Publication Details

Reference Category Journals
DOI / URL link
Title (Primary) Environmental risk of arsenic mobilization from disposed sand filter materials
Author Le, A.V.; Muehe, E.M.; Drabesch, S.; Pacheco, J.L.; Bayer, T.; Joshi, P.; Kappler, A.; Mansor, M.
Journal Environmental Science & Technology
Year 2022
Department UMB
Volume 56
Issue 23
Page From 16822
Page To 16830
Language englisch
Topic T7 Bioeconomy
Supplements https://pubs.acs.org/doi/suppl/10.1021/acs.est.2c04915/suppl_file/es2c04915_si_001.pdf
Keywords arsenic-bearing water treatment residuals; open disposal; disposed filter-sand; microbial reduction; colloidal transport; arsenic remobilization
Abstract Arsenic (As)-bearing water treatment residuals (WTRs) from household sand filters are usually disposed on top of floodplain soils and may act as a secondary As contamination source. We hypothesized that open disposal of these filter-sands to soils will facilitate As release under reducing conditions. To quantify the mobilization risk of As, we incubated the filter-sand, the soil, and a mixture of the filter-sand and soil in anoxic artificial rainwater and followed the dynamics of reactive Fe and As in aqueous, solid, and colloidal phases. Microbially mediated Fe(III)/As(V) reduction led to the mobilization of 0.1–4% of the total As into solution with the highest As released from the mixture microcosms equaling 210 μg/L. Due to the filter-sand and soil interaction, Mössbauer and X-ray absorption spectroscopies indicated that up to 10% Fe(III) and 32% As(V) were reduced in the mixture microcosm. Additionally, the mass concentrations of colloidal Fe and As analyzed by single-particle ICP-MS decreased by 77–100% compared to the onset of reducing conditions with the highest decrease observed in the mixture setups (>95%). Overall, our study suggests that (i) soil provides bioavailable components (e.g., organic matter) that promote As mobilization via microbial reduction of As-bearing Fe(III) (oxyhydr)oxides and (ii) As mobilization as colloids is important especially right after the onset of reducing conditions but its importance decreases over time.
Persistent UFZ Identifier https://www.ufz.de/index.php?en=20939&ufzPublicationIdentifier=26863
Le, A.V., Muehe, E.M., Drabesch, S., Pacheco, J.L., Bayer, T., Joshi, P., Kappler, A., Mansor, M. (2022):
Environmental risk of arsenic mobilization from disposed sand filter materials
Environ. Sci. Technol. 56 (23), 16822 - 16830