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Gao Y, Yang C, Feng G, Zhang BX, Xu ZY, Wang Y, Tleubergenova A, Zhang Y, Meng XZ. Downward migration of per- and polyfluoroalkyl substances (PFAS) in lake sediments: Reconsideration of temporal trend analysis. JOURNAL OF HAZARDOUS MATERIALS 2025; 492:138290. [PMID: 40252315 DOI: 10.1016/j.jhazmat.2025.138290] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2025] [Revised: 04/05/2025] [Accepted: 04/13/2025] [Indexed: 04/21/2025]
Abstract
Using sediment cores to reconstruct the contamination history of per- and polyfluoroalkyl substances (PFAS) is essential for chemical management but poses challenge. Herein, sediment cores, as well as surface water and sediments were taken from two Chinese lakes to investigate the vertical distribution and migration of PFAS. Wind wave, properties of sediment and water, and chemical characters of PFAS were examined to clarify the main factors influencing PFAS migration. Total PFAS concentrations in sediment cores ranged from 0.12 to 5.28 ng g-1 dry weight (dw) in Dianchi Lake and from 0.19 to 2.51 ng g-1 dw in Taihu Lake, respectively. Strong hydrodynamic disturbance (wind-wave erosion depth up to 30 cm) in Taihu Lake resulted in consistent PFAS levels and profiles throughout the sediment core, limiting its use for retrospective analysis. In Dianchi Lake, an increasing trend of total organic carbon-normalized PFAS indicated their persistent emission in China over the past decades. Perfluorooctane sulfonic acid increased markedly from early 2000s; temporal trend in composition for perfluorocarboxylates coincided with the global production transition. Finally, we proposed a three-step conceptual framework, including lake selection, key time point assessment, and contamination history reconstruction, to further improve the reliability of PFAS retrospective analysis in lake.
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Affiliation(s)
- Yunze Gao
- Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Jiaxing University, Jiaxing, Zhejiang 314001, China
| | - Chao Yang
- Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; State Key Laboratory of Water Pollution Control and Green Resource Recycling, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
| | - Ganyu Feng
- Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China
| | - Bo-Xuan Zhang
- Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China
| | - Zi-Yao Xu
- Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China
| | - Ying Wang
- Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China
| | - Akmaral Tleubergenova
- Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China
| | - Yuan Zhang
- Guangdong Provincial Key Laboratory of Water Quality Improvement and Ecological Restoration for Watersheds, School of Ecology, Environment and Resources, Guangdong University of Technology, Guangzhou, Guangdong 510006, China
| | - Xiang-Zhou Meng
- Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China; Jiaxing-Tongji Environmental Research Institute, Jiaxing, Zhejiang 314051, China.
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Wu H, Wang J, Du E, Liu T, Liu M, Guo H, Chu W. Concurrent redox reactions for perfluorocarboxylic acids decontamination via UV-activated tryptophan/carbon nanotubes. WATER RESEARCH 2025; 279:123499. [PMID: 40112736 DOI: 10.1016/j.watres.2025.123499] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2025] [Revised: 02/25/2025] [Accepted: 03/13/2025] [Indexed: 03/22/2025]
Abstract
The contamination and persistence of Perfluorooctanoic Acid (PFOA) in aquatic environments have escalated environmental concerns, driving extensive research into effective decontamination strategies. To enhance the removal efficiency of PFOA via Advanced Reduction Processes (ARP) utilizing UV irradiation of tryptophan (Trp), carbon nanotubes (CNT) were incorporated, resulting in the development of a UV-Trp/CNT system. This novel process demonstrated a significant improvement in PFOA removal kinetics, as well as defluorination and Total Organic Carbon (TOC) reduction, and was effective across a broad spectrum of perfluoroalkyl carboxylic acids (PFCAs). In addition to the advanced reduction mechanism driven by hydrated electrons (eaq-), quenching experiments, material characterization, and chemical calculations indicated that CNTs facilitated the enrichment of Trp and PFOA, enabling electron transfer from PFOA to Trp via the CNT surface. This established a novel reaction pathway for PFOA oxidation coupled with ARP. The sequential defluorination of -CF₂- groups was facilitated by eaq-, while the electron transfer mechanism enabled oxidative decarboxylation, electron rearrangement, CC bond cleavage, and carbon chain shortening. These oxidative and reductive processes alternated systematically, advancing the development of a synergistic redox approach for the removal of PFCAs and inspiring further exploration into the use of carbon materials to construct confined domains and catalyze the degradation of PFASs.
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Affiliation(s)
- Han Wu
- State Key Laboratory of Intelligent Construction and Healthy Operation and Maintenance of Deep Underground Engineering, College of Architecture and Environment, Sichuan University, Chengdu 610065, China; Key Laboratory of Leather Chemistry and Engineering (Sichuan University), Ministry of Education, Chengdu 610065, China
| | - Jingquan Wang
- State Key Laboratory of Intelligent Construction and Healthy Operation and Maintenance of Deep Underground Engineering, College of Architecture and Environment, Sichuan University, Chengdu 610065, China
| | - Erdeng Du
- School of Environmental and Safety Engineering, Changzhou University, Changzhou 213164, China
| | - Tao Liu
- Shimadzu (China) Co., Ltd., Chengdu 610023, China
| | - Min Liu
- State Key Laboratory of Intelligent Construction and Healthy Operation and Maintenance of Deep Underground Engineering, College of Architecture and Environment, Sichuan University, Chengdu 610065, China
| | - Hongguang Guo
- State Key Laboratory of Intelligent Construction and Healthy Operation and Maintenance of Deep Underground Engineering, College of Architecture and Environment, Sichuan University, Chengdu 610065, China; Key Laboratory of Leather Chemistry and Engineering (Sichuan University), Ministry of Education, Chengdu 610065, China.
| | - Wenhai Chu
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
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Xu R, Wang Q, Zha F, Wu J, Sunil Shobha BM, Singh DN. Competitive adsorption and diffusion of methane and vapor-phase per- and polyfluoroalkyl substances in montmorillonite nano pores: Environmental implications. WASTE MANAGEMENT (NEW YORK, N.Y.) 2025; 200:114746. [PMID: 40088804 DOI: 10.1016/j.wasman.2025.114746] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2024] [Revised: 02/10/2025] [Accepted: 03/08/2025] [Indexed: 03/17/2025]
Abstract
Vapor-phase perfluoroalkyl and polyfluoroalkyl substances (PFASs), along with methane emissions from landfills has been key contributors of their atmospheric transport and global distribution. Given the persistence, bioaccumulation, and potential health risks associated with PFAS, understanding their transport behavior in landfill gas barrier is of paramount importance. To gain a deeper understanding of the adsorption and diffusion behavior of vapor-phase PFAS in unsaturated, montmorillonite-rich clay barriers, a molecular dynamics simulation was conducted. A 5-nm montmorillonite nanopore incorporating vapor-phase PFAS (Fluorotelomer alcohol, FTOH), methane, and water molecules was modeled considering the interactions between these species. The results indicate that the presence of methane within the montmorillonite system inhibits the diffusion of both water and FTOH. Additionally, methane competes with FTOH for sorption sites, particularly at low moisture content. At 5 % moisture content, the adsorption density peak of methane is 1.5 times greater than that of FTOH due to stronger van der Waals interactions between methane and montmorillonite. However, as moisture content increases, methane adsorption weakens and becomes more dispersed within the montmorillonite pores. In contrast, FTOH retains a distinct adsorption region at 20 % moisture content, exhibiting a density peak of 0.025 g/cm3 that shifts farther from the montmorillonite surface. At high moisture content, FTOH aggregates due to the hydrophobicity of its C-F tail. These findings provide critical insights into the environmental behavior of volatile PFASs and have important implications for the design and optimization of landfill gas barriers.
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Affiliation(s)
- Rui Xu
- School of Resources and Environmental Engineering, Hefei University of Technology, China
| | - Qiao Wang
- School of Resources and Environmental Engineering, Hefei University of Technology, China.
| | - Fusheng Zha
- School of Resources and Environmental Engineering, Hefei University of Technology, China
| | - Jiawei Wu
- The Architectural Design and Research Institute of Zhejiang University Co. Ltd., 148 Tianmushan Rd., Hangzhou 310058, China
| | | | - Devendra Narain Singh
- Department of Civil Engineering, Indian Institute of Technology Bombay, Mumbai 400076, India
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Lamb BG, Ma B. PFAS self-assembly and adsorption dynamics on graphene: molecular insights into chemical and environmental influences. NANOSCALE 2025; 17:10632-10643. [PMID: 40183688 DOI: 10.1039/d4nr04995k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/05/2025]
Abstract
Per- and polyfluoroalkyl substances (PFAS) are a class of chemicals known for their persistence in the environment due to their amphiphilic nature and the strength of carbon-fluorine bonds. While these properties lead to various industrial and commercial applications including firefighting foams and non-stick coatings, these same characteristics also result in significant environmental and health concerns. This study employs atomistic molecular dynamics (MD) simulations to achieve molecular level insights into PFAS self-assembly and adsorption dynamics, to inform PFAS water remediation. MD simulations of PFAS with different headgroup chemistries and chain lengths on a graphene sorbent surface under varied pH conditions were performed. These simulation results elucidated the impacts of headgroup, chain length, and pH on PFAS adsorption behavior. At neutral pH, PFAS headgroups are fully deprotonated, causing electrostatic repulsions that lead to micelle-like aggregate formation in solution, hindering adsorption. Conversely, at acidic pH, these repulsions are diminished due to protonated headgroups, resulting in higher adsorption percentage with large, stacked aggregates that fully adsorb onto the sorbent. Additionally, chain length notably influenced aggregation, with longer chains forming larger aggregates and achieving more stable adsorption compared to shorter chains. Furthermore, perfluoro-sulfonic acids (PFSAs) displayed stronger adsorption and greater aggregate order than perfluoro-carboxylic acids (PFCAs) in general. These findings underscore the complex interplay between PFAS structure and the dynamics of their adsorption behaviors, as well as the potential of pH as a tuning parameter to enhance PFAS adsorption stability and thereby improve PFAS removal efficiency.
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Affiliation(s)
- Bradley G Lamb
- School of Polymer Science and Engineering, University of Southern Mississippi, 118 College Drive, Hattiesburg, MS 39406, USA.
| | - Boran Ma
- School of Polymer Science and Engineering, University of Southern Mississippi, 118 College Drive, Hattiesburg, MS 39406, USA.
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Xu D, Ding W, Gong X, Tan X, Li H, Li F, Zhang M, Huang Y, Su Y, Cheng HM. Graphene oxide with 1-nm-thick adlayer for efficient and near-instant removal of per- and polyfluoroalkyl substances. Natl Sci Rev 2025; 12:nwaf092. [PMID: 40196394 PMCID: PMC11974386 DOI: 10.1093/nsr/nwaf092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2025] [Revised: 02/25/2025] [Accepted: 03/06/2025] [Indexed: 04/09/2025] Open
Abstract
The environmental occurrence of anthropogenic chemicals-especially persistent micropollutants of per- and polyfluoroalkyl substances (PFAS)-raises pressing concerns for global drinking-water safety. Adsorption is an effective technology for removing PFAS but is limited by unsatisfactory adsorption capacity and efficiency. We report a strategy to attach polyamine adlayers to graphene oxide (GO) nanosheets that produces highly charged and monodispersed 2D adsorbents of a GO nanosheet sandwiched between two 1-nm-thick polyamine adlayers. This adsorbent has a high adsorption capacity for PFAS of ∼3070 mg/g-tens of times greater than that of GO and commercial activated carbon. It also provides almost instant adsorption of a variety of PFAS and reaches 57%-95% of its equilibrium capacity in a minute and removes ∼100% of PFAS from contaminated water sources within a few minutes, transforming real-life PFAS-contaminated water into safe drinking water. Experiment and theory show that the planar nature of the 2D adsorbent combined with its abundant surface adsorption sites that electrostatically attract the polar groups of the PFAS, and hydrogen bonding and hydrophobic-hydrophobic interactions with their non-polar groups, account for its ultra-high adsorption capacity and rapid removal efficiency. We also show that regeneration of the adsorbents removes the adsorbed PFAS and allows subsequent destruction, demonstrating a closed-loop treatment solution for micropollutant contamination.
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Affiliation(s)
- Dingxin Xu
- Institute of Materials Research, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China
| | - Wenhui Ding
- Tsinghua-Berkeley Shenzhen Institute, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China
| | - Xinyu Gong
- Institute of Materials Research, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China
| | - Xianjun Tan
- Tsinghua-Berkeley Shenzhen Institute, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China
| | - Hang Li
- Institute of Materials Research, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China
| | - Fei Li
- Institute of Materials Research, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China
| | - Mingrui Zhang
- Institute of Materials Research, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China
| | - Yuxiong Huang
- Tsinghua-Berkeley Shenzhen Institute, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China
| | - Yang Su
- Institute of Materials Research, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China
| | - Hui-Ming Cheng
- Shenzhen Key Laboratory of Energy Materials for Carbon Neutrality, Institute of Technology for Carbon Neutrality, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
- Faculty of Materials Science and Energy Engineering, Shenzhen Institute of Advanced Technology, Shenzhen 518055, China
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China
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6
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Abeysinghe H, Ma X, Tsige M. PFAS removal via adsorption: A synergistic review on advances of experimental and computational approaches. CHEMOSPHERE 2025; 377:144323. [PMID: 40153986 DOI: 10.1016/j.chemosphere.2025.144323] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2024] [Revised: 03/13/2025] [Accepted: 03/14/2025] [Indexed: 04/01/2025]
Abstract
Per- and polyfluoroalkyl substances (PFAS), commonly known as "forever chemicals", have become a major focus of current research due to their toxicity and persistence in the environment. These synthetic compounds are notoriously difficult to degrade, accumulating in water systems and posing long-term health and environmental risks. Adsorption is one of the most investigated technologies for PFAS removal. This review comprehensively reviewed the PFAS adsorption process, focusing not only on the adsorption itself, but also on the behavior of PFAS in the aquatic environment prior to adsorption because these behaviors directly affect PFAS adsorption. Significantly, this review summarized in detail the advances made in PFAS adsorption from the computational approach and emphasized the importance of integrated experimental and computational studies in gaining molecular-level understanding on the adsorption mechanisms of PFAS. Toward the end, the review identified several critical research gaps and suggested key interdisciplinary research needs for further advancing our understanding on PFAS adsorption.
