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Soltanian M, Gitipour S, Baghdadi M, Rtimi S. PFOA-contaminated soil remediation: a comprehensive review. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2024; 31:49985-50011. [PMID: 39088169 DOI: 10.1007/s11356-024-34516-y] [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: 01/17/2024] [Accepted: 07/23/2024] [Indexed: 08/02/2024]
Abstract
Soil and groundwater contamination has been raised as a concern due to the capability of posing a risk to human health and ecology, especially in facing highly toxic and emerging pollutants. Because of the prevalent usage of perfluorooctanoic acid (PFOA), in industrial and production processes, and subsequently the extent of sites contaminated with these pollutants, cleaning up PFOA polluted sites is paramount. This research provides a review of remediation approaches that have been used, and nine remediation techniques were reviewed under physical, chemical, and biological approaches categorization. As the pollutant specifications, environmental implications, and adverse ecological effects of remediation procedures should be considered in the analysis and evaluation of remediation approaches, unlike previous research that considered a couple of PFAS pollutants and generally dealt with technical issues, in this study, the benefits, drawbacks, and possible environmental and ecological adverse effects of PFOA-contaminated site remediation also were discussed. In the end, in addition to providing sufficient and applicable understanding by comprehensively considering all aspects and field-scale challenges and obstacles, knowledge gaps have been found and discussed.
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Affiliation(s)
- Mehdi Soltanian
- School of Civil and Environmental Engineering, Faculty of engineering and IT, University of Technology Sydney, Sydney, Australia
| | - Saeid Gitipour
- Faculty of Environment, College of Engineering, University of Tehran, Tehran, Iran
| | - Majid Baghdadi
- Faculty of Environment, College of Engineering, University of Tehran, Tehran, Iran
| | - Sami Rtimi
- Global Institute for Water Environment and Health, 1201, Geneva, Switzerland.
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2
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Ganbat N, Hamdi FM, Ibrar I, Altaee A, Alsaka L, Samal AK, Zhou J, Hawari AH. Iron slag permeable reactive barrier for PFOA removal by the electrokinetic process. JOURNAL OF HAZARDOUS MATERIALS 2023; 460:132360. [PMID: 37657326 DOI: 10.1016/j.jhazmat.2023.132360] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Revised: 08/14/2023] [Accepted: 08/20/2023] [Indexed: 09/03/2023]
Abstract
The efficacy of the Standalone Electrokinetic (EK) process in soil PFAS removal is negligible, primarily due to the intersecting mechanisms of electromigration and electroosmosis transportation. Consequently, the redistribution of PFAS across the soil matrix occurs, hampering effective remediation efforts. Permeable reactive barrier (PRB) has been used to capture contaminants and extract them at the end of the EK process. This study conducted laboratory-scale tests to evaluate the feasibility of the iron slag PRB enhanced-EK process in conjunction with Sodium Cholate (NaC) biosurfactant as a cost-effective and sustainable method for removing PFOA from the soil. A 2 cm iron slag-based PRB with a pH of 9.5, obtained from the steel-making industry, was strategically embedded in the middle of the EK reactors to capture PFOA within the soil. The main component of the slag, iron oxide, exhibited significant adsorption capacity for PFOA contamination. The laboratory-scale tests were conducted over two weeks, revealing a PFOA removal rate of more than 79% in the slag/activated carbon PRB-EK test with NaC enhancement and 70% PFOA removal in the slag/activated carbon PRB-EK without NaC. By extending the duration of the slag/AC PRB-EK test with NaC enhancement to three weeks, the PFOA removal rate increased to 94.09%, with the slag/AC PRB capturing over 87% of the initial PFOA concentration of 10 mg/L. The specific energy required for soil decontamination by the EK process was determined to be 0.15 kWh/kg. The outcomes of this study confirm the feasibility of utilizing iron slag waste in the EK process to capture PFOA contaminants, offering a sustainable approach to soil decontamination. Combining iron slag PRB and NaC biosurfactant provides a cost-effective and environmentally friendly method for efficient PFOA removal from soil.
