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Usman M, Chaudhary A, Hanna K. Efficient PFAS removal from contaminated soils through combined washing and adsorption in soil effluents. JOURNAL OF HAZARDOUS MATERIALS 2024; 476:135118. [PMID: 38981229 DOI: 10.1016/j.jhazmat.2024.135118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2024] [Revised: 06/01/2024] [Accepted: 07/04/2024] [Indexed: 07/11/2024]
Abstract
This study investigates soil washing as a viable strategy to remove poly- and perfluoroalkyl substances (PFAS) from contaminated soils using various washing agents including water, methanol, ethanol, and cyclodextrin ((2-Hydroxypropyl)-β-cyclodextrin HPCD)). Water was less effective (removing only 30 % of PFAS), especially for long-chain hydrophobic PFAS. Methanol (50 % v/v) or HPCD (10 mg g-1 soil) achieved > 95 % PFAS removal regardless of PFAS type, soil size fraction (0-400 µm or 400-800 µm), or experimental setups (batch or column, at liquid/solid (L/S) = 1). Column optimization studies revealed improved efficiency at L/S = 10 with diluted washing solutions, where HPCD exhibited rapid PFAS mobilization even at lower concentrations (1 mg mL-1). We then applied a first-order decay model to effectively predict PFAS breakthrough curves and mobilization within soil columns. Subsequent treatment of wash effluents by activated carbon and biochar effectively reduced PFAS concentrations below detection limits. The performance of both soil washing and subsequent adsorption was found to depend strongly on the specific characteristics of PFAS compounds. These findings highlight the significant potential of methanol and HPCD in soil washing and the effectiveness of integrated soil washing and adsorption for optimizing PFAS removal.
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Affiliation(s)
- Muhammad Usman
- Université de Rennes, Ecole Nationale Supérieure de Chimie de Rennes, CNRS, ISCR-UMR 6226, F-35000 Rennes, France.
| | - Aaifa Chaudhary
- Université de Rennes, Ecole Nationale Supérieure de Chimie de Rennes, CNRS, ISCR-UMR 6226, F-35000 Rennes, France; Environmental Mineralogy & Chemistry, Center for Applied Geosciences, University of Tübingen, 72074 Tübingen, Germany
| | - Khalil Hanna
- Université de Rennes, Ecole Nationale Supérieure de Chimie de Rennes, CNRS, ISCR-UMR 6226, F-35000 Rennes, France.
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2
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Peter L, Modiri-Gharehveran M, Alvarez-Campos O, Evanylo GK, Lee LS. PFAS fate using lysimeters during degraded soil reclamation using biosolids. JOURNAL OF ENVIRONMENTAL QUALITY 2024. [PMID: 38816342 DOI: 10.1002/jeq2.20576] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Accepted: 05/01/2024] [Indexed: 06/01/2024]
Abstract
Carbon- and nutrient-rich biosolids are used in agriculture and land reclamation. However, per- and polyfluoroalkyl substances (PFAS) typically present in biosolids raise concerns of PFAS leaching to groundwater and plant uptake. Here, we investigated PFAS persistence and leaching from biosolids applied to a site constructed artificially to mimic degraded soils. Treatments included biosolids and biosolids blended with mulch applied at different rates to attain either one and five times the agronomic N rate for vegetable crops and a control treatment with synthetic urea and triple superphosphate fertilizer. Leachates were collected for a 2-year period from 15-cm depth zero-tension drainage lysimeters. Soils were analyzed post biosolids application. PFAS were quantified using isotope-dilution, solid-phase extraction and liquid chromatography tandem mass spectrometry. Leachate profiles exemplified an initial high total PFAS concentration, followed by a sharp decline and subsequent small fluctuations attributed to pre-existing soil conditions and rainfall patterns. Quantifiable PFAS in leachate were proportional to biosolids application rates. Short-chain perfluoroalkyl acids (CF2 < 6) were dominant in leachate, while the percentage of longer chains homologues was higher in soils. A 43% biosolids blend with mulch resulted in 21% lower PFAS leachate concentrations even with the blend application rate being 1.5 times higher than biosolids due to the blend's lower N-content. The blending effect was more pronounced for long-chain perfluoroalkyl sulfonic acids that have a greater retention by soils and the air-water interface. Biosolids blending as a pragmatic strategy for reducing PFAS leachate concentrations may aid in the sustainable beneficial reuse of biosolids.
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Affiliation(s)
- Lynda Peter
- Department of Agronomy, Ecological Sciences & Engineering Interdisciplinary Graduate Program, Purdue University, West Lafayette, Indiana, USA
| | - Mahsa Modiri-Gharehveran
- Environmental & Ecological Engineering, Purdue University, West Lafayette, Indiana, USA
- EA Engineering, Science, and Technology, Inc., PBC, Hunt Valley, Maryland, USA
| | - Odiney Alvarez-Campos
- USAID, Washington, District of Columbia, USA
- School of Plant and Environmental Sciences, Virginia Tech, Blacksburg, Virginia, USA
| | - Gregory K Evanylo
- School of Plant and Environmental Sciences, Virginia Tech, Blacksburg, Virginia, USA
| | - Linda S Lee
- Department of Agronomy, Ecological Sciences & Engineering Interdisciplinary Graduate Program, Purdue University, West Lafayette, Indiana, USA
- Environmental & Ecological Engineering, Purdue University, West Lafayette, Indiana, USA
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3
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Feng G, Zhou B, Yuan R, Luo S, Gai N, Chen H. Influence of soil composition and environmental factors on the adsorption of per- and polyfluoroalkyl substances: A review. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 925:171785. [PMID: 38508244 DOI: 10.1016/j.scitotenv.2024.171785] [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: 02/02/2024] [Revised: 03/09/2024] [Accepted: 03/15/2024] [Indexed: 03/22/2024]
Abstract
Per- and polyfluoroalkyl substances (PFASs) have garnered considerable scientific and regulatory scrutiny due to their widespread distribution across environments and their potential toxicological impacts on human health. The pedosphere serves as a vital reservoir for these chemicals, significantly determining their environmental trajectory and chemical transformations. This study offers a comprehensive synthesis of the current understanding regarding the adsorption mechanics of PFASs in soil matrices. Due to their unique molecular structure, PFASs predominantly engage in hydrophobic and electrostatic interactions during soil adsorption. This work thoroughly evaluates the influence of various factors on adsorption efficiency, including soil properties, molecular characteristics of PFASs, and the prevailing environmental conditions. The complex nature of soil environments complicates isolating individual impacts on PFAS behavior, necessitating an integrated approach to understanding their environmental destinies better. Through this exploration, we seek to clarify the complex interplay of factors that modulate the adsorption of PFASs in soils, highlighting the urgent need for future research to disentangle the intricate and combined effects that control the environmental behavior of PFAS compounds.
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Affiliation(s)
- Ge Feng
- Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China; Key Laboratory of Eco-geochemistry, Ministry of Natural Resources of China, National Research Center for Geo-analysis (NRCGA), Beijing 100037, China
| | - Beihai Zhou
- Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China
| | - Rongfang Yuan
- Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China
| | - Shuai Luo
- Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China
| | - Nan Gai
- Key Laboratory of Eco-geochemistry, Ministry of Natural Resources of China, National Research Center for Geo-analysis (NRCGA), Beijing 100037, China.
| | - Huilun Chen
- Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China.
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Cai W, Navarro DA, Du J, Srivastava P, Cao Z, Ying G, Kookana RS. Effect of heavy metal co-contaminants on the sorption of thirteen anionic per- and poly-fluoroalkyl substances (PFAS) in soils. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 905:167188. [PMID: 37734606 DOI: 10.1016/j.scitotenv.2023.167188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2023] [Revised: 09/13/2023] [Accepted: 09/16/2023] [Indexed: 09/23/2023]
Abstract
Understanding the sorption behavior of per- and poly-fluoroalkyl substances (PFAS) in soils are essential for assessing their mobility and risk in the environment. Heavy metals often coexist with PFAS depending on the source and history of contamination. In this study, we investigated the effect of heavy metal co-contaminants (Pb2+, Cu2+ and Zn2+) on the sorption of 13 anionic PFAS with different perfluorocarbon chain length (C3-C9) in two soils with different properties. Results revealed that Pb2+, Cu2+ and Zn2+ had little effect on the sorption of most short-chain compounds, while the presence of these heavy metals enhanced the sorption of long-chain PFAS in two soils. The distribution coefficients (Kd) of several long-chain PFAS linearly increased with increasing concentrations of heavy metal, especially in the presence of Pb2+ (ΔKd/Δ [Pb2+] > 3 for PFOS and PFNA vs <1 for PFPeS and PFHxS). While several mechanisms may have contributed to the enhancement of sorption of PFAS, the heavy metals most likely contributed through enhanced hydrophobic interactions of PFAS by neutralizing the negative charge of adsorption surfaces in soils and thus making it more favorable for their partitioning onto the solid phase. Moreover, the increase in the concentrations of heavy metals led to a decrease in the pH of the system and promoted sorption of long-chain compounds, especially in soil with lower organic carbon content. Overall, this study provides evidence that the presence of co-existing heavy metal cations in soils can significantly enhance the sorption of long-chain PFAS onto soil, thereby potentially limiting their mobility in the environment.