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Affiliation(s)
- Hansini Abeysinghe
- School of Polymer Science and Polymer Engineering, The University of Akron, Akron, OH, 44325-3909, USA
| | - Xingmao Ma
- Zachry Department of Civil and Environmental Engineering, Texas A&M University, College Station, TX, 77843, USA.
| | - Mesfin Tsige
- School of Polymer Science and Polymer Engineering, The University of Akron, Akron, OH, 44325-3909, USA.
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7
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Ma H, Zhang C, Zhang Z, Zhou Z, Xu Y, Xi M, Zhu K, Jia H. Understanding the structure, distribution, and retention of nanoplastics in montmorillonite nanopore by multi-scale computational simulations. WATER RESEARCH 2025; 282:123638. [PMID: 40239372 DOI: 10.1016/j.watres.2025.123638] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2025] [Revised: 03/27/2025] [Accepted: 04/11/2025] [Indexed: 04/18/2025]
Abstract
The interfacial adsorption, aggregation and deposition processes of nanoplastics (NPs) on clay mineral surfaces critically regulate their environmental mobility, transformation pathways, and ecotoxicological risks in aquatic ecosystems. A quantitative understanding of the nanoscale interfacial processes is essential. This study employs molecular dynamics (MD) simulations and density functional theory (DFT) calculations to elucidate the aggregation and deposition mechanisms of three types of NPs in their pristine and aged states in the nanopore solution of montmorillonite (Mt). In the wet environment, NPs tend to form aggregates in the nanopore and migrate in solution, increasing environmental risk, while in the dry environment, NPs are more likely to deposit on the basal surface to form larger aggregates, consequently reducing their mobility. Results show hydrophobic interactions play as the primary driving force for the aggregation of pristine NPs, and both hydrophilic and hydrophobic interactions contribute to the aggregation of aged NPs. Aged NPs exhibit stronger binding affinity to Mt through mechanism such as Ca²⁺ bridging and hydrogen bonding, compared to their pristine counterparts. DFT calculations further reveal the formation of hydrogen bonds between the hydroxyl groups of aged NPs and the tetrahedral oxygen atoms in Mt. Through atomic-level characterization of interfacial processes, this work establishes a predictive framework for NP environmental behavior by resolving migration dynamics and retention processes in nanopore water.
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Affiliation(s)
- Haozhe Ma
- College of Natural Resources and Environment, Northwest A & F University, Xianyang 712100, China
| | - Chi Zhang
- College of Natural Resources and Environment, Northwest A & F University, Xianyang 712100, China; Key Laboratory of Low-Carbon Green Agriculture in Northwestern China, Ministry of Agriculture and Rural Affairs, Xianyang 712100, China.
| | - Ziheng Zhang
- College of Natural Resources and Environment, Northwest A & F University, Xianyang 712100, China
| | - Zhiyu Zhou
- College of Natural Resources and Environment, Northwest A & F University, Xianyang 712100, China
| | - Yongliang Xu
- College of Natural Resources and Environment, Northwest A & F University, Xianyang 712100, China
| | - Mengning Xi
- College of Natural Resources and Environment, Northwest A & F University, Xianyang 712100, China
| | - Kecheng Zhu
- College of Natural Resources and Environment, Northwest A & F University, Xianyang 712100, China; Key Laboratory of Low-Carbon Green Agriculture in Northwestern China, Ministry of Agriculture and Rural Affairs, Xianyang 712100, China
| | - Hanzhong Jia
- College of Natural Resources and Environment, Northwest A & F University, Xianyang 712100, China; Key Laboratory of Low-Carbon Green Agriculture in Northwestern China, Ministry of Agriculture and Rural Affairs, Xianyang 712100, China
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8
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Müller S, Fiutowski J, Rasmussen MB, Balic Zunic T, Rubahn HG, Posth NR. Nanoplastic in aqueous environments: The role of chemo-electric properties for nanoplastic-mineral interaction. THE SCIENCE OF THE TOTAL ENVIRONMENT 2025; 964:178529. [PMID: 39848159 DOI: 10.1016/j.scitotenv.2025.178529] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2024] [Revised: 01/13/2025] [Accepted: 01/13/2025] [Indexed: 01/25/2025]
Abstract
Due to increasing plastic production, the continuous release of primary and secondary nanoplastic particles (NPs, <1 μm) has become an emerging contaminant in terrestrial environments. The fate and transport of NPs in subsurface environments remain poorly understood, largely due to the complex interplay of mineralogical, chemical, biological, and morphological heterogeneity. This study examines interactions between abundant subsurface minerals and NPs under controlled water chemistry (1 mM KCl, pH 5.5). These conditions minimize potential chemical effects from ions in solution, isolating the impact of mineral complexity. Surface-modified polystyrene nanoparticles (-COOH and -NH2 functional groups) are proxies for degradation products and organic associations found in environmental plastics. Experimental results are compared with theoretical predictions using DLVO (Derjaguin-Landau-Verwey-Overbeek) double-layer force models. Despite all studied minerals maintaining negative surface charges across varying pH, electrostatic double-layer (EDL) interactions played a minor role in NP attachment. Instead, mechanisms such as specific ion-binding interactions (mediated by trace metal ions), bridging via divalent ions, and hydrogen bonding were more significant. Evidence suggests that kinetic effects for most mineral-NP combinations persist beyond 24 h. This study highlights the critical role of biogeochemical and mineralogical composition in controlling NP attachment and release in subsurface environments, with implications for their transport and fate in aquifers.
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Affiliation(s)
- Sascha Müller
- Department of Biology, Functional Ecology, Lund University, Sweden; Department of Geosciences & Natural Resource Management, Geology, University of Copenhagen, Denmark.
| | - Jacek Fiutowski
- Mads Clausen Institute, NanoSYD, University Southern Denmark (SDU), Denmark
| | - Maja Bar Rasmussen
- Department of Geosciences & Natural Resource Management, Geology, University of Copenhagen, Denmark
| | - Tonci Balic Zunic
- Department of Geosciences & Natural Resource Management, Geology, University of Copenhagen, Denmark
| | | | - Nicole R Posth
- Department of Geosciences & Natural Resource Management, Geology, University of Copenhagen, Denmark
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9
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Lemay AC, Bourg IC. Interactions between Per- and Polyfluoroalkyl Substances (PFAS) at the Water-Air Interface. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2025; 59:2201-2210. [PMID: 39836531 DOI: 10.1021/acs.est.4c08285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2025]
Abstract
Per- and polyfluoroalkyl substances (PFAS)─so-called "forever chemicals"─contaminate the drinking water of about 100 million people in the U.S. alone and are inefficiently removed by standard treatment techniques. A key property of these compounds that underlies their fate and transport and the efficacy of several promising remediation approaches is that they accumulate at the water-air interface. This phenomenon remains incompletely understood, particularly under conditions relevant to natural and treatment systems where water-air interfaces often carry significant loads of other organic contaminants or natural organic matter. To understand the impact of organic loading on PFAS adsorption, we carried out molecular dynamics simulations of PFAS at varying interfacial densities. We find that adsorbed PFAS form strong mutual interactions (attraction between perfluoroalkyl chains and electrostatic interactions among charged head groups) that give rise to ordered interfacial coatings. These interactions often involve near-cancellation of hydrophobic attraction and Coulomb repulsion. Our findings explain an apparent paradox whereby PFAS adsorption isotherms often suggest minimal mutual interactions while simultaneously displaying a high sensitivity to the composition and density of interfacial coatings. Consideration of the compounds present with PFAS at the interface has the potential to allow for more accurate predictions of fate and transport and the design of more efficient remediation approaches.
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Affiliation(s)
- Amélie C Lemay
- Department of Civil and Environmental Engineering, Princeton University, Princeton, New Jersey 08544, United States
| | - Ian C Bourg
- Department of Civil and Environmental Engineering, Princeton University, Princeton, New Jersey 08544, United States
- High Meadows Environmental Institute, Princeton University, Princeton, New Jersey 08544, United States
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10
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Choudhary A, Tsunduru A, Tsianou M, Alexandridis P, Bedrov D. Structure, orientation, and dynamics of per- and polyfluoroalkyl substance (PFAS) surfactants at the air-water interface: Molecular-level insights. J Colloid Interface Sci 2025; 679:1207-1218. [PMID: 39426085 DOI: 10.1016/j.jcis.2024.10.041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2024] [Revised: 10/01/2024] [Accepted: 10/07/2024] [Indexed: 10/21/2024]
Abstract
HYPOTHESIS Understanding the intricate molecular-level details of toxic per- and polyfluoroalkyl substances (PFAS) partitioning to the air-water interface holds paramount importance in evaluating their fate and transport, as well as for finding safer alternatives for various applications, including aqueous film forming foams. The behavior of these substances at interfaces strongly depends on molecular architecture, chemistry, and concentration, which define molecular packing, self-assembly, interfacial diffusion, and the surface tension. SIMULATIONS Modeling of three PFAS surfactants, namely, longer-tail (perfluorooctanoate (PFOA)) and shorter-tail (perfluorobutanoate (PFBA) and 2,3,3,3-tetrafluoro-2-(heptafluoropropoxy) propanoate (GenX)) has been conducted using atomistic molecular dynamics simulations. A systematic comparison between these representative PFAS of different sizes and structure reveals factors influencing their association behavior, mechanism of surface tension reduction, and interfacial mobility as a function of surface coverage. FINDINGS Shorter-chain PFAS surfactants (GenX or PFBA) require lower surface coverage compared to longer chain (PFOA) PFAS to achieve the same decrease in surface tension. However, a higher concentration of GenX and PFBA is necessary in the bulk aqueous solution to achieve the same surface coverage as PFOA, due to their higher solubility in water. The PFAS molecular orientation and mobility at the interface are found to be vastly influenced by the length and architecture of the hydrophobic fluorocarbon tail. A significant ordering of the water dipole moment near the anionic headgroup is apparent at high surface concentration. A direct correlation is established between the PFAS interfacial properties and PFAS-PFAS, PFAS-counterion, and PFAS-water interactions.
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Affiliation(s)
- Aditya Choudhary
- Department of Materials Science & Engineering, University of Utah, 122 S. Central Campus Drive, Room 304, Salt Lake City, UT 84112, USA
| | - Aashish Tsunduru
- Department of Materials Science & Engineering, University of Utah, 122 S. Central Campus Drive, Room 304, Salt Lake City, UT 84112, USA
| | - Marina Tsianou
- Department of Chemical and Biological Engineering, University at Buffalo, The State University of New York (SUNY), Buffalo, NY 14260-4200, USA
| | - Paschalis Alexandridis
- Department of Chemical and Biological Engineering, University at Buffalo, The State University of New York (SUNY), Buffalo, NY 14260-4200, USA
| | - Dmitry Bedrov
- Department of Materials Science & Engineering, University of Utah, 122 S. Central Campus Drive, Room 304, Salt Lake City, UT 84112, USA.
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11
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Batikh A, Colombano S, Cochennec M, Davarzani D, Perrault A, Lions J, Grandclément J, Guyonnet D, Togola A, Zornig C, Devau N, Lion F, Alamooti A, Bristeau S, Djemil M, van Hullebusch ED. Mobilization of poly- and perfluoroalkyl substances (PFAS) from heterogeneous soils: Desorption by ethanol/xanthan gum mixture. JOURNAL OF HAZARDOUS MATERIALS 2025; 481:136496. [PMID: 39561539 DOI: 10.1016/j.jhazmat.2024.136496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2024] [Revised: 11/03/2024] [Accepted: 11/11/2024] [Indexed: 11/21/2024]
Abstract
Remediating soils contaminated by per- and polyfluoroalkyl substances (PFAS) is a challenging task due to the unique properties of these compounds, such as variable solubility and resistance to degradation. In-situ soil flushing with solvents has been considered as a remediation technique for PFAS-contaminated soils. The use of non-Newtonian fluids, displaying variable viscosity depending on the applied shear rate, can offer certain advantages in improving the efficiency of the process, particularly in heterogeneous porous media. In this work, the efficacy of ethanol/xanthan mixture (XE) in the recovery of a mixture of perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA), perfluorohexane sulfonate (PFHxS), and perfluorobutane sulfonate (PFBS) from soil has been tested at lab-scale. XE's non-Newtonian behavior was examined through rheological measurements, confirming that ethanol did not affect xanthan gum's (XG) shear-thinning behavior. The recovery of PFAS in batch-desorption exceeded 95 % in ethanol, and 99 % in XE, except for PFBS which reached 94 %. 1D-column experiments revealed overshoots in PFAS breakthrough curves during ethanol and XE injection, due to over-solubilization. XE, (XG 0.05 % w/w) could recover 99 % PFOA, 98 % PFBS, 97 % PFHxS, and 92 % PFOS. Numerical modeling successfully reproduces breakthrough curves for PFOA, PFHxS, and PFBS with the convection-dispersion-sorption equation and Langmuir sorption isotherm.