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Affiliation(s)
- Namuun Ganbat
- Centre for Green Technology, School of Civil and Environmental Engineering, University of Technology Sydney, Australia
| | - Faris M Hamdi
- Centre for Green Technology, School of Civil and Environmental Engineering, University of Technology Sydney, Australia
| | - Ibrar Ibrar
- Centre for Green Technology, School of Civil and Environmental Engineering, University of Technology Sydney, Australia
| | - Ali Altaee
- Centre for Green Technology, School of Civil and Environmental Engineering, University of Technology Sydney, Australia.
| | - Lilyan Alsaka
- Centre for Green Technology, School of Civil and Environmental Engineering, University of Technology Sydney, Australia
| | - Akshaya K Samal
- Centre for Nano and Material Sciences, Jain University, Ramanagara, Bangalore 562 112, Karnataka, India
| | - John Zhou
- Centre for Green Technology, School of Civil and Environmental Engineering, University of Technology Sydney, Australia
| | - Alaa H Hawari
- Department of Civil and Architectural Engineering, College of Engineering, Qatar University, PO Box 2713, Doha, Qatar
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Bierbaum T, Klaas N, Braun J, Nürenberg G, Lange FT, Haslauer C. Immobilization of per- and polyfluoroalkyl substances (PFAS): Comparison of leaching behavior by three different leaching tests. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 876:162588. [PMID: 36871732 DOI: 10.1016/j.scitotenv.2023.162588] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 02/26/2023] [Accepted: 02/27/2023] [Indexed: 06/18/2023]
Abstract
The evaluation of PFAS immobilization performance in laboratory experiments, especially the long-term stability, is a challenge. To contribute to the development of adequate experimental procedures, the impact of experimental conditions on the leaching behavior was studied. Three experiments on different scales were compared: batch, saturated column, and variably saturated laboratory lysimeter experiments. The Infinite Sink (IS) test - a batch test with repeated sampling - was applied for PFAS for the first time. Soil from an agricultural field amended with paper-fiber biosolids polluted with various perfluoroalkyl acids (PFAAs; 655 μg/kg ∑18PFAAs) and polyfluorinated precursors (1.4 mg/kg ∑18precursors) was used as the primary material (N-1). Two types of PFAS immobilization agents were tested: treatment with activated carbon-based additives (soil mixtures: R-1 and R-2), and solidification with cement and bentonite (R-3). In all experiments, a chain-length dependent immobilization efficacy is observed. In R-3, the leaching of short-chain PFAAs was enhanced relative to N-1. In column and lysimeter experiments with R-1 and R-2, delayed breakthrough of short-chain PFAAs (C4) occurred (> 90 days; in column experiments at liquid-to-solid ratio (LS) > 30 L/kg) with similar temporal leaching rates suggesting that leaching in these cases was a kinetically controlled process. Observed differences between column and lysimeter experiments may be attributed to varying saturation conditions. In IS experiments, PFAS desorption from N-1, R-1, and R-2 is higher than in the column experiments (N-1: +44 %; R-1: +280 %; R-2: +162 %), desorption of short-chain PFAS occurred predominantly in the initial phase (< 14 days). Our findings demonstrate that sufficient operating times are essential in percolation experiments, e.g., in column experiments >100 days and LS > 30 L/kg. IS experiments may provide a faster estimate for nonpermanent immobilization. The comparison of experimental data from various experiments is beneficial to evaluate PFAS immobilization and to interpret leaching characteristics.
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Affiliation(s)
- Thomas Bierbaum
- University of Stuttgart, Institute for Modelling Hydraulic and Environmental Systems (IWS), Research Facility for Subsurface Remediation (VEGAS), Pfaffenwaldring 61, 70597 Stuttgart, Germany.
