Publication Details

Category Text Publication
Reference Category Journals
DOI 10.1021/acs.est.2c04915
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.
Source Titel Environmental Science & Technology
Year 2022
Department UMB
Volume 56
Issue 23
Page From 16822
Page To 16830
Language englisch
Topic T7 Bioeconomy
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
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 10.1021/acs.est.2c04915