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Affiliation(s)
- Ali Batikh
- BRGM (French Geological Survey), 3 Avenue Claude Guillemin, Orléans 45100, France; Université Paris Cité, Institut de physique du globe de Paris, CNRS, F-75005 Paris, France; COLAS Environnement, 91, rue de la Folliouse, 01700 Miribel, France.
| | - Stéfan Colombano
- BRGM (French Geological Survey), 3 Avenue Claude Guillemin, Orléans 45100, France
| | - Maxime Cochennec
- BRGM (French Geological Survey), 3 Avenue Claude Guillemin, Orléans 45100, France
| | - Dorian Davarzani
- BRGM (French Geological Survey), 3 Avenue Claude Guillemin, Orléans 45100, France
| | - Arnault Perrault
- COLAS Environnement, 91, rue de la Folliouse, 01700 Miribel, France
| | - Julie Lions
- BRGM (French Geological Survey), 3 Avenue Claude Guillemin, Orléans 45100, France
| | | | - Dominique Guyonnet
- BRGM (French Geological Survey), 3 Avenue Claude Guillemin, Orléans 45100, France
| | - Anne Togola
- BRGM (French Geological Survey), 3 Avenue Claude Guillemin, Orléans 45100, France
| | - Clément Zornig
- BRGM (French Geological Survey), 3 Avenue Claude Guillemin, Orléans 45100, France
| | - Nicolas Devau
- BRGM (French Geological Survey), 3 Avenue Claude Guillemin, Orléans 45100, France
| | - Fabien Lion
- BRGM (French Geological Survey), 3 Avenue Claude Guillemin, Orléans 45100, France
| | - Amir Alamooti
- BRGM (French Geological Survey), 3 Avenue Claude Guillemin, Orléans 45100, France
| | - Sébastien Bristeau
- BRGM (French Geological Survey), 3 Avenue Claude Guillemin, Orléans 45100, France
| | - Mohamed Djemil
- BRGM (French Geological Survey), 3 Avenue Claude Guillemin, Orléans 45100, France
| | - Eric D van Hullebusch
- Université Paris Cité, Institut de physique du globe de Paris, CNRS, F-75005 Paris, France
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12
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Chaudhary A, Usman M, Cheng W, Haderlein S, Boily JF, Hanna K. Heavy-Metal Ions Control on PFAS Adsorption on Goethite in Aquatic Systems. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:20235-20244. [PMID: 39480132 DOI: 10.1021/acs.est.4c10068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/02/2024]
Abstract
Per- and polyfluoroalkyl substances (PFAS) are ubiquitous environmental contaminants that often co-occur with heavy metals. Despite their prevalence, the mobility of PFAS in complex, multicomponent systems, particularly at the molecular scale, remains poorly understood. The vast diversity of PFAS and their low concentrations alongside anthropogenic and natural substances underscore the need for integrating mechanistic insights into the sorption models. This study explores the influence of metal cations (Cu(II), Cd(II), and Fe(II)) on the adsorption of four common PFAS (PFOA, PFOS, PFDA, and GenX) onto goethite (α-FeOOH), a common iron (oxyhydr)oxide in both aquatic and terrestrial environments. PFAS adsorption was highly dependent on the PFAS type, pH, and metal ion concentration, with a surface complexation model effectively predicting these interactions. Cu(II) and Cd(II) enhanced PFOS and PFDA adsorption via ternary complexation while slightly reducing PFOA and GenX adsorption. Under anoxic conditions, Fe(II) significantly increased the adsorption of all PFAS, showing reactivity greater than those of Cu(II) and Cd(II). Additionally, natural organic matter increased PFAS mobility, although metal cations in groundwater may counteract this by enhancing PFAS retention. These findings highlight the key role of metal cations in PFAS transport and offer critical insights for predicting PFAS behavior at oxic-anoxic environmental interfaces.
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Affiliation(s)
- Aaifa Chaudhary
- Ecole Nationale Supérieure de Chimie de Rennes, ISCR-UMR 6226, Université de Rennes, CNRS, F-35000 Rennes, France
- Environmental Mineralogy & Chemistry, Department of Geosciences, University of Tübingen, 72076 Tübingen, Germany
- Department of Environmental Sciences, Government College University, Faisalabad 38000, Pakistan
| | - Muhammad Usman
- Ecole Nationale Supérieure de Chimie de Rennes, ISCR-UMR 6226, Université de Rennes, CNRS, F-35000 Rennes, France
| | - Wei Cheng
- College of Resources and Environmental Science, South-Central Minzu University, Wuhan 430074, P. R. China
| | - Stefan Haderlein
- Environmental Mineralogy & Chemistry, Department of Geosciences, University of Tübingen, 72076 Tübingen, Germany
| | | | - Khalil Hanna
- Ecole Nationale Supérieure de Chimie de Rennes, ISCR-UMR 6226, Université de Rennes, CNRS, F-35000 Rennes, France
- Department of Chemistry, Umeå University, SE-90187 Umeå, Sweden
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13
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Fan C, Cheng L, Deng W. Design of deep eutectic solvents for multiple perfluoroalkyl substances removal: Energy-based screening and mechanism elucidation. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 949:175039. [PMID: 39079639 DOI: 10.1016/j.scitotenv.2024.175039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2024] [Revised: 07/22/2024] [Accepted: 07/23/2024] [Indexed: 08/02/2024]
Abstract
The current landscape of perfluoroalkyl substances (PFAS) extraction methodologies presents significant challenges, particularly for multiple PFAS with different carbon chain lengths. This study introduced an energy-driven strategic approach for screening deep eutectic solvents (DESs) to effectively remove a diverse range of PFAS, including perfluoroalkylcarboxylic acids (PFCAs), perfluoroalkanesulfonic acids (PFSAs), and perfluoroalkyl amides (FAAs), from contaminated environments (total 13 target compounds). Utilizing energy-based screening, we identified DES candidates with high affinity for a spectrum of PFAS compounds from 1234 potential starting materials of eutectic systems. Key findings revealed the superior removal efficiency of tributylphosphineoxide/2-methylpiperazine system, exceeding 99 % for various PFAS with different carbon chain lengths in real environmental water samples. Additionally, we elucidated the molecular interactions between DESs and PFAS through ab initio molecular dynamics (AIMD) simulations, providing valuable insights into the mechanisms governing the removal process. The mechanism of extraction involves hydrogen bond network topology and structural organization, with DESs capable of extracting PFAS while maintaining a weakly aggregated state of target molecules and minimizing the impact on the intrinsic structures of DES. The proposed system forms a dynamic, complementary, and flexible non-covalent interaction network structure with PFAS. The study advances the understanding of DES as a designable, effective, and sustainable alternative to conventional solvents for PFAS remediation, offering a significant contribution to environmental chemistry and green technology.
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Affiliation(s)
- Chen Fan
- School of Light Industry Science and Engineering, Beijing Technology and Business University, Beijing 100048, China.
| | - Linru Cheng
- School of Light Industry Science and Engineering, Beijing Technology and Business University, Beijing 100048, China
| | - Wanlin Deng
- School of Light Industry Science and Engineering, Beijing Technology and Business University, Beijing 100048, China
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14
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Bali S, Hall K, Massoud RI, Almeida NMS, Wilson AK. Interaction of Per- and Polyfluoroalkyl Substances with Estrogen Receptors in Rainbow Trout ( Oncorhynchus mykiss): An In Silico Investigation. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:15960-15970. [PMID: 39207093 PMCID: PMC11394024 DOI: 10.1021/acs.est.4c03648] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2024] [Revised: 07/22/2024] [Accepted: 07/23/2024] [Indexed: 09/04/2024]
Abstract
Fresh water sources, including lakes, such as the Great Lakes, are some of the most important ecosystems in the world. Despite the importance of these lakes, there is increasing concern about the presence of per- and polyfluoroalkyl substances (PFAS)─among the most prevalent contaminants of our time─due to the ability of PFAS to bioaccumulate and persist in the environment, as well as to its linkages to detrimental human and animal health effects. In this study, PFAS exposure on rainbow trout (Oncorhynchus mykiss) is examined at the molecular level, focusing on the impact of PFAS binding on the alpha (α) and beta (β) estrogen receptors (ERs) using molecular dynamics simulations, binding free energy calculations, and structural analysis. ERs are involved in fundamental physiological processes, including reproductive system development, muscle regeneration, and immunity. This study shows that PFAS binds to both the estrogen α and estrogen β receptors, albeit via different binding modes, due to a modification of an amino acid in the binding site as a result of a reorientation of residues in the binding pocket. As ER overactivation can occur through environmental toxins and pollutants, this study provides insights into the influence of different types of PFAS on protein function.
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Affiliation(s)
- Semiha
Kevser Bali
- Department of Chemistry, Michigan
State University, East Lansing, Michigan 48824, United States
| | - Kyleen Hall
- Department of Chemistry, Michigan
State University, East Lansing, Michigan 48824, United States
| | - Rana I. Massoud
- Department of Chemistry, Michigan
State University, East Lansing, Michigan 48824, United States
| | - Nuno M. S. Almeida
- Department of Chemistry, Michigan
State University, East Lansing, Michigan 48824, United States
| | - Angela K. Wilson
- Department of Chemistry, Michigan
State University, East Lansing, Michigan 48824, United States
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15
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Liu ZZ, Pan CG, Peng FJ, Hu JJ, Tan HM, Zhu RG, Zhou CY, Liang H, Yu K. Rapid adsorptive removal of emerging and legacy per- and polyfluoroalkyl substances (PFASs) from water using zinc chloride-modified litchi seed-derived biochar. BIORESOURCE TECHNOLOGY 2024; 408:131157. [PMID: 39059588 DOI: 10.1016/j.biortech.2024.131157] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2024] [Revised: 07/16/2024] [Accepted: 07/23/2024] [Indexed: 07/28/2024]
Abstract
The present study successfully synthesized a novel biochar adsorbent (M-L-BC) using litchi seed modified with zinc chloride for PFASs removal in water. M-L-BC greatly enhanced removal of all examined PFASs (>95 %) as compared to the pristine biochar (<40 %). The maximum adsorption capacity was observed for PFOS, reaching 29.6 mg/g. Adsorption kinetics of PFASs followed the pseudo-second-order model (PSO), suggesting the predominance of chemical adsorption. Moreover, characterization and density functional theory (DFT) calculations jointly revealed involvement of surface complexation, electrostatic interactions, hydrogen bonding, and hydrophobic interactions in PFAS adsorption. Robust PFAS removal was demonstrated for M-L-BC across a wide range of pH (3-9), and coexisting ions had limited impact on adsorption of PFASs except PFBA. Furthermore, M-L-BC showed excellent performance in real water samples and retained reusability after five cycles of regeneration. Overall, M-L-BC represents a promising and high-quality adsorbent for efficient and sustainable removal of PFASs from water.
