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Stults JF, Schaefer CE, Fang Y, Devon J, Nguyen D, Real I, Hao S, Guelfo JL. Air-water interfacial collapse and rate-limited solid desorption control Perfluoroalkyl acid leaching from the vadose zone. JOURNAL OF CONTAMINANT HYDROLOGY 2024; 265:104382. [PMID: 38861839 DOI: 10.1016/j.jconhyd.2024.104382] [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: 01/31/2024] [Revised: 05/08/2024] [Accepted: 06/02/2024] [Indexed: 06/13/2024]
Abstract
Some Per- and polyfluoroalkyl substances (PFAS) are strongly retained in the vadose zone due to their sorption to both soils and air-water interfaces. While significant research has been dedicated to understanding equilibrium behavior for these multi-phase retention processes, leaching and desorption from aqueous film-forming foam (AFFF) impacted soils under field relevant conditions can exhibit significant deviations from equilibrium. Herein, laboratory column studies using field collected AFFF-impacted soils were employed to examine the leaching of perfluoroalkyl acids (PFAAs) under simulated rainfall conditions. The HYDRUS 1-D model was calibrated to estimate the unsaturated hydraulic properties of the soil in a layered system using multiple boundary condtions. Forward simulations of equilibrium PFAS partitioning using the HYDRUS model and simplified mass balance calculations showed good agreement with the net PFAS mass flux out of the column. However, neither were able to predict the PFAS concentrations in the leached porewater. To better understand the mechanisms controlling the leaching behavior, the HYDRUS 1-D two-site leaching model incorporating solid phase rate limitation and equilibrium air-water interfacial partitioning was employed. Three variations of the novel model incorporating different forms of equilibrium air-water interfacial partitioning were considered using built-in numerical inversion. Results of numerical inversion show that a combination of air-water interfacial collapse and rate-limited desorption from soils can better predict the unique leaching behavior exhibited by PFAAs in AFFF-impacted soils. A sensitivity analysis of the initial conditions and rate-limited desorption terms was conducted to assess the agreement of the model with measured data. The models demonstrated herein show that, under some circumstances, laboratory equilibrium partitioning data can provide a reasonable estimation of total mass leaching, but fail to account for the significant rate-limited, non-Fickian transport which affect PFAA leaching to groundwater in unsaturated soils.
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Affiliation(s)
- John F Stults
- CDM Smith, 14432 SE Eastgate Way, Suite 100, Bellevue, WA 98007, United States.
| | - Charles E Schaefer
- CDM Smith, 14432 SE Eastgate Way, Suite 100, Bellevue, WA 98007, United States; CDM Smith, 110 Fieldcrest Avenue, #8, 6th Floor, Edison, NJ 08837, United States
| | - Yida Fang
- CDM Smith, 14432 SE Eastgate Way, Suite 100, Bellevue, WA 98007, United States; Haley and Aldrich Inc., 3131 Elliott Ave #600, Seattle, WA 98121, United States
| | - Julie Devon
- CDM Smith, 14432 SE Eastgate Way, Suite 100, Bellevue, WA 98007, United States
| | - Dung Nguyen
- CDM Smith, 14432 SE Eastgate Way, Suite 100, Bellevue, WA 98007, United States
| | - Isreq Real
- Civil, Environmental, and Construction Engineering, Texas Tech University, Lubbock, TX 79409, USA
| | - Shilai Hao
- Civil & Environmental Engineering, Colorado School of Mines, Golden, CO 80401, USA
| | - Jennifer L Guelfo
- Civil, Environmental, and Construction Engineering, Texas Tech University, Lubbock, TX 79409, USA
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Yan PF, Dong S, Pennell KD, Cápiro NL. A review of the occurrence and microbial transformation of per- and polyfluoroalkyl substances (PFAS) in aqueous film-forming foam (AFFF)-impacted environments. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 927:171883. [PMID: 38531439 DOI: 10.1016/j.scitotenv.2024.171883] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2023] [Revised: 03/15/2024] [Accepted: 03/20/2024] [Indexed: 03/28/2024]
Abstract
Aqueous film-forming foams (AFFFs) have been extensively used for extinguishing hydrocarbon-fuel fires at military sites, airports, and fire-training areas. Despite being a significant source of per- and polyfluoroalkyl substances (PFAS), our understanding of PFAS occurrence in AFFF formulations and AFFF-impacted environments is limited, as is the impact of microbial transformation on the environment fate of AFFF-derived PFAS. This literature review compiles PFAS concentrations in electrochemical fluorination (ECF)- and fluorotelomer (FT)-based AFFFs and provides an overview of PFAS occurrence in AFFF-impacted environments. Our analysis reveals that AFFF use is a predominant point source of PFAS contamination, including primary precursors (polyfluoroalkyl substances as AFFF components), secondary precursors (polyfluoroalkyl transformation products of primary precursors), and perfluoroalkyl acids (PFAAs). Moreover, there are discrepancies between PFAS concentration profiles in AFFFs and those measured in AFFF-impacted media. For example, primary precursors constitute 52.6 % and 99.5 % of PFAS mass in ECF- and FT-based AFFFs, respectively, whereas they represent only 0.7 % total mass in AFFF-impacted groundwater. Conversely, secondary precursors, which constitute <1 % of PFAS in AFFFs, represent 4.0-27.8 % of PFAS in AFFF-impacted environments. The observed differences in PFAS levels between AFFFs and environmental samples are likely due to in-situ biotransformation processes. Biotransformation rates and pathways reported for AFFF-derived primary and secondary precursors varied among different classes of precursors, consistent with the PFAS occurrence in AFFF-impacted environments. For example, readily biodegradable primary precursors, N-dimethyl ammonio propyl perfluoroalkane sulfonamide (AmPr-FASA) and n:2 fluorotelomer thioether amido sulfonate (n:2 FtTAoS), were rarely detected in AFFF-impacted environments. In contrast, key secondary precursors, perfluoroalkane sulfonamides (FASAs) and n:2 fluorotelomer sulfonate (n:2 FTS), were widely detected, which was attributed to their resistance to biotransformation. Key knowledge gaps and future research priorities are presented to better understand the occurrence, fate, and transport of AFFF-derived PFAS in the environment and to design more effective remediation strategies.
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Affiliation(s)
- Peng-Fei Yan
- Department of Biological and Environmental Engineering, Cornell University, Ithaca, NY, United States of America.
| | - Sheng Dong
- Department of Biological and Environmental Engineering, Cornell University, Ithaca, NY, United States of America
| | - Kurt D Pennell
- School of Engineering, Brown University, Providence, RI, United States of America
| | - Natalie L Cápiro
- Department of Biological and Environmental Engineering, Cornell University, Ithaca, NY, United States of America.
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Saha B, Ateia M, Fernando S, Xu J, DeSutter T, Iskander SM. PFAS occurrence and distribution in yard waste compost indicate potential volatile loss, downward migration, and transformation. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2024; 26:657-666. [PMID: 38312055 DOI: 10.1039/d3em00538k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2024]
Abstract
We discovered high concentrations of PFAS (18.53 ± 1.5 μg kg-1) in yard waste compost, a compost type widely acceptable to the public. Seventeen out of forty targeted PFAS, belonging to six PFAS classes were detected in yard waste compost, with PFCAs (13.51 ± 0.99 μg kg-1) and PFSAs (4.13 ± 0.19 μg kg-1) being the dominant classes, comprising approximately 72.5% and 22.1% of the total measured PFAS. Both short-chain PFAS, such as PFBA, PFHxA, and PFBS, and long-chain PFAS, such as PFOA and PFOS, were prevalent in all the tested yard waste compost samples. We also discovered the co-occurrence of PFAS with low-density polyethylene (LDPE) and polyethylene terephthalate (PET) plastics. Total PFAS concentrations in LDPE and PET separated from incoming yard waste were 7.41 ± 0.41 μg kg-1 and 1.35 ± 0.1 μg kg-1, which increased to 8.66 ± 0.81 μg kg-1 in LDPE and 5.44 ± 0.56 μg kg-1 in PET separated from compost. An idle mature compost pile revealed a clear vertical distribution of PFAS, with the total PFAS concentrations at the surface level approximately 58.9-63.2% lower than the 2 ft level. This difference might be attributed to the volatile loss of short-chain PFCAs, PFAS's downward movement with moisture, and aerobic transformations of precursor PFAS at the surface.
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Affiliation(s)
- Biraj Saha
- Department of Civil, Construction and Environmental Engineering, North Dakota State University, 1410 14th Ave N, CIE 201, Fargo, North Dakota 58102, USA.
| | - Mohamed Ateia
- Department of Chemical and Biomolecular Engineering, Rice University, Houston, Texas 77005, USA
| | - Sujan Fernando
- Department of Civil and Environmental Engineering, Clarkson University, Potsdam, New York 13699, USA
| | - Jiale Xu
- Department of Civil, Construction and Environmental Engineering, North Dakota State University, 1410 14th Ave N, CIE 201, Fargo, North Dakota 58102, USA.
| | - Thomas DeSutter
- Department of Soil Science, North Dakota State University, Fargo, North Dakota 58108, USA
| | - Syeed Md Iskander
- Department of Civil, Construction and Environmental Engineering, North Dakota State University, 1410 14th Ave N, CIE 201, Fargo, North Dakota 58102, USA.
- Environmental and Conservation Sciences, North Dakota State University, 1410 14th Ave N, CIE 201, Fargo, North Dakota 58108, USA
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Pickard HM, Haque F, Sunderland EM. Bioaccumulation of Perfluoroalkyl Sulfonamides (FASA). ENVIRONMENTAL SCIENCE & TECHNOLOGY LETTERS 2024; 11:350-356. [PMID: 38645703 PMCID: PMC11027762 DOI: 10.1021/acs.estlett.4c00143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/23/2024]
Abstract
Hundreds of sites across the United States have high concentrations of perfluoroalkyl sulfonamides (FASA), but little is known about their propensity to accumulate in fish. FASA are precursors to terminal per- and polyfluoroalkyl substances (PFAS) that are abundant in diverse consumer products and aqueous film-forming foams manufactured using electrochemical fluorination (ECF AFFF). In this study, FASA with C3-C8 carbon chain lengths were detected in all fish samples from surface waters up to 8 km downstream of source zones with ECF AFFF contamination. Short-chain FASA ≤ C6 have rarely been included in routine screening for PFAS, but availability of new standards makes such analyses more feasible. Bioaccumulation factors (BAF) for FASA were between 1 and 3 orders of magnitude greater than their terminal perfluoroalkyl sulfonates. Across fish species, BAF for FASA were greater than for perfluorooctanesulfonate (PFOS), which is presently the focus of national advisory programs. Similar concentrations of the C6 FASA (<0.36-175 ng g-1) and PFOS (0.65-222 ng g-1) were detected in all fish species. No safety thresholds have been established for FASA. However, high concentrations in fish next to contaminated sites and preliminary findings on toxicity suggest an urgent need for consideration by fish advisory programs.
