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Guo H, Hu T, Yang X, Liu Z, Cui Q, Qu C, Guo F, Liu S, Sweetman AJ, Hou J, Tan W. Roles of varying carbon chains and functional groups of legacy and emerging per-/polyfluoroalkyl substances in adsorption on metal-organic framework: Insights into mechanism and adsorption prediction. Environ Res 2024; 251:118679. [PMID: 38518904 DOI: 10.1016/j.envres.2024.118679] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Revised: 02/21/2024] [Accepted: 03/09/2024] [Indexed: 03/24/2024]
Abstract
Metal-organic frameworks (MOFs) are promising adsorbents for legacy per-/polyfluoroalkyl substances (PFASs), but they are being replaced by emerging PFASs. The effects of varying carbon chains and functional groups of emerging PFASs on their adsorption behavior on MOFs require attention. This study systematically revealed the structure-adsorption relationships and interaction mechanisms of legacy and emerging PFASs on a typical MOF MIL-101(Cr). It also presented an approach reflecting the average electronegativity of PFAS moieties for adsorption prediction. We demonstrated that short-chain or sulfonate PFASs showed higher adsorption capacities (μmol/g) on MIL-101(Cr) than their long-chain or carboxylate counterparts, respectively. Compared with linear PFASs, their branched isomers were found to exhibit a higher adsorption potential on MIL-101(Cr). In addition, the introduction of ether bond into PFAS molecule (e.g., hexafluoropropylene oxide dimeric acid, GenX) increased the adsorption capacity, while the replacement of CF2 moieties in PFAS molecule with CH2 moieties (e.g., 6:2 fluorotelomer sulfonate, 6:2 FTS) caused a decrease in adsorption. Divalent ions (such as Ca2+ and SO42-) and solution pH have a greater effect on the adsorption of PFASs containing ether bonds or more CF2 moieties. PFAS adsorption on MIL-101(Cr) was governed by electrostatic interaction, complexation, hydrogen bonding, π-CF interaction, and π-anion interaction as well as steric effects, which were associated with the molecular electronegativity and chain length of each PFAS. The average electronegativity of individual moieties (named Me) for each PFAS was estimated and found to show a significantly positive correlation with the corresponding adsorption capacity on MIL-101(Cr). The removal rates of major PFASs in contaminated groundwater by MIL-101(Cr) were also correlated with the corresponding Me values. These findings will assist with the adsorption prediction for a wide range of PFASs and contribute to tailoring efficient MOF materials.
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Affiliation(s)
- Hao Guo
- State Environmental Protection Key Laboratory of Soil Health and Green Remediation, College of Resources and Environment, Huazhong Agricultural University, Wuhan 430070, China
| | - Tongyu Hu
- Beijing Construction Engineering Environmental Remediation Co., Ltd., Beijing 100101, China
| | - Xiaoman Yang
- State Environmental Protection Key Laboratory of Soil Health and Green Remediation, College of Resources and Environment, Huazhong Agricultural University, Wuhan 430070, China
| | - Zhaoyang Liu
- State Environmental Protection Key Laboratory of Soil Health and Green Remediation, College of Resources and Environment, Huazhong Agricultural University, Wuhan 430070, China.
| | | | - Chenchen Qu
- State Environmental Protection Key Laboratory of Soil Health and Green Remediation, College of Resources and Environment, Huazhong Agricultural University, Wuhan 430070, China
| | - Fayang Guo
- Institute of Resource and Environment, Henan Polytechnic University, Jiaozuo 454000, China
| | - Shun Liu
- The Seventh Geological Brigade of Hubei Geological Bureau, Yichang 443100, China
| | - Andrew J Sweetman
- Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ, UK
| | - Jingtao Hou
- State Environmental Protection Key Laboratory of Soil Health and Green Remediation, College of Resources and Environment, Huazhong Agricultural University, Wuhan 430070, China
| | - Wenfeng Tan
- State Environmental Protection Key Laboratory of Soil Health and Green Remediation, College of Resources and Environment, Huazhong Agricultural University, Wuhan 430070, China
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Wang Y, Li X, Zheng Z, Shi Y, Cai Y. Chlorinated polyfluoroalkyl ether sulfonic acids in fish, dust, drinking water and human serum: From external exposure to internal doses. Environ Int 2021; 157:106820. [PMID: 34391985 DOI: 10.1016/j.envint.2021.106820] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Revised: 08/02/2021] [Accepted: 08/05/2021] [Indexed: 06/13/2023]
Abstract