| | - Norbert Klaas
- University of Stuttgart, Institute for Modelling Hydraulic and Environmental Systems (IWS), Research Facility for Subsurface Remediation (VEGAS), Pfaffenwaldring 61, 70597 Stuttgart, Germany
| | - Jürgen Braun
- University of Stuttgart, Institute for Modelling Hydraulic and Environmental Systems (IWS), Research Facility for Subsurface Remediation (VEGAS), Pfaffenwaldring 61, 70597 Stuttgart, Germany
| | - Gudrun Nürenberg
- TZW: DVGW-Technologiezentrum Wasser (German Water Centre), Karlsruher Straße 84, 76139 Karlsruhe, Germany
| | - Frank Thomas Lange
- TZW: DVGW-Technologiezentrum Wasser (German Water Centre), Karlsruher Straße 84, 76139 Karlsruhe, Germany
| | - Claus Haslauer
- University of Stuttgart, Institute for Modelling Hydraulic and Environmental Systems (IWS), Research Facility for Subsurface Remediation (VEGAS), Pfaffenwaldring 61, 70597 Stuttgart, Germany
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Navarro DA, Kabiri S, Ho J, Bowles KC, Davis G, McLaughlin MJ, Kookana RS. Stabilisation of PFAS in soils: Long-term effectiveness of carbon-based soil amendments. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2023; 323:121249. [PMID: 36764376 DOI: 10.1016/j.envpol.2023.121249] [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: 12/19/2022] [Revised: 01/27/2023] [Accepted: 02/07/2023] [Indexed: 06/18/2023]
Abstract
Immobilisation/stabilisation is one of the most developed and studied approaches for treating soils contaminated with per- and poly-fluoroalkyl substances (PFAS). However, its application has been inhibited by insufficient understanding of the effectiveness of added soil sorbents over time. Herein, we present results on the effectiveness of select carbon-based sorbents, over 4 years (longevity) and multiple laboratory leaching conditions (durability). Standard batch leaching tests simulating aggressive, worst-case scenario conditions for leaching (i.e., shaking for 24-48 h at high liquid/solid ratios) were employed to test longevity and durability of stabilisation in clay-loam and sandy-loam soils historically contaminated with PFAS (2 and 14 mg/kg ∑28 PFAS). The different sorbents, which were applied at 1-6% (w/w), reduced leaching of PFAS from the soils to varying degrees. Among the 5 sorbents tested, initial assessments completed 1 week after treatment revealed that 2 powdered activated carbon (PAC) sorbents and 1 biochar were able to reduce leaching of PFAS in the soil by at least 95%. Four years after treatment, the performance of the PAC sorbents did not significantly change, whilst colloidal AC improved and was able to reduce leaching of PFAS by at least 94%. The AC-treated soils also appeared to be durable and achieved at least 95% reduction in PFAS leaching under repetitive leaching events (5 times extraction) and with minimal effect of pH (pH 4-10.5). In contrast, the biochars were affected by aging and were at least 22% less effective in reducing PFAS leaching across a range of leaching conditions. Sorbent performance was generally consistent with the sorbent's physical and chemical characteristics. Overall, the AC sorbents used in this study appeared to be better than the biochars in stabilising PFAS in the long term.
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Affiliation(s)
- Divina A Navarro
- CSIRO Environment, PMB 2, Glen Osmond, SA, 5064, Australia; School of Agriculture, Food and Wine, The University of Adelaide, Waite Campus, PMB1, Glen Osmond, South Australia, 5064, Australia.