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Affiliation(s)
- Wenwen Cai
- School of Environment, Key Laboratory for Yellow River and Huai River Water Environment and Pollution Control, Ministry of Education, Henan Key Laboratory for Environmental Pollution Control, International Joint Laboratory on Key Techniques in Water Treatment, Henan Normal University, Xinxiang 453007, China; State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Divina A Navarro
- CSIRO Environment, Locked Bag 2, Glen Osmond, 5064, Australia; School of Agriculture, Food and Wine, The University of Adelaide, Waite Campus, Locked Bag 1, Glen Osmond 5064, Australia.
| | - Jun Du
- CSIRO Environment, Locked Bag 2, Glen Osmond, 5064, Australia
| | | | - Zhiguo Cao
- School of Environment, Key Laboratory for Yellow River and Huai River Water Environment and Pollution Control, Ministry of Education, Henan Key Laboratory for Environmental Pollution Control, International Joint Laboratory on Key Techniques in Water Treatment, Henan Normal University, Xinxiang 453007, China
| | - Guangguo Ying
- School of Environment, South China Normal University, Guangzhou 510006, China
| | - Rai S Kookana
- CSIRO Environment, Locked Bag 2, Glen Osmond, 5064, Australia; School of Agriculture, Food and Wine, The University of Adelaide, Waite Campus, Locked Bag 1, Glen Osmond 5064, Australia
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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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Ganbat N, Hamdi FM, Ibrar I, Altaee A, Alsaka L, Samal AK, Zhou J, Hawari AH. Iron slag permeable reactive barrier for PFOA removal by the electrokinetic process. JOURNAL OF HAZARDOUS MATERIALS 2023; 460:132360. [PMID: 37657326 DOI: 10.1016/j.jhazmat.2023.132360] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Revised: 08/14/2023] [Accepted: 08/20/2023] [Indexed: 09/03/2023]
Abstract
The efficacy of the Standalone Electrokinetic (EK) process in soil PFAS removal is negligible, primarily due to the intersecting mechanisms of electromigration and electroosmosis transportation. Consequently, the redistribution of PFAS across the soil matrix occurs, hampering effective remediation efforts. Permeable reactive barrier (PRB) has been used to capture contaminants and extract them at the end of the EK process. This study conducted laboratory-scale tests to evaluate the feasibility of the iron slag PRB enhanced-EK process in conjunction with Sodium Cholate (NaC) biosurfactant as a cost-effective and sustainable method for removing PFOA from the soil. A 2 cm iron slag-based PRB with a pH of 9.5, obtained from the steel-making industry, was strategically embedded in the middle of the EK reactors to capture PFOA within the soil. The main component of the slag, iron oxide, exhibited significant adsorption capacity for PFOA contamination. The laboratory-scale tests were conducted over two weeks, revealing a PFOA removal rate of more than 79% in the slag/activated carbon PRB-EK test with NaC enhancement and 70% PFOA removal in the slag/activated carbon PRB-EK without NaC. By extending the duration of the slag/AC PRB-EK test with NaC enhancement to three weeks, the PFOA removal rate increased to 94.09%, with the slag/AC PRB capturing over 87% of the initial PFOA concentration of 10 mg/L. The specific energy required for soil decontamination by the EK process was determined to be 0.15 kWh/kg. The outcomes of this study confirm the feasibility of utilizing iron slag waste in the EK process to capture PFOA contaminants, offering a sustainable approach to soil decontamination. Combining iron slag PRB and NaC biosurfactant provides a cost-effective and environmentally friendly method for efficient PFOA removal from soil.
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Affiliation(s)
- Namuun Ganbat
- Centre for Green Technology, School of Civil and Environmental Engineering, University of Technology Sydney, Australia
| | - Faris M Hamdi
- Centre for Green Technology, School of Civil and Environmental Engineering, University of Technology Sydney, Australia
| | - Ibrar Ibrar
- Centre for Green Technology, School of Civil and Environmental Engineering, University of Technology Sydney, Australia
| | - Ali Altaee
- Centre for Green Technology, School of Civil and Environmental Engineering, University of Technology Sydney, Australia.
| | - Lilyan Alsaka
- Centre for Green Technology, School of Civil and Environmental Engineering, University of Technology Sydney, Australia
| | - Akshaya K Samal
- Centre for Nano and Material Sciences, Jain University, Ramanagara, Bangalore 562 112, Karnataka, India
| | - John Zhou
- Centre for Green Technology, School of Civil and Environmental Engineering, University of Technology Sydney, Australia
| | - Alaa H Hawari
- Department of Civil and Architectural Engineering, College of Engineering, Qatar University, PO Box 2713, Doha, Qatar
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7
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Huang YR, Liu SS, Zi JX, Cheng SM, Li J, Ying GG, Chen CE. In Situ Insight into the Availability and Desorption Kinetics of Per- and Polyfluoroalkyl Substances in Soils with Diffusive Gradients in Thin Films. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:7809-7817. [PMID: 37155686 DOI: 10.1021/acs.est.2c09348] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
The physicochemical exchange dynamics between the solid and solution phases of per- and polyfluoroalkyl substances (PFAS) in soils needs to be better understood. This study employed an in situ tool, diffusive gradients in thin films (DGT), to understand the distribution and exchange kinetics of five typical PFAS in four soils. Results show a nonlinear relationship between the PFAS masses in DGT and time, implying that PFAS were partially supplied by the solid phase in all of the soils. A dynamic model DGT-induced fluxes in soils/sediments (DIFS) was used to interpret the results and derive the distribution coefficients for the labile fraction (Kdl), response time (tc), and adsorption/desorption rates (k1 and k-1). The larger labile pool size (indicated by Kdl) for the longer chain PFAS implies their higher potential availability. The shorter chain PFAS tend to have a larger tc and relatively smaller k-1, implying that the release of these PFAS in soils might be kinetically limited but not for more hydrophobic compounds, such as perfluorooctanesulfonic acid (PFOS), although soil properties might play an important role. Kdl ultimately controls the PFAS availability in soils, while the PFAS release from soils might be kinetically constrained (which may also hold for biota uptake), particularly for more hydrophilic PFAS.
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Affiliation(s)
- Yue-Rui Huang
- Environmental Research Institute/School of Environment, Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety & MOE Key Laboratory of Theoretical Chemistry of Environment, South China Normal University, Guangzhou, Guangdong 510006, People's Republic of China
| | - Si-Si Liu
- Environmental Research Institute/School of Environment, Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety & MOE Key Laboratory of Theoretical Chemistry of Environment, South China Normal University, Guangzhou, Guangdong 510006, People's Republic of China
| | - Jin-Xin Zi
- Environmental Research Institute/School of Environment, Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety & MOE Key Laboratory of Theoretical Chemistry of Environment, South China Normal University, Guangzhou, Guangdong 510006, People's Republic of China
| | - Sheng-Ming Cheng
- Environmental Research Institute/School of Environment, Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety & MOE Key Laboratory of Theoretical Chemistry of Environment, South China Normal University, Guangzhou, Guangdong 510006, People's Republic of China
| | - Jun Li
- State Key Laboratory of Organic Geochemistry and Guangdong Province Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, Guangdong 510640, People's Republic of China
| | - Guang-Guo Ying
- Environmental Research Institute/School of Environment, Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety & MOE Key Laboratory of Theoretical Chemistry of Environment, South China Normal University, Guangzhou, Guangdong 510006, People's Republic of China
| | - Chang-Er Chen
- Environmental Research Institute/School of Environment, Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety & MOE Key Laboratory of Theoretical Chemistry of Environment, South China Normal University, Guangzhou, Guangdong 510006, People's Republic of China
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Campos-Pereira H, Kleja DB, Ahrens L, Enell A, Kikuchi J, Pettersson M, Gustafsson JP. Effect of pH, surface charge and soil properties on the solid-solution partitioning of perfluoroalkyl substances (PFASs) in a wide range of temperate soils. CHEMOSPHERE 2023; 321:138133. [PMID: 36791815 DOI: 10.1016/j.chemosphere.2023.138133] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2022] [Revised: 02/09/2023] [Accepted: 02/10/2023] [Indexed: 06/18/2023]
Abstract
The pH-dependent soil-water partitioning of six perfluoroalkyl substances (PFASs) of environmental concern (PFOA, PFDA, PFUnDA, PFHxS, PFOS and FOSA), was investigated for 11 temperate mineral soils and related to soil properties such as organic carbon content (0.2-3%), concentrations of Fe and Al (hydr)oxides, and texture. PFAS sorption was positively related to the perfluorocarbon chain length of the molecule, and inversely related to solution pH for all substances. The negative slope between log Kd and pH became steeper with increasing perfluorocarbon chain length of the PFAS (r2 = 0.75, p ≤ 0.05). Organic carbon (OC) alone was a poor predictor of the partitioning for all PFASs, except for FOSA (r2 = 0.71), and the OC-normalized PFAS partitioning, as derived from organic soil materials, underestimated PFAS sorption to the soils. Multiple linear regression suggested sorption contributions (p ≤ 0.05) from OC for perfluorooctane sulfonate (PFOS) and FOSA, and Fe/Al (hydr)oxides for PFOS, FOSA, and perfluorodecanoate (PFDA). FOSA was the only substance under study for which there was a statistically significant correlation between its binding and soil texture (silt + clay). To predict PFAS sorption, the surface net charge of the soil organic matter fraction of all soils was calculated using the Stockholm Humic Model. When calibrated against charge-dependent PFAS sorption to a peat (Oe) material, the derived model significantly underestimated the measured Kd values for 10 out of 11 soils. To conclude, additional sorbents, possibly including silicate minerals, contribute to the binding of PFASs in soil. More research is needed to develop geochemical models that can accurately predict PFAS sorption in soils.