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Affiliation(s)
- Heidi M Pickard
- Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, United States
| | - Faiz Haque
- Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, United States
| | - Elsie M Sunderland
- Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, United States; Department of Environmental Health, Harvard T.H. Chan School of Public Health, Harvard University, Boston, Massachusetts 02115, United States
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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: 0] [Impact Index Per Article: 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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Ayodele A, Obeng-Gyasi E. Exploring the Potential Link between PFAS Exposure and Endometrial Cancer: A Review of Environmental and Sociodemographic Factors. Cancers (Basel) 2024; 16:983. [PMID: 38473344 DOI: 10.3390/cancers16050983] [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: 12/15/2023] [Revised: 02/01/2024] [Accepted: 02/27/2024] [Indexed: 03/14/2024] Open
Abstract
This exploratory narrative review paper delves into the intricate interplay between per- and polyfluoroalkyl substances (PFAS) exposure, sociodemographic factors, and the influence of stressors in the context of endometrial cancer. PFAS, ubiquitous environmental contaminants notorious for their persistence in the ecosystem, have garnered attention for their potential to disrupt endocrine systems and provoke immune responses. We comprehensively examine the various sources of PFAS exposure, encompassing household items, water, air, and soil, thus shedding light on the multifaceted routes through which individuals encounter these compounds. Furthermore, we explore the influence of sociodemographic factors, such as income, education, occupation, ethnicity/race, and geographical location and their relationship to endometrial cancer risk. We also investigated the role of stress on PFAS exposure and endometrial cancer risk. The results revealed a significant impact of sociodemographic factors on both PFAS levels and endometrial cancer risk. Stress emerged as a notable contributing factor influencing PFAS exposure and the development of endometrial cancer, further emphasizing the importance of stress management practices for overall well-being. By synthesizing evidence from diverse fields, this review underscores the need for interdisciplinary research and targeted interventions to comprehensively address the complex relationship between PFAS, sociodemographic factors, stressors, and endometrial cancer.
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Affiliation(s)
- Aderonke Ayodele
- Department of Built Environment, North Carolina A&T State University, Greensboro, NC 27411, USA
- Environmental Health and Disease Laboratory, North Carolina A&T State University, Greensboro, NC 27411, USA
| | - Emmanuel Obeng-Gyasi
- Department of Built Environment, North Carolina A&T State University, Greensboro, NC 27411, USA
- Environmental Health and Disease Laboratory, North Carolina A&T State University, Greensboro, NC 27411, USA
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7
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Das TK, Han Z, Banerjee S, Raoelison OD, Adeleye AS, Mohanty SK. PFAS release from the subsurface and capillary fringe during managed aquifer recharge. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2024; 343:123166. [PMID: 38110050 DOI: 10.1016/j.envpol.2023.123166] [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: 10/07/2023] [Revised: 11/24/2023] [Accepted: 12/12/2023] [Indexed: 12/20/2023]
Abstract
Managed aquifer recharge (MAR) is a sustainable way of harvesting groundwater in water-stressed urbanized areas, where reclaimed wastewater or stormwater is applied on a large basin to infiltrate water into the groundwater aquifer naturally. This process could rapidly fluctuate the water table and move the capillary fringe boundary, and the change in flow dynamic and associated geochemical changes could trigger the release of sequestered pollutants, including per- and polyfluoroalkyl substances (PFAS), also known as 'forever chemicals', from the subsurface and capillary fringe. Yet, the potential of PFAS release from the subsurface and capillary zone during recharge events when the water table rapidly fluctuates has not been evaluated. This study uses laboratory column experiments to simulate PFAS release from pre-contaminated subsurface and capillary fringe during groundwater table fluctuation. The results reveal that the groundwater level fluctuations during MAR increased the release of perfluorobutanesulfonic acid (PFBS) and perfluorooctanesulfonic acid (PFOS) from the capillary fringe, but the fraction released depended on PFAS type and their association with soil colloids. A higher proportion of PFOS in column effluent was found to be associated with particles, while a greater portion of released PFBS was in a free or dissolved state. The direction of water table fluctuation did not affect the release of PFAS in this study. A lack of change in the concentration of bromide, a conservative tracer, during flow interruption, indicates that diffusion of PFAS through reconnected pores during water table rise had an insignificant effect on PFAS release. Overall, this study provides insights into how PFAS can be released from the subsurface and capillary fringe during managed aquifer recharge when the groundwater level is expected to fluctuate quickly.
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Affiliation(s)
- Tonoy K Das
- Civil and Environmental Engineering, University of California Los Angeles, Los Angeles, USA.
| | - Ziwei Han
- Civil and Environmental Engineering, University of California Irvine, Irvine, CA, USA
| | - Swapnil Banerjee
- Civil and Environmental Engineering, University of California Los Angeles, Los Angeles, USA
| | - Onja D Raoelison
- Civil and Environmental Engineering, University of California Los Angeles, Los Angeles, USA
| | - Adeyemi S Adeleye
- Civil and Environmental Engineering, University of California Irvine, Irvine, CA, USA
| | - Sanjay K Mohanty
- Civil and Environmental Engineering, University of California Los Angeles, Los Angeles, USA.
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Wanzek TA, Field JA, Kostarelos K. Repeated Aqueous Film-Forming Foams Applications: Impacts on Polyfluoroalkyl Substances Retention in Saturated Soil. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:1659-1668. [PMID: 38198694 DOI: 10.1021/acs.est.3c04595] [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: 01/12/2024]
Abstract
Historical practices at firefighter-training areas involved repeated aqueous film-forming foams (AFFFs) applications, resulting in source zones characterized by high concentrations of perfluoroalkyl and polyfluoroalkyl substances (PFAS). Repeated applications of AFFF composed of 14 anionic and 23 zwitterionic perfluoroalkyl substances (PFAS) were conducted on a single one-dimensional saturated soil column to quantify PFAS retention. An electrofluorination-based (3M) Milspec AFFF, which was above the mixture's critical micelle concentration (CMC), was at application strength (3%, v/v). Retention and retardation of PFAS mass increased with each successive AFFF addition, although the PFAS concentration profiles for subsequent applications differed from the initial. Greater degree of mass retention and retardation correlated with longer PFAS carbon-fluorine chain length and charged-headgroup type and as a function of AFFF application number. Anionic PFAS were increasingly retained with each subsequent AFFF application, while zwitterionic PFAS exhibited an alternating pattern of sorption and desorption. Surfactant-surfactant adsorption and competition during repeat AFFF applications that are at concentrations above the CMC resulted in adsorbed PFAS from the first application, changing the nature of the soil surface with preferential sorption of anionic PFAS and release of zwitterionic PFAS due to competitive elution. Applying a polyparameter quantitative structure-property relationship developed to describe sorption of AFFF-derived PFAS to uncontaminated, saturated soil was attempted for our experimental conditions. The model had been derived for data where AFFF is below the apparent CMC and our experimental conditions that included the presence of mixed micelles (aggregates consisting of different kinds of surfactants that exhibit characteristics properties different from micelles composed of a single surfactant) resulted in overall PFAS mass retained by an average of 27.3% ± 2.7% (standard error) above the predicted values. The correlation was significantly improved by adding a "micelle parameter" to account for cases where the applied AFFF was above the apparent CMC. Our results highlight the importance of interactions between the AFFF components that can only be investigated by employing complex PFAS mixtures at concentrations present in actual AFFF at application strength, which are above their apparent CMC. In firefighter-training areas (AFFF source zones), competitive desorption of PFAS may result in downgradient PFAS retention when desorbed PFAS become resorbed to uncontaminated soil.
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Affiliation(s)
- Thomas A Wanzek
- Department of Crop and Soil Science, Oregon State University, Corvallis, Oregon 97331, United States
| | - Jennifer A Field
- Department Environmental and Molecular Toxicology, Oregon State University, Corvallis, Oregon 97331, United States
| | - Konstantinos Kostarelos
- UH Energy Technology Innovation Center, University of Houston, Houston, Texas 77204, United States
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Umeh AC, Hassan M, Egbuatu M, Zeng Z, Al Amin M, Samarasinghe C, Naidu R. Multicomponent PFAS sorption and desorption in common commercial adsorbents: Kinetics, isotherm, adsorbent dose, pH, and index ion and ionic strength effects. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 904:166568. [PMID: 37633378 DOI: 10.1016/j.scitotenv.2023.166568] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2023] [Revised: 08/23/2023] [Accepted: 08/23/2023] [Indexed: 08/28/2023]
Abstract
The adsorption and desorption of 9 PFAS, including 3 perfluoroalkyl sulphonic and 6 perfluoroalkyl carboxylic acids, in artificial groundwater was investigated using 3 commercial adsorbents that comprised a powdered activated carbon (PAC), a surface-modified organoclay (NMC+n), and a carbonaceous organic amendment (ROAC). Sorption kinetics and isotherms of PFAS, as well as the effects of adsorbent dose, pH, index ion and ionic strength on PFAS adsorption and desorption were investigated. Sorption of multicomponent PFAS in the adsorbents was rapid, especially for NMC+n and ROAC, regardless of PFAS chain length. The sorption and (and especially) desorption of PFAS in the adsorbents was impacted by the pH, index ion, and ionic strength of simulated groundwater, especially for the short chain PFAS, with only minimal impacts on NMC+n and PAC compared to ROAC. Although the potential mineral and charged constituents of the adsorbents contributed to the adsorption of short chain PFAS through electrostatic interactions, these interactions were susceptible to variable groundwater chemistry. Hydrophobic interactions also played a major role in facilitating and increasing PFAS sorption, especially in adsorbents with aliphatic functional groups. The desorption of PFAS from the adsorbents was below 8 % when the aqueous phase was deionised water, with no measurable desorption for NMC+n. In contrast, the desorption of short chain PFAS in simulated groundwater increased substantially (30-100 %) in the adsorbents, especially in ROAC and NMC+n, but more so with ROAC. In general, the three adsorbents exhibited strong stability for the long chain PFAS, especially the perfluoroalkyl sulphonic acids, with minimal to no sorption reversibility under different pH and ionic composition of simulated groundwater. This study highlights the importance of understanding not only the sorption of PFAS in groundwater using adsorbents, but also the desorption of PFAS, which may be useful for decision making during the ex-situ and in-situ treatment of PFAS-contaminated groundwater.
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Affiliation(s)
- Anthony C Umeh
- Global Centre for Environmental Remediation (GCER), The University of Newcastle, Callaghan, NSW 2308, Australia; crcCARE, The University of Newcastle, Callaghan, NSW 2308, Australia
| | - Masud Hassan
- Global Centre for Environmental Remediation (GCER), The University of Newcastle, Callaghan, NSW 2308, Australia
| | - Maureen Egbuatu
- Global Centre for Environmental Remediation (GCER), The University of Newcastle, Callaghan, NSW 2308, Australia
| | - Zijun Zeng
- Global Centre for Environmental Remediation (GCER), The University of Newcastle, Callaghan, NSW 2308, Australia
| | - Md Al Amin
- Global Centre for Environmental Remediation (GCER), The University of Newcastle, Callaghan, NSW 2308, Australia
| | - Chamila Samarasinghe
- Global Centre for Environmental Remediation (GCER), The University of Newcastle, Callaghan, NSW 2308, Australia; crcCARE, The University of Newcastle, Callaghan, NSW 2308, Australia
| | - Ravi Naidu
- Global Centre for Environmental Remediation (GCER), The University of Newcastle, Callaghan, NSW 2308, Australia; crcCARE, The University of Newcastle, Callaghan, NSW 2308, Australia.