Exposure to per- and polyfluoroalkyl substances (PFASs) has raised significant public health concerns due to their persistence and toxicity in the human body. Here, we aimed to investigate the characteristics of exposure to chlorinated polyfluoroalkyl ether sulfonic acids (Cl-PFESAs) and legacy PFASs and the relative contribution from different external pathways to human exposure. Three Cl-PFESAs and fourteen legacy PFASs were detected in human serum, fish, indoor dust and drinking water collected from Shijiazhuang, China. Results showed that 6:2 Cl-PFESA was the third most predominant compound, with an average concentration of 2.70 ng/mL in serum, which was lower than those of perfluorooctane sulfonate (PFOS) and perfluorooctane acid (PFOA) (14.79 and 4.91 ng/mL). The estimated daily intake of 6:2 Cl-PFESA via dust ingestion (mean: 0.008 ng/kg bw/day) was found to be highest among all detected PFASs, while the highest value via fish and drinking water was found for PFOS and PFOA (0.438-9.799 and 0.034-0.155 ng/kg bw/day), respectively. The similar composition of PFASs between serum and fish suggests that fish consumption is a major contributor to human exposure to PFASs. However, the increasing ratios of EDIindoor dust/EDIfish for PFOS, PFOA and 6:2 Cl-PFESA indicated that the contribution of dust ingestion for PFASs, especially 6:2 Cl-PFESA, could not be ignored. The modeled serum concentrations of 6:2 Cl-PFESA higher than its observed levels hint at its gradually increasing exposure levels in the general population. Combined with the lower modeled levels of PFOS than the observed levels, the substituent with 6:2 Cl-PFESA for PFOS is obvious in China. Therefore, further studies on contributions from more detailed external sources and risk assessments of Cl-PFESAs are recommended, especially for some vulnerable subpopulations, considering their widespread exposure and similar environmental behaviors compared with those of their predecessors.
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Affiliation(s)
- Yuan Wang
- College of Environmental Science and Engineering, Hebei University of Science and Technology, Shijiazhuang 050018, China; State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Science, University of Chinese Academy of Sciences, Beijing 100085, China
| | - Xiaotong Li
- College of Environmental Science and Engineering, Hebei University of Science and Technology, Shijiazhuang 050018, China; State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Science, University of Chinese Academy of Sciences, Beijing 100085, China
| | - Zhe Zheng
- Foreign Environmental Cooperation Center of Ministry of Ecology and Environment, Beijing 100035, China
| | - Yali Shi
- School of Environment, Hangzhou Institute for Advanced Study, UCAS, Hangzhou 310024, China; State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Science, University of Chinese Academy of Sciences, Beijing 100085, China.
| | - Yaqi Cai
- School of Environment, Hangzhou Institute for Advanced Study, UCAS, Hangzhou 310024, China; State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Science, University of Chinese Academy of Sciences, Beijing 100085, China
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Zhang B, He Y, Huang Y, Hong D, Yao Y, Wang L, Sun W, Yang B, Huang X, Song S, Bai X, Guo Y, Zhang T, Sun H. Novel and legacy poly- and perfluoroalkyl substances (PFASs) in indoor dust from urban, industrial, and e-waste dismantling areas: The emergence of PFAS alternatives in China. Environ Pollut 2020; 263:114461. [PMID: 32251969 DOI: 10.1016/j.envpol.2020.114461] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Revised: 03/24/2020] [Accepted: 03/24/2020] [Indexed: 05/21/2023]
Abstract
With the phase out of perfluorooctanesulfonate (PFOS) and perfluorooctanoic acid (PFOA), the composition profiles of poly- and perfluoroalkyl substance (PFAS) in our living environment are unclear. In this study, 25 PFASs were analyzed in indoor dust samples collected from urban, industrial, and e-waste dismantling areas in China. PFOS alternatives, including 6:2 chlorinated polyfluorinated ether sulfonate (6:2 Cl-PFESA) (median: 5.52 ng/g) and 8:2 chlorinated polyfluorinated ether sulfonate (8:2 Cl-PFESA) (1.81 ng/g), were frequently detected. By contrast, PFOA alternatives, such as hexafluoropropylene oxide dimer acid (HPFO-DA, Gen-X) and ammonium 4,8-dioxa-3H-perfluorononanoate (ADONA), were not found in any of the dust samples. As expected, all legacy PFASs were widely observed in indoor dust, and 4 PFAS precursors were also detected. Dust concentrations of 6:2 Cl-PFESA were strongly correlated (p < 0.05) with those of 8:2 Cl-PFESA regardless of sampling sites. 6:2 Cl-PFESA was also significantly associated with that of PFOS in industrial and e-waste (p < 0.01) areas. Association analysis suggested that the sources of PFOS and its alternatives are common or related. Although ∑Cl-PFESA concentration was lower than that of PFOS (17.4 ng/g), industrial areas had the highest 6:2 Cl-PFESA/PFOS ratio (0.63). Composition profiles of PFASs in the industrial area showed the forefront of fluorine change. Thus, the present findings suggested that Cl-PFESAs are widely used as PFOS alternatives in China, and high levels of human Cl-PFESA exposure are expected in the future. Short-chain PFASs (C4-C7) were the predominant PFASs found in dust samples, contributing to over 40% of ∑total PFASs. Furthermore, perfluoro-1-butanesulfonate/PFOS and perfluoro-n-butanoic acid (PFBA)/PFOA ratios were 2.8 and 0.72, respectively. These findings suggested shifting to the short-chain PFASs in the environment in China. To the authors knowledge this is the first study to document the levels of 6:2 Cl-PFESA, 8:2 Cl-PFESA in indoor dust.