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Affiliation(s)
- Zhen-Zhu Liu
- School of Resources, Environment and Materials, Guangxi University, Nanning 530004, China; Guangxi Laboratory On the Study of Coral Reefs in the South China Sea, School of Marine Sciences, Guangxi University, Nanning 530004, China
| | - Chang-Gui Pan
- Guangxi Laboratory On the Study of Coral Reefs in the South China Sea, School of Marine Sciences, Guangxi University, Nanning 530004, China.
| | - Feng-Jiao Peng
- SCNU Environmental Research Institute, Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety, MOE Key Laboratory of Theoretical Chemistry of Environment, South China Normal University, Guangzhou 510006, China; School of Environment, South China Normal University, University Town, Guangzhou 510006, China.
| | - Jun-Jie Hu
- Guangxi Laboratory On the Study of Coral Reefs in the South China Sea, School of Marine Sciences, Guangxi University, Nanning 530004, China
| | - Hong-Ming Tan
- School of Resources, Environment and Materials, Guangxi University, Nanning 530004, China; Guangxi Laboratory On the Study of Coral Reefs in the South China Sea, School of Marine Sciences, Guangxi University, Nanning 530004, China
| | - Rong-Gui Zhu
- Guangxi Laboratory On the Study of Coral Reefs in the South China Sea, School of Marine Sciences, Guangxi University, Nanning 530004, China
| | - Chao-Yang Zhou
- Guangxi Laboratory On the Study of Coral Reefs in the South China Sea, School of Marine Sciences, Guangxi University, Nanning 530004, China
| | - Hao Liang
- Guangxi Laboratory On the Study of Coral Reefs in the South China Sea, School of Marine Sciences, Guangxi University, Nanning 530004, China
| | - Kefu Yu
- Guangxi Laboratory On the Study of Coral Reefs in the South China Sea, School of Marine Sciences, Guangxi University, Nanning 530004, China
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16
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Feng Y, You Y, Li M, Guan X, Fu M, Wang C, Xiao Y, He M, Guo H. Mitochondrial DNA copy number mediated the associations between perfluoroalkyl substances and breast cancer incidence: A prospective case-cohort study. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 941:173767. [PMID: 38844220 DOI: 10.1016/j.scitotenv.2024.173767] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2024] [Revised: 05/18/2024] [Accepted: 06/02/2024] [Indexed: 06/10/2024]
Abstract
Epidemiologic studies have reported the relationships between perfluoroalkyl substances (PFASs) and breast cancer incidence, yet the underlying mechanisms are not well understood. This study aimed to elucidate the mediation role of mitochondrial DNA copy number (mtDNAcn) in the relationships between PFASs exposure and breast cancer risk. We conducted a case-cohort study within the Dongfeng-Tongji cohort, involving 226 incident breast cancer cases and a random sub-cohort (n = 990). Their plasma concentrations of six PFASs [including perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), perfluoroheptanoic acid (PFHpA), perfluorooctane sulfonic acid (PFOS) and perfluorohexane sulfonic acid (PFHxS)], and peripheral blood levels of mtDNAcn, were detected at baseline by using ultraperformance liquid chromatography-tandem mass spectrometry and quantitative real-time PCR, respectively. Linear regression and Barlow-weighted Cox models were employed separately to assess the relationships of mtDNAcn with PFASs and breast cancer risk. Mediation analysis was further conducted to quantify the mediating effects of mtDNAcn on PFAS-breast cancer relationships. We observed increased blood mtDNAcn levels among participants with the highest PFNA and PFHpA exposure [Q4 vs. Q1, β(95%CI) = 0.092(0.022, 0.162) and 0.091(0.022, 0.160), respectively], while no significant associations were observed of PFOA, PFDA, PFOS, or PFHxS with mtDNAcn. Compared to participants within the lowest quartile subgroup of mtDNAcn, those with the highest mtDNAcn levels exhibited a significantly increased risk of breast cancer and postmenopausal breast cancer [Q4 vs. Q1, HR(95%CI) = 3.34(1.80, 6.20) and 3.71(1.89, 7.31)]. Furthermore, mtDNAcn could mediate 14.6 % of the PFHpA-breast cancer relationship [Indirect effect, HR(95%CI) = 1.02(1.00, 1.05)]. Our study unveiled the relationships of PFNA and the short-chain PFHpA with mtDNAcn and the mediation role of mtDNAcn in the PFHpA-breast cancer association. These findings provided insights into the potential biological mechanisms linking PFASs to breast cancer risk.
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Affiliation(s)
- Yue Feng
- Department of Occupational and Environmental Health, State Key Laboratory of Environmental Health (Incubating), School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, 13 Hangkong Rd, Wuhan, China; University of New Mexico Comprehensive Cancer Center, Albuquerque, NM, USA
| | - Yingqian You
- Department of Occupational and Environmental Health, State Key Laboratory of Environmental Health (Incubating), School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, 13 Hangkong Rd, Wuhan, China
| | - Mengying Li
- Department of Occupational and Environmental Health, State Key Laboratory of Environmental Health (Incubating), School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, 13 Hangkong Rd, Wuhan, China
| | - Xin Guan
- Department of Occupational and Environmental Health, State Key Laboratory of Environmental Health (Incubating), School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, 13 Hangkong Rd, Wuhan, China
| | - Ming Fu
- Department of Occupational and Environmental Health, State Key Laboratory of Environmental Health (Incubating), School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, 13 Hangkong Rd, Wuhan, China
| | - Chenming Wang
- Department of Occupational and Environmental Health, State Key Laboratory of Environmental Health (Incubating), School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, 13 Hangkong Rd, Wuhan, China
| | - Yang Xiao
- Department of Occupational and Environmental Health, State Key Laboratory of Environmental Health (Incubating), School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, 13 Hangkong Rd, Wuhan, China
| | - Meian He
- Department of Occupational and Environmental Health, State Key Laboratory of Environmental Health (Incubating), School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, 13 Hangkong Rd, Wuhan, China
| | - Huan Guo
- Department of Occupational and Environmental Health, State Key Laboratory of Environmental Health (Incubating), School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, 13 Hangkong Rd, Wuhan, China.
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17
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Cogorno J, Rolle M. Multicomponent and Surface Charge Effects on PFOS Sorption and Transport in Goethite-Coated Porous Media under Variable Hydrochemical Conditions. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:13866-13878. [PMID: 39037862 DOI: 10.1021/acs.est.4c02164] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/24/2024]
Abstract
Perfluorooctanesulfonate (PFOS), a toxic anionic perfluorinated surfactant, exhibits variable electrostatic adsorption mechanisms on charge-regulated minerals depending on solution hydrochemistry. This work explores the interplay of multicomponent interactions and surface charge effects on PFOS adsorption to goethite surfaces under flow-through conditions. We conducted a series of column experiments in saturated goethite-coated porous media subjected to dynamic hydrochemical conditions triggered by step changes in the electrolyte concentration of the injected solutions. Measurements of pH and PFOS breakthrough curves at the outlet allowed tracking the propagation of multicomponent reactive fronts. We performed process-based reactive transport simulations incorporating a mechanistic network of surface complexation reactions to quantitatively interpret the geochemical processes. The experimental and modeling outcomes reveal that the coupled spatio-temporal evolution of pH and electrolyte fronts, driven by the electrostatic properties of the mineral, exerts a key control on PFOS mobility by determining its adsorption and speciation reactions on goethite surfaces. These results illuminate the important influence of multicomponent transport processes and surface charge effects on PFOS mobility, emphasizing the need for mechanistic adsorption models in reactive transport simulations of ionizable PFAS compounds to determine their environmental fate and to perform accurate risk assessment.
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Affiliation(s)
- Jacopo Cogorno
- Department of Environmental and Resource Engineering, Technical University of Denmark, Miljo̷vej, Building 115, Kgs. Lyngby 2800, Denmark
- Sino-Danish College (SDC), University of Chinese Academy of Sciences, Beijing 100049, China
| | - Massimo Rolle
- Department of Environmental and Resource Engineering, Technical University of Denmark, Miljo̷vej, Building 115, Kgs. Lyngby 2800, Denmark
- Institute of Applied Geosciences, Technical University of Darmstadt, Schnittspahnstraße 9, Darmstadt 64287, Germany
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18
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Chen S, Li B, Zhao R, Zhang B, Zhang Y, Chen J, Sun J, Ma X. Natural mineral and industrial solid waste-based adsorbent for perfluorooctanoic acid and perfluorooctane sulfonate removal from surface water: Advances and prospects. CHEMOSPHERE 2024; 362:142662. [PMID: 38936483 DOI: 10.1016/j.chemosphere.2024.142662] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2024] [Revised: 06/14/2024] [Accepted: 06/18/2024] [Indexed: 06/29/2024]
Abstract
PER: and polyfluorinated alkyl substances, especially perfluorooctanoic acid and perfluorooctane sulfonic acid (PFOX), have attracted considerable attention lately because of their widespread occurrence in aquatic environment and potential biological toxicity to animals and human beings. The development of economical, efficient, and engineerable adsorbents for removing PFOX in water has become one of the research focuses. This review summarized the recent progress on natural mineral and industrial solid based adsorbent (NM&ISW-A) and removal mechanisms concerning PFOX onto NM&ISW-A, as well as proposed the current challenges and future perspectives of using NM&ISW-A for PFOX removal in water. Kaolinite and montmorillonite are usually used as model clay minerals for PFOX removal, and have been proved to adsorb PFOX by ligand exchange and electrostatic attraction. Fe-based minerals, such as goethite, magnetite, and hematite, have better PFOX adsorption capacity than clay minerals. The adsorbent prepared from industrial solid waste by high temperature roasting has great potential application prospects. Fabricating nanomaterials, amination modification, surfactant modification, fluorination modification, developing versatile composites, and designing special porous structure are beneficial to improve the adsorption performance of PFOX onto NM&ISW-A by enhancing the specific surface area, positive charge, and hydrophobicity. Electrostatic interaction, hydrophobic interaction, hydrogen bond, ligand and ion exchange, and self-aggregation (formation of micelle or hemimicelle) are the main adsorption mechanisms of PFOX by NM&ISW-A. Among them, electrostatic and hydrophobic interactions play a considerable role in the removal of PFOX by NM&ISW-A. Therefore, NM&ISW-A with electrostatic functionalities and considerable hydrophobic segments enables rapid, efficient, and high-capacity removal of PFOX. The future directions of NM&ISW-A for PFOX removal include the preparation and regeneration of engineerable NM&ISW-A, the development of coupling technology for PFOX removal based on NM&ISW-A, the in-depth research on adsorption mechanism of PFOX by NM&ISW-A, as well as the development of NM&ISW-A for PFOX alternatives removal. This review paper would be helpful the comprehensive understanding of NM&ISW-A potential for PFOX removal and the PFOX removal mechanisms, and identifies the gaps for future research and development.
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Affiliation(s)
- Siyuan Chen
- School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin, 300401, China
| | - Benhang Li
- School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin, 300401, China.
| | - Ruining Zhao
- School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin, 300401, China
| | - Boxuan Zhang
- School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin, 300401, China
| | - Yuqing Zhang
- School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin, 300401, China
| | - Jiale Chen
- School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin, 300401, China
| | - Jiahe Sun
- School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin, 300401, China
| | - Xiaodong Ma
- School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin, 300401, China.
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19
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Sands M, Zhang X, Jensen T, La Frano M, Lin M, Irudayaraj J. PFAS assessment in fish - Samples from Illinois waters. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 927:172357. [PMID: 38614344 DOI: 10.1016/j.scitotenv.2024.172357] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Revised: 03/21/2024] [Accepted: 04/08/2024] [Indexed: 04/15/2024]
Abstract
Per- and Polyfluoroalkyl substances (PFAS) have been widely used in various industries, including pesticide production, electroplating, packaging, paper making, and the manufacturing of water-resistant clothes. This study investigates the levels of PFAS in fish tissues collected from four target waterways (15 sampling points) in the northwestern part of Illinois during 2021-2022. To assess accumulation, concentrations of 17 PFAS compounds were evaluated in nine fish species to potentially inform on exposure risks to local sport fishing population via fish consumption. At least four PFAS (PFHxA, PFHxS, PFOS, and PFBS) were detected at each sampling site. The highest concentrations of PFAS were consistently found in samples from the Rock River, particularly in areas near urban and industrial activities. PFHxA emerged as the most accumulated PFAS in the year 2022, while PFBS and PFOS dominated in 2021. Channel Catfish exhibited the highest PFAS content across different fish species, indicating its bioaccumulation potential across the food chain. Elevated levels of PFOS were observed in nearly all fish, indicating the need for careful consideration of fish consumption. Additional bioaccumulation data in the future years is needed to shed light on the sources and PFAS accumulation potential in aquatic wildlife in relation to exposures for potential health risk assessment.
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Affiliation(s)
- Mia Sands
- Department of Bioengineering, University of Illinois, Urbana-Champaign, Urbana, IL 61801, USA; Biomedical Research Center, Mills Breast Cancer Institute, Carle Foundation Hospital, Urbana, IL, United States
| | - Xing Zhang
- Department of Bioengineering, University of Illinois, Urbana-Champaign, Urbana, IL 61801, USA; Biomedical Research Center, Mills Breast Cancer Institute, Carle Foundation Hospital, Urbana, IL, United States
| | - Tor Jensen
- Cancer Center at Illinois, University of Illinois, Urbana-Champaign, Urbana, IL 61801, USA; Biomedical Research Center, Mills Breast Cancer Institute, Carle Foundation Hospital, Urbana, IL, United States
| | - Michael La Frano
- Roy J. Carver Biotechnology Center, University of Illinois Urbana-Champaign, Urbana, IL 61802, USA
| | - Mindy Lin
- Department of Bioengineering, University of Illinois, Urbana-Champaign, Urbana, IL 61801, USA
| | - Joseph Irudayaraj
- Department of Bioengineering, University of Illinois, Urbana-Champaign, Urbana, IL 61801, USA; Carl Woese Institute for Genomic Biology, University of Illinois, Urbana-Champaign, Urbana, IL 61801, USA; Beckman Institute of Technology, University of Illinois, Urbana-Champaign, Urbana, IL 61801, USA; Cancer Center at Illinois, University of Illinois, Urbana-Champaign, Urbana, IL 61801, USA; Biomedical Research Center, Mills Breast Cancer Institute, Carle Foundation Hospital, Urbana, IL, United States.
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de Souza BB, Meegoda J. Insights into PFAS environmental fate through computational chemistry: A review. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 926:171738. [PMID: 38494023 DOI: 10.1016/j.scitotenv.2024.171738] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2023] [Revised: 02/28/2024] [Accepted: 03/14/2024] [Indexed: 03/19/2024]
Abstract
Per- and polyfluoroalkyl substances (PFAS) are widely used chemicals that exhibit exceptional chemical and thermal stability. However, their resistance to degradation has led to their widespread environmental contamination. PFAS also negatively affect the environment and other organisms, highlighting the need for effective remediation methods to mitigate their presence and prevent further contamination. Computational chemistry methods, such as Density Functional Theory (DFT) and Molecular Dynamics (MD) offer valuable tools for studying PFAS and simulating their interactions with other molecules. This review explores how computational chemistry methods contribute to understanding and tackling PFAS in the environment. PFAS have been extensively studied using DFT and MD, each method offering unique advantages and computational limitations. MD simulates large macromolecules systems however it lacks the ability model chemical reactions, while DFT provides molecular insights however at a high computational cost. The integration of DFT with MD shows promise in predicting PFAS behavior in different environments. This work summarizes reported studies on PFAS compounds, focusing on adsorption, destruction, and bioaccumulation, highlighting contributions of computational methods while discussing the need for continued research. The findings emphasize the importance of computational chemistry in addressing PFAS contamination, guiding risk assessments, and informing future research and innovations in this field.