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Zhao M, Yao Y, Dong X, Baqar M, Fang B, Chen H, Sun H. Nontarget Identification of Novel Per- and Polyfluoroalkyl Substances (PFAS) in Soils from an Oil Refinery in Southwestern China: A Combined Approach with TOP Assay. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:20194-20205. [PMID: 37991390 DOI: 10.1021/acs.est.3c05859] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2023]
Abstract
Oil refinery activity can be an emission source of perfluoroalkyl and polyfluoroalkyl substances (PFAS) to the environment, while the contamination profiles in soils remain unknown. This study investigated 44 target PFAS in soil samples collected from an oil refinery in Southeastern China, identified novel PFAS, and characterized their behaviors by assessing their changes before and after employing advanced oxidation using a combination of nontarget analysis and a total oxidizable precursor (TOP) assay. Thirty-four target PFAS were detected in soil samples. Trifluoroacetic acid (TFA) and hexafluoropropylene oxide dimer acid (HFPO-DA) were the dominant PFAS. Twenty-three novel PFAS of 14 classes were identified, including 8 precursors, 11 products, and 4 stable PFAS characterized by the TOP assay. Particularly, three per-/polyfluorinated alcohols were identified for the first time, and hexafluoroisopropanol (HFIP) quantified up to 657 ng/g dw is a novel precursor for TFA. Bistriflimide (NTf2) potentially associated with an oil refinery was also reported for the first time in the soil samples. This study highlighted the advantage of embedding the TOP assay in nontarget analysis to reveal not only the presence of unknown PFAS but also their roles in environmental processes. Overall, this approach provides an efficient way to uncover contamination profiles of PFAS especially in source-impacted areas.
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Affiliation(s)
- Maosen Zhao
- MOE Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, Tianjin 300071, People's Republic of China
| | - Yiming Yao
- MOE Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, Tianjin 300071, People's Republic of China
| | - Xiaoyu Dong
- MOE Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, Tianjin 300071, People's Republic of China
| | - Mujtaba Baqar
- MOE Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, Tianjin 300071, People's Republic of China
- Sustainable Development Study Centre, Government College University, Lahore 54000, Pakistan
| | - Bo Fang
- MOE Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, Tianjin 300071, People's Republic of China
| | - Hao Chen
- MOE Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, Tianjin 300071, People's Republic of China
| | - Hongwen Sun
- MOE Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, Tianjin 300071, People's Republic of China
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11
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Liu J, Zhao Z, Li J, Hua X, Zhang B, Tang C, An X, Lin T. Emerging and legacy perfluoroalkyl and polyfluoroalkyl substances (PFAS) in surface water around three international airports in China. CHEMOSPHERE 2023; 344:140360. [PMID: 37816443 DOI: 10.1016/j.chemosphere.2023.140360] [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: 08/16/2023] [Revised: 09/30/2023] [Accepted: 10/02/2023] [Indexed: 10/12/2023]
Abstract
Perfluoroalkyl and polyfluoroalkyl substances (PFAS) are a large category of crucial environmental contaminants of global concerns. There are limited data on PFAS in surface water around international airports in China. The present study investigated the concentrations, distributions, and sources of emerging and legacy PFAS in surface waters around Beijing Capital International Airport (BC), Shanghai Pudong International Airport (SP), and Guangzhou Baiyun International Airport (GB) in China. Twenty-seven target compounds were quantified. The Σ27PFAS concentrations ranged from 19.0 to 62.8 ng/L (mean 36.1 ng/L) in BC, 25.6-342 ng/L (mean 76.0 ng/L) in SP, 7.35-72.7 ng/L (mean 21.6 ng/L) in GB. The dominant compound was perfluorooctanoic acid (PFOA), which accounted for an average of 27% (5%-65%) of the Σ27PFAS concentrations. The alternatives with -C6F12- group had detection frequencies ranging from 72% to 100%. The partition coefficient results indicate that the longer chain PFAS (C > 8) tend to be more distributed in the particle phase. Fifty suspect and nontarget PFAS were identified. In GB, 44 PFAS were identified, more than SP of 39 and BC of 38. An ultra short-chain (C = 2) precursor, N-methylperfluoroethanesulfonamido acetic acid (MeFEtSAA), was identified and semi-quantified. Domestic wastewater discharges might be the main sources around BC, while industrial and aviation activities might be the main sources around SP and GB.
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Affiliation(s)
- Jing Liu
- College of Marine Ecology and Environment, Shanghai Ocean University, Shanghai, 201306, China
| | - Zhen Zhao
- College of Marine Ecology and Environment, Shanghai Ocean University, Shanghai, 201306, China.
| | - Jie Li
- College of Marine Ecology and Environment, Shanghai Ocean University, Shanghai, 201306, China
| | - Xia Hua
- Handan Ecology and Environment Bureau, Hebei, 056008, China
| | - Boxuan Zhang
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China
| | - Caijun Tang
- College of Marine Ecology and Environment, Shanghai Ocean University, Shanghai, 201306, China
| | - Xinyi An
- College of Marine Ecology and Environment, Shanghai Ocean University, Shanghai, 201306, China
| | - Tian Lin
- College of Marine Ecology and Environment, Shanghai Ocean University, Shanghai, 201306, China
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12
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Bierbaum T, Hansen SK, Poudel B, Haslauer C. Investigating rate-limited sorption, sorption to air-water interfaces, and colloid-facilitated transport during PFAS leaching. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:121529-121547. [PMID: 37957494 PMCID: PMC10724089 DOI: 10.1007/s11356-023-30811-2] [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: 06/21/2023] [Accepted: 10/28/2023] [Indexed: 11/15/2023]
Abstract
Various sorption processes affect leaching of per- and polyfluoroalkyl substances (PFAS) such as PFOA and PFOS. The objectives of this study are to (1) compare rate-limited leaching in column and lysimeter experiments, (2) investigate the relevance of sorption to air-water interfaces (AWI), and (3) examine colloid-facilitated transport as a process explaining early experimental breakthrough. A continuum model (CM) with two-domain sorption is used to simulate equilibrium and rate-limited sorption. A random walk particle tracking (PT) model was developed and applied to analyze complex leaching characteristics. Results show that sorption parameters derived from column experiments underestimate long-term PFOA leaching in lysimeter experiments due to early depletion, suggesting that transformation of precursors contributes to the observed long-term leaching in the lysimeters (approximately 0.003 µg/kg/d PFOA). Both models demonstrate that sorption to AWI is the dominant retention mechanism for PFOS in lysimeter experiments, with retardation due to AWI being 3 (CM) to 3.7 (PT) times higher than retardation due to solid phase sorption. Notably, despite a simplified conception of AWI sorption, the PT results are closer to the observations. The PT simulations demonstrate possible colloid-facilitated transport at early time; however, results using substance-specific varying transport parameters align better with the observations, which should be equal if colloid-facilitated transport without additional kinetics is the sole mechanism affecting early breakthrough. Possibly, rate-limited sorption to AWI is relevant during the early stages of the lysimeter experiment. Our findings demonstrate that rate-limited sorption is less relevant for long-term leaching under field conditions compared to transformation of precursors and that sorption to AWI can be the dominant retention mechanism on contaminated sites. Moreover, they highlight the potential of random walk particle tracking as a practical alternative to continuum models for estimating the relative contributions of various retention mechanisms.
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Affiliation(s)
- Thomas Bierbaum
- Research Facility for Subsurface Remediation (VEGAS), University of Stuttgart, Institute for Modelling Environmental Systems (IWS), Pfaffenwaldring 61, 70569, Stuttgart, Germany.
| | - Scott K Hansen
- Ben-Gurion University of the Negev, Zuckerberg Institute for Water Research, 8499000, Midreshet Ben-Gurion, Israel
| | - Bikash Poudel
- Research Facility for Subsurface Remediation (VEGAS), University of Stuttgart, Institute for Modelling Environmental Systems (IWS), Pfaffenwaldring 61, 70569, Stuttgart, Germany
| | - Claus Haslauer
- Research Facility for Subsurface Remediation (VEGAS), University of Stuttgart, Institute for Modelling Environmental Systems (IWS), Pfaffenwaldring 61, 70569, Stuttgart, Germany
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13
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Röhler K, Susset B, Grathwohl P. Production of perfluoroalkyl acids (PFAAs) from precursors in contaminated agricultural soils: Batch and leaching experiments. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 902:166555. [PMID: 37633401 DOI: 10.1016/j.scitotenv.2023.166555] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Revised: 08/22/2023] [Accepted: 08/23/2023] [Indexed: 08/28/2023]
Abstract
Contamination of soils with per- and polyfluoroalkyl substances (PFAS) (e.g., aqueous film forming foams (AFFFs) or PFAS containing biosolids applied to agricultural soils) can lead to large scale groundwater pollution. For site management, knowledge about the extent and time scales of PFAS contamination is crucial. At such sites, often persistent perfluoroalkyl acids (PFAAs) and so-called precursors, which can be transformed into PFAAs, co-occur. In this study, the release of PFAAs from 14 soil samples from an agricultural site in southwest Germany contaminated via compost/paper sludge was investigated. Rapid leaching of C4-C8 perfluoroalkyl carboxylic acids (PFCA) was observed in saturated column tests, while slowing down with increasing chain-length (≥ C9 PFCAs). Two selected samples were further incubated in batch-tests after removal of existing C4-C8 PFCAs in extensive column leaching tests until a liquid-solid ratio of 10 l/kg. During 60 days of incubation, aqueous concentrations of C4-C8 PFCAs increased linearly by a factor of 29-222, indicating continuous production by transformation of precursors. The potential PFAA-precursor reservoir was estimated by the direct total oxidizable precursor (dTOP) assay. PFCA concentrations after the dTOP increased up to two orders of magnitude. Production rates determined in batch-tests combined with the results of dTOP assay were used to estimate time scales for the duration of C4-C8 PFCAs emission from the contaminated agricultural soils which likely will last for several decades.
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Affiliation(s)
- Klaus Röhler
- Department of Geosciences, University of Tübingen, Schnarrenbergstraße 94-96, 72076 Tübingen, Germany
| | - Bernd Susset
- Department of Geosciences, University of Tübingen, Schnarrenbergstraße 94-96, 72076 Tübingen, Germany
| | - Peter Grathwohl
- Department of Geosciences, University of Tübingen, Schnarrenbergstraße 94-96, 72076 Tübingen, Germany.