| | - Shervin Kabiri
- School of Agriculture, Food and Wine, The University of Adelaide, Waite Campus, PMB1, Glen Osmond, South Australia, 5064, Australia
| | - Jonathan Ho
- AECOM Australia Pty Ltd, Sydney, NSW, 2000, Australia
| | - Karl C Bowles
- RPS AAP Consulting Pty Ltd, 420 George Street, Sydney, NSW, 2000, Australia; Queensland Alliance for Environmental Health Sciences, The University of Queensland, level 4/20 Cornwall St, Woolloongabba, QLD, 4102, Australia
| | - Greg Davis
- CSIRO Environment, 147 Underwood Avenue, Floreat, Western Australia, 6014, Australia
| | - Mike J McLaughlin
- School of Agriculture, Food and Wine, The University of Adelaide, Waite Campus, PMB1, Glen Osmond, South Australia, 5064, Australia
| | - Rai S Kookana
- CSIRO Environment, PMB 2, Glen Osmond, SA, 5064, Australia; School of Agriculture, Food and Wine, The University of Adelaide, Waite Campus, PMB1, Glen Osmond, South Australia, 5064, Australia
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5
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Sleep JA, Miklavcic SJ, Juhasz AL. Modelling of PFAS-surface interactions: Effect of surface charge and solution ions. CHEMOSPHERE 2023; 319:137910. [PMID: 36706812 DOI: 10.1016/j.chemosphere.2023.137910] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Revised: 12/01/2022] [Accepted: 01/17/2023] [Indexed: 06/18/2023]
Abstract
PER-: and poly-fluoroalkyl substances (PFAS) are a class of substances of increasing concern as environmental contaminants. The interactions between PFAS and surfaces play an important role in PFAS transport and remediation. Previous studies have found PFAS adsorption to be dependent upon properties including pH, organic matter and particle size, along with PFAS functional group and carbon chain length. It is hypothesised that a theoretical examination of PFAS-surface interactions, via Monte Carlo molecular simulation, would show differences resulting from changes in surface charge, H+, OH-, Ca2+ concentrations and PFAS carbon chain length. Monte Carlo molecular simulations of perfluorooctane and perfluorobutane sulfonic acids interacting with a graphite surface in an aqueous medium were performed. Variations in surface charge, H+, OH- and Ca2+ concentrations were made. The distance-dependent density of molecules from the surface was analysed as a proxy for PFAS adsorption to the surface. Simulation results showed differences in surface behaviour that depended on surface charge, H+, OH- and Ca2+ concentrations, along with carbon chain length, with surface charge playing the most prominent role in controlling PFAS adsorption. For negatively charged surfaces, adsorption due to divalent cation bridging was observed in Ca2+ solutions. Modelling, such as in this study, of the thermodynamic equilibrium behaviour of low concentrations of molecules, in scenarios where both adsorption and mobility of PFAS occur, can aid in the design and testing of sorptive surfaces for amendment-based PFAS remediation.
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Affiliation(s)
- Julie A Sleep
- Future Industries Institute, University of South Australia, Mawson Lakes, SA, 5095, Australia.
| | - Stanley J Miklavcic
- Phenomics and Bioinformatics Research Centre, University of South Australia, Mawson Lakes, SA, 5095, Australia.
| | - Albert L Juhasz
- Future Industries Institute, University of South Australia, Mawson Lakes, SA, 5095, Australia.
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6
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Basic principles and problems in decontamination of natural disperse systems. The electrokinetic treatment of soils. Adv Colloid Interface Sci 2022; 310:102798. [DOI: 10.1016/j.cis.2022.102798] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Revised: 10/15/2022] [Accepted: 10/15/2022] [Indexed: 11/20/2022]
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Lindh P, Lemenkova P. Dynamics of Strength Gain in Sandy Soil Stabilised with Mixed Binders Evaluated by Elastic P-Waves during Compressive Loading. MATERIALS (BASEL, SWITZERLAND) 2022; 15:7798. [PMID: 36363389 PMCID: PMC9657054 DOI: 10.3390/ma15217798] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Revised: 10/30/2022] [Accepted: 11/01/2022] [Indexed: 06/16/2023]
Abstract
This paper addresses the problem of stabilisation of poor subgrade soil for improving its engineering properties and stiffness. The study aim is to evaluate the effects from single and mixed binders on the gain of strength in sandy soil over the period of curing. We propose an effective non-destructive approach of using P-waves for identifying soil strength upon stabilisation. The growth of strength and stiffness is strongly dependent on time of curing and type of the stabilising agents which can include both single binders and their blended mixtures. The diverse effects from mixed binders on the properties of soil were evaluated, compared and analysed. We performed the experimental trials of five different binders for stabilisation of sandy soil using cement, lime, Ground Granulated Blast Furnace Slag (GGBFS), energy fly ash and bio fly ash. The methodology included soil stabilisation by binders during a total period of 90 days, strength test for the Unconfined Compressive Strength (UCS) and seismic tests on the stabilised samples. The dynamics of soil behaviour stabilised by different binders for days 7, 14, 28 and 90 was statistically analysed and compared. The optimisation of binder blending has been performed using mixture simplex lattice design with three binders in each case as independent variables. Using P-waves naturally exploited strength characteristics of soil samples and allowed us to compare the effects from the individual and blended binders over the complete period of curing with dominating mixes. The results indicate that strength growth in stabilised soil samples is nonlinear in both time and content of binders with dominating effects from slag which contributed the most to the compressive strength development, followed by cement.