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Affiliation(s)
- Bruno Bezerra de Souza
- John A. Reif, Jr. Department of Civil and Environmental Engineering, New Jersey Institute of Technology, Newark, NJ 07102, USA
| | - Jay Meegoda
- John A. Reif, Jr. Department of Civil and Environmental Engineering, New Jersey Institute of Technology, Newark, NJ 07102, USA.
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21
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Wang L, Chen L, Wang J, Hou J, Han B, Liu W. Spatial distribution, compositional characteristics, and source apportionment of legacy and novel per- and polyfluoroalkyl substances in farmland soil: A nationwide study in mainland China. JOURNAL OF HAZARDOUS MATERIALS 2024; 470:134238. [PMID: 38608586 DOI: 10.1016/j.jhazmat.2024.134238] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Revised: 04/01/2024] [Accepted: 04/06/2024] [Indexed: 04/14/2024]
Abstract
China, as one of the largest global producers and consumers of per- and poly-fluoroalkyl substances (PFASs), faces concerning levels of PFAS pollution in soil. However, knowledge of their occurrence in agricultural soils of China on the national scale remains unknown. Herein, the first nationwide survey was done by collecting 352 soil samples from 31 provinces in mainland China. The results indicated that the Σ24PFASs concentrations were 74.3 - 24880.0 pg/g, with mean concentrations of PFASs in decreasing order of legacy PFASs > emerging PFASs > PFAS precursors (640.2 pg/g, 340.7 pg/g, and 154.9 pg/g, respectively). The concentrations in coastal eastern China were distinctly higher than those in inland regions. Tianjin was the most severely PFASs-contaminated province because of rapid urban industrialization. This study further compared the PFAS content in monoculture and multiple cropping farmland soils, finding the concentrations of PFASs were high in soils planted with vegetable and fruit monocultures. Moreover, a positive matrix factorization (PMF) model was employed to identify different sources of PFASs. Fluoropolymer industries and aqueous film-forming foams were the primary contributors. The contributions from different emission sources varied across the seven geographical regions. This study provides new baseline data for prevention and control policies for reducing pollution.
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Affiliation(s)
- Lixi Wang
- Key Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China
| | - Liyuan Chen
- Key Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China
| | - Jinze Wang
- Key Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China
| | - Jie Hou
- Key Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China
| | - Bingjun Han
- Key Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China
| | - Wenxin Liu
- Key Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China.
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Kikanme KN, Dennis NM, Orikpete OF, Ewim DRE. PFAS in Nigeria: Identifying data gaps that hinder assessments of ecotoxicological and human health impacts. Heliyon 2024; 10:e29922. [PMID: 38694092 PMCID: PMC11061687 DOI: 10.1016/j.heliyon.2024.e29922] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2024] [Revised: 04/05/2024] [Accepted: 04/17/2024] [Indexed: 05/03/2024] Open
Abstract
This review examines the extensive use and environmental consequences of Per- and Polyfluoroalkyl Substances (PFAS) on a global scale, specifically emphasizing their potential impact in Nigeria. Recognized for their resistance to water and oil, PFAS are under increased scrutiny for their persistent nature and possible ecotoxicological risks. Here, we consolidate existing knowledge on the ecological and human health effects of PFAS in Nigeria, focusing on their neurological effects and the risks they pose to immune system health. We seek to balance the advantages of PFAS with their potential ecological and health hazards, thereby enhancing understanding of PFAS management in Nigeria and advocating for more effective policy interventions and the creation of safer alternatives. The review concludes with several recommendations: strengthening regulatory frameworks, intensifying research into the ecological and health impacts of PFAS, developing new methodologies and longitudinal studies, fostering collaborative efforts for PFAS management, and promoting public awareness and education to support sustainable environmental practices and healthier communities in Nigeria.
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Affiliation(s)
| | - Nicole M. Dennis
- Department of Environmental Sciences, University of California, Riverside, USA
| | - Ochuko Felix Orikpete
- Centre for Occupational Health, Safety and Environment (COHSE), University of Port Harcourt, Choba, Rivers State, Nigeria
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23
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Xiao W, Zhang Y, Chen X, Sha A, Xiong Z, Luo Y, Peng L, Zou L, Zhao C, Li Q. The Diversity and Community Composition of Three Plants' Rhizosphere Fungi in Kaolin Mining Areas. J Fungi (Basel) 2024; 10:306. [PMID: 38786661 PMCID: PMC11121986 DOI: 10.3390/jof10050306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2024] [Revised: 04/10/2024] [Accepted: 04/17/2024] [Indexed: 05/25/2024] Open
Abstract
Mining activities in the kaolin mining area have led to the disruption of the ecological health of the mining area and nearby soils, but the effects on the fungal communities in the rhizosphere soils of the plants are not clear. Three common plants (Conyza bonariensis, Artemisia annua, and Dodonaea viscosa) in kaolin mining areas were selected and analyzed their rhizosphere soil fungal communities using ITS sequencing. The alpha diversity indices (Chao1, Shannon, Simpson, observed-species, pielou-e) of the fungal communities decreased to different extents in different plants compared to the non-kauri mining area. The β-diversity (PCoA, NMDS) analysis showed that the rhizosphere soil fungal communities of the three plants in the kaolin mine area were significantly differentiated from those of the control plants grown in the non-kaolin mine area, and the extent of this differentiation varied among the plants. The analysis of fungal community composition showed that the dominant fungi in the rhizosphere fungi of C. bonariensis and A. annua changed, with an increase in the proportion of Mycosphaerella (genus) by about 20% in C. bonariensis and A. annua. An increase in the proportion of Didymella (genus) by 40% in D. viscosa was observed. At the same time, three plant rhizosphere soils were affected by kaolin mining activities with the appearance of new fungal genera Ochrocladosporium and Plenodomus. Predictive functional potential analysis of the samples revealed that a significant decrease in the potential of functions such as biosynthesis and glycolysis occurred in the rhizosphere fungal communities of kaolin-mined plants compared to non-kaolin-mined areas. The results show that heavy metals and plant species are the key factors influencing these changes, which suggests that selecting plants that can bring more abundant fungi can adapt to heavy metal contamination to restore soil ecology in the kaolin mining area.
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Affiliation(s)
- Wenqi Xiao
- Key Laboratory of Coarse Cereal Processing, Ministry of Agriculture and Rural Affairs, Sichuan Engineering & Technology Research Center of Coarse Cereal Industrialization, School of Food and Biological Engineering, Chengdu University, Chengdu 610106, China; (W.X.); (Y.Z.); (X.C.); (A.S.); (Z.X.); (Y.L.); (L.P.); (L.Z.)
| | - Yunfeng Zhang
- Key Laboratory of Coarse Cereal Processing, Ministry of Agriculture and Rural Affairs, Sichuan Engineering & Technology Research Center of Coarse Cereal Industrialization, School of Food and Biological Engineering, Chengdu University, Chengdu 610106, China; (W.X.); (Y.Z.); (X.C.); (A.S.); (Z.X.); (Y.L.); (L.P.); (L.Z.)
| | - Xiaodie Chen
- Key Laboratory of Coarse Cereal Processing, Ministry of Agriculture and Rural Affairs, Sichuan Engineering & Technology Research Center of Coarse Cereal Industrialization, School of Food and Biological Engineering, Chengdu University, Chengdu 610106, China; (W.X.); (Y.Z.); (X.C.); (A.S.); (Z.X.); (Y.L.); (L.P.); (L.Z.)
| | - Ajia Sha
- Key Laboratory of Coarse Cereal Processing, Ministry of Agriculture and Rural Affairs, Sichuan Engineering & Technology Research Center of Coarse Cereal Industrialization, School of Food and Biological Engineering, Chengdu University, Chengdu 610106, China; (W.X.); (Y.Z.); (X.C.); (A.S.); (Z.X.); (Y.L.); (L.P.); (L.Z.)
| | - Zhuang Xiong
- Key Laboratory of Coarse Cereal Processing, Ministry of Agriculture and Rural Affairs, Sichuan Engineering & Technology Research Center of Coarse Cereal Industrialization, School of Food and Biological Engineering, Chengdu University, Chengdu 610106, China; (W.X.); (Y.Z.); (X.C.); (A.S.); (Z.X.); (Y.L.); (L.P.); (L.Z.)
| | - Yingyong Luo
- Key Laboratory of Coarse Cereal Processing, Ministry of Agriculture and Rural Affairs, Sichuan Engineering & Technology Research Center of Coarse Cereal Industrialization, School of Food and Biological Engineering, Chengdu University, Chengdu 610106, China; (W.X.); (Y.Z.); (X.C.); (A.S.); (Z.X.); (Y.L.); (L.P.); (L.Z.)
| | - Lianxin Peng
- Key Laboratory of Coarse Cereal Processing, Ministry of Agriculture and Rural Affairs, Sichuan Engineering & Technology Research Center of Coarse Cereal Industrialization, School of Food and Biological Engineering, Chengdu University, Chengdu 610106, China; (W.X.); (Y.Z.); (X.C.); (A.S.); (Z.X.); (Y.L.); (L.P.); (L.Z.)
| | - Liang Zou
- Key Laboratory of Coarse Cereal Processing, Ministry of Agriculture and Rural Affairs, Sichuan Engineering & Technology Research Center of Coarse Cereal Industrialization, School of Food and Biological Engineering, Chengdu University, Chengdu 610106, China; (W.X.); (Y.Z.); (X.C.); (A.S.); (Z.X.); (Y.L.); (L.P.); (L.Z.)
| | - Changsong Zhao
- School of Public Health, Chengdu Medical College, Chengdu 610500, China
| | - Qiang Li
- Key Laboratory of Coarse Cereal Processing, Ministry of Agriculture and Rural Affairs, Sichuan Engineering & Technology Research Center of Coarse Cereal Industrialization, School of Food and Biological Engineering, Chengdu University, Chengdu 610106, China; (W.X.); (Y.Z.); (X.C.); (A.S.); (Z.X.); (Y.L.); (L.P.); (L.Z.)
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24
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Bui TH, Zuverza-Mena N, Dimkpa CO, Nason SL, Thomas S, White JC. PFAS remediation in soil: An evaluation of carbon-based materials for contaminant sequestration. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2024; 344:123335. [PMID: 38211874 PMCID: PMC10922530 DOI: 10.1016/j.envpol.2024.123335] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Revised: 12/19/2023] [Accepted: 01/08/2024] [Indexed: 01/13/2024]
Abstract
The presence of per- and poly-fluoroalkyl substances (PFAS) in soils is a global concern as these emerging contaminants are highly resistant to degradation and cause adverse effects on human and environmental health at very low concentrations. Sequestering PFAS in soils using carbon-based materials is a low-cost and effective strategy to minimize pollutant bioavailability and exposure, and may offer potential long-term remediation of PFAS in the environment. This paper provides a comprehensive evaluation of current insights on sequestration of PFAS in soil using carbon-based sorbents. Hydrophobic effects originating from fluorinated carbon (C-F) backbone "tail" and electrostatic interactions deriving from functional groups on the molecules' "head" are the two driving forces governing PFAS sorption. Consequently, varying C-F chain lengths and polar functional groups significantly alter PFAS availability and leachability. Furthermore, matrix parameters such as soil organic matter, inorganic minerals, and pH significantly impact PFAS sequestration by sorbent amendments. Materials such as activated carbon, biochar, carbon nanotubes, and their composites are the primary C-based materials used for PFAS adsorption. Importantly, modifying the carbon structural and surface chemistry is essential for increasing the active sorption sites and for strengthening interactions with PFAS. This review evaluates current literature, identifies knowledge gaps in current remediation technologies and addresses future strategies on the sequestration of PFAS in contaminated soil using sustainable novel C-based sorbents.
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Affiliation(s)
- Trung Huu Bui
- The Connecticut Agricultural Experiment Station, 123 Huntington Street, New Haven, CT, 06511, USA
| | - Nubia Zuverza-Mena
- The Connecticut Agricultural Experiment Station, 123 Huntington Street, New Haven, CT, 06511, USA
| | - Christian O Dimkpa
- The Connecticut Agricultural Experiment Station, 123 Huntington Street, New Haven, CT, 06511, USA
| | - Sara L Nason
- The Connecticut Agricultural Experiment Station, 123 Huntington Street, New Haven, CT, 06511, USA
| | - Sara Thomas
- The Connecticut Agricultural Experiment Station, 123 Huntington Street, New Haven, CT, 06511, USA
| | - Jason C White
- The Connecticut Agricultural Experiment Station, 123 Huntington Street, New Haven, CT, 06511, USA.