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Al Amin M, Luo Y, Shi F, Yu L, Liu Y, Nolan A, Awoyemi OS, Megharaj M, Naidu R, Fang C. A modified TOP assay to detect per- and polyfluoroalkyl substances in aqueous film-forming foams (AFFF) and soil. Front Chem 2023; 11:1141182. [PMID: 37881243 PMCID: PMC10595011 DOI: 10.3389/fchem.2023.1141182] [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: 01/10/2023] [Accepted: 09/25/2023] [Indexed: 10/27/2023] Open
Abstract
Total oxidisable precursor (TOP) assay can oxidise some per- and polyfluoroalkyl substances (PFASs) and their precursors, most of which cannot be quantitatively detected so far, and convert them to detectable PFASs, such as perfluoroalkyl acids (PFAAs). However, the conversion is constrained by the complexity of the target samples, including co-existent organics, unknown PFAS precursors, and background. In this study, the TOP assay is modified to increase the oxidation and conversion efficiency by changing the initial concentration of target sample, increasing oxidising doses, time, temperature, etc. The modified TOP assay is applied to test several aqueous film-forming foams (AFFF) and a PFAS-contaminated soil extract. The sum concentrations of the detectable PFASs are increased by up to ∼534× in the AFFF samples and ∼7× in the PFAS-contaminated soil extract. The detectable fluorotelomer sulfonate (FTS, such as 6:2/8:2 FTS) is accounted as an oxidation indicator to monitor the oxidation and conversion progress of the oxidisable PFASs precursors to the detectable PFASs. Overall, the modified TOP assay could be an appropriate method for identifying missing PFASs mass in complex matrices by detecting the PFASs precursors effectively.
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Affiliation(s)
- Md. Al Amin
- Global Centre for Environmental Remediation (GCER), University of Newcastle, Callaghan, NSW, Australia
- CRC for Contamination Assessment and Remediation of the Environment (CRC CARE), University of Newcastle, Callaghan, NSW, Australia
| | - Yunlong Luo
- Global Centre for Environmental Remediation (GCER), University of Newcastle, Callaghan, NSW, Australia
- CRC for Contamination Assessment and Remediation of the Environment (CRC CARE), University of Newcastle, Callaghan, NSW, Australia
| | - Feng Shi
- Global Centre for Environmental Remediation (GCER), University of Newcastle, Callaghan, NSW, Australia
- CRC for Contamination Assessment and Remediation of the Environment (CRC CARE), University of Newcastle, Callaghan, NSW, Australia
| | - Linbo Yu
- Global Centre for Environmental Remediation (GCER), University of Newcastle, Callaghan, NSW, Australia
- CRC for Contamination Assessment and Remediation of the Environment (CRC CARE), University of Newcastle, Callaghan, NSW, Australia
| | - Yanju Liu
- Global Centre for Environmental Remediation (GCER), University of Newcastle, Callaghan, NSW, Australia
- CRC for Contamination Assessment and Remediation of the Environment (CRC CARE), University of Newcastle, Callaghan, NSW, Australia
| | | | - Olalekan Simon Awoyemi
- Global Centre for Environmental Remediation (GCER), University of Newcastle, Callaghan, NSW, Australia
| | - Mallavarapu Megharaj
- Global Centre for Environmental Remediation (GCER), University of Newcastle, Callaghan, NSW, Australia
- CRC for Contamination Assessment and Remediation of the Environment (CRC CARE), University of Newcastle, Callaghan, NSW, Australia
| | - Ravi Naidu
- Global Centre for Environmental Remediation (GCER), University of Newcastle, Callaghan, NSW, Australia
- CRC for Contamination Assessment and Remediation of the Environment (CRC CARE), University of Newcastle, Callaghan, NSW, Australia
| | - Cheng Fang
- Global Centre for Environmental Remediation (GCER), University of Newcastle, Callaghan, NSW, Australia
- CRC for Contamination Assessment and Remediation of the Environment (CRC CARE), University of Newcastle, Callaghan, NSW, Australia
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15
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Niarchos G, Georgii L, Ahrens L, Kleja DB, Fagerlund F. A systematic study of the competitive sorption of per- and polyfluoroalkyl substances (PFAS) on colloidal activated carbon. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2023; 264:115408. [PMID: 37666203 DOI: 10.1016/j.ecoenv.2023.115408] [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: 03/13/2023] [Revised: 07/30/2023] [Accepted: 08/24/2023] [Indexed: 09/06/2023]
Abstract
Treatment of environmental media contaminated with per- and polyfluoroalkyl substances (PFAS) is crucial to mitigate mounting health risks associated with exposure. Colloidal activated carbon (CAC) has shown promise in treating contaminated soils, but understanding the interaction among PFAS during sorption is necessary for optimal remediation. This study investigated the extent to which PFAS of varying chain lengths and functional groups compete for sorption to CAC. Batch tests were conducted with natural soil and spiked water, using CAC at 0.2% w/w to remove seven PFAS with individual starting concentrations up to 0.05 mmol L-1. PFAS sorption to CAC was evaluated in three systems: a composite mixture of all studied compounds, a binary-solute system, and a single-solute system. The sorption experiments exhibited strong PFAS affinity to CAC, with removal rates between 41% and 100%, and solid/liquid partition coefficients (Kd) between 10 and 104 L kg-1. Differences were noticed among the various spiking mixtures, based on perfluorocarbon chain length, functional group, and the starting PFAS concentrations. Competition effects were detected when PFAS were in a multi-solute system, with an average 10% drop in removal, which can evidently become more relevant at higher concentrations, due to the observed non-linearity of the sorption process. The PFAS most vulnerable to competition effects in multi-solute systems were the short-chain perfluoropentanoic acid (PFPeA) and perfluorobutane sulfonic acid (PFBS), with an up to 25% reduction in removal. In bi-solute systems, perfluorooctane sulfonamide (FOSA) dominated over its ionisable counterparts, i.e. perfluorooctane sulfonic acid (PFOS) and perfluorononanoic acid (PFNA), indicating the importance of hydrophobic effects or layer formation in the sorption process. These results underscore the importance of considering competition in PFAS sorption processes when designing and implementing remediation techniques for PFAS-contaminated media.
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Affiliation(s)
- Georgios Niarchos
- Department of Earth Sciences, Uppsala University, P.O. Box 256, SE-751 05 Uppsala, Sweden.
| | - Linnea Georgii
- 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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16
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Pritchard JC, Cho YM, Hawkins KM, Spahr S, Higgins CP, Luthy RG. Predicting PFAS and Hydrophilic Trace Organic Contaminant Transport in Black Carbon-Amended Engineered Media Filters for Improved Stormwater Runoff Treatment. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:14417-14428. [PMID: 37699564 PMCID: PMC10537446 DOI: 10.1021/acs.est.3c01260] [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: 09/14/2023]
Abstract
Improved stormwater treatment is needed to prevent toxic and mobile contaminant transport into receiving waters and allow beneficial use of stormwater runoff. In particular, safe capture of stormwater runoff to augment drinking water supplies is contingent upon removing dissolved trace organic contaminants (TrOCs) not captured by conventional stormwater control measures. This study builds upon a prior laboratory-based column study investigating biochar and regenerated activated carbon (RAC) amendment for removing hydrophilic trace organic contaminants (HiTrOCs) and poly- and perfluoroalkyl substances (PFASs) from stormwater runoff. A robust contaminant transport model framework incorporating time-dependent flow and influent concentration is developed and validated to predict HiTrOC and PFAS transport in biochar- and RAC-amended stormwater filters. Specifically, parameters fit using a sorption-retarded intraparticle pore diffusion transport model were validated using data further along the depth of the column and compared to equilibrium batch isotherms. The transport model and fitted parameters were then used to estimate the lifetime of a hypothetical stormwater filter in Seal Beach, CA, to be 35 ± 6 years for biochar- and 51 ± 17 years for RAC-amended filters, under ideal conditions with no filter clogging. This work offers insights on the kinetics of HiTrOC and PFAS transport within biochar and RAC filters and on the impact of filter design on contaminant removal performance and longevity.
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Affiliation(s)
- James Conrad Pritchard
- Re-inventing the Nation's Urban Water Infrastructure (ReNUWIt), National Science Foundation Engineering Research Center, Stanford, California 94305, United States
- Department of Civil & Environmental Engineering, Stanford University, Stanford, California 94305, United States
| | - Yeo-Myoung Cho
- Re-inventing the Nation's Urban Water Infrastructure (ReNUWIt), National Science Foundation Engineering Research Center, Stanford, California 94305, United States
- Department of Civil & Environmental Engineering, Stanford University, Stanford, California 94305, United States
| | - Kathleen Mills Hawkins
- Re-inventing the Nation's Urban Water Infrastructure (ReNUWIt), National Science Foundation Engineering Research Center, Stanford, California 94305, United States
- Department of Civil & Environmental Engineering, Colorado School of Mines, Golden, Colorado 80401, United States
| | - Stephanie Spahr
- Re-inventing the Nation's Urban Water Infrastructure (ReNUWIt), National Science Foundation Engineering Research Center, Stanford, California 94305, United States
- Department of Ecohydrology and Biogeochemistry, Leibniz Institute of Freshwater Ecology and Inland Fisheries (IGB), 12587 Berlin, Germany
| | - Christopher P Higgins
- Re-inventing the Nation's Urban Water Infrastructure (ReNUWIt), National Science Foundation Engineering Research Center, Stanford, California 94305, United States
- Department of Civil & Environmental Engineering, Colorado School of Mines, Golden, Colorado 80401, United States
| | - Richard G Luthy
- Re-inventing the Nation's Urban Water Infrastructure (ReNUWIt), National Science Foundation Engineering Research Center, Stanford, California 94305, United States
- Department of Civil & Environmental Engineering, Stanford University, Stanford, California 94305, United States
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17
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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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18
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Kabiri S, Navarro DA, Hamad SA, Grimison C, Higgins CP, Mueller JF, Kookana RS, McLaughlin MJ. Physical and chemical properties of carbon-based sorbents that affect the removal of per- and polyfluoroalkyl substances from solution and soil. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 875:162653. [PMID: 36894096 DOI: 10.1016/j.scitotenv.2023.162653] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Revised: 02/12/2023] [Accepted: 03/01/2023] [Indexed: 06/18/2023]
Abstract
Removal of per- and polyfluoroalkyl substances (PFASs) from water or their immobilization in soil using carbon-based sorbents is one of the cost-effective techniques. Considering the variety of carbon-based sorbents, identifying the key sorbent properties responsible for PFASs removal from solution or immobilization in the soil can assist in the selection of the best sorbents for management of contaminated sites. This study evaluated the performance of 28 carbon-based sorbents including granular and powdered activated carbon (GAC and PAC), mixed mode carbon mineral material, biochars, and graphene-based materials (GNBs). The sorbents were characterized for a range of physical and chemical properties. PFASs' sorption from an AFFF-spiked solution was examined via a batch experiment, while their ability to immobilize PFASs in soil was tested following mixing, incubation and extraction using the Australian Standard Leaching Procedure. Both soil and solution were treated with 1 % w/w sorbents. Comparing different carbon-based materials, PAC, mixed mode carbon mineral material and GAC were the most effective in sorbing PFASs in both solution and soil. Among the different physical characteristics measured, the sorption of long-chain and more hydrophobic PFASs in both soil and solution was best correlated with sorbent surface area measured using methylene blue, which highlights the importance of mesopores in PFASs sorption. Iodine number was found to be a better indicator of the sorption of short-chain and more hydrophilic PFASs from solution but was found to be poorly correlated with PFASs immobilization in soil for activated carbons. Sorbents with a net positive charge performed better than those with a net negative charge, or no net charge. This study showed that surface area measured by methylene blue and surface charge are the best indicators of sorbent performance with respect to sorption/reducing leaching of PFASs. These properties may be helpful in selecting sorbents for PFASs remediation of soils/waters.
