{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,21]],"date-time":"2026-08-21T13:15:36Z","timestamp":1787318136806,"version":"build-2736575974"},"reference-count":50,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2025,8,10]],"date-time":"2025-08-10T00:00:00Z","timestamp":1754784000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Key Technologies Research and Development Program, China","award":["2020YFC1807700"],"award-info":[{"award-number":["2020YFC1807700"]}]},{"name":"Key Technologies Research and Development Program, China","award":["2020ZDK02"],"award-info":[{"award-number":["2020ZDK02"]}]},{"name":"Key Technologies Research and Development Program, China","award":["2021Y01"],"award-info":[{"award-number":["2021Y01"]}]},{"name":"Scientific Research Fund project of Ningde Normal University","award":["2020YFC1807700"],"award-info":[{"award-number":["2020YFC1807700"]}]},{"name":"Scientific Research Fund project of Ningde Normal University","award":["2020ZDK02"],"award-info":[{"award-number":["2020ZDK02"]}]},{"name":"Scientific Research Fund project of Ningde Normal University","award":["2021Y01"],"award-info":[{"award-number":["2021Y01"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Toxics"],"abstract":"<jats:p>Soil co-contamination with antimony (Sb) and arsenic (As) presents significant ecological and human health risks, demanding effective stabilization solutions. This study evaluated iron\u2013manganese-modified hydrochar (FMHC) for synergistic Sb-As stabilization in contaminated smelter soils. Through 60-day natural aging and 30 accelerated aging cycles, we assessed stabilization performance using toxicity leaching tests (acid\/water\/TCLP), bioavailable fraction analysis, bioaccessibility assessment, and Wenzel sequential extraction. The key findings reveal that FMHC (5 wt%) achieves durable stabilization: (1) leaching concentrations remained stable post-aging (Sb: 0.3\u20134.5 mg\u00b7L\u22121, &gt;70% stabilization; As: &lt;0.4 mg\u00b7L\u22121, &gt;94% stabilization); (2) bioavailable fractions showed maximum reductions of 64% (Sb) and 53% (As), though with some fluctuation; and (3) bioaccessible As was consistently reduced (55\u201377%), while Sb exhibited greater variability (maximum 58% reduction). Speciation analysis revealed similar stabilization pathways: Sb stabilization resulted from decreased non-specifically and specifically adsorbed fractions, while As stabilization involved the reduction in non-specifically\/specifically adsorbed and amorphous to poorly crystalline Fe\/Al hydrous oxide-bound fractions. These transformation mechanisms explain FMHC\u2019s superior performance in converting labile Sb\/As into stable forms, offering a sustainable solution for the green remediation of Sb-As co-contaminated soils in mining areas.<\/jats:p>","DOI":"10.3390\/toxics13080674","type":"journal-article","created":{"date-parts":[[2025,8,11]],"date-time":"2025-08-11T09:59:13Z","timestamp":1754906353000},"page":"674","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Iron\u2013Manganese-Modified Hydrochar for Synergistic Stabilization of Antimony and Arsenic in Smelter-Impacted Soils"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1739-7273","authenticated-orcid":false,"given":"Junhuan","family":"Wang","sequence":"first","affiliation":[{"name":"State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yue","family":"Geng","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0007-6109-3465","authenticated-orcid":false,"given":"Hong","family":"Hou","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xianjun","family":"Li","sequence":"additional","affiliation":[{"name":"Fujian Key Laboratory of Toxicant and Drug Toxicology, Medical College, Ningde Normal University, Ningde 352100, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,8,10]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"5467","DOI":"10.1007\/s10653-023-01559-y","article-title":"Pollution characteristics and risk assessment of antimony and arsenic in a typical abandoned antimony smelter","volume":"45","author":"Ren","year":"2023","journal-title":"Environ. 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