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25
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Chu C, Ma LL, Alawi H, Ma W, Zhu Y, Sun J, Lu Y, Xue Y, Chen G. Mechanistic exploration of polytetrafluoroethylene thermal plasma gasification through multiscale simulation coupled with experimental validation. Nat Commun 2024; 15:1654. [PMID: 38395949 PMCID: PMC10891128 DOI: 10.1038/s41467-024-45077-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Accepted: 01/15/2024] [Indexed: 02/25/2024] Open
Abstract
The ever-growing quantities of persistent Polytetrafluoroethylene (PTFE) wastes, along with consequential ecological and human health concerns, stimulate the need for alternative PTFE disposal method. The central research challenge lies in elucidating the decomposition mechanism of PTFE during high-temperature waste treatment. Here, we propose the PTFE microscopic thermal decomposition pathways by integrating plasma gasification experiments with multi-scale simulations strategies. Molecular dynamic simulations reveal a pyrolysis-oxidation & chain-shortening-deep defluorination (POCD) degradation pathway in an oxygen atmosphere, and an F abstraction-hydrolysis-deep defluorination (FHD) pathway in a steam atmosphere. Density functional theory computations demonstrate the vital roles of 1O2 and ·H radicals in the scission of PTFE carbon skeleton, validating the proposed pathways. Experimental results confirm the simulation results and show that up to 80.12% of gaseous fluorine can be recovered through plasma gasification within 5 min, under the optimized operating conditions determined through response surface methodology.
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Affiliation(s)
- Chu Chu
- School of Environmental Science and Engineering, Tianjin University/Tianjin Key Lab of Biomass/Wastes Utilization, Tianjin, 300072, China
| | - Long Long Ma
- School of Energy &Environment, Key Lab Energy Thermal Conversion & Control, Southeast University, Nanjing, 210096, China
| | - Hyder Alawi
- School of Environmental Science and Engineering, Tianjin University/Tianjin Key Lab of Biomass/Wastes Utilization, Tianjin, 300072, China
| | - Wenchao Ma
- School of Environmental Science and Engineering, Tianjin University/Tianjin Key Lab of Biomass/Wastes Utilization, Tianjin, 300072, China.
| | - YiFei Zhu
- School of Electrical Engineering, Xi'an Jiaotong University, Xi'an, 710049, China
| | - Junhao Sun
- Postdoctoral Programme, Guosen Securities, Shenzhen, 518001, China
| | - Yao Lu
- School of Chemical Engineering and Technology, Hebei University of Technology, Tianjin, 300401, China
| | - Yixian Xue
- School of Environmental Science and Engineering, Tianjin University/Tianjin Key Lab of Biomass/Wastes Utilization, Tianjin, 300072, China
| | - Guanyi Chen
- School of Environmental Science and Engineering, Tianjin University/Tianjin Key Lab of Biomass/Wastes Utilization, Tianjin, 300072, China
- School of Ecology and Environment, Tibet University, Lhasa, 850012, Tibet, China
- School of Mechanical Engineering, Tianjin University of Commerce, Tianjin, 300314, China
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26
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Xue Q, Jiao Z, Pan W, Liu X, Fu J, Zhang A. Multiscale computational simulation of pollutant behavior at water interfaces. WATER RESEARCH 2024; 250:121043. [PMID: 38154340 DOI: 10.1016/j.watres.2023.121043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2023] [Revised: 12/12/2023] [Accepted: 12/18/2023] [Indexed: 12/30/2023]
Abstract
The investigation of pollutant behavior at water interfaces is critical to understand pollution in aquatic systems. Computational methods allow us to overcome the limitations of experimental analysis, delivering valuable insights into the chemical mechanisms and structural characteristics of pollutant behavior at interfaces across a range of scales, from microscopic to mesoscopic. Quantum mechanics, all-atom molecular dynamics simulations, coarse-grained molecular dynamics simulations, and dissipative particle dynamics simulations represent diverse molecular interaction calculation methods that can effectively model pollutant behavior at environmental interfaces from atomic to mesoscopic scales. These methods provide a rich variety of information on pollutant interactions with water surfaces. This review synthesizes the advancements in applying typical computational methods to the formation, adsorption, binding, and catalytic conversion of pollutants at water interfaces. By drawing on recent advancements, we critically examine the current challenges and offer our perspective on future directions. This review seeks to advance our understanding of computational techniques for elucidating pollutant behavior at water interfaces, a critical aspect of water research.
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Affiliation(s)
- Qiao Xue
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Zhiyue Jiao
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Wenxiao Pan
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Xian Liu
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Jianjie Fu
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; School of Environment, Hangzhou Institute for Advanced Study, UCAS, Hangzhou 310024, China; Institute of Environment and Health, Jianghan University, Wuhan 430056, China.
| | - Aiqian Zhang
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China; School of Environment, Hangzhou Institute for Advanced Study, UCAS, Hangzhou 310024, China; Institute of Environment and Health, Jianghan University, Wuhan 430056, China.
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27
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Schumacher BA, Zimmerman JH, Williams AC, Lutes CC, Holton CW, Escobar E, Hayes H, Warrier R. Distribution of select per- and polyfluoroalkyl substances at a chemical manufacturing plant. JOURNAL OF HAZARDOUS MATERIALS 2024; 464:133025. [PMID: 37995636 PMCID: PMC10734402 DOI: 10.1016/j.jhazmat.2023.133025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Revised: 11/14/2023] [Accepted: 11/15/2023] [Indexed: 11/25/2023]
Abstract
Per- and polyfluoroalkyl substances (PFAS) are used in various industrial products; however, they pose serious health risks. In this study, soil, soil gas, and groundwater samples were collected at a PFAS manufacturing facility in New Jersey, USA, to determine the presence and distribution of PFASs from the soil surface to groundwater and at various distances from the presumed source. Fluorotelomer alcohols (FTOHs) were detected in soil (< 0.26-36.15 ng/g) and soil gas (160-12,000 E µg/m3), while perfluorinated carboxylic acids (PFCAs) were found in soil (4.3-810 ng/g), soil gas (<0.10-180 µg/m3), and groundwater (37-49 µg/L). FTOH and PFCA concentrations decreased as the distance from the presumed source increased, suggesting that PFCAs are likely to migrate in groundwater, whereas FTOHs primarily move in the vapor phase. The presence of PFAS in the groundwater, soil, and soil gas samples indicate its potential for vapor intrusion; thus, some PFAS may contribute to indoor air inhalation exposure. To the best of our knowledge, this is the first report on the quantification of volatile PFAS in soil gas at a PFAS manufacturing facility.
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Affiliation(s)
- Brian A Schumacher
- US EPA Office of Research and Development (ORD), Center for Environmental Measurement & Modeling, 960 College Station Road, Athens, GA 30605, USA.
| | - John H Zimmerman
- US EPA ORD, Center for Environmental Measurement & Modeling, 109 T.W. Alexander Drive, Research Triangle Park, NC 27711, USA
| | - Alan C Williams
- US EPA ORD, Center for Environmental Measurement & Modeling, 109 T.W. Alexander Drive, Research Triangle Park, NC 27711, USA
| | | | - Chase W Holton
- Geosyntec Consultants, 5670 Greenwood Plaza Blvd, Greenwood Village, CO 80111, USA
| | - Elsy Escobar
- Jacobs, 2001 Market Street, Suite 900, Philadelphia, PA 19103, USA
| | - Heidi Hayes
- Eurofins Air Toxics, LLC, 180 Blue Ravine Road, Suite B, Folsom, CA 95630, USA
| | - Rohit Warrier
- Research Triangle Institute, International, 3040 East Cornwallis Road, Research Triangle Park, NC 27709, USA
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28
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Sookhak Lari K, Davis GB, Kumar A, Rayner JL, Kong XZ, Saar MO. The Dynamics of Per- and Polyfluoroalkyl Substances (PFAS) at Interfaces in Porous Media: A Computational Roadmap from Nanoscale Molecular Dynamics Simulation to Macroscale Modeling. ACS OMEGA 2024; 9:5193-5202. [PMID: 38343928 PMCID: PMC10851370 DOI: 10.1021/acsomega.3c09201] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2023] [Revised: 12/11/2023] [Accepted: 12/21/2023] [Indexed: 02/04/2025]
Abstract
Managing and remediating perfluoroalkyl and polyfluoroalkyl substance (PFAS) contaminated sites remains challenging. The major reasons are the complexity of geological media, partly unknown dynamics of the PFAS in different phases and at fluid-fluid and fluid-solid interfaces, and the presence of cocontaminants such as nonaqueous phase liquids (NAPLs). Critical knowledge gaps exist in understanding the behavior and fate of PFAS in vadose and saturated zones and in other porous media such as concrete and asphalt. The complexity of PFAS-surface interactions warrants the use of advanced characterization and computational tools to understand and quantify nanoscale behavior of the molecules. This can then be upscaled to the microscale to develop a constitutive relationship, in particular to distinguish between surface and bulk diffusion. The dominance of surface diffusion compared to bulk diffusion results in the solutocapillary Marangoni effect, which has not been considered while investigating the fate of PFAS. Without a deep understanding of these phenomena, derivation of constitutive relationships is challenging. The current Darcy scale mass-transfer models use constitutive relationships derived from either experiments or field measurements, which makes their applicability potentially limited. Here we review current efforts and propose a roadmap for developing Darcy scale transport equations for PFAS. We find that this needs to be based on systematic upscaling of both experimental and computational studies from nano- to microscales. We highlight recent efforts to undertake molecular dynamics simulations on problems with similar levels of complexity and explore the feasibility of conducting nanoscale simulations on PFAS dynamics at the interface of fluid pairs.
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Affiliation(s)
- Kaveh Sookhak Lari
- CSIRO Environment, Private Bag No. 5, Wembley, WA 6913, Australia
- Department of Earth Sciences, Geothermal Energy and Geofluids Group, ETH Zurich CH-8092, Switzerland
| | - Greg B Davis
- CSIRO Environment, Private Bag No. 5, Wembley, WA 6913, Australia
| | - Anand Kumar
- CSIRO Environment, Private Bag No. 5, Wembley, WA 6913, Australia
| | - John L Rayner
- CSIRO Environment, Private Bag No. 5, Wembley, WA 6913, Australia
| | - Xiang-Zhao Kong
- Department of Earth Sciences, Geothermal Energy and Geofluids Group, ETH Zurich CH-8092, Switzerland
| | - Martin O Saar
- Department of Earth Sciences, Geothermal Energy and Geofluids Group, ETH Zurich CH-8092, Switzerland
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29
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Cogorno J, Rolle M. Impact of Variable Water Chemistry on PFOS-Goethite Interactions: Experimental Evidence and Surface Complexation Modeling. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:1731-1740. [PMID: 38206803 DOI: 10.1021/acs.est.3c09501] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/13/2024]
Abstract
Perfluorooctanesulfonate (PFOS) has become a major concern due to its widespread occurrence in the environment and severe toxic effects. In this study, we investigate PFOS sorption on goethite surfaces under different water chemistry conditions to understand the impact of variable groundwater chemistry. Our investigation is based on multiple lines of evidence, including (i) a series of sorption experiments with varying pH, ionic strength, and PFOS initial concentration, (ii) IR spectroscopy analysis, and (iii) surface complexation modeling. PFOS was found to bind to goethite through a strong hydrogen-bonded (HB) complex and a weaker outer-sphere complex involving Na+ coadsorption (OS-Na+). The pH and ionic strength of the solution had a nontrivial impact on the speciation and coexistence of these surface complexes. Acidic conditions and low ionic strength promoted hydrogen bonding between the sulfonate headgroup and protonated hydroxo surface sites. Higher electrolyte concentrations and pH values hindered the formation of strong hydrogen bonds upon the formation of a ternary PFOS-Na+-goethite outer-sphere complex. The findings of this study illuminate the key control of variable solution chemistry on PFOS adsorption to mineral surfaces and the importance to develop surface complexation models integrating mechanistic insights for the accurate prediction of PFOS mobility and environmental fate.
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Affiliation(s)
- Jacopo Cogorno
- Department of Environmental and Resource Engineering, Technical University of Denmark, Miljøvej, Building 115, 2800 Kgs. Lyngby, Denmark
- Sino-Danish College (SDC), University of Chinese Academy of Sciences, Beijing 100049, China
| | - Massimo Rolle
- Department of Environmental and Resource Engineering, Technical University of Denmark, Miljøvej, Building 115, 2800 Kgs. Lyngby, Denmark
- Institute of Applied Geosciences, Technical University of Darmstadt, Schnittspahnstraße 9, 64287 Darmstadt, Germany
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30
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Cai W, Navarro DA, Du J, Srivastava P, Cao Z, Ying G, Kookana RS. Effect of heavy metal co-contaminants on the sorption of thirteen anionic per- and poly-fluoroalkyl substances (PFAS) in soils. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 905:167188. [PMID: 37734606 DOI: 10.1016/j.scitotenv.2023.167188] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2023] [Revised: 09/13/2023] [Accepted: 09/16/2023] [Indexed: 09/23/2023]
Abstract
Understanding the sorption behavior of per- and poly-fluoroalkyl substances (PFAS) in soils are essential for assessing their mobility and risk in the environment. Heavy metals often coexist with PFAS depending on the source and history of contamination. In this study, we investigated the effect of heavy metal co-contaminants (Pb2+, Cu2+ and Zn2+) on the sorption of 13 anionic PFAS with different perfluorocarbon chain length (C3-C9) in two soils with different properties. Results revealed that Pb2+, Cu2+ and Zn2+ had little effect on the sorption of most short-chain compounds, while the presence of these heavy metals enhanced the sorption of long-chain PFAS in two soils. The distribution coefficients (Kd) of several long-chain PFAS linearly increased with increasing concentrations of heavy metal, especially in the presence of Pb2+ (ΔKd/Δ [Pb2+] > 3 for PFOS and PFNA vs <1 for PFPeS and PFHxS). While several mechanisms may have contributed to the enhancement of sorption of PFAS, the heavy metals most likely contributed through enhanced hydrophobic interactions of PFAS by neutralizing the negative charge of adsorption surfaces in soils and thus making it more favorable for their partitioning onto the solid phase. Moreover, the increase in the concentrations of heavy metals led to a decrease in the pH of the system and promoted sorption of long-chain compounds, especially in soil with lower organic carbon content. Overall, this study provides evidence that the presence of co-existing heavy metal cations in soils can significantly enhance the sorption of long-chain PFAS onto soil, thereby potentially limiting their mobility in the environment.