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Affiliation(s)
- Shervin Kabiri
- School of Agriculture, Food and Wine, The University of Adelaide, Waite Campus, PMB1, Glen Osmond, South Australia 5064, Australia.
| | | | - Suhair Ahmed Hamad
- School of Agriculture, Food and Wine, The University of Adelaide, Waite Campus, PMB1, Glen Osmond, South Australia 5064, Australia
| | | | - Christopher P Higgins
- Department of Civil and Environmental Engineering, Colorado School of Mines, Golden, CO 80401, USA
| | - Jochen F Mueller
- Queensland Alliance for Environmental Health Sciences (QAEHS), The University of Queensland, Brisbane, Queensland 4102, Australia
| | - Rai S Kookana
- CSIRO Land and Water, PMB 2, Glen Osmond, SA 5064, Australia
| | - Michael J McLaughlin
- School of Agriculture, Food and Wine, The University of Adelaide, Waite Campus, PMB1, Glen Osmond, South Australia 5064, Australia
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19
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Hubert M, Arp HPH, Hansen MC, Castro G, Meyn T, Asimakopoulos AG, Hale SE. Influence of grain size, organic carbon and organic matter residue content on the sorption of per- and polyfluoroalkyl substances in aqueous film forming foam contaminated soils - Implications for remediation using soil washing. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 875:162668. [PMID: 36894086 DOI: 10.1016/j.scitotenv.2023.162668] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Revised: 02/24/2023] [Accepted: 03/02/2023] [Indexed: 06/18/2023]
Abstract
A soil that was historically contaminated with Aqueous Film Forming Foam (AFFF) was dry sieved into size fractions representative of those produced during soil washing. Batch sorption tests were then conducted to investigate the effect of soil parameters on in situ per- and polyfluoroalkyl substances (PFAS) sorption of these different size fractions: < 0.063 mm, 0.063 to 0.5 mm, 0.5 to 2 mm, 2 to 4 mm, 4 to 8 mm, and soil organic matter residues (SOMR). PFOS (513 ng/g), 6:2 FTS (132 ng/g) and PFHxS (58 ng/g) were the most dominant PFAS in the AFFF contaminated soil. Non-spiked, in situ Kd values for 19 PFAS ranged from 0.2 to 138 L/Kg (log Kd -0.8 to 2.14) for the bulk soil and were dependant on the head group and perfluorinated chain length (spanning C4 to C13). The Kd values increased with decreasing grain size and increasing organic carbon content (OC), which were correlated to each other. For example, the PFOS Kd value for silt and clay (< 0.063 mm, 17.1 L/Kg, log Kd 1.23) were approximately 30 times higher compared to the gravel fraction (4 to 8 mm, 0.6 L/Kg, log Kd -0.25). The highest PFOS Kd value (116.6 L/Kg, log Kd 2.07) was found for the SOMR fraction, which had the highest OC content. Koc values for PFOS ranged from 6.9 L/Kg (log Koc 0.84) for the gravel fraction to 1906 L/Kg (log Koc 3.28) for the silt and clay, indicating that the mineral composition of the different size fractions also influenced sorption. The results here emphasize the need to separate coarse-grained fractions and fine-grained fractions, and in particular the SOMR, to optimize the soil washing process. Higher Kd values for the smaller size fractions indicate that coarser soils are better suited for soil washing.
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Affiliation(s)
- Michel Hubert
- Norwegian University of Science and Technology (NTNU), NO-7491 Trondheim, Norway; Norwegian Geotechnical Institute (NGI), NO-0806 Oslo, Norway.
| | - Hans Peter H Arp
- Norwegian University of Science and Technology (NTNU), NO-7491 Trondheim, Norway; Norwegian Geotechnical Institute (NGI), NO-0806 Oslo, Norway
| | | | - Gabriela Castro
- Norwegian University of Science and Technology (NTNU), NO-7491 Trondheim, Norway
| | - Thomas Meyn
- Norwegian University of Science and Technology (NTNU), NO-7491 Trondheim, Norway
| | | | - Sarah E Hale
- Norwegian Geotechnical Institute (NGI), NO-0806 Oslo, Norway
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20
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Wanzek T, Stults JF, Johnson MG, Field JA, Kleber M. Role of Mineral-Organic Interactions in PFAS Retention by AFFF-Impacted Soil. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:5231-5242. [PMID: 36947878 PMCID: PMC10764056 DOI: 10.1021/acs.est.2c08806] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
A comprehensive, generalized approach to predict the retention of per- and polyfluoroalkyl substances (PFAS) from aqueous film-forming foam (AFFF) by a soil matrix as a function of PFAS molecular and soil physiochemical properties was developed. An AFFF with 34 major PFAS (12 anions and 22 zwitterions) was added to uncontaminated soil in one-dimensional saturated column experiments and PFAS mass retained was measured. PFAS mass retention was described using an exhaustive statistical approach to generate a poly-parameter quantitative structure-property relationship (ppQSPR). The relevant predictive properties were PFAS molar mass, mass fluorine, number of nitrogens in the PFAS molecule, poorly crystalline Fe oxides, organic carbon, and specific (BET-N2) surface area. The retention of anionic PFAS was nearly independent of soil properties and largely a function of molecular hydrophobicity, with the size of the fluorinated side chain as the main predictor. Retention of nitrogen-containing zwitterionic PFAS was related to poorly crystalline metal oxides and organic carbon content. Knowledge of the extent to which a suite of PFAS may respond to variations in soil matrix properties, as developed here, paves the way for the development of reactive transport algorithms with the ability to capture PFAS dynamics in source zones over extended time frames.
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Affiliation(s)
- Thomas Wanzek
- Department of Crop and Soil Science, Oregon State University, Corvallis, Oregon 97331, United States
| | - John F. Stults
- Department Civil and Environmental Engineering, Colorado School of Mines, Golden, Colorado, 80401, United States
| | - Mark G. Johnson
- U.S. Environmental Protection Agency, Center for Public Health and Environmental Assessment, Pacific Ecological Systems Division, Corvallis, Oregon 97333, United States
| | - Jennifer A. Field
- Department Environmental and Molecular Toxicology, Oregon State University, Corvallis, Oregon 97331, United States
| | - Markus Kleber
- Department of Crop and Soil Science, Oregon State University, Corvallis, Oregon 97331, United States
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21
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Nickerson A, Maizel AC, Schaefer CE, Ranville JF, Higgins CP. Effect of geochemical conditions on PFAS release from AFFF-impacted saturated soil columns. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2023; 25:405-414. [PMID: 36629138 DOI: 10.1039/d2em00367h] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Per- and polyfluoroalkyl substances (PFASs) are frequently found at high concentrations in the subsurface of aqueous film forming foam (AFFF)-impacted sites. Geochemical parameters affect the release of PFASs from source area soils into groundwater but have not been extensively studied for soils that have been historically impacted with AFFF. This study investigated the effects of pH and salt concentrations on release of anionic and zwitterionic PFASs from AFFF-impacted soils in flow-through saturated columns. High pH (10) columns with elevated sodium concentrations had higher cumulative masses eluted of several PFASs compared to pH 3 and pH 7 columns with lower sodium concentrations, likely caused by changes to soil organic matter surface charge. Four PFASs (e.g. 4:2 fluorotelomer sulfonate, perfluorobutane sulfonamido acetic acid) eluted significantly earlier in both pH 3 and pH 10/high NaCl columns compared to pH 7 columns. The results of this study suggest that shifts in pH for soils located at AFFF-impacted sites - particularly raising the pH - may mobilize sorbed PFASs, specifically longer-chain and zwitterionic compounds that are typically strongly sorbed to soil.
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Affiliation(s)
- Anastasia Nickerson
- Department of Civil and Environmental Engineering, Colorado School of Mines, Golden, Colorado 80401, USA.
| | - Andrew C Maizel
- Department of Civil and Environmental Engineering, Colorado School of Mines, Golden, Colorado 80401, USA.
| | | | - James F Ranville
- Department of Chemistry, Colorado School of Mines, Golden, Colorado 80401, USA
| | - Christopher P Higgins
- Department of Civil and Environmental Engineering, Colorado School of Mines, Golden, Colorado 80401, USA.
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22
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Yang N, Yang S, Ma Q, Beltran C, Guan Y, Morsey M, Brown E, Fernando S, Holsen TM, Zhang W, Yang Y. Solvent-Free Nonthermal Destruction of PFAS Chemicals and PFAS in Sediment by Piezoelectric Ball Milling. ENVIRONMENTAL SCIENCE & TECHNOLOGY LETTERS 2023; 10:198-203. [PMID: 37034438 PMCID: PMC10074478 DOI: 10.1021/acs.estlett.2c00902] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Revised: 01/03/2023] [Accepted: 01/04/2023] [Indexed: 06/19/2023]
Abstract
Studies on the destruction of solid per- and polyfluoroalkyl substances (PFAS) chemicals and PFAS-laden solid wastes significantly lag behind the urgent social demand. There is a great need to develop novel treatment processes that can destroy nonaqueous PFAS at ambient temperatures and pressures. In this study, we develop a piezoelectric-material-assisted ball milling (PZM-BM) process built on the principle that ball collisions during milling can activate PZMs to generate ∼kV potentials for PFAS destruction in the absence of solvents. Using boron nitride (BN), a typical PZM, as an example, we successfully demonstrate the complete destruction and near-quantitative (∼100%) defluorination of solid PFOS and perfluorooctanoic acid (PFOA) after a 2 h treatment. This process was also used to treat PFAS-contaminated sediment. Approximately 80% of 21 targeted PFAS were destroyed after 6 h of treatment. The reaction mechanisms were determined to be a combination of piezo-electrochemical oxidation of PFAS and fluorination of BN. The PZM-BM process demonstrates many potential advantages, as the degradation of diverse PFAS is independent of functional group and chain configurations and does not require caustic chemicals, heating, or pressurization. This pioneering study lays the groundwork for optimizing PZM-BM to treat various PFAS-laden solid wastes.