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Affiliation(s)
- Per Lindh
- Swedish Transport Administration, Neptunigatan 52, P.O. Box 366, SE-201-23 Malmö, Sweden
- Division of Building Materials, Department of Building and Environmental Technology, Lunds Tekniska Högskola (LTH), Faculty of Engineering, Lund University, P.O. Box 118, SE-221-00 Lund, Sweden
| | - Polina Lemenkova
- Laboratory of Image Synthesis and Analysis, Building L, École Polytechnique de Bruxelles, Brussels Faculty of Engineering, Campus de Solbosch, Université Libre de Bruxelles, ULB–LISA CP165/57, Avenue Franklin D. Roosevelt 50, B-1050 Brussels, Belgium
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8
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Niarchos G, Ahrens L, Kleja DB, Fagerlund F. Per- and polyfluoroalkyl substance (PFAS) retention by colloidal activated carbon (CAC) using dynamic column experiments. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2022; 308:119667. [PMID: 35750303 DOI: 10.1016/j.envpol.2022.119667] [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: 03/22/2022] [Revised: 06/16/2022] [Accepted: 06/18/2022] [Indexed: 06/15/2023]
Abstract
Developing effective remediation methods for per- and polyfluoroalkyl substance (PFAS)-contaminated soils is a substantial step towards counteracting their widespread occurrence and protecting our ecosystems and drinking water sources. Stabilisation of PFAS in the subsurface using colloidal activated carbon (CAC) is an innovative, yet promising technique, requiring better understanding. In this study, dynamic soil column tests were used to assess the retardation of 10 classical perfluoroalkyl acids (PFAAs) (C5-C11 perfluoroalkyl carboxylic acids (PFCAs) and C4, C6, C8 perfluoroalkane sulfonates (PFSAs)) as well as two alternative PFAS (6:2 and 8:2 fluorotelomer sulfonates) using CAC at 0.03% w/w, to investigate the fate and transport of PFAS under CAC treatment applications. Results showed high retardation rates for long-chain PFAS and eight times higher retardation for the CAC-treated soil compared to the non-treated reference soil for the ∑PFAS. Replacement of shorter chain perfluorocarboxylic acids (PFCAs), such as perfluoropentanoic acid (PFPeA), by longer chained PFAS was observed, indicating competition effects. Partitioning coefficients (Kd values) were calculated for the CAC fraction at ∼103-105 L kg-1 for individual PFAS, while there was a significant positive correlation (p < 0.05) between perfluorocarbon chain length and Kd. Mass balance calculations showed 37% retention of ∑PFAS in treated soil columns after completion of the experiments and 99.7% higher retention rates than the reference soil. Redistribution and elution of CAC were noticed and quantified through organic carbon analysis, which showed a 23% loss of carbon during the experiments. These findings are a step towards better understanding the extent of CAC's potential for remediation of PFAS-contaminated soil and groundwater and the limitations of its applications.
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Affiliation(s)
- Georgios Niarchos
- Department of Earth Sciences, Uppsala University, P.O. Box 256, SE-751 05, Uppsala, Sweden.