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Affiliation(s)
- Wenwen Cai
- School of Environment, Key Laboratory for Yellow River and Huai River Water Environment and Pollution Control, Ministry of Education, Henan Key Laboratory for Environmental Pollution Control, International Joint Laboratory on Key Techniques in Water Treatment, Henan Normal University, Xinxiang 453007, China; State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Divina A Navarro
- CSIRO Environment, Locked Bag 2, Glen Osmond, 5064, Australia; School of Agriculture, Food and Wine, The University of Adelaide, Waite Campus, Locked Bag 1, Glen Osmond 5064, Australia.
| | - Jun Du
- CSIRO Environment, Locked Bag 2, Glen Osmond, 5064, Australia
| | | | - Zhiguo Cao
- School of Environment, Key Laboratory for Yellow River and Huai River Water Environment and Pollution Control, Ministry of Education, Henan Key Laboratory for Environmental Pollution Control, International Joint Laboratory on Key Techniques in Water Treatment, Henan Normal University, Xinxiang 453007, China
| | - Guangguo Ying
- School of Environment, South China Normal University, Guangzhou 510006, China
| | - Rai S Kookana
- CSIRO Environment, Locked Bag 2, Glen Osmond, 5064, Australia; School of Agriculture, Food and Wine, The University of Adelaide, Waite Campus, Locked Bag 1, Glen Osmond 5064, Australia
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31
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Almeida NMS, Bali SK, James D, Wang C, Wilson AK. Binding of Per- and Polyfluoroalkyl Substances (PFAS) to the PPARγ/RXRα-DNA Complex. J Chem Inf Model 2023; 63:7423-7443. [PMID: 37990410 DOI: 10.1021/acs.jcim.3c01384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2023]
Abstract
Nuclear receptors are the fundamental building blocks of gene expression regulation and the focus of many drug targets. While binding to DNA, nuclear receptors act as transcription factors, governing a multitude of functions in the human body. Peroxisome proliferator-activator receptor γ (PPARγ) and the retinoid X receptor α (RXRα) form heterodimers with unique properties and have a primordial role in insulin sensitization. This PPARγ/RXRα heterodimer has been shown to be impacted by per- and polyfluoroalkyl substances (PFAS) and linked to a variety of significant health conditions in humans. Herein, a selection of the most common PFAS (legacy and emerging) was studied utilizing molecular dynamics simulations for PPARγ/RXRα. The local and global structural effects of PFAS binding on the known ligand binding pockets of PPARγ and RXRα as well as the DNA binding domain (DBD) of RXRα were inspected. The binding free energies were predicted computationally and were compared between the different binding pockets. In addition, two electronic structure approaches were utilized to model the interaction of PFAS within the DNA binding domain, density functional theory (DFT) and domain-based pair natural orbital coupled cluster with perturbative triples (DLPNO-CCSD(T)) approaches, with implicit solvation. Residue decomposition and hydrogen-bonding analysis were also performed, detailing the role of prominent residues in molecular recognition. The role of l-carnitine is explored as a potential in vivo remediation strategy for PFAS interaction with the PPARγ/RXRα heterodimer. In this work, it was found that PFAS can bind and act as agonists for all of the investigated pockets. For the first time in the literature, PFAS are postulated to bind to the DNA binding domain in a nonspecific manner. In addition, for the PPARγ ligand binding domain, l-carnitine shows promise in replacing smaller PFAS from the pocket.
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Affiliation(s)
- Nuno M S Almeida
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48864, United States
| | - Semiha Kevser Bali
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48864, United States
| | - Deepak James
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48864, United States
| | - Cong Wang
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48864, United States
| | - Angela K Wilson
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48864, United States
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32
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Siegel HG, Nason SL, Warren JL, Prunas O, Deziel NC, Saiers JE. Investigation of Sources of Fluorinated Compounds in Private Water Supplies in an Oil and Gas-Producing Region of Northern West Virginia. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:17452-17464. [PMID: 37923386 PMCID: PMC10653085 DOI: 10.1021/acs.est.3c05192] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Revised: 10/20/2023] [Accepted: 10/25/2023] [Indexed: 11/07/2023]
Abstract
Per- and polyfluoroalkyl substances (PFASs) are a class of toxic organic compounds that have been widely used in consumer applications and industrial activities, including oil and gas production. We measured PFAS concentrations in 45 private wells and 8 surface water sources in the oil and gas-producing Doddridge, Marshall, Ritchie, Tyler, and Wetzel Counties of northern West Virginia and investigated relationships between potential PFAS sources and drinking water receptors. All surface water samples and 60% of the water wells sampled contained quantifiable levels of at least one targeted PFAS compound, and four wells (8%) had concentrations above the proposed maximum contaminant level (MCL) for perfluorooctanoic acid (PFOA). Individual concentrations of PFOA and perfluorobutanesulfonic acid exceeded those measured in finished public water supplies. Total targeted PFAS concentrations ranged from nondetect to 36.8 ng/L, with surface water concentrations averaging 4-fold greater than groundwater. Semiquantitative, nontargeted analysis showed concentrations of emergent PFAS that were potentially higher than targeted PFAS. Results from a multivariate latent variable hierarchical Bayesian model were combined with insights from analyses of groundwater chemistry, topographic characteristics, and proximity to potential PFAS point sources to elucidate predictors of PFAS concentrations in private wells. Model results reveal (i) an increased vulnerability to contamination in upland recharge zones, (ii) geochemical controls on PFAS transport likely driven by adsorption, and (iii) possible influence from nearby point sources.
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Affiliation(s)
- Helen G. Siegel
- School
of the Environment, Yale University, 195 Prospect Street, New Haven, Connecticut 06511, United States
| | - Sara L. Nason
- Connecticut
Agricultural Experiment Station, 123 Huntington Street, New
Haven, Connecticut 06504, United States
| | - Joshua L. Warren
- School
of Public Health, Yale University, 60 College Street, New Haven, Connecticut 06510, United States
| | - Ottavia Prunas
- Swiss
Tropical and Public Health Institute, 2 Kreuzstrasse, Allschwill, Basel 4123, Switzerland
| | - Nicole C. Deziel
- School
of Public Health, Yale University, 60 College Street, New Haven, Connecticut 06510, United States
| | - James E. Saiers
- School
of the Environment, Yale University, 195 Prospect Street, New Haven, Connecticut 06511, United States
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33
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Tan HM, Pan CG, Yin C, Yu K. Toward systematic understanding of adsorptive removal of legacy and emerging per-and polyfluoroalkyl substances (PFASs) by various activated carbons (ACs). ENVIRONMENTAL RESEARCH 2023; 233:116495. [PMID: 37364627 DOI: 10.1016/j.envres.2023.116495] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Revised: 06/12/2023] [Accepted: 06/22/2023] [Indexed: 06/28/2023]
Abstract
Per-and polyfluoroalkyl substances (PFASs) have received great attention due to their persistence, bioaccumulation and toxicity. Various activated carbons (ACs) exhibit wide variability in adsorptive performance towards PFASs. In order to gain a systematic understanding of adsorptive removal of legacy and emerging PFASs by ACs, the adsorption of ten PFASs on various ACs was comprehensively investigated. Results showed that granular activated carbon-1 (GAC-1) and powdered activated carbon-1 (PAC-1) removed more than 90% of all target PFASs. Particle size, surface charge, and micropores quantity of ACs were closely related to their performance for PFASs removal. Electrostatic interaction, hydrophobic interaction, surface complexation and hydrogen bonding were the adsorption mechanisms, with hydrophobic interaction being the predominant adsorptive force. Physical and chemical adsorption were both involved in PFAS adsorption. The removal rates of PFASs by GAC-1 decreased from 93%-100% to 15%-66% in the presence of 5 mg/L fulvic acid (FA). GAC was able to remove more PFASs under acidic medium, whereas PAC removed hydrophobic PFASs better under the neutral medium. The removal rates of PFASs by GAC-3 increased significantly from 0%-21% to 52%-97% after being impregnated with benzalkonium chlorides (BACs), demonstrating the superiority of this modification method. Overall, this study provided theoretical support for removing PFASs from water phase with ACs.
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Affiliation(s)
- Hong-Ming Tan
- Guangxi Laboratory on the Study of Coral Reefs in the South China Sea, School of Marine Sciences, Guangxi University, Nanning, 530004, China; School of Resources, Environment and Materials, Guangxi University, Nanning, 530004, China
| | - Chang-Gui Pan
- Guangxi Laboratory on the Study of Coral Reefs in the South China Sea, School of Marine Sciences, Guangxi University, Nanning, 530004, China; Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, China.
| | - Chao Yin
- Guangxi Laboratory on the Study of Coral Reefs in the South China Sea, School of Marine Sciences, Guangxi University, Nanning, 530004, China
| | - Kefu Yu
- Guangxi Laboratory on the Study of Coral Reefs in the South China Sea, School of Marine Sciences, Guangxi University, Nanning, 530004, China; Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, China
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34
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Shi Y, Mu H, You J, Han C, Cheng H, Wang J, Hu H, Ren H. Confined water-encapsulated activated carbon for capturing short-chain perfluoroalkyl and polyfluoroalkyl substances from drinking water. Proc Natl Acad Sci U S A 2023; 120:e2219179120. [PMID: 37364117 PMCID: PMC10318985 DOI: 10.1073/pnas.2219179120] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Accepted: 04/18/2023] [Indexed: 06/28/2023] Open
Abstract
The global ecological crisis of perfluoroalkyl and polyfluoroalkyl substances (PFASs) in drinking water has gradually shifted from long-chain to short-chain PFASs; however, the widespread established PFAS adsorption technology cannot cope with the impact of such hydrophilic pollutants given the inherent defects of solid-liquid mass transfer. Herein, we describe a reagent-free and low-cost strategy to reduce the energy state of short-chain PFASs in hydrophobic nanopores by employing an in situ constructed confined water structure in activated carbon (AC). Through direct (driving force) and indirect (assisted slip) effects, the confined water introduced a dual-drive mode in the confined water-encapsulated activated carbon (CW-AC) and completely eliminated the mass transfer barrier (3.27 to 5.66 kcal/mol), which caused the CW-AC to exhibit the highest adsorption capacity for various short-chain PFASs (C-F number: 3-6) among parent AC and other adsorbents reported. Meanwhile, benefiting from the chain length- and functional group-dependent confined water-binding pattern, the affinity of the CW-AC surpassed the traditional hydrophobicity dominance and shifted toward hydrophilic short-chain PFASs that easily escaped treatment. Importantly, the ability of CW-AC functionality to directly transfer to existing adsorption devices was verified, which could treat 21,000 bed volumes of environment-related high-load (~350 ng/L short-chain PFAS each) real drinking water to below the World Health Organization's standard. Overall, our results provide a green and cost-effective in situ upgrade scheme for existing adsorption devices to address the short-chain PFAS crisis.
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Affiliation(s)
- Yuanji Shi
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing210023, Jiangsu, PR China
| | - Hongxin Mu
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing210023, Jiangsu, PR China
| | - Jiaqian You
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing210023, Jiangsu, PR China
| | - Chenglong Han
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing210023, Jiangsu, PR China
| | - Huazai Cheng
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing210023, Jiangsu, PR China
| | - Jinfeng Wang
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing210023, Jiangsu, PR China
| | - Haidong Hu
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing210023, Jiangsu, PR China
| | - Hongqiang Ren
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing210023, Jiangsu, PR China
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35
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Mohona TM, Ye Z, Dai N, Nalam PC. Adsorption behavior of long-chain perfluoroalkyl substances on hydrophobic surface: A combined molecular characterization and simulation study. WATER RESEARCH 2023; 239:120074. [PMID: 37207455 DOI: 10.1016/j.watres.2023.120074] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Revised: 05/06/2023] [Accepted: 05/11/2023] [Indexed: 05/21/2023]
Abstract
Hydrophobic interaction is a prevalent sorption mechanism of poly- and perfluoroalkyl substances (PFAS) in natural and engineered environments. In this study, we combined quartz crystal microbalance with dissipation (QCM-D), atomic force microscope (AFM) with force mapping, and molecular dynamics (MD) simulation to probe the molecular behavior of PFAS at the hydrophobic interface. On a CH3-terminated self-assembled monolayer (SAM), perfluorononanoic acid (PFNA) showed ∼2-fold higher adsorption than perfluorooctane sulfonate (PFOS) that has the same fluorocarbon tail length but a different head group. Kinetic modeling using the linearized Avrami model suggests that the PFNA/PFOS-surface interaction mechanisms can evolve over time. This is confirmed by AFM force-distance measurements, which shows that while the adsorbed PFNA/PFOS molecules mostly lay flat, a portion of them formed aggregates/hierarchical structures of 1-10 nm in size after lateral diffusion on surface. PFOS showed a higher affinity to aggregate than PFNA. Association with air nanobubbles is observed for PFOS but not PFNA. MD simulations further showed that PFNA has a greater tendency than PFOS to have its tail inserted into the hydrophobic SAM, which can enhance adsorption but limit lateral diffusion, consistent with the relative behavior of PFNA/PFOS in QCM and AFM experiments. This integrative QCM-AFM-MD study reveals that the interfacial behavior of PFAS molecules can be heterogeneous even on a relatively homogeneous surface.