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Affiliation(s)
- Nanyang Yang
- Department
of Civil and Environmental Engineering, Clarkson University, Potsdam, New York13699, United States
| | - Shasha Yang
- Department
of Civil and Environmental Engineering, Clarkson University, Potsdam, New York13699, United States
- Institute
for a Sustainable Environment, Clarkson
University, Potsdam, New York13699, United States
| | - Qingquan Ma
- John
A. Reif, Jr. Department of Civil and Environmental Engineering, New Jersey Institute of Technology, Newark, New Jersey07102, United States
| | - Claudia Beltran
- Department
of Civil and Environmental Engineering, Clarkson University, Potsdam, New York13699, United States
| | - Yunqiao Guan
- Department
of Civil and Environmental Engineering, Clarkson University, Potsdam, New York13699, United States
| | - Madison Morsey
- Department
of Chemistry and Biomolecular Science, Clarkson
University, Potsdam, New York13699, United States
| | - Elizabeth Brown
- Department
of Civil and Environmental Engineering, Clarkson University, Potsdam, New York13699, United States
| | - Sujan Fernando
- Department
of Civil and Environmental Engineering, Clarkson University, Potsdam, New York13699, United States
| | - Thomas M. Holsen
- Department
of Civil and Environmental Engineering, Clarkson University, Potsdam, New York13699, United States
| | - Wen Zhang
- John
A. Reif, Jr. Department of Civil and Environmental Engineering, New Jersey Institute of Technology, Newark, New Jersey07102, United States
| | - Yang Yang
- Department
of Civil and Environmental Engineering, Clarkson University, Potsdam, New York13699, United States
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23
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Schaefer CE, Lavorgna GM, Lippincott DR, Nguyen D, Schaum A, Higgins CP, Field J. Leaching of Perfluoroalkyl Acids during Unsaturated Zone Flushing at a Field Site Impacted with Aqueous Film Forming Foam. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:1940-1948. [PMID: 36689630 DOI: 10.1021/acs.est.2c06903] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
While several studies have focused on perfluoroalkyl acid (PFAA) leaching from soils, field studies evaluating the relationship between PFAA mass removal and porewater concentrations as the PFAA source becomes depleted are lacking. Herein, in situ water flushing was performed at a site historically impacted with AFFF to accelerate the leaching of PFAAs from unsaturated soils in a highly characterized field test cell. Porous cup suction lysimeters were used to assess the changes in PFAA porewater concentrations as a function of PFAA mass removal from the unsaturated soils, where flushing was intermittently paused to determine ambient PFAA porewater concentrations. Results showed that the fractional decreases in PFAA porewater concentrations during flushing exceeded the fractional decrease in PFAA mass removal from the soil. PFOS porewater concentrations decrease by 76% (with negligible rebound) compared to only a 7.4% decrease in overall PFOS mass removed from the unsaturated zone. Overall, the results observed herein suggest that, when considering soil impacts to groundwater, less stringent soil cleanup criteria than those that consider an equivalent relationship between mass removal and mass discharge may be appropriate. In addition, remedial approaches that remove only a modest fraction of the PFAA soil mass may be protective of underlying groundwater, particularly for perfluorinated sulfonates with at least six carbons.
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Affiliation(s)
- Charles E Schaefer
- CDM Smith, 110 Fieldcrest Avenue, #8, 6th Floor, Edison, New Jersey08837, United States
| | - Graig M Lavorgna
- APTIM Federal Services, 17 Princess Rd, Lawrenceville, New Jersey08648, United States
| | - David R Lippincott
- APTIM Federal Services, 17 Princess Rd, Lawrenceville, New Jersey08648, United States
| | - Dung Nguyen
- CDM Smith, 14432 SE Eastgate Way, # 100, Bellevue, Washington98007, United States
| | - Andre Schaum
- Department of Molecular and Environmental Toxicology, Oregon State University, 1007 Agricultural and Life Science Building, Corvallis, Oregon97331, United States
| | - Christopher P Higgins
- Department of Civil and Environmental Engineering, Colorado School of Mines, Golden, Colorado80401, United States
| | - Jennifer Field
- Department of Molecular and Environmental Toxicology, Oregon State University, 1007 Agricultural and Life Science Building, Corvallis, Oregon97331, United States
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24
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Xing Y, Li Q, Chen X, Huang B, Ji L, Zhang Q, Fu X, Li T, Wang J. PFASs in Soil: How They Threaten Human Health through Multiple Pathways and Whether They Are Receiving Adequate Concern. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2023; 71:1259-1275. [PMID: 36622935 DOI: 10.1021/acs.jafc.2c06283] [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] [Indexed: 06/17/2023]
Abstract
Per- and polyfluoroalkyl substances (PFASs) have been mass-produced and widely applied in consumer and industrial products, resulting in their widespread presence in the environment. Features such as environmental persistence, bioaccumulation, and high toxicity even at low doses have made PFASs an increasing concern. This brief review focuses on soil PFASs, especially the effect of soil PFASs on other environmental media and their potential threats to human health through daily diet. Specifically, soil PFASs contamination caused by different pathways was first investigated. Soil pollution from application of aqueous film-forming foams (AFFFs) is generally more severe than that from fluorochemical manufacturing plants, followed by biosolid land use, landfill, and irrigation. Factors, such as carbon chain length of PFASs, wastewater treatment technology, geographical conditions, and regional development level, are related to soil PFASs' pollution. Then, the migration, bioaccumulation, and toxicity characteristics of soil PFASs were analyzed. Short-chain PFASs have higher solubility, mobility, and bioavailability, while long-chain PFASs have higher bioaccumulation potential and are more toxic to organisms. Factors such as soil texture, solution chemistry conditions, enzymes, and fertilization conditions also influence the environmental behavior of PFASs. The risk of human exposure to PFASs through agricultural and animal products is difficult to control and varies depending on living region, age, eating habits, lifestyle, ethnicity, etc. Soil PFASs threaten drinking water safety, affect soil function, and enter food webs, threatening human health. Knowledge gaps and perspectives in these research fields are also included in current work to assist future research to effectively investigate and understand the environmental risks of soil PFASs, thereby reducing human exposure.
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Affiliation(s)
- Yingna Xing
- Shandong Provincial Key Laboratory of Applied Microbiology, Ecology Institute, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250103, China
| | - Qi Li
- Shandong Provincial Key Laboratory of Applied Microbiology, Ecology Institute, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250103, China
| | - Xin Chen
- Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China
| | - Bin Huang
- Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China
| | - Lei Ji
- Shandong Provincial Key Laboratory of Applied Microbiology, Ecology Institute, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250103, China
| | - Qiang Zhang
- Shandong Provincial Key Laboratory of Applied Microbiology, Ecology Institute, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250103, China
| | - Xiaowen Fu
- Shandong Provincial Key Laboratory of Applied Microbiology, Ecology Institute, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250103, China
| | - Tianyuan Li
- Shandong Provincial Key Laboratory of Applied Microbiology, Ecology Institute, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250103, China
| | - Jianing Wang
- Shandong Provincial Key Laboratory of Applied Microbiology, Ecology Institute, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250103, China
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25
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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: 0] [Impact Index Per Article: 0] [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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26
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Anderson RH, Feild JB, Dieffenbach-Carle H, Elsharnouby O, Krebs RK. Assessment of PFAS in collocated soil and porewater samples at an AFFF-impacted source zone: Field-scale validation of suction lysimeters. CHEMOSPHERE 2022; 308:136247. [PMID: 36049637 DOI: 10.1016/j.chemosphere.2022.136247] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Revised: 08/23/2022] [Accepted: 08/25/2022] [Indexed: 06/15/2023]
Abstract
Per- and polyfluoroalkyl substances (PFAS) measurable in soil porewater authoritatively represent the mobile mass fraction critical to accurate assessment of leaching from source zones. This study evaluated PFAS occurrence in lysimeter-collected porewater samples for two depth intervals at a decades-old aqueous film-forming foam (AFFF)-impacted field site quarterly for a year. Notably, site-wide Log10 (∑PFAS) concentrations did not significantly differ among sampling events despite highly variable sample yields due to a heterogeneous and dynamic soil moisture regime. However, Log10 (∑PFAS) concentrations were significantly higher in the shallow interval concordant with higher mean soil concentrations and higher total organic carbon (TOC) reflecting net retention, which is supported by soil-to-groundwater annual mass discharge estimates less than 0.2% of the total source mass for any given PFAS. Interestingly, PFAS-specific Log10 (soil-to-porewater ratios) significantly increased with soil concentration in both depth intervals contrary to concentration dependence resulting from the saturation of sorption sites potentially implicating self-assembly as an additional operative retention mechanism. Overall, these data validate the use of suction lysimeters for short-term site characterization deployments and emphasize the importance of in situ porewater samples for interrogating PFAS transport within source zones.
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Affiliation(s)
| | - James B Feild
- Wood Environment & Infrastructure Solutions, Inc., Knoxville, TN, USA
| | | | - Omneya Elsharnouby
- Wood Environment & Infrastructure Solutions, Inc., Cambridge, Ontario, Canada
| | - Rita K Krebs
- Air Force Civil Engineer Center, Ellsworth AFB, SD, USA
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27
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Pritchard J, Hawkins KM, Cho YM, Spahr S, Struck SD, Higgins CP, Luthy RG. Black Carbon-Amended Engineered Media Filters for Improved Treatment of Stormwater Runoff. ACS ENVIRONMENTAL AU 2022; 3:34-46. [PMID: 36691657 PMCID: PMC9856624 DOI: 10.1021/acsenvironau.2c00037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 09/13/2022] [Accepted: 09/14/2022] [Indexed: 01/26/2023]
Abstract
Urban stormwater runoff is a significant driver of surface water quality impairment. Recently, attention has been drawn to potential beneficial use of urban stormwater runoff, including augmenting drinking water supply in water-stressed areas. However, beneficial use relies on improved treatment of stormwater runoff to remove mobile dissolved metals and trace organic contaminants (TrOCs). This study assesses six engineered media mixtures consisting of sand, zeolite, high-temperature gasification biochar, and regenerated activated carbon (RAC) for removing a suite of co-contaminants comprising five metals, three herbicides, four pesticides, a corrosion inhibitor, six per- and polyfluoroalkyl substances (PFASs), five polychlorinated biphenyls (PCBs), and six polycyclic aromatic hydrocarbons (PAHs). This long-term laboratory-scale column study uses a novel approach to generate reproducible synthetic stormwater that incorporates catch basin material and straw-derived dissolved organic carbon. Higher flow conditions (20 cm hr-1), larger sized media (0.42-1.68 mm), and downflow configuration with outlet control increase the relevance of this study to better enable implementation in the field. Biochar- and RAC-amended engineered media filters removed nearly all of the TrOCs in the effluent over the course of three months of continuous flow (480 empty bed volumes), while sample ports spaced at 25% and 50% along the column depth provide windows to observe contaminant transport. Biochar provided greater benefit to TrOC removal than RAC on a mass basis. This study used relatively high concentrations of contaminants and low biochar and RAC content to observe contaminant transport. Performance in the field is likely to be significantly better with higher biochar- and RAC-content filters and lower ambient stormwater contaminant concentrations. This study provides proof-of-concept for biochar- and RAC-amended engineered media filters operated at a flow rate of 20 cm hr-1 for removing dissolved TrOCs and metals and offers insights on the performance of biochar and RAC for improved stormwater treatment and field trials.