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Affiliation(s)
- Bo Zhang
- School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou, 510275, China; Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology (Sun Yat-Sen University), Guangzhou, 510275, China
| | - Yuan He
- School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou, 510275, China
| | - Yingyan Huang
- School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou, 510275, China
| | - Danhong Hong
- School of Foreign Languages, Nanfang College of Sun Yat-Sen University, Guangzhou, 510970, China
| | - Yiming Yao
- MOE Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, Tianjin, 300071, China
| | - Lei Wang
- MOE Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, Tianjin, 300071, China
| | | | | | - Xiongfei Huang
- School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou, 510275, China
| | - Shiming Song
- School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou, 510275, China
| | - Xueyuan Bai
- School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou, 510275, China
| | - Yuankai Guo
- School of Chemistry and Environment, Jiaying University, Meizhou, 514015, China
| | - Tao Zhang
- School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou, 510275, China; School of Chemistry and Environment, Jiaying University, Meizhou, 514015, China.
| | - Hongwen Sun
- MOE Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, Tianjin, 300071, China
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Li J, He J, Niu Z, Zhang Y. Legacy per- and polyfluoroalkyl substances (PFASs) and alternatives (short-chain analogues, F-53B, GenX and FC-98) in residential soils of China: Present implications of replacing legacy PFASs. Environ Int 2020; 135:105419. [PMID: 31874352 DOI: 10.1016/j.envint.2019.105419] [Citation(s) in RCA: 84] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2019] [Revised: 12/12/2019] [Accepted: 12/13/2019] [Indexed: 05/27/2023]
Abstract
With the worldwide regulation of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS), the alternatives (short chain analogues and emerging per- and polyfluoroalkyl substances, PFASs) have gradually attracted global attention. This study analysed the replacing of legacy PFASs in China using PFASs data from residential soils, which might be good environmental indicators of their present usage. The total concentrations of 21 PFASs ranged from 244 to 13564 pg/g, and PFOA was the dominant compound among the studied PFASs, with a concentration of 354 ± 439 pg/g. Serious PFASs pollution in residential soils mainly occurred in Eastern Coastal China as a result of locally developed industry and economies. Weak but significant correlations were found between PFASs and environmental and socioeconomic factors, suggesting that various factors determine PFASs contamination in residential soils. The concentration and detection frequency (DF) of short-chain analogues (C < 8) (375 ± 509 pg/g and 100%), and F-53B (216 ± 306 pg/g and 98.9%) were higher than those for PFOS (193 ± 502 pg/g and 85.4%), indicating that these compounds have been widely used as PFOS alternatives and their consumption has already exceeded that of PFOS in China. In addition, GenX (the PFOA alternative) had a concentration and DF of 19.1 ± 104 pg/g and 40.5%, respectively. These values were much lower than those for PFOA (354 ± 439 pg/g and 96.6%), indicating GenX consumption is still limited at the national scale of China, despite its use as a PFOA replacement. Moreover, the low concentration and DF of FC-98 (2.31 ± 11.1 pg/g and 27.0%) indicate that its consumption might be negligible. Our study demonstrated that short chain analogues and emerging alternatives have become the dominant PFAS pollutants in Chinese residential soils, and further studies need to be conducted to understand their toxicity and environmental risks.
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Affiliation(s)
- Jiafu Li
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China
| | - Jiahui He
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China
| | - Zhiguang Niu
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China.
| | - Ying Zhang
- MOE Key Laboratory of Pollution Processes and Environmental Criteria/Tianjin Key Laboratory of Environmental Technology for Complex Trans-Media Pollution, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China.
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