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Affiliation(s)
- Hugo Campos-Pereira
- Department of Soil and Environment, Swedish University of Agricultural Sciences (SLU), Box 7014, SE-750 07, Uppsala, Sweden
| | - Dan B Kleja
- Department of Soil and Environment, Swedish University of Agricultural Sciences (SLU), Box 7014, SE-750 07, Uppsala, Sweden; Swedish Geotechnical Institute (SGI), SE-581 93, Linköping, Sweden
| | - Lutz Ahrens
- Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences (SLU), Box 7050, SE-750 07, Uppsala, Sweden
| | - Anja Enell
- Swedish Geotechnical Institute (SGI), SE-581 93, Linköping, Sweden
| | - Johannes Kikuchi
- Swedish Geotechnical Institute (SGI), SE-581 93, Linköping, Sweden; Department of Thematic Studies, Linköping University, SE-581 83, Linköping, Sweden
| | | | - Jon Petter Gustafsson
- Department of Soil and Environment, Swedish University of Agricultural Sciences (SLU), Box 7014, SE-750 07, Uppsala, Sweden.
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9
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Grimison C, Knight ER, Nguyen TMH, Nagle N, Kabiri S, Bräunig J, Navarro DA, Kookana RS, Higgins CP, McLaughlin MJ, Mueller JF. The efficacy of soil washing for the remediation of per- and poly-fluoroalkyl substances (PFASs) in the field. JOURNAL OF HAZARDOUS MATERIALS 2023; 445:130441. [PMID: 36462244 DOI: 10.1016/j.jhazmat.2022.130441] [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] [Received: 08/10/2022] [Revised: 10/11/2022] [Accepted: 11/17/2022] [Indexed: 06/17/2023]
Abstract
This paper aims to describe the performance of a soil washing plant (SWP) for remediating a per- and poly-fluoroalkyl substances (PFASs)-contaminated soil with a high clay content (61%). The SWP used both physical and chemical processes; fractionation of the soil particles by size and partitioning of PFASs into the aqueous phase to remove PFASs from the soil. Contaminated water was treated in series with granulated activated carbon (GAC) and ion-exchange resin and reused within the SWP. Approximately 2200 t (dry weight) of PFAS-contaminated soil was treated in 25 batches of 90 t each, with a throughput of approximately 11 t soil/hr. Efficiency of the SWP was measured by observed decreases in total and leachable concentrations of PFASs in the soil. Average removal efficiencies (RE) were up to 97.1% for perfluorocarboxylic acids and 94.9% for perfluorosulfonic acids. REs varied among different PFASs depending on their chemistry (functional head group, carbon chain length) and were independent of the total PFAS concentrations in each soil batch. Mass balance analysis found approximately 90% of the PFAS mass in the soil was transferred to the wash solution and > 99.9% of the PFAS mass in the wash solution was transferred onto the GAC without any breakthrough.
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Affiliation(s)
- Charles Grimison
- Ventia Services Pty Limited, Level 8, 80 Pacific Highway, North Sydney, New South Wales, Australia.
| | - Emma R Knight
- Queensland Alliance for Environmental Health Sciences, The University of Queensland, 20 Cornwall Street, Woolloongabba, Queensland, Australia.
| | - Thi Minh Hong Nguyen
- Queensland Alliance for Environmental Health Sciences, The University of Queensland, 20 Cornwall Street, Woolloongabba, Queensland, Australia
| | - Nathan Nagle
- Ventia Services Pty Limited, Level 8, 80 Pacific Highway, North Sydney, New South Wales, Australia
| | - Shervin Kabiri
- School of Agriculture, Food and Wine, Faculty of Sciences, Engineering and Technology, The University of Adelaide, PMB 1 Waite Campus, Glen Osmond, South Australia, Australia
| | - Jennifer Bräunig
- Queensland Alliance for Environmental Health Sciences, The University of Queensland, 20 Cornwall Street, Woolloongabba, Queensland, Australia
| | - Divina A Navarro
- Commonwealth Scientific and Industrial Research Organisation (CSIRO), PMB 2 Land and Water, Waite Campus, South Australia, Australia
| | - Rai S Kookana
- Commonwealth Scientific and Industrial Research Organisation (CSIRO), PMB 2 Land and Water, Waite Campus, South Australia, Australia
| | - Christopher P Higgins
- Queensland Alliance for Environmental Health Sciences, The University of Queensland, 20 Cornwall Street, Woolloongabba, Queensland, Australia; Department of Civil and Environmental Engineering, Colorado School of Mines, Golden, CO 80401, United States
| | - Michael J McLaughlin
- School of Agriculture, Food and Wine, Faculty of Sciences, Engineering and Technology, The University of Adelaide, PMB 1 Waite Campus, Glen Osmond, South Australia, Australia
| | - Jochen F Mueller
- Queensland Alliance for Environmental Health Sciences, The University of Queensland, 20 Cornwall Street, Woolloongabba, Queensland, Australia
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10
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Álvarez-Esmorís C, Rodríguez-López L, Núñez-Delgado A, Álvarez-Rodríguez E, Fernández-Calviño D, Arias-Estévez M. Influence of pH on the adsorption-desorption of doxycycline, enrofloxacin, and sulfamethoxypyridazine in soils with variable surface charge. ENVIRONMENTAL RESEARCH 2022; 214:114071. [PMID: 35995223 DOI: 10.1016/j.envres.2022.114071] [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: 03/21/2022] [Revised: 07/19/2022] [Accepted: 08/04/2022] [Indexed: 06/15/2023]
Abstract
In this research, the adsorption/desorption of the antibiotics doxycycline (DC), enrofloxacin (ENR), and sulfamethoxypyradazine (SMP) was studied in 6 agricultural soils with predominance of variable charge, both before and after removing organic matter by calcination. DC adsorption was high at acidic pH, and decreased at pH values above 8. Removal of organic matter with calcination caused just a slight decrease in adsorption, and even in some soils adsorption was similar to that in non-calcined samples. The adsorption coefficients (Kd) were higher for the DC- species compared to DC+, DC0 and DC2-. Regarding DC desorption, the values were very low throughout the pH range covered in the study (2-12), both in the calcined samples and in those not subjected to calcination. ENR showed a similar behavior to DC regarding the effect of pH, since ENR adsorption also decreased at basic pH, but the effect of removing organic matter was different, as it caused a clear decrease in ENR adsorption. The species with the highest Kd was in this case ENR0, although ENR+ is also quantitatively important as regards Kd value in calcined samples. For this antibiotic, no differences in desorption were observed between calcined and non-calcined samples. Finally, SMP adsorption also decreased as pH increased, and, in addition, similarly to what happened with ENR, in general, there was a strong decrease in SMP adsorption when organic matter was removed. The species with the highest Kd in this case was SMP+ in non-calcined samples, but SMP0 and SMP- become more relevant in calcined samples. The percentages of SMP desorption were higher than those for the other two antibiotics, and an increase occurs at intermediate pH values, being higher for calcined samples. These results can be considered relevant in terms of increasing the knowledge as regards the possible evolution and fate of the three antibiotics studied. Specifically, for different pH conditions and with different organic matter contents, when they reach soils and other environmental compartments after being discharged as contaminants. This could have important repercussions on public health and the overall environment.
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Affiliation(s)
| | - Lucia Rodríguez-López
- Soil Science and Agricultural Chemistry, Fac. Sciences, Univ. Vigo, 32004, Ourense, Spain
| | - Avelino Núñez-Delgado
- Dept. Soil Science and Agricultural Chemistry, Engineering Polytechnic School, Univ. Santiago de Compostela, 27002, Lugo, Spain
| | - Esperanza Álvarez-Rodríguez
- Dept. Soil Science and Agricultural Chemistry, Engineering Polytechnic School, Univ. Santiago de Compostela, 27002, Lugo, Spain
| | | | - Manuel Arias-Estévez
- Soil Science and Agricultural Chemistry, Fac. Sciences, Univ. Vigo, 32004, Ourense, Spain.