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Affiliation(s)
- James
Conrad Pritchard
- Re-inventing
the Nation’s Urban Water Infrastructure (ReNUWIt), National Science Foundation Engineering Research Center, Stanford, California 94305, United States,Department
of Civil & Environmental Engineering, Stanford University, Stanford, California 94305, United States
| | - Kathleen Mills Hawkins
- Re-inventing
the Nation’s Urban Water Infrastructure (ReNUWIt), National Science Foundation Engineering Research Center, Stanford, California 94305, United States,Department
of Civil & Environmental Engineering, Colorado School of Mines, Golden, Colorado 80401, United States
| | - Yeo-Myoung Cho
- Re-inventing
the Nation’s Urban Water Infrastructure (ReNUWIt), National Science Foundation Engineering Research Center, Stanford, California 94305, United States,Department
of Civil & Environmental Engineering, Stanford University, Stanford, California 94305, United States
| | - Stephanie Spahr
- Re-inventing
the Nation’s Urban Water Infrastructure (ReNUWIt), National Science Foundation Engineering Research Center, Stanford, California 94305, United States,Department
of Ecohydrology and Biogeochemistry, Leibniz
Institute of Freshwater Ecology and Inland Fisheries (IGB), 12587 Berlin, Germany
| | - Scott D. Struck
- Geosyntec
Consultants, Los Angeles, California 90015, United States
| | - Christopher P. Higgins
- Re-inventing
the Nation’s Urban Water Infrastructure (ReNUWIt), National Science Foundation Engineering Research Center, Stanford, California 94305, United States,Department
of Civil & Environmental Engineering, Colorado School of Mines, Golden, Colorado 80401, United States
| | - Richard G. Luthy
- Re-inventing
the Nation’s Urban Water Infrastructure (ReNUWIt), National Science Foundation Engineering Research Center, Stanford, California 94305, United States,Department
of Civil & Environmental Engineering, Stanford University, Stanford, California 94305, United States,
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28
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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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29
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Liu X, Chen L, Yu L, Hua Z, Zhang Y, Ma Y, Lu Y, Dong Y, Wang Y, Zhang Z, Xue H. Removing nutrients from wastewater by constructed wetlands under perfluoroalkyl acids stress. ENVIRONMENTAL RESEARCH 2022; 212:113334. [PMID: 35452673 DOI: 10.1016/j.envres.2022.113334] [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: 01/01/2022] [Revised: 03/20/2022] [Accepted: 04/15/2022] [Indexed: 06/14/2023]
Abstract
Constructed wetlands (CWs) are often used to treat wastewater discharged from wastewater treatment plants (WWTPs), while emerging contaminants (such as perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS)) have been commonly discovered in WWTPs. However, no research has examined whether PFOA/OS (i.e. PFOA and PFOS) affects the performance of CW. Therefore, this study compared the nutrient removal efficiencies of four CWs with varied configurations under PFOA/OS and no PFOA/OS stress conditions. We found that CW containing plants or/and iron-carbon had higher removal efficiency for nutrients (except NH4+-N) than conventional CW in stable operation under wastewater without PFOA/OS. Plants or/and iron increased the nutrient removal efficiency by plant uptake, chemical reaction, and co-precipitation of iron hydroxides. In contrast, the iron-carbon inhibited the nitrification of nitrifying bacteria by consuming dissolved oxygen, converting NO3--N to NH4+-N. Although the removal efficiencies of nutrients by CWs differed after introducing PFOA/OS, the removal order was consistent with those before adding PFOA/OS. Plants or/and iron-carbon effectively increased CWs' resistance to PFOA/OS loading and toxicity, and the function of iron-carbon was superior to the plants. In addition, PFOA/OS reduced the abundances of microbes Hydrogenophaga, Pseudomonas, Sphingomonas, Nitrospira, and Candidatus_Accumulibacter that contributed to nutrient removal.
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Affiliation(s)
- Xiaodong Liu
- Ministry of Education Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, College of Environment, Hohai Universities, Nanjing, 210098, China
| | - Luying Chen
- Longteng Engineering Design CO., LTD., Jiangsu, 210014, China
| | - Liang Yu
- Ministry of Education Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, College of Environment, Hohai Universities, Nanjing, 210098, China; Yangtze Institute for Conservation and Development, Hohai University, Jiangsu, 210098, China.
| | - Zulin Hua
- Ministry of Education Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, College of Environment, Hohai Universities, Nanjing, 210098, China; Yangtze Institute for Conservation and Development, Hohai University, Jiangsu, 210098, China
| | - Yuan Zhang
- Ministry of Education Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, College of Environment, Hohai Universities, Nanjing, 210098, China; Yangtze Institute for Conservation and Development, Hohai University, Jiangsu, 210098, China
| | - Yixin Ma
- Ministry of Education Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, College of Environment, Hohai Universities, Nanjing, 210098, China; Yangtze Institute for Conservation and Development, Hohai University, Jiangsu, 210098, China
| | - Ying Lu
- Ministry of Education Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, College of Environment, Hohai Universities, Nanjing, 210098, China; Yangtze Institute for Conservation and Development, Hohai University, Jiangsu, 210098, China
| | - Yueyang Dong
- Ministry of Education Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, College of Environment, Hohai Universities, Nanjing, 210098, China; Yangtze Institute for Conservation and Development, Hohai University, Jiangsu, 210098, China
| | - Yifan Wang
- Ministry of Education Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, College of Environment, Hohai Universities, Nanjing, 210098, China; Yangtze Institute for Conservation and Development, Hohai University, Jiangsu, 210098, China
| | - Zihao Zhang
- Ministry of Education Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, College of Environment, Hohai Universities, Nanjing, 210098, China; Yangtze Institute for Conservation and Development, Hohai University, Jiangsu, 210098, China
| | - Hongqin Xue
- School of Civil Engineering, Nanjing Forestry University, Nanjing, 210037, China
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30
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Nguyen TMH, Bräunig J, Kookana RS, Kaserzon SL, Knight ER, Vo HNP, Kabiri S, Navarro DA, Grimison C, Riddell N, Higgins CP, McLaughlin MJ, Mueller JF. Assessment of Mobilization Potential of Per- and Polyfluoroalkyl Substances for Soil Remediation. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:10030-10041. [PMID: 35763608 DOI: 10.1021/acs.est.2c00401] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
This study investigated the mobilization of a wide range of per- and polyfluoroalkyl substances (PFASs) present in aqueous film-forming foams (AFFFs) in water-saturated soils through one-dimensional (1-D) column experiments with a view to assessing the feasibility of their remediation by soil desorption and washing. Results indicated that sorption/desorption of most of the shorter-carbon-chain PFASs (C ≤ 6) in soil reached greater than 99% rapidly─after approximately two pore volumes (PVs) and were well predicted by an equilibrium transport model, indicating that they will be readily removed by soil washing technologies. In contrast, the equilibrium model failed to predict the mobilization of longer-chain PFASs (C ≥ 7), indicating the presence of nonequilibrium sorption/desorption (confirmed by a flow interruption experiment). The actual time taken to attain 99% sorption/desorption was up to 5 times longer than predicted by the equilibrium model (e.g., ∼62 PVs versus ∼12 PVs predicted for perfluorooctane sulfonate (PFOS) in loamy sand). The increasing contribution of hydrophobic interactions over the electrostatic interactions is suggested as the main driving factor of the nonequilibrium processes. The inverse linear relationship (R2 = 0.6, p < 0.0001) between the nonequilibrium mass transfer rate coefficient and the Freundlich sorption coefficient could potentially be a useful means for preliminary evaluation of potential nonequilibrium sorption/desorption of PFASs in soils.
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Affiliation(s)
- Thi Minh Hong Nguyen
- QAEHS, Queensland Alliance for Environmental Health Sciences, The University of Queensland, Brisbane, QLD 4102, Australia
| | - Jennifer Bräunig
- QAEHS, Queensland Alliance for Environmental Health Sciences, The University of Queensland, Brisbane, QLD 4102, Australia
| | - Rai S Kookana
- CSIRO, The Commonwealth Scientific and Industrial Research Organisation Land and Water, PMB 2, Glen Osmond, SA 5064, Australia
- School of Agriculture, Food and Wine, The University of Adelaide, Waite Campus, PMB 1, Glen Osmond, SA 5064, Australia
| | - Sarit L Kaserzon
- QAEHS, Queensland Alliance for Environmental Health Sciences, The University of Queensland, Brisbane, QLD 4102, Australia
| | - Emma R Knight
- QAEHS, Queensland Alliance for Environmental Health Sciences, The University of Queensland, Brisbane, QLD 4102, Australia
| | - Hoang Nhat Phong Vo
- QAEHS, Queensland Alliance for Environmental Health Sciences, The University of Queensland, Brisbane, QLD 4102, Australia
| | - Shervin Kabiri
- School of Agriculture, Food and Wine, The University of Adelaide, Waite Campus, PMB 1, Glen Osmond, SA 5064, Australia
| | - Divina A Navarro
- CSIRO, The Commonwealth Scientific and Industrial Research Organisation Land and Water, PMB 2, Glen Osmond, SA 5064, Australia
- School of Agriculture, Food and Wine, The University of Adelaide, Waite Campus, PMB 1, Glen Osmond, SA 5064, Australia
| | | | - Nicole Riddell
- Wellington Laboratories Inc., 345 Southgate Drive, Guelph, Ontario N1G 3M5, Canada
| | - Christopher P Higgins
- QAEHS, Queensland Alliance for Environmental Health Sciences, The University of Queensland, Brisbane, QLD 4102, Australia
- Department of Civil and Environmental Engineering, Colorado School of Mines, Golden, Colorado 80401, United States
| | - Michael J McLaughlin
- School of Agriculture, Food and Wine, The University of Adelaide, Waite Campus, PMB 1, Glen Osmond, SA 5064, Australia
| | - Jochen F Mueller
- QAEHS, Queensland Alliance for Environmental Health Sciences, The University of Queensland, Brisbane, QLD 4102, Australia
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31
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Charbonnet J, McDonough CA, Xiao F, Schwichtenberg T, Cao D, Kaserzon S, Thomas KV, Dewapriya P, Place BJ, Schymanski EL, Field JA, Helbling DE, Higgins CP. Communicating Confidence of Per- and Polyfluoroalkyl Substance Identification via High-Resolution Mass Spectrometry. ENVIRONMENTAL SCIENCE & TECHNOLOGY LETTERS 2022; 9:473-481. [PMID: 35719859 PMCID: PMC9202347 DOI: 10.1021/acs.estlett.2c00206] [Citation(s) in RCA: 52] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Revised: 05/19/2022] [Accepted: 05/19/2022] [Indexed: 05/19/2023]
Abstract
Per- and polyfluoroalkyl substances (PFASs) are important environmental contaminants, yet relatively few analytical reference standards exist for this class. Nontarget analyses performed by means of high-resolution mass spectrometry (HRMS) are increasingly common for the discovery and identification of PFASs in environmental and biological samples. The certainty of PFAS identifications made via HRMS must be communicated through a reliable and harmonized approach. Here, we present a confidence scale along with identification criteria specific to suspect or nontarget analysis of PFASs by means of nontarget HRMS. Confidence levels range from level 1a-"Confirmed by Reference Standard," and level 1b-"Indistinguishable from Reference Standard," to level 5-"Exact Masses of Interest," which are identified by suspect screening or data filtering, two common forms of feature prioritization. This confidence scale is consistent with general criteria for communicating confidence in the identification of small organic molecules by HRMS (e.g., through a match to analytical reference standards, library MS/MS, and/or retention times) but incorporates the specific conventions and tools used in PFAS classification and analysis (e.g., detection of homologous series and specific ranges of mass defects). Our scale clarifies the level of certainty in PFAS identification and, in doing so, facilitates more efficient identification.