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Affiliation(s)
- Tashfia M Mohona
- Department of Civil, Structural and Environmental Engineering, University at Buffalo, Buffalo, NY, USA; Department of Materials Design and Innovation, University at Buffalo, Buffalo, NY, USA
| | - Zhijiang Ye
- Department of Mechanical and Manufacturing Engineering, Miami University, Oxford, OH, USA
| | - Ning Dai
- Department of Civil, Structural and Environmental Engineering, University at Buffalo, Buffalo, NY, USA.
| | - Prathima C Nalam
- Department of Materials Design and Innovation, University at Buffalo, Buffalo, NY, USA.
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36
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Lemay AC, Sontarp EJ, Martinez D, Maruri P, Mohammed R, Neapole R, Wiese M, Willemsen JAR, Bourg IC. Molecular Dynamics Simulation Prediction of the Partitioning Constants ( KH, Kiw, Kia) of 82 Legacy and Emerging Organic Contaminants at the Water-Air Interface. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:6296-6308. [PMID: 37014786 DOI: 10.1021/acs.est.3c00267] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
The tendency of organic contaminants (OCs) to partition between different phases is a key set of properties that underlie their human and ecological health impacts and the success of remediation efforts. A significant challenge associated with these efforts is the need for accurate partitioning data for an ever-expanding list of OCs and breakdown products. All-atom molecular dynamics (MD) simulations have the potential to help generate these data, but existing studies have applied these techniques only to a limited variety of OCs. Here, we use established MD simulation approaches to examine the partitioning of 82 OCs, including many compounds of critical concern, at the water-air interface. Our predictions of the Henry's law constant (KH) and interfacial adsorption coefficients (Kiw, Kia) correlate strongly with experimental results, indicating that MD simulations can be used to predict KH, Kiw, and Kia values with mean absolute deviations of 1.1, 0.3, and 0.3 logarithmic units after correcting for systematic bias, respectively. A library of MD simulation input files for the examined OCs is provided to facilitate future investigations of the partitioning of these compounds in the presence of other phases.
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Affiliation(s)
- Amélie C Lemay
- Department of Civil and Environmental Engineering, Princeton University, Princeton, New Jersey 08544, United States
| | - Ethan J Sontarp
- Department of Geosciences, Princeton University, Princeton, New Jersey 08544, United States
| | - Daniela Martinez
- Department of Civil and Environmental Engineering, Princeton University, Princeton, New Jersey 08544, United States
| | - Philip Maruri
- Department of Civil and Environmental Engineering, Princeton University, Princeton, New Jersey 08544, United States
| | - Raneem Mohammed
- Department of Civil and Environmental Engineering, Princeton University, Princeton, New Jersey 08544, United States
| | - Ryan Neapole
- Department of Civil and Environmental Engineering, Princeton University, Princeton, New Jersey 08544, United States
| | - Morgan Wiese
- Department of Civil and Environmental Engineering, Princeton University, Princeton, New Jersey 08544, United States
| | - Jennifer A R Willemsen
- Department of Civil and Environmental Engineering, Princeton University, Princeton, New Jersey 08544, United States
| | - Ian C Bourg
- Department of Civil and Environmental Engineering, Princeton University, Princeton, New Jersey 08544, United States
- High Meadows Environmental Institute, Princeton University, Princeton, New Jersey 08544, United States
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37
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Adu O, Ma X, Sharma VK. Bioavailability, phytotoxicity and plant uptake of per-and polyfluoroalkyl substances (PFAS): A review. JOURNAL OF HAZARDOUS MATERIALS 2023; 447:130805. [PMID: 36669401 DOI: 10.1016/j.jhazmat.2023.130805] [Citation(s) in RCA: 62] [Impact Index Per Article: 31.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2022] [Revised: 01/12/2023] [Accepted: 01/14/2023] [Indexed: 06/17/2023]
Abstract
Per- and polyfluoroalkyl substances (PFAS) are a group of legacy and emerging contaminants containing at least one aliphatic perfluorocarbon moiety. They display rapid and extensive transport in the environment due to their generally high water-solubility and weak adsorption onto soil particles. Because of their widespread presence in the environment and known toxicity, PFAS has become a serious threat to the ecosystem and public health. Plants are an essential component of the ecosystem and their uptake and accumulation of PFAS affect the fate and transport of PFAS in the ecosystem and has strong implications for human health. It is therefore imperative to investigate the interactions of plants with PFAS. This review presents a detailed discussion on the mechanisms of the bioavailability and plant uptake of PFAS, and essential factors affecting these processes. The phytotoxic effects of PFAS at physiological, biochemical, and molecular level were also carefully reviewed. At the end, key research gaps were identified, and future research needs were proposed.
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Affiliation(s)
- Olatunbosun Adu
- Department of Water Management and Hydrological Science, Texas A&M University, College Station, TX 77843, USA; Program for the Environment and Sustainability, Department of Environmental and Occupational Health, School of Public Health, Texas A&M University, 212 Adriance Lab Rd., 1266 TAMU, College Station, TX 77843, USA
| | - Xingmao Ma
- Department of Civil and Environmental Engineering, Texas A&M University, College Station, TX 77843, USA.
| | - Virender K Sharma
- Program for the Environment and Sustainability, Department of Environmental and Occupational Health, School of Public Health, Texas A&M University, 212 Adriance Lab Rd., 1266 TAMU, College Station, TX 77843, USA.
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38
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Melin TRL, Harell P, Ali B, Loganathan N, Wilson AK. Thermochemistry of per- and polyfluoroalkyl substances. J Comput Chem 2023; 44:570-580. [PMID: 36334029 PMCID: PMC10098614 DOI: 10.1002/jcc.27023] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Revised: 09/08/2022] [Accepted: 09/30/2022] [Indexed: 11/06/2022]
Abstract
The determination of gas phase thermochemical properties of per- and polyfluoroalkyl substances (PFAS) is central to understanding the long-range transport behavior of PFAS in the atmosphere. Prior gas-phase studies have reported the properties of perfluorinated sulfonic acid (PFOS) and perfluorinated octanoic acid (PFOA). Here, this study reports the gas phase enthalpies of formation of short- and long-chain PFAS and their precursor molecules determined using density functional theory (DFT) and ab initio approaches. Two density functionals, two ab initio methods and an empirical method were used to compute enthalpies of formation with the total atomization approach and an isogyric reaction. The performance of the computational methods employed in this work were validated against the experimental enthalpies of linear alkanoic acids and perfluoroalkanes. The gas-phase determinations will be useful for future studies of PFAS in the atmosphere, and the methodological choices will be helpful in the study of other PFAS.
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Affiliation(s)
- Timothé R L Melin
- Department of Chemistry, Michigan State University, East Lansing, Michigan, USA
| | - Preston Harell
- Department of Chemistry, Michigan State University, East Lansing, Michigan, USA
| | - Betoul Ali
- Department of Chemistry, Michigan State University, East Lansing, Michigan, USA
| | | | - Angela K Wilson
- Department of Chemistry, Michigan State University, East Lansing, Michigan, USA
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39
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Balgooyen S, Remucal CK. Impacts of Environmental and Engineered Processes on the PFAS Fingerprint of Fluorotelomer-Based AFFF. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:244-254. [PMID: 36573898 DOI: 10.1021/acs.est.2c06600] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Forensic analysis can potentially be used to determine per- and polyfluoroalkyl substance (PFAS) sources at contaminated sites. However, fluorotelomer aqueous film-forming foam (AFFF) sources are difficult to identify because the polyfluorinated active ingredients do not have authentic standards and because the parent compounds can undergo transformation and differential transport, resulting in alteration of the PFAS distribution or fingerprint. In this study, we investigate changes in the PFAS fingerprint of fluorotelomer-derived AFFF due to environmental and engineered processes, including groundwater transport, surface water flow, and land application of contaminated biosolids. Fingerprint analysis supplemented by quantification of precursors and identification of suspected active ingredients shows a clear correlation between a fluorotelomer AFFF manufacturer and surface water of nearby Lake Michigan, demonstrating contamination (>100 ng/L PFOA) of the lake due to migration of an AFFF-impacted groundwater plume. In contrast, extensive processing during wastewater treatment and environmental transport results in large changes to the AFFF fingerprint near agricultural fields where contaminated biosolids were spread. At biosolids-impacted sites, the presence of active ingredients confirms contamination by fluorotelomer AFFF. While sediments can retain longer-chain PFAS, this study demonstrates that aqueous samples are most relevant for PFAS fingerprinting in complex sites, particularly where shorter-chain compounds have been used.
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Affiliation(s)
- Sarah Balgooyen
- Department of Civil and Environmental Engineering, University of Wisconsin - Madison, 660 N. Park Street, Madison, Wisconsin 53706, United States
| | - Christina K Remucal
- Department of Civil and Environmental Engineering, University of Wisconsin - Madison, 660 N. Park Street, Madison, Wisconsin 53706, United States
- Environmental Chemistry and Technology Program, University of Wisconsin - Madison, 660 N. Park Street, Madison, Wisconsin 53706, United States
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40
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Jenness GR, Koval AM, Etz BD, Shukla MK. Atomistic insights into the hydrodefluorination of PFAS using silylium catalysts. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2022; 24:2085-2099. [PMID: 36165287 DOI: 10.1039/d2em00291d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Fluorochemicals are a persistent environmental contaminant that require specialized techniques for degradation and capture. In particular, recent attention on per- and poly-fluoroalkyl substances (PFAS) has led to numerous explorations of different techniques for degrading the super-strong C-F bonds found in these fluorochemicals. In this study, we investigated the hydrodefluorination mechanism using silylium-carborane salts for the degradation of PFAS at the density functional theory (DFT) level. We find that the degradation process involves both a cationic silylium (Et3Si+) and a hydridic silylium (Et3SiH) to facilitate the defluorination and hydride-addition events. Additionally, the role of carborane ([HCB11H5F6]-) is to force unoccupied anti-bonding orbitals to be partially occupied, weakening the C-F bond. We also show that changing the substituents on carborane from fluorine to other halogens weakens the C-F bond even further, with iodic carborane ([HCB11H5I6]-) having the greatest weakening effect. Moreover, our calculations reveal why the C-F bonds are resistant to degradation, and how the silylium-carborane chemistry is able to chemically transform these bonds into C-H bonds. We believe that our results are further applicable to other halocarbons, and can be used to treat either our existing stocks of these chemicals or to treat concentrated solutions following filtration and capture.
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Affiliation(s)
- Glen R Jenness
- Environmental Laboratory, US Army Engineer Research and Development Center, 3909 Halls Ferry Road, Vicksburg 39180, Mississippi, USA.
| | - Ashlyn M Koval
- Oak Ridge Institute for Science and Education (ORISE), 1299 Bethel Valley Rd, Oak Ridge 37830, Tennessee, USA
| | - Brian D Etz
- Oak Ridge Institute for Science and Education (ORISE), 1299 Bethel Valley Rd, Oak Ridge 37830, Tennessee, USA
| | - Manoj K Shukla
- Environmental Laboratory, US Army Engineer Research and Development Center, 3909 Halls Ferry Road, Vicksburg 39180, Mississippi, USA.
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41
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Choudhary A, Bedrov D. Interaction of Short-Chain PFAS with Polycationic Gels: How Much Fluorination is Necessary for Efficient Adsorption? ACS Macro Lett 2022; 11:1123-1128. [PMID: 36036717 DOI: 10.1021/acsmacrolett.2c00383] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The short-chain per- and polyfluorinated alkyl substances (PFAS), introduced to replace the legacy PFAS compounds, turned out to be as toxic and harmful as their longer-chain predecessors and even harder to sequester from contaminated water sources. In this work, molecular dynamics (MD) simulations are employed to investigate the adsorption mechanism of GenX, a representative compound for short-chain PFAS, on a polycationic hydrogel with various extents of fluorination in its backbone and cross-linkers. Simulations indicate that the presence of fluorinated segments next to cationic groups in the polymer gel structure provides the most efficient environment for GenX adsorption. The combination of electrostatic and hydrophobic interactions offered by the cationic-fluorophilic segments amplifies the binding of GenX molecules compared to polymer segments with nonfluorinated cationic or noncationic fluorinated segments. Moreover, such a gel demonstrates high selectivity toward GenX against its hydrogenated analogue.
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Affiliation(s)
- Aditya Choudhary
- Department Materials Science and Engineering, University of Utah, Salt Lake City, Utah 84112, United States
| | - Dmitry Bedrov
- Department Materials Science and Engineering, University of Utah, Salt Lake City, Utah 84112, United States
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