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11
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Li XQ, Hua ZL, Zhang JY, Gu L. Interactions between dissolved organic matter and perfluoroalkyl acids in natural rivers and lakes: A case study of the northwest of Taihu Lake Basin, China. WATER RESEARCH 2022; 216:118324. [PMID: 35339055 DOI: 10.1016/j.watres.2022.118324] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2022] [Revised: 03/07/2022] [Accepted: 03/17/2022] [Indexed: 06/14/2023]
Abstract
Understanding the interactions between dissolved organic matter (DOM) and perfluoroalkyl acids (PFAAs) is essential for predicting the distribution, transport, and fate of PFAAs in aquatic environments. Based on field investigations in the northwest of Taihu Lake Basin combined with laboratory experiments, we obtained DOM and PFAA concentrations as well as compositions and investigated key factors of DOM affecting PFAA variability and capture of PFAAs by DOM. Results indicated that the total concentrations of PFAAs were 73.4-689 ng/L in surface water and that PFAAs were dominated by C3-7 perfluoroalkyl carboxylic acids and perfluorooctane sulfonic acid. The main components of DOM included tyrosine-, fulvic-, and tryptophan-like substances. The Mantel test revealed a significant positive correlation between DOM and PFAAs (P = 0.0001). Fulvic-like substances were identified as the most crucial factors affecting PFAA variability. The laboratory experiments revealed that DOM can spontaneously aggregate into a microgel. Furthermore, 19.1-50.9% of PFAAs, DOM characteristic peaks, and several metals (Ca, Mg, Cu, and Fe) can be removed during aggregation, indicating the capacity of DOM binding organic/inorganic substances. The fulvic-like substances were more effectively removed than the protein-like substances. The distribution coefficients of all PFAAs except perfluorohexanoic acid significantly correlated with their perfluorinated carbon numbers (r = 0.975, p<0.001). Our results provided insights into the interactions between DOM and PFAAs, improving the understanding of the distribution, transport, and fate of PFAAs in aquatic environments.
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Affiliation(s)
- Xiao-Qing Li
- Ministry of Education Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Hohai University, Nanjing 210098, PR China.
| | - Zu-Lin Hua
- Ministry of Education Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Hohai University, Nanjing 210098, PR China; Yangtze Institute for Conservation and Development, Jiangsu, 210098, PR China.
| | - Jian-Yun Zhang
- Yangtze Institute for Conservation and Development, Jiangsu, 210098, PR China
| | - Li Gu
- Ministry of Education Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Hohai University, Nanjing 210098, PR China; Yangtze Institute for Conservation and Development, Jiangsu, 210098, PR China
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12
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Cai W, Navarro DA, Du J, Ying G, Yang B, McLaughlin MJ, Kookana RS. Increasing ionic strength and valency of cations enhance sorption through hydrophobic interactions of PFAS with soil surfaces. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 817:152975. [PMID: 35026264 DOI: 10.1016/j.scitotenv.2022.152975] [Citation(s) in RCA: 41] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Revised: 12/20/2021] [Accepted: 01/04/2022] [Indexed: 06/14/2023]
Abstract
The effect of soluble cations on sorption in soils of a range of anionic PFAS is not well studied. We investigated the role of three common cations (Na+, Ca2+, and Mg2+) at varying solution concentrations on the sorption coefficients (Kd) of 18 anionic PFAS in two contrasting soils. The effective charge of the soil suspension (Zeta potential) became less negative as the concentration of these cations increased in the soil solutions. Perfluorinated compounds showed greater sorption than polyfluorinated compounds, with sulfonates of comparable chain lengths showing higher sorption than the carboxylates. We observed that the Kd values of several PFAS in the two soils were positively correlated with the concentration of cations in solution, especially in the presence of polyvalent cations (Ca2+and Mg2+). The changes in sorption with cation concentration were more prominent for long-chain PFAS, with C > 10 PFAS being completely removed from solution at higher cation concentrations. The emerging PFAS (replacement compounds GenX and ADONA) showed negligible or little sorption (Kd < 0.6 L/kg). While several mechanisms contribute towards sorption of PFAS in the presence of cations, we conclude that the primary effect of cations is through screening of negative charges on head groups of PFAS and reorientation of molecules at the interface between organic matter surfaces and soil solution as well as charge neutralisation at soil solid surface. Screening of negative charges allows for greater hydrophobic interaction between hydrophobic tails of PFAS and soil surfaces resulting in greater sorption. Increasing cation concentrations in soil solutions could thus reduce mobility of PFAS through a soil profile.
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Affiliation(s)
- Wenwen Cai
- School of Environment, Key Laboratory for Yellow River and Huai River Water Environment and Pollution Control, Ministry of Education, Henan Normal University, Xinxiang 453007, China; State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; CSIRO Land and Water, Locked Bag 2, Glen Osmond 5064, Australia
| | - Divina A Navarro
- CSIRO Land and Water, Locked Bag 2, Glen Osmond 5064, Australia; University of Adelaide, Waite Campus, Locked Bag 1, Glen Osmond 5064, Australia.
| | - Jun Du
- CSIRO Land and Water, Locked Bag 2, Glen Osmond 5064, Australia
| | - Guangguo Ying
- School of Environment, South China Normal University, Guangzhou 510006, China
| | - Bin Yang
- School of Environment, South China Normal University, Guangzhou 510006, China
| | - Mike J McLaughlin
- University of Adelaide, Waite Campus, Locked Bag 1, Glen Osmond 5064, Australia
| | - Rai S Kookana
- CSIRO Land and Water, Locked Bag 2, Glen Osmond 5064, Australia; University of Adelaide, Waite Campus, Locked Bag 1, Glen Osmond 5064, Australia
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13
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Wang W, Rhodes G, Zhang W, Yu X, Teppen BJ, Li H. Implication of cation-bridging interaction contribution to sorption of perfluoroalkyl carboxylic acids by soils. CHEMOSPHERE 2022; 290:133224. [PMID: 34896418 DOI: 10.1016/j.chemosphere.2021.133224] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Revised: 11/19/2021] [Accepted: 12/06/2021] [Indexed: 06/14/2023]
Abstract
Sorption of four perfluoroalkyl carboxylic acids (PFCAs) including perfluoropentanoic acid, perfluoroheptanoic acid, perfluorodecanoic acid, and perfluorododecanoic acid by three soils with cation exchange sites occupied by K+, Ca2+, or Fe3+ was measured using the batch equilibration method. We hypothesize that partitioning in soil organic matters (SOM) is the primarily operative mechanism for PFCA sorption by K+-soils, and sorption by Ca2+- or Fe3+-soils could be enhanced via cation-bridging interaction. The measured sorption isotherms for all four PFCAs by soils were linear within the aqueous concentration between 0 and 60 μg/L, and the distribution coefficients ranged between 14.8 and 173 L/kg. Long-chain PFCAs manifested greater sorption by the soils with higher SOM content. Compared to sorption by K+-soils, sorption of PFCAs by Ca2+- and Fe3+-soils increased by 19.9-90.2% and 38.5-219%, respectively. The relative contributions of cation-bridging interaction to the overall PFCA sorption were estimated to be 16.6-48.7% for Ca2+-soils and 27.8-67.7% for Fe3+-soils. These results demonstrate that multivalent exchangeable cations could play an important role, yet previously ignored, in controlling sorption and transport of PFCAs in soils.
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Affiliation(s)
- Wenfeng Wang
- Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing, MI, 48824, USA; Jiangsu Key Laboratory for Food Quality and Safety, State Key Laboratory Cultivation Base of Ministry of Science and Technology, Jiangsu Academy of Agricultural Sciences, 50 Zhongling Street, Nanjing, 210014, China
| | - Geoff Rhodes
- Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing, MI, 48824, USA
| | - Wei Zhang
- Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing, MI, 48824, USA
| | - Xiangyang Yu
- Jiangsu Key Laboratory for Food Quality and Safety, State Key Laboratory Cultivation Base of Ministry of Science and Technology, Jiangsu Academy of Agricultural Sciences, 50 Zhongling Street, Nanjing, 210014, China
| | - Brian J Teppen
- Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing, MI, 48824, USA
| | - Hui Li
- Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing, MI, 48824, USA.
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14
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McMahon PB, Tokranov AK, Bexfield LM, Lindsey BD, Johnson TD, Lombard MA, Watson E. Perfluoroalkyl and Polyfluoroalkyl Substances in Groundwater Used as a Source of Drinking Water in the Eastern United States. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:2279-2288. [PMID: 35113548 PMCID: PMC8970425 DOI: 10.1021/acs.est.1c04795] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
In 2019, 254 samples were collected from five aquifer systems to evaluate perfluoroalkyl and polyfluoroalkyl substance (PFAS) occurrence in groundwater used as a source of drinking water in the eastern United States. The samples were analyzed for 24 PFAS, major ions, nutrients, trace elements, dissolved organic carbon (DOC), volatile organic compounds (VOCs), pharmaceuticals, and tritium. Fourteen of the 24 PFAS were detected in groundwater, with 60 and 20% of public-supply and domestic wells, respectively, containing at least one PFAS detection. Concentrations of tritium, chloride, sulfate, DOC, and manganese + iron; percent urban land use within 500 m of the wells; and VOC and pharmaceutical detection frequencies were significantly higher in samples containing PFAS detections than in samples with no detections. Boosted regression tree models that consider 57 chemical and land-use variables show that tritium concentration, distance to the nearest fire-training area, percentage of urban land use, and DOC and VOC concentrations are the top five predictors of PFAS detections, consistent with the hydrologic position, geochemistry, and land use being important controls on PFAS occurrence in groundwater. Model results indicate that it may be possible to predict PFAS detections in groundwater using existing data sources.
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Affiliation(s)
- Peter B. McMahon
- U.S.
Geological Survey, Bldg. 53, MS 415, Lakewood, Colorado, 80225, United States
- .
Tel.: 303-236-6899
| | - Andrea K. Tokranov
- U.S.
Geological Survey, 10 Bearfoot Rd., Northborough, Massachusetts 01532, United States
| | - Laura M. Bexfield
- U.S.
Geological Survey, 6700 Edith Blvd NE, Albuquerque, New Mexico 87113, United States
| | - Bruce D. Lindsey
- U.S.