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Affiliation(s)
- Joseph
A. Charbonnet
- Department
of Civil and Environmental Engineering, Colorado School of Mines, Golden, Colorado 80401, United States
- Department
of Civil, Construction and Environmental Engineering, Iowa State University, Ames, Iowa 50011, United States
| | - Carrie A. McDonough
- Department
of Civil Engineering, Stony Brook University, Stony Brook, New York 11794, United States
| | - Feng Xiao
- Department
of Civil Engineering, University of North
Dakota, Grand
Forks, North Dakota 58202, United States
| | - Trever Schwichtenberg
- Department
of Chemistry, Oregon State University, Corvallis, Oregon 97331, United States
| | - Dunping Cao
- Department
of Chemistry, Oregon State University, Corvallis, Oregon 97331, United States
| | - Sarit Kaserzon
- Queensland
Alliance for Environmental Health Sciences (QAEHS), The University of Queensland, Woolloongabba, QLD 4102, Australia
| | - Kevin V. Thomas
- Queensland
Alliance for Environmental Health Sciences (QAEHS), The University of Queensland, Woolloongabba, QLD 4102, Australia
| | - Pradeep Dewapriya
- Queensland
Alliance for Environmental Health Sciences (QAEHS), The University of Queensland, Woolloongabba, QLD 4102, Australia
| | - Benjamin J. Place
- National
Institute of Standards and Technology, Gaithersburg, Maryland 20899, United States
| | - Emma L. Schymanski
- Luxembourg
Centre for Systems Biomedicine (LCSB), University
of Luxembourg, Belvaux 4362, Luxembourg
| | - Jennifer A. Field
- Department
of Environmental and Molecular Toxicology, Oregon State University, Corvallis, Oregon 97331, United States
| | - Damian E. Helbling
- School
of Civil and Environmental Engineering, Cornell University, Ithaca, New York 14850, United States
| | - Christopher P. Higgins
- Department
of Civil and Environmental Engineering, Colorado School of Mines, Golden, Colorado 80401, United States
- Queensland
Alliance for Environmental Health Sciences (QAEHS), The University of Queensland, Woolloongabba, QLD 4102, Australia
- Phone: 720-984-2116.
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32
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McDonough CA, Li W, Bischel HN, De Silva AO, DeWitt JC. Widening the Lens on PFASs: Direct Human Exposure to Perfluoroalkyl Acid Precursors (pre-PFAAs). ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:6004-6013. [PMID: 35324171 PMCID: PMC10782884 DOI: 10.1021/acs.est.2c00254] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Determining health risks associated with per-/polyfluoroalkyl substances (PFASs) is a highly complex problem requiring massive efforts for scientists, risk assessors, and regulators. Among the most poorly understood pressing questions is the relative importance of pre-PFAAs, which are PFASs that degrade to highly persistent perfluoroalkyl acids. How many of the vast number of existing pre-PFAAs are relevant for direct human exposure, and what are the predominant exposure pathways? What evidence of direct exposure to pre-PFAAs is provided by human biomonitoring studies? How important are pre-PFAAs and their biotransformation products for human health risk assessment? This article outlines recent progress and recommendations toward widening the lens on human PFAS exposure to include the pre-PFAA subclass.
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Affiliation(s)
- Carrie A. McDonough
- Department of Civil Engineering, Stony Brook University, Stony Brook, NY 11794, USA
| | - Wenting Li
- Department of Civil & Environmental Engineering, University of California Davis, Davis, CA 95616 USA
| | - Heather N. Bischel
- Department of Civil & Environmental Engineering, University of California Davis, Davis, CA 95616 USA
| | - Amila O. De Silva
- Aquatic Contaminants Research Division, Water Science Technology Directorate, Environment and Climate Change Canada, Burlington, Ontario L7S 1A1, Canada
| | - Jamie C. DeWitt
- Department of Pharmacology & Toxicology, Brody School of Medicine, East Carolina University, Greenville, NC 27834, USA
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33
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Kholofelo Selahle S, Mpupa A, Nosizo Nomngongo P. Liquid chromatographic determination of per- and polyfluoroalkyl substances in environmental river water samples. ARAB J CHEM 2022. [DOI: 10.1016/j.arabjc.2022.103960] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
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34
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Kabiri S, Tucker W, Navarro DA, Bräunig J, Thompson K, Knight ER, Nguyen TMH, Grimison C, Barnes CM, Higgins CP, Mueller JF, Kookana RS, McLaughlin MJ. Comparing the Leaching Behavior of Per- and Polyfluoroalkyl Substances from Contaminated Soils Using Static and Column Leaching Tests. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:368-378. [PMID: 34932318 DOI: 10.1021/acs.est.1c06604] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Soil contaminated with aqueous film-forming foams (AFFFs) containing per- and polyfluoroalkyl substances (PFASs) at firefighting training sites has become a major concern worldwide. To date, most studies have focused on assessing soil-water partitioning behavior of PFASs and the key factors that can affect their sorption, whereas PFASs leaching from contaminated soils have not yet been widely investigated. This study evaluated the leaching and desorption of a wide range of PFASs from twelve contaminated soils using the Australian Standard Leaching Procedure (ASLP), the U.S. EPA Multiple Extraction Procedure (MEP), and Leaching Environmental Assessment Framework (LEAF). All three leaching tests provided a similar assessment of PFAS leaching behavior. Leaching of PFASs from soils was related to C-chain lengths and their functional head groups. While short-chain (CF2 ≤ 6) PFASs were easily desorbed and leached, long-chain PFASs were more difficult to desorb. PFASs with a carboxylate head group were leached more readily and to a greater extent than those with a sulfonate or sulfonamide head group. Leaching of long-chain PFASs was pH-dependent where leaching increased at high pH, while leaching of short-chain PFASs was less sensitive to pH. Comparing different leaching tests showed that the results using the alkaline ASLP were similar to the cumulative MEP data and the former might be more practical for routine use than the MEP. No single soil property was adequately able to describe PFAS leaching from the soils. Overall, the PFAS chemical structure appeared to have a greater effect on PFAS leaching from soil than soil physicochemical properties.
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Affiliation(s)
- Shervin Kabiri
- School of Agriculture, Food and Wine, The University of Adelaide, Waite Campus, PMB1, Glen Osmond, South Australia 5064, Australia
| | - William Tucker
- School of Agriculture, Food and Wine, The University of Adelaide, Waite Campus, PMB1, Glen Osmond, South Australia 5064, Australia
| | - Divina A Navarro
- CSIRO Land and Water, PMB 2, Glen Osmond, South Australia 5064, Australia
| | - Jennifer Bräunig
- Queensland Alliance for Environmental Health Sciences (QAEHS), The University of Queensland, Brisbane, Queensland 4102, Australia
| | - Kristie Thompson
- Queensland Alliance for Environmental Health Sciences (QAEHS), The University of Queensland, Brisbane, Queensland 4102, Australia
| | - Emma R Knight
- Queensland Alliance for Environmental Health Sciences (QAEHS), The University of Queensland, Brisbane, Queensland 4102, Australia
| | - Thi Minh Hong Nguyen
- Queensland Alliance for Environmental Health Sciences (QAEHS), The University of Queensland, Brisbane, Queensland 4102, Australia
| | | | - Craig M Barnes
- Airservices Australia, 25 Constitution Avenue, Canberra, Australian Capital Territory 2601, Australia
| | - Christopher P Higgins
- Department of Civil and Environmental Engineering, Colorado School of Mines, Golden, Colorado 80401, United States
| | - Jochen F Mueller
- Queensland Alliance for Environmental Health Sciences (QAEHS), The University of Queensland, Brisbane, Queensland 4102, Australia
| | - Rai S Kookana
- CSIRO Land and Water, PMB 2, Glen Osmond, South Australia 5064, Australia
| | - Michael J McLaughlin
- School of Agriculture, Food and Wine, The University of Adelaide, Waite Campus, PMB1, Glen Osmond, South Australia 5064, Australia
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35
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Nickerson A, Maizel AC, Olivares CI, Schaefer CE, Higgins CP. Simulating Impacts of Biosparging on Release and Transformation of Poly- and Perfluorinated Alkyl Substances from Aqueous Film-Forming Foam-Impacted Soil. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:15744-15753. [PMID: 34748313 DOI: 10.1021/acs.est.1c03448] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Poly- and perfluorinated alkyl substances (PFASs) frequently co-occur with fuel-derived contaminants because of the use of aqueous film-forming foam (AFFF). Biosparging is a common remediation technology that injects oxygen into the saturated zone to encourage aerobic biodegradation, thereby altering aquifer redox conditions and potentially facilitating the biotransformation of polyfluorinated substances. Between 136 and 280 pore volumes of nitrogen-sparged or oxygen-sparged artificial groundwater amended with toluene were pumped through four saturated, AFFF-impacted soil columns to assess impacts on PFAS release and transformation. Column effluents and soils were analyzed for PFASs by high-resolution mass spectrometry. Significantly higher concentrations of five PFASs eluted from O2-sparged columns compared to N2-sparged columns shortly after sparging was initiated. The mass fractions eluted of many zwitterionic, sulfonamide-based PFASs were higher in both sets of columns than unaltered, non-biostimulated columns. Mass balance calculations suggested the transformation of sulfonamide-based precursors to perfluorinated sulfonamides (i.e., perfluorohexanesulfonamide) in oxygen- and nitrogen-sparged columns: recoveries of perfluorinated sulfonamides were 158-235% for C3-C6 homologs but recoveries of several prominent sulfonamide-based zwitterions were low. For example, the recovery of n-carboxyethyldimethyl-ammoniopropyl perfluorohexanesulfonamide was 9-13%. These results suggest biosparging can enhance the transformation and release of PFASs in saturated soils, which has important implications for site characterization and remediation.
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Affiliation(s)
- Anastasia Nickerson
- Department of Civil and Environmental Engineering, Colorado School of Mines, 1500 Illinois St, Golden, Colorado 80401, United States
| | - Andrew C Maizel
- Department of Civil and Environmental Engineering, Colorado School of Mines, 1500 Illinois St, Golden, Colorado 80401, United States
| | - Christopher I Olivares
- Department of Civil and Environmental Engineering, University of California Berkeley, Berkeley, California 94720, United States
| | | | - Christopher P Higgins
- Department of Civil and Environmental Engineering, Colorado School of Mines, 1500 Illinois St, Golden, Colorado 80401, United States
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