| | - Lutz Ahrens
- Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences (SLU), P.O. Box 7050, SE-750 07, Uppsala, Sweden
| | - Dan Berggren Kleja
- Department of Soil and Environment, Swedish University of Agricultural Sciences (SLU), P. O. Box 7090, SE-750 07, Uppsala, Sweden
| | - Fritjof Fagerlund
- Department of Earth Sciences, Uppsala University, P.O. Box 256, SE-751 05, Uppsala, Sweden
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Dickman RA, Aga DS. A review of recent studies on toxicity, sequestration, and degradation of per- and polyfluoroalkyl substances (PFAS). JOURNAL OF HAZARDOUS MATERIALS 2022; 436:129120. [PMID: 35643010 DOI: 10.1016/j.jhazmat.2022.129120] [Citation(s) in RCA: 61] [Impact Index Per Article: 30.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Revised: 05/04/2022] [Accepted: 05/07/2022] [Indexed: 05/27/2023]
Abstract
The fate, effects, and treatment of per- and polyfluoroalkyl substances (PFAS), an anthropogenic class of chemicals used in industrial and commercial production, are topics of great interest in recent research and news cycles. This interest stems from the ubiquity of PFAS in the global environment as well as their significant toxicological effects in humans and wildlife. Research on toxicity, sequestration, removal, and degradation of PFAS has grown rapidly, leading to a flood of valuable knowledge that can get swamped out in the perpetual rise in the number of publications. Selected papers from the Journal of Hazardous Materials between January 2018 and May 2022 on the toxicity, sequestration, and degradation of PFAS are reviewed in this article and made available as open-access publications for one year, in order to facilitate the distribution of critical knowledge surrounding PFAS. This review discusses routes of toxicity as observed in mammalian and cellular models, and the observed human health effects in exposed communities. Studies that evaluate of toxicity through in-silico approaches are highlighted in this paper. Removal of PFAS through modified carbon sorbents, nanoparticles, and anion exchange materials are discussed while comparing treatment efficiencies for different classes of PFAS. Finally, various biotic and abiotic degradation techniques, and the pathways and mechanisms involved are reviewed to provide a better understanding on the removal efficiencies and cost effectiveness of existing treatment strategies.
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Affiliation(s)
- Rebecca A Dickman
- Department of Chemistry, The State University of New York at Buffalo, Buffalo, NY 14260, United States
| | - Diana S Aga
- Department of Chemistry, The State University of New York at Buffalo, Buffalo, NY 14260, United States.
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Ambaye TG, Vaccari M, Prasad S, Rtimi S. Recent progress and challenges on the removal of per- and poly-fluoroalkyl substances (PFAS) from contaminated soil and water. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:58405-58428. [PMID: 35754080 DOI: 10.1007/s11356-022-21513-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Accepted: 06/12/2022] [Indexed: 06/15/2023]
Abstract
Currently, due to an increase in urbanization and industrialization around the world, a large volume of per- and poly-fluoroalkyl substances (PFAS) containing materials such as aqueous film-forming foam (AFFF), protective coatings, landfill leachates, and wastewater are produced. Most of the polluted wastewaters are left untreated and discharged into the environment, which causes high environmental risks, a threat to human beings, and hampered socioeconomic growth. Developing sustainable alternatives for removing PFAS from contaminated soil and water has attracted more attention from policymakers and scientists worldwide under various conditions. This paper reviews the recent emerging technologies for the degradation or sorption of PFAS to treat contaminated soil and water. It highlights the mechanisms involved in removing these persistent contaminants at a molecular level. Recent advances in developing nanostructured and advanced reduction remediation materials, challenges, and perspectives in the future are also discussed. Among the variety of nanomaterials, modified nano-sized iron oxides are the best sorbents materials due to their specific surface area and photogenerated holes and appear extremely promising in the remediation of PFAS from contaminated soil and water.
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Affiliation(s)
- Teklit Gebregiorgis Ambaye
- Department of Civil, Environmental, Architectural Engineering and Mathematics, University of Brescia, Via Branze 43, 25123, Brescia, Italy
| | - Mentore Vaccari
- Department of Civil, Environmental, Architectural Engineering and Mathematics, University of Brescia, Via Branze 43, 25123, Brescia, Italy
| | - Shiv Prasad
- Division of Environment Science, ICAR-Indian Agricultural Research Institute New Delhi, New Delhi, 110012, India
| | - Sami Rtimi
- Global Institute for Water, Environment and Health, CH-1201, Geneva, Switzerland.