Geological Survey, 215 Limekiln Road, New Cumberland, Pennsylvania 17070, United States
| | - Tyler D. Johnson
- U.S.
Geological Survey, 4165 Spruance Road, San Diego, California 92101, United States
| | - Melissa A. Lombard
- U.S. Geological
Survey, 331 Commerce Way, Pembroke, New Hampshire 03275, United States
| | - Elise Watson
- U.S.
Geological Survey, 4165 Spruance Road, San Diego, California 92101, United States
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15
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He Y, Yang M, Huang R, Wang Y, Ali W. Soil organic matter and clay zeta potential influence aggregation of a clayey red soil (Ultisol) under long-term fertilization. Sci Rep 2021; 11:20498. [PMID: 34654873 PMCID: PMC8519938 DOI: 10.1038/s41598-021-99769-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2021] [Accepted: 09/30/2021] [Indexed: 11/09/2022] Open
Abstract
The effect of soil organic matter (SOM) on aggregation of variably-charged red soils (Ultisol) through clay zeta potential is not fully understood. Therefore, the objectives of this study were to investigate the SOM effect on the clay zeta potential and soil aggregation after fertilization. Soils under 17 years of fertilization (manure, NPK + straw, NPK, and control (CK) were adjusted by KCl solution to reach varying soil pH and concentration in order to determine clay zeta potential, cations, and aggregate size distribution. The SOM content and C-functional groups by 13C-NMR analysis were also determined. Results showed that the negative zeta potential displayed a bell-shaped pattern with increasing concentration of KCl, but displayed different amplitude of variation among treatments. Manure had the highest zeta potential value and its degree of variation in relative to the value at KCl concentration of 0.1 mol L-1 (19%), NPK + straw and NPK treatments were similar, and CK was the least. Greater negative zeta potential for manure treatment was attributed to higher SOM content, aromatic-C functional groups, and their greater concentrations of Ca2+ and Mg2+ than did the CK. As a result, higher SOM and clay zeta potential yielded in less release of amount of soil particles (< 10 μm) (r = - 0.46*) and enhanced water stable macroaggregates for manure instead of NPK + straw. Long-term manure fertilization would be suggested as a conservation practice for red soil due to its increase in soil aggregate stability and negative zeta potential in subtropical climate.
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Affiliation(s)
- Yangbo He
- Key Laboratory of Arable Land Conservation, Ministry of Agriculture and Rural Affairs, Huazhong Agricultural University, Wuhan, Hubei, China.
| | - Mingxuan Yang
- Key Laboratory of Arable Land Conservation, Ministry of Agriculture and Rural Affairs, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Rui Huang
- Key Laboratory of Arable Land Conservation, Ministry of Agriculture and Rural Affairs, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Yao Wang
- Key Laboratory of Arable Land Conservation, Ministry of Agriculture and Rural Affairs, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Waqar Ali
- Key Laboratory of Arable Land Conservation, Ministry of Agriculture and Rural Affairs, Huazhong Agricultural University, Wuhan, Hubei, China
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16
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Chen C, Ma Q, Liu F, Gao J, Li X, Sun S, Yao H, Liu C, Young J, Zhang W. Photocatalytically reductive defluorination of perfluorooctanoic acid (PFOA) using Pt/La 2Ti 2O 7 nanoplates: Experimental and DFT assessment. JOURNAL OF HAZARDOUS MATERIALS 2021; 419:126452. [PMID: 34198220 DOI: 10.1016/j.jhazmat.2021.126452] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 06/18/2021] [Accepted: 06/19/2021] [Indexed: 06/13/2023]
Abstract
To enable efficient degradation of perfluorooctanoic acid (PFOA), we prepared and investigated a nanosheet photocatalyst (Pt/La2Ti2O7). Doping platinum nanoparticles on La2Ti2O7 varied the band structure and improved the photocatalytic activity due to the enhanced charge separation. Methanol as the electron donor and sacrificial reagent significantly promoted the photocatalytically reductive degradation of PFOA that reduced by 40% within 180 min under UV254 irradiation (1 mW∙cm2). The density functional theory calculations were used to analyze the effects of Pt doping and band structures on interfacial electron transfer and degradation pathways. As opposed to photocatalytic oxidation, this UV/Pt/La2Ti2O7/CH3OH photocatalysis could abstract electrons from methanol and convert to free reactive radicals and photo-generated electrons to reductively defluorinate PFOA and potentially other polyhalogenated or perhalogenated organic compounds.
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Affiliation(s)
- Chen Chen
- Department of Municipal and Environmental Engineering, Qingdao University of Technology, Qingdao 266033, PR China; John A. Reif, Jr. Department of Civil and Environmental Engineering, New Jersey Institute of Technology, Newark, NJ 07102, USA
| | - Qingquan Ma
- John A. Reif, Jr. Department of Civil and Environmental Engineering, New Jersey Institute of Technology, Newark, NJ 07102, USA
| | - Fangzhou Liu
- John A. Reif, Jr. Department of Civil and Environmental Engineering, New Jersey Institute of Technology, Newark, NJ 07102, USA
| | - Jianan Gao
- Department of Municipal and Environmental Engineering, Qingdao University of Technology, Qingdao 266033, PR China; John A. Reif, Jr. Department of Civil and Environmental Engineering, New Jersey Institute of Technology, Newark, NJ 07102, USA
| | - Xinyang Li
- Beijing International Scientific and Technological Cooperation Base of Water Pollution Control Techniques for Antibiotics and Resistance Genes, Beijing Key Laboratory of Aqueous Typical Pollutants Control and Water Quality Safeguard, Department of municipal and environmental Engineering, School of civil engineering, Beijing Jiaotong University, Beijing 100044, PR China
| | - Shaobin Sun
- Beijing International Scientific and Technological Cooperation Base of Water Pollution Control Techniques for Antibiotics and Resistance Genes, Beijing Key Laboratory of Aqueous Typical Pollutants Control and Water Quality Safeguard, Department of municipal and environmental Engineering, School of civil engineering, Beijing Jiaotong University, Beijing 100044, PR China
| | - Hong Yao
- Beijing International Scientific and Technological Cooperation Base of Water Pollution Control Techniques for Antibiotics and Resistance Genes, Beijing Key Laboratory of Aqueous Typical Pollutants Control and Water Quality Safeguard, Department of municipal and environmental Engineering, School of civil engineering, Beijing Jiaotong University, Beijing 100044, PR China
| | - Changqing Liu
- Department of Municipal and Environmental Engineering, Qingdao University of Technology, Qingdao 266033, PR China
| | - Joshua Young
- Otto H. York Department of Chemical and Materials Engineering, New Jersey Institute of Technology, Newark, NJ 07102, USA
| | - Wen Zhang
- John A. Reif, Jr. Department of Civil and Environmental Engineering, New Jersey Institute of Technology, Newark, NJ 07102, USA; Otto H. York Department of Chemical and Materials Engineering, New Jersey Institute of Technology, Newark, NJ 07102, USA.
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17
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Kabiri S, Centner M, McLaughlin MJ. Durability of sorption of per- and polyfluorinated alkyl substances in soils immobilised using common adsorbents: 1. Effects of perturbations in pH. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 766:144857. [PMID: 33446338 DOI: 10.1016/j.scitotenv.2020.144857] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2020] [Revised: 12/13/2020] [Accepted: 12/21/2020] [Indexed: 06/12/2023]
Abstract
The global problem of groundwater being contaminated with per- and polyfluoroalkyl substances (PFASs) originating from highly contaminated soils has created a need to remediate these locations. In situ immobilisation of PFASs in soil by applying sorbents is often a preferred low-cost technique to reduce their mobility and leaching to groundwater, but the long-term efficacy of sorbents has not yet been investigated. In this study, the longevity of remediation of two different soils by two common sorbents (RemBind®, and pulverized activated carbon, Filtrasorb™ 400) was assessed. Regulatory agencies often rely on standardised leaching procedures to assess the risk of contaminant mobility in soils. Hence, the Australian Standard Leaching Procedure and the U.S. EPA Leaching Environmental Assessment Framework were applied to quantify the desorption/leaching of a wide range of PFASs from unremediated and remediated soils under a range of pH conditions (pH 2 to 12). Ease of desorption and subsequent leaching from the unremediated soils was related to C-chain length; while short-chain PFASs were easily desorbed and leached, long-chain PFASs were more difficult to desorb. Desorption of long-chain PFASs was also pH dependent in unremediated soils, with desorption being greater at high pH. Both sorbents retained PFASs strongly in the remediated soils (> 99% for most PFASs) across a broad range of pH conditions, with only small differences between the sorbents in terms of efficacy. Both sorbents showed better retention of PFASs under low pH conditions. Remediation of PFAS-contaminated soils with these sorbents could be considered robust and durable in terms of changes in soil pH, with little risk of subsequent PFASs desorption under normal environmental pH conditions. Ultimately, to give regulators and site owners the greatest level of confidence that immobilisation is stable for the longer term, it should also be tested under repeated cycles of leaching and under different conditions.
