Bio-stabilization of arsenic in sediments by natural carbon-containing biomass: Performance and microbial metabolites

The development of sustainable methods for the control and bio-stabilization of arsenic in sediments, without generating secondary pollution, is an urgent technological need. In this study, we utilized three types of natural carbon-containing biomass (NCCB) to explore the stabilization of arsenic through the synergistic action of native sediment microbiomes. We also examined the metabolic pathways of microorganisms following the introduction of NCCB into high-arsenic sediments, aiming to elucidate the biological processes critical for arsenic bio-stabilization. Our findings indicate that humic acid (HA) and soil organic matter (SOM) are effective in preventing the leaching of As(III) from sediments, while fulvic acid (FA) and SOM can significantly reduce the leaching of As(V). Furthermore, the introduction of NCCB into the system altered the biological metabolic processes, with notable upregulation of metabolites such as 8-hydroxyondansetron, 1,2,3,5,6,8-hexathionane, and citric acid. These results hold promise for the application of these findings in the management of arsenic in natural sediments.