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11
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McDonough JT, Anderson RH, Lang JR, Liles D, Matteson K, Olechiw T. Field-Scale Demonstration of PFAS Leachability Following In Situ Soil Stabilization. ACS OMEGA 2022; 7:419-429. [PMID: 35036711 PMCID: PMC8756798 DOI: 10.1021/acsomega.1c04789] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Accepted: 12/09/2021] [Indexed: 05/06/2023]
Abstract
A field-scale validation is summarized comparing the efficacy of commercially available stabilization amendments with the objective of mitigating per- and polyfluoroalkyl substance (PFAS) leaching from aqueous film-forming foam (AFFF)-impacted source zones. The scope of this work included bench-scale testing to evaluate multiple amendments and application concentrations to mitigate PFAS leachability and the execution of field-scale soil mixing in an AFFF-impacted fire-training area with nearly 2.5 years of post-soil mixing monitoring to validate reductions in PFAS leachability. At the bench scale, several amendments were evaluated and the selection of two amendments for field-scale evaluation was informed: FLUORO-SORB Adsorbent (FS) and RemBind (RB). Five ∼28 m3 test pits (approximately 3 m wide by 3 m long by 3 m deep) were mixed at a site using conventional construction equipment. One control test pit (Test Pit 1) included Portland cement (PC) only (5% dry weight basis). The other four test pits (Test Pits 2 through 5) compared 5 and 10% ratios (dry weight basis) of FS and RB (also with PC). Five separate monitoring events included two to three sample cores collected from each test pit for United States Environmental Protection Agency (USEPA) Method 1315 leaching assessment. After 1 year, a mass balance for each test pit was attempted comparing the total PFAS soil mass before, during, and after leach testing. Bench-scale and field-scale data were in good agreement and demonstrated >99% decrease in total PFAS leachability (mass basis; >98% mole basis) as confirmed by the total oxidizable precursor assay, strongly supporting the chemical stabilization of PFAS.
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Affiliation(s)
- Jeffrey T. McDonough
- Arcadis, 630 Plaza Drive
Suite 200, Highlands Ranch, Colorado 80129, United
States
- . Phone: 267-615-1863
| | - Richard H. Anderson
- Air
Force Civil Engineer Center (AFCEC), San Antonio, Texas 78056, United States
| | - Johnsie R. Lang
- Arcadis, 630 Plaza Drive
Suite 200, Highlands Ranch, Colorado 80129, United
States
| | - David Liles
- Arcadis, 630 Plaza Drive
Suite 200, Highlands Ranch, Colorado 80129, United
States
| | - Kasey Matteson
- Arcadis, 630 Plaza Drive
Suite 200, Highlands Ranch, Colorado 80129, United
States
| | - Theresa Olechiw
- Arcadis, 630 Plaza Drive
Suite 200, Highlands Ranch, Colorado 80129, United
States
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12
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Uriakhil MA, Sidnell T, De Castro Fernández A, Lee J, Ross I, Bussemaker M. Per- and poly-fluoroalkyl substance remediation from soil and sorbents: A review of adsorption behaviour and ultrasonic treatment. CHEMOSPHERE 2021; 282:131025. [PMID: 34118624 DOI: 10.1016/j.chemosphere.2021.131025] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 05/25/2021] [Accepted: 05/25/2021] [Indexed: 06/12/2023]
Abstract
Per- and poly-fluoroalkyl substances (PFAS) are xenobiotics, present at variable concentrations in soils and groundwater worldwide. Some of the current remediation techniques being researched or applied for PFAS-impacted soils involve solidification-stabilisation, soil washing, excavation and disposal to landfill, on site or in situ smouldering, thermal desorption, ball milling and incineration. Given the large volumes of soil requiring treatment, there is a need for a more environmentally friendly technique to remove and treat PFASs from soils. Sorbents such as granular/powdered activated carbon, ion exchange resins and silicas are used in water treatment to remove PFAS. In this work, PFAS adsorption mechanisms and the effect of pore size, pH and organic matter on adsorption efficacy are discussed. Then, adsorption of PFAS to soils and sorbents is considered when assessing the viability of remediation techniques. Sonication-aided treatment was predicted to be an effective removal technique for PFAS from a solid phase, and the effect of varying frequency, power and particle size on the effectiveness of the desorption process is discussed. Causes and mitigation strategies for possible cavitation-induced particle erosion during ultrasound washing are also identified. Following soil remediation, degrading the extracted PFAS using sonolysis in a water-organic solvent mixture is discussed. The implications for future soil remediation and sorbent regeneration based on the findings in this study are given.