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Affiliation(s)
- Shervin Kabiri
- School of Agriculture, Food and Wine, The University of Adelaide, PMB 1, Waite Campus, Glen Osmond, SA 5064, Australia.
| | - Marc Centner
- ALS, Life Sciences Division, 277 Woodpark Road Smithfield, NSW 2164, Australia
| | - Michael J McLaughlin
- School of Agriculture, Food and Wine, The University of Adelaide, PMB 1, Waite Campus, Glen Osmond, SA 5064, Australia.
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18
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Li J, Zheng T, Liu C. Soil acidification enhancing the growth and metabolism inhibition of PFOS and Cr(VI) to bacteria involving oxidative stress and cell permeability. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2021; 275:116650. [PMID: 33581635 DOI: 10.1016/j.envpol.2021.116650] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Revised: 01/20/2021] [Accepted: 02/01/2021] [Indexed: 06/12/2023]
Abstract
Soil acidification is causing more and more attention, not only because of the harm of acidification itself, but also the greater harm to bacteria brought by some pollutants under acidic condition. Therefore, the toxicities of two typical soil pollutants (perfluorooctane sulfonate (PFOS) and chromium (Cr(VI)) to growth and metabolisms of soil bacteria (Bacillus subtilis as modol) were investigated. Under acidic condition of pH = 5, Cr(VI), PFOS and PFOS + Cr(VI) show stronge inhibition to bacteria growth up to 24.3%, 42.3%, 41.6%, respectively, and this inhibition was about 2-3 times of that at pH = 7. Moreover, acid stress reduces the metabolism of bacteria, while PFOS and Cr(VI) pollution futher strengthens this metabolic inhibition involving oxidative stress and cell permeability. The activities of dehydrogenase (DHA) and electron transport system (ETS) at pH = 5 exposed to Cr(VI), PFOS and combined PFOS + Cr(VI) was 21.5%, 16.9%, 23.2% and 8.9%, 32.2%, 19.1% lower than the control, respectively. However, the relative activity of DHA and ETS at pH = 7 are 5-8 and 2-13 times of that at pH = 5, respectively. Isoelectric point, cell surface hydrophobicity and molecular simulation analysis show that the corresponding mechanism is that acidic conditions enhance the interaction between bacteria and PFOS/Cr(VI) through hydrogen bonding, hydrophobic and electrostatic interactions. The results can guide the remediation of acid soil pollution, and provide a reference for the combined toxicity evaluation of heavy metals and micro-pollutants in acid soil.
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Affiliation(s)
- Jie Li
- School of Environmental Science and Engineering, Shandong Provincial Key Laboratory of Water Pollution Control and Resource Reuse, China-America CRC for Environment & Health of Shandong Province, Shandong University, 72# Jimo Binhai Road, Qingdao, Shandong, 266237, PR China.
| | - Tongtong Zheng
- School of Environmental Science and Engineering, Shandong Provincial Key Laboratory of Water Pollution Control and Resource Reuse, China-America CRC for Environment & Health of Shandong Province, Shandong University, 72# Jimo Binhai Road, Qingdao, Shandong, 266237, PR China.
| | - Chunguang Liu
- School of Environmental Science and Engineering, Shandong Provincial Key Laboratory of Water Pollution Control and Resource Reuse, China-America CRC for Environment & Health of Shandong Province, Shandong University, 72# Jimo Binhai Road, Qingdao, Shandong, 266237, PR China; Guangzhou Key Laboratory of Environmental Exposure and Health, School of Environment, Jinan University, PR China.
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19
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Zhu X, Song X, Schwarzbauer J. First insights into the formation and long-term dynamic behaviors of nonextractable perfluorooctanesulfonate and its alternative 6:2 chlorinated polyfluorinated ether sulfonate residues in a silty clay soil. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 761:143230. [PMID: 33158517 DOI: 10.1016/j.scitotenv.2020.143230] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Revised: 10/15/2020] [Accepted: 10/17/2020] [Indexed: 06/11/2023]
Abstract
Per- and polyfluoroalkyl substances (PFAS) are persistent and toxic contaminants that are ubiquitous in the environment. They can incorporate into soil as nonextractable residues (NER) which are not detectable with conventional analytical protocols but are still possible to remobilize with changes of surrounding conditions, and thus will be bioavailable again. Therefore, there is a need to investigate thoroughly the long-term fate of NER-PFAS. In this study, a 240-day incubation of perfluorooctanesulfonate (PFOS) and its alternative 6:2 chlorinated polyfluorinated ether sulfonate (F-53B) in a silty clay topsoil was carried out. Solvent extraction, alkaline hydrolysis and sequential chemical degradation were applied on periodically sampled soil to obtain extractable, moderately bound and deeply bound PFAS, respectively. The results confirmed the formation of NER of both compounds but with different preferences of incorporating mechanisms. NER-PFOS was formed predominantly by covalent binding (via head group) and strong adsorption (via tail group). The formation of NER-F-53B was mainly driven by physical entrapment. Both bound compounds within the incubation period showed three-stage behaviors including an initial period with slight release followed by a (re) incorporating stage and a subsequent remobilizing stage. This work provides some first insights on the long-term dynamic behaviors of nonextractable PFAS and will be conducive to their risk assessment and remediation (e.g. estimating potential NER-PFAS level based on their free extractable level, and selecting remediation methods according to their prevailing binding mechanisms).
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Affiliation(s)
- Xiaojing Zhu
- Institute of Geology and Geochemistry of Petroleum and Coal, RWTH Aachen University, Lochnerstr, 4-20, 52064 Aachen, Germany.
| | - Xin Song
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, 210008 Nanjing, China.
| | - Jan Schwarzbauer
- Institute of Geology and Geochemistry of Petroleum and Coal, RWTH Aachen University, Lochnerstr, 4-20, 52064 Aachen, Germany.
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20
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Knight ER, Bräunig J, Janik LJ, Navarro DA, Kookana RS, Mueller JF, McLaughlin MJ. An investigation into the long-term binding and uptake of PFOS, PFOA and PFHxS in soil - plant systems. JOURNAL OF HAZARDOUS MATERIALS 2021; 404:124065. [PMID: 33069992 DOI: 10.1016/j.jhazmat.2020.124065] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Revised: 08/28/2020] [Accepted: 09/20/2020] [Indexed: 06/11/2023]
Abstract
This study investigated the potential aging and plant bioaccumulation of three perfluoroalkyl acids (PFAAs), perfluorosulphonic acid (PFOS), perfluorooctanoic acid (PFOA) and perfluorohexanesulphonic acid (PFHxS) in 20 soils over a six-month period. Sorption coefficients (Log Kd) ranged from 0.13-1.28 for PFHxS, 0.17-1.06 for PFOA and 0.98-2.03 for PFOS, respectively, and bioaccumulation factors (Log BAFs) ranged from 0.29-1.24, 0.22-1.46 and 0.05-0.65 for PFHxS, PFOA and PFOS, respectively. Over the six-month period, Kd values significantly increased for PFHxS and PFOA but the magnitude of the increase was very small and did not translate into differences in plant PFAA-concentrations between aged and freshly spiked treatments. The Kd and BAF values were modelled by multiple linear regression (MLR) to soil physico-chemical properties and by partial least squares regression to soil spectra acquired by mid-infrared spectroscopy (DRIFT-PLSR). Modelling of each PFAA was influenced by different soil properties, including organic carbon, pH, CEC, exchangeable cations (Ca2+, Mg2+, Na+ and K+) and oxalate extractable Al. BAF values were not strongly correlated to any soil property but were inversely correlated to Kd values. Our results indicate that limited aging occurred in these soils over the six-month period.
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Affiliation(s)
- Emma R Knight
- School of Agriculture, Food and Wine, Faculty of Sciences, The University of Adelaide, PMB 1 Waite Campus, Glen Osmond, South Australia, Australia; Commonwealth Scientific and Industrial Research Organisation, PMB 2 Land and Water, Waite Campus, South Australia, Australia.
| | - Jennifer Bräunig
- Queensland Alliance for Environmental Health Sciences, The University of Queensland, 20 Cornwall Street, Woolloongabba, Queensland, Australia
| | - Leslie J Janik
- School of Agriculture, Food and Wine, Faculty of Sciences, The University of Adelaide, PMB 1 Waite Campus, Glen Osmond, South Australia, Australia
| | - Divina A Navarro
- Commonwealth Scientific and Industrial Research Organisation, PMB 2 Land and Water, Waite Campus, South Australia, Australia
| | - Rai S Kookana
- School of Agriculture, Food and Wine, Faculty of Sciences, The University of Adelaide, PMB 1 Waite Campus, Glen Osmond, South Australia, Australia
| | - Jochen F Mueller
- Queensland Alliance for Environmental Health Sciences, The University of Queensland, 20 Cornwall Street, Woolloongabba, Queensland, Australia
| | - Michael J McLaughlin
- School of Agriculture, Food and Wine, Faculty of Sciences, The University of Adelaide, PMB 1 Waite Campus, Glen Osmond, South Australia, Australia
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21
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Umeh AC, Naidu R, Shilpi S, Boateng EB, Rahman A, Cousins IT, Chadalavada S, Lamb D, Bowman M. Sorption of PFOS in 114 Well-Characterized Tropical and Temperate Soils: Application of Multivariate and Artificial Neural Network Analyses. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:1779-1789. [PMID: 33449633 DOI: 10.1021/acs.est.0c07202] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The influence of soil properties on PFOS sorption are not fully understood, particularly for variable charge soils. PFOS batch sorption isotherms were conducted for 114 temperate and tropical soils from Australia and Fiji, that were well-characterized for their soil properties, including total organic carbon (TOC), anion exchange capacity, and surface charge. In most soils, PFOS sorption isotherms were nonlinear. PFOS sorption distribution coefficients (Kd) ranged from 5 to 229 mL/g (median: 28 mL/g), with 63% of the Fijian soils and 35% of the Australian soils showing Kd values that exceeded the observed median Kd. Multiple linear regression showed that TOC, amorphous aluminum and iron oxides contents, anion exchange capacity, pH, and silt content, jointly explained about 53% of the variance in PFOS Kd in soils. Variable charge soils with net positive surface charges, and moderate to elevated TOC content, generally displayed enhanced PFOS sorption than in temperate or tropical soils with TOC as the only sorbent phase, especially at acidic pH ranges. For the first time, two artificial neural networks were developed to predict the measured PFOS Kd (R2 = 0.80) in the soils. Overall, both TOC and surface charge characteristics of soils are important for describing PFOS sorption.
