644-1654

Print publication date: 21/07/2022

Online publication date: 28/06/2022

Acceptance date: 28/06/2022

ISSN (electronic): 2472-3452

Publisher: American Chemical Society

URL: https://doi.org/10.1021/acsearthspacechem.1c00370

DOI: 10.1021/acsearthspacechem.1c00370

Altmetrics

Share