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Affiliation(s)
- Mohammad Angaar Uriakhil
- University of Surrey, Department of Chemical and Process Engineering, Surrey, England, GU2 7XH, UK
| | - Tim Sidnell
- University of Surrey, Department of Chemical and Process Engineering, Surrey, England, GU2 7XH, UK
| | | | - Judy Lee
- University of Surrey, Department of Chemical and Process Engineering, Surrey, England, GU2 7XH, UK
| | - Ian Ross
- Tetra Tech, Quay West at MediaCityUK, Trafford Wharf Rd, Trafford Park, Manchester, England, M17 1HH, UK
| | - Madeleine Bussemaker
- University of Surrey, Department of Chemical and Process Engineering, Surrey, England, GU2 7XH, UK.
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Barth E, McKernan J, Bless D, Dasu K. Investigation of an immobilization process for PFAS contaminated soils. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2021; 296:113069. [PMID: 34225046 PMCID: PMC8682492 DOI: 10.1016/j.jenvman.2021.113069] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Revised: 05/26/2021] [Accepted: 06/09/2021] [Indexed: 05/06/2023]
Abstract
A two-phased bench-scale study was conducted to evaluate various sorbents for possible use as chemical stabilizing agents, along with cement solidification, for possible use in an in-situ solidification/stabilization (immobilization) treatment process for per- and polyfluoroalkyl (PFAS) contaminated soils. The first phase involved sorption experiments for six selected PFAS compounds diluted in a water solution, using five selected sorbents: granular activated carbon (GAC), activated carbon-clay blend, modified clay, biochar, iron (Fe)-amended biochar, and Ottawa sand as a control media. The second phase involved chemical stabilization treatment (via sorption), using the most effective sorbent identified in the first phase, followed by solidification of two soils from PFAS-contaminated sites. Physical solidification was achieved by adding cement as a binding agent. Results from the first phase (sorption experiments) indicated that GAC was slightly more successful than the other sorbents in sorption performance for a 3000 μg/L solution containing a mixture of the six selected PFAS analytes (500 μg/L concentration each of shorter- and longer-chain alkyl acids), and was the only sorbent used in the second phase of this study. While the GAC, activated carbon-clay blend, and modified clay sorbents showed similar sorption performance for the longer chain analytes tested, both the activated carbon-clay blend and modified clay, exhibited slightly less sorptive capacity than GAC for the shorter-chain alkyl acids. Immobilization effectiveness was evaluated by soil leachability testing using Environmental Protection Agency (EPA) Method 1312, Synthetic Precipitation Leaching Procedure (SPLP) on the samples collected from two PFAS-contaminated sites. For the majority of the PFAS soil analytes, the addition of GAC sorbent (chemical stabilization) substantially reduced the leachability of PFAS compounds from the contaminated soil samples, and the addition of cement as a physical binding agent (solidification) further decreased leachability for a few of the PFAS compounds. Overall immobilization of PFAS analytes that were detectable in the leachate from two PFAS contaminated soils ranged from 87.1% to 99.9%. Therefore, it is reasonable to consider that the laboratory testing results presented here may have application to further pilot or limited field-scale studies within a broader suite of PFAS-contaminated site treatment options that are currently available for treating PFAS contaminated soils.
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Affiliation(s)
- Edwin Barth
- U.S. EPA. Office of Research and Development, Center for Environmental Solutions and Emergency Response, 26 MLK Dr, Cincinnati, OH, 45268, USA.
| | - John McKernan
- U.S. EPA. Office of Research and Development, Center for Environmental Solutions and Emergency Response, 26 MLK Dr, Cincinnati, OH, 45268, USA.
| | - Diana Bless
- U.S. EPA. Office of Research and Development, Center for Environmental Solutions and Emergency Response, 26 MLK Dr, Cincinnati, OH, 45268, USA.
| | - Kavitha Dasu
- Battelle Memorial Institute, 505 King Ave, Columbus, OH, 43201, USA.
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