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Affiliation(s)
- Anthony C Umeh
- Global Centre for Environmental Remediation (GCER), University of Newcastle, Callaghan, New South Wales 2308, Australia
- Cooperative Research Centre for Contamination Assessment and Remediation of the Environment (CRC CARE), University of Newcastle, Callaghan, New South Wales 2308, Australia
| | - Ravi Naidu
- Global Centre for Environmental Remediation (GCER), University of Newcastle, Callaghan, New South Wales 2308, Australia
- Cooperative Research Centre for Contamination Assessment and Remediation of the Environment (CRC CARE), University of Newcastle, Callaghan, New South Wales 2308, Australia
| | - Sonia Shilpi
- Global Centre for Environmental Remediation (GCER), University of Newcastle, Callaghan, New South Wales 2308, Australia
| | - Emmanuel B Boateng
- School of Health Sciences, University of Newcastle, Callaghan, New South Wales 2308, Australia
- Department of Civil and Construction Engineering, Swinburne University of Technology, Victoria 3122, Australia
| | - Aminur Rahman
- Global Centre for Environmental Remediation (GCER), University of Newcastle, Callaghan, New South Wales 2308, Australia
| | - Ian T Cousins
- Department of Environmental Science, Stockholm University, SE-10691, Stockholm, Sweden
| | - Sreenivasulu Chadalavada
- Cooperative Research Centre for Contamination Assessment and Remediation of the Environment (CRC CARE), University of Newcastle, Callaghan, New South Wales 2308, Australia
| | - Dane Lamb
- Global Centre for Environmental Remediation (GCER), University of Newcastle, Callaghan, New South Wales 2308, Australia
| | - Mark Bowman
- Australian Department of Defence, BP26-2-B009, Brindabella Business Park, Canberra Airport, Deakin ACT 2600, Australia
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22
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Xing Y, Li Q, Chen X, Fu X, Ji L, Wang J, Li T, Zhang Q. Different transport behaviors and mechanisms of perfluorooctanoate (PFOA) and perfluorooctane sulfonate (PFOS) in saturated porous media. JOURNAL OF HAZARDOUS MATERIALS 2021; 402:123435. [PMID: 32717541 DOI: 10.1016/j.jhazmat.2020.123435] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Revised: 06/10/2020] [Accepted: 07/06/2020] [Indexed: 06/11/2023]
Abstract
Perfluorooctanoate (PFOA) and perfluorooctane sulfonate (PFOS) in soil aroused increasing concern, however there is little information about their transport in porous media, which is urgently needed to better control their environmental risks. In this study, saturated sand columns (considering the coupled effect of solution cation type and pH) and a two-site nonequilibrium transport model (TSM) were used to investigate the transport behaviors and mechanisms of PFOA and PFOS. Breakthrough data and the TSM parameters showed PFOA had higher mobility than PFOS, and divalent cation could inhibit their transport by increasing the nonequilibrium interactions between them and the sand. pH had little influence on PFOA migration when there was only monovalent cation in the solution since PFOA had limited affinity with the sand, however, polyvalent cation could provide additional adsorption sites for it through cation bridging and enhance the effect of pH. Differently, decreasing pH inhibited the transport of PFOS more significantly, and the effect was stronger than that of changing cation type. That proved mechanisms like hydrogen-bonding which were sensitive to solution pH played an important role in PFOS migration. These results provide important scientific basis to the remediation strategy and the migration prediction model development of PFOA and PFOS.
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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
| | - Xiaowen Fu
- Shandong Provincial Key Laboratory of Applied Microbiology, Ecology Institute, Qilu University of Technology (Shandong Academy of Sciences), Jinan, 250103, China
| | - Lei Ji
- 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
| | - Tianyuan Li
- 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.
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23
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Campos-Pereira H, Kleja DB, Sjöstedt C, Ahrens L, Klysubun W, Gustafsson JP. The Adsorption of Per- and Polyfluoroalkyl Substances (PFASs) onto Ferrihydrite Is Governed by Surface Charge. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:15722-15730. [PMID: 33244971 PMCID: PMC7745537 DOI: 10.1021/acs.est.0c01646] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Revised: 10/30/2020] [Accepted: 11/08/2020] [Indexed: 06/11/2023]
Abstract
An improved quantitative and qualitative understanding of the interaction of per- and polyfluoroalkyl substances (PFASs) and short-range ordered Fe (hydr)oxides is crucial for environmental risk assessment in environments low in natural organic matter. Here, we present data on the pH-dependent sorption behavior of 12 PFASs onto ferrihydrite. The nature of the binding mechanisms was investigated by sulfur K-edge X-ray absorption near-edge structure (XANES) spectroscopy and by phosphate competition experiments. Sulfur K-edge XANES spectroscopy showed that the sulfur atom of the head group of the sulfonated PFASs retained an oxidation state of +V after adsorption. Furthermore, the XANES spectra did not indicate any involvement of inner-sphere surface complexes in the sorption process. Adsorption was inversely related to pH (p < 0.05) for all PFASs (i.e., C3-C5 and C7-C9 perfluorocarboxylates, C4, C6, and C8 perfluorosulfonates, perfluorooctane sulfonamide, and 6:2 and 8:2 fluorotelomer sulfonates). This was attributed to the pH-dependent charge of the ferrihydrite surface, as reflected in the decrease of surface ζ-potential with increasing pH. The importance of surface charge for PFAS adsorption was further corroborated by the observation that the adsorption of PFASs decreased upon phosphate adsorption in a way that was consistent with the decrease in ferrihydrite ζ-potential. The results show that ferrihydrite can be an important sorbent for PFASs with six or more perfluorinated carbons in acid environments (pH ≤ 5), particularly when phosphate and other competitors are present in relatively low concentrations.
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Affiliation(s)
- Hugo Campos-Pereira
- Department
of Soil and Environment, Swedish University
of Agricultural Sciences (SLU), P.O. Box 7014, SE-750 07 Uppsala, Sweden
| | - Dan B. Kleja
- Department
of Soil and Environment, Swedish University
of Agricultural Sciences (SLU), P.O. Box 7014, SE-750 07 Uppsala, Sweden
- Swedish
Geotechnical Institute (SGI), SE-581 93 Linköping, Sweden
| | - Carin Sjöstedt
- Department
of Soil and Environment, Swedish University
of Agricultural Sciences (SLU), P.O. Box 7014, SE-750 07 Uppsala, Sweden
| | - Lutz Ahrens
- Department
of Aquatic Sciences and Assessment, Swedish
University of Agricultural Sciences (SLU), P.O. Box 7014, SE-750 07 Uppsala, Sweden
| | - Wantana Klysubun
- Synchrotron
Light Research Institute, 111 Moo 6, Suranaree, Muang, Nakhon Ratchasima 30000, Thailand
| | - Jon Petter Gustafsson
- Department
of Soil and Environment, Swedish University
of Agricultural Sciences (SLU), P.O. Box 7014, SE-750 07 Uppsala, Sweden
- Department
of Sustainable Development, Environmental Science and Engineering, KTH Royal Institute of Technology, Teknikringen 10B, SE-100 44 Stockholm, Sweden
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24
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Hua H, Zhao Z, Xu R, Chang E, Fang D, Dong Y, Hong Z, Shi R, Jiang J. Effect of ferrolysis and organic matter accumulation on chromate adsorption characteristics of an Oxisol-derived paddy soil. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 744:140868. [PMID: 32717467 DOI: 10.1016/j.scitotenv.2020.140868] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2020] [Revised: 06/14/2020] [Accepted: 07/08/2020] [Indexed: 06/11/2023]
Abstract
How paddy cultivation influences the adsorption isotherms, envelopes, and the kinetics of hexavalent chromate (Cr(VI)) on Fe (hydro)oxide-rich paddy soil, as well as the mechanisms involved, remain largely unaddressed. To this end, the Cr(VI) adsorption characteristics on a paddy soil, in comparison with its parent upland Oxisol, were studied. The results showed that Cr(VI) adsorption capacities (Qmad) were higher in the surface Oxisol than in the same layer of paddy soil. The Qmad increased by 18.0% and 41.3% after removal of soil organic matter (SOM) from the surface Oxisol and paddy soil layers, respectively, indicating that Cr(VI) adsorption was considerably inhibited by SOM. The adsorption and desorption isotherms demonstrated that non-electrostatic adsorption was mainly responsible for Cr(VI) adsorption, accounting for 59.37%-83.42% of Cr(VI) adsorption capacities. The negative shift of the zeta potential-pH curves with Cr(VI) loading further corroborated the finding that non-electrostatic adsorption is largely responsible for Cr(VI) retention. Cr(VI) adsorption at equilibrium, obtained by the stirred flow chamber technique, and the free Fe (hydro)oxides (Fed) contents were in the same order, suggesting that Fed are the main adsorbents for Cr(VI). Therefore, paddy cultivation has had a profound impact on the electrochemical properties of the Oxisol and on subsequent Cr(VI) adsorption characteristics.
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Affiliation(s)
- Hui Hua
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, P. O. Box, 821, Nanjing, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Zhenjie Zhao
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, P. O. Box, 821, Nanjing, China
| | - Renkou Xu
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, P. O. Box, 821, Nanjing, China
| | - E Chang
- Institute of Information Science and Technology, Southeast University, Nanjing 210096, China
| | - Di Fang
- College of Resources and Environmental Sciences, Nanjing Agriculture University, Nanjing, 210095, China
| | - Ying Dong
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, P. O. Box, 821, Nanjing, China
| | - Zhineng Hong
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, P. O. Box, 821, Nanjing, China
| | - Renyong Shi
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, P. O. Box, 821, Nanjing, China
| | - Jun Jiang
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, P. O. Box, 821, Nanjing, China.
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25
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Fluorinated Surfactant Adsorption on Mineral Surfaces: Implications for PFAS Fate and Transport in the Environment. SURFACES 2020. [DOI: 10.3390/surfaces3040037] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Fluorinated surfactants, which fall under the class of per- and polyfluoroalkyl substances (PFAS), are amphiphilic molecules that comprise hydrophobic fluorocarbon chains and hydrophilic head-groups. Fluorinated surfactants have been utilized in many applications, e.g., fire-fighting foams, paints, household/kitchenware items, product packaging, and fabrics. These compounds then made their way into the environment, and have been detected in soil, fresh water, and seawater. From there, they can enter human bodies. Fluorinated surfactants are persistent in water and soil environments, and their adsorption onto mineral surfaces contributes to this persistence. This review examines how fluorinated surfactants adsorb onto mineral surfaces, by analyzing the thermodynamics and kinetics of adsorption, and the underlying mechanisms. Adsorption of fluorinated surfactants onto mineral surfaces can be explained by electrostatic interactions, hydrophobic interactions, hydrogen bonding, and ligand and ion exchange. The aqueous pH, varying salt or humic acid concentrations, and the surfactant chemistry can influence the adsorption of fluorinated surfactants onto mineral surfaces. Further research is needed on fluorinated surfactant adsorbent materials to treat drinking water, and on strategies that can modulate the fate of these compounds in specific environmental locations.
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26
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Hou D, Bolan NS, Tsang DCW, Kirkham MB, O'Connor D. Sustainable soil use and management: An interdisciplinary and systematic approach. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 729:138961. [PMID: 32353725 PMCID: PMC7182530 DOI: 10.1016/j.scitotenv.2020.138961] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2020] [Revised: 04/22/2020] [Accepted: 04/22/2020] [Indexed: 05/06/2023]
Abstract
Soil is a key component of Earth's critical zone. It provides essential services for agricultural production, plant growth, animal habitation, biodiversity, carbon sequestration and environmental quality, which are crucial for achieving the United Nations' Sustainable Development Goals (SDGs). However, soil degradation has occurred in many places throughout the world due to factors such as soil pollution, erosion, salinization, and acidification. In order to achieve the SDGs by the target date of 2030, soils may need to be used and managed in a manner that is more sustainable than is currently practiced. Here we show that research in the field of sustainable soil use and management should prioritize the multifunctional value of soil health and address interdisciplinary linkages with major issues such as biodiversity and climate change. As soil is the largest terrestrial carbon pool, as well as a significant contributor of greenhouse gases, much progress can be made toward curtailing the climate crisis by sustainable soil management practices. One identified option is to increase soil organic carbon levels, especially with recalcitrant forms of carbon (e.g., biochar application). In general, soil health is primarily determined by the actions of the farming community. Therefore, information management and knowledge sharing are necessary to improve the sustainable behavior of practitioners and end-users. Scientists and policy makers are important actors in this social learning process, not only to disseminate evidence-based scientific knowledge, but also in generating new knowledge in close collaboration with farmers. While governmental funding for soil data collection has been generally decreasing, newly available 5G telecommunications, big data and machine learning based data collection and analytical tools are maturing. Interdisciplinary studies that incorporate such advances may lead to the formation of innovative sustainable soil use and management strategies that are aimed toward optimizing soil health and achieving the SDGs.
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Affiliation(s)
- Deyi Hou
- School of Environment, Tsinghua University, Beijing 100084, China.
| | - Nanthi S Bolan
- Global Centre for Environmental Remediation, The University of Newcastle, Callaghan, NSW 2308, Australia
| | - Daniel C W Tsang
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China
| | - Mary B Kirkham
- Department of Agronomy, Throckmorton Plant Sciences Center, Kansas State University, Manhattan, KS, United States
| | - David O'Connor
- School of Environment, Tsinghua University, Beijing 100084, China
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27
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Ji B, Kang P, Wei T, Zhao Y. Challenges of aqueous per- and polyfluoroalkyl substances (PFASs) and their foreseeable removal strategies. CHEMOSPHERE 2020; 250:126316. [PMID: 32120153 DOI: 10.1016/j.chemosphere.2020.126316] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2019] [Revised: 02/21/2020] [Accepted: 02/22/2020] [Indexed: 06/10/2023]
Abstract
Per- and polyfluoroalkyl substances (PFASs) are artificial refractory organic pollutants which are widely presented in aqueous environment. Due to the unquiet strength of the highly polarized carbon-fluorine bond (C-F) and their hydrophobic/lipophobic feature as well as biological persistence properties, the remediation and treatment of PFASs is a big challenge. Preliminary studies indicate that a few kinds of technical approaches could remove or transfer PFASs, but the effectiveness is not high as expected or limited while most of the techniques are only tested at laboratory scale. A review of existing treatment technologies was thus conducted for the purpose to outlook these technologies, and more importantly, to propose the foreseeable technique. As such, a constructed wetland-microbial fuel cell (CW-MFC) technology was recommended, which is a newly emerged technology by integrating physical, chemical and enhanced biological processes plus the wetland plants function with strong eco-friendly feature for a comprehensive removal of PFASs. It is expected that the review can strengthen our understanding on PFASs' research and thus can help selecting reasonable technical means of aqueous PFASs control.
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Affiliation(s)
- Bin Ji
- State Key Laboratory of Eco-Hydraulics in Northwest Arid Region, Xi'an University of Technology, Xi'an, China
| | - Peiying Kang
- State Key Laboratory of Eco-Hydraulics in Northwest Arid Region, Xi'an University of Technology, Xi'an, China
| | - Ting Wei
- State Key Laboratory of Eco-Hydraulics in Northwest Arid Region, Xi'an University of Technology, Xi'an, China
| | - Yaqian Zhao
- State Key Laboratory of Eco-Hydraulics in Northwest Arid Region, Xi'an University of Technology, Xi'an, China.
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28
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Lv K, Gao W, Meng L, Xue Q, Tian H, Wang Y, Jiang G. Phototransformation of perfluorooctane sulfonamide on natural clay minerals: A likely source of short chain perfluorocarboxylic acids. JOURNAL OF HAZARDOUS MATERIALS 2020; 392:122354. [PMID: 32097861 DOI: 10.1016/j.jhazmat.2020.122354] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Revised: 02/02/2020] [Accepted: 02/18/2020] [Indexed: 06/10/2023]
Abstract
In this study, a new phototransformation pathway for perfluorooctane sulfonamide (FOSA) and underlying degradation mechanisms are described. Phototransformation of FOSA in a natural clay mineral (montmorillonite) suspension was compared to that in an aqueous solution. Results showed that the presence of montmorillonite can significantly promote the transformation of FOSA to perfluocarboxylic acids (increasing rate). The phototransformation reaction was found to be initiated by the activation of adsorbed oxygen molecules on the surface of montmorillonite, which generate superoxide anion and hydroxyl radicals. Hydroxyl radicals can then attack FOSA adsorbed onto the surface of montmorillonite, promoting the transformation process. In this reaction, clay minerals played a dual role: providing hydroxyl radicals and concentrating FOSA on their surfaces. This helped to promote the contact and reaction between FOSA and hydroxyl radicals. This study provides the first evidence that heterogeneous oxidation of FOSA at the surface of natural clay minerals may act as an important source of perfluocarboxylic acids (PFCAs), especially short chain PFCAs (i.e. trifluoroacetic acid, TFA).
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Affiliation(s)
- Kun Lv
- Environment Research Institute, Shandong University, Qingdao, 266237, China; State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China
| | - Wei Gao
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China
| | - Lingyi Meng
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Qiao Xue
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China
| | - Haoting Tian
- Shandong Provincial Key Laboratory of Water and Soil Conservation and Environmental Protection, College of Resource and Environment, Linyi University, Linyi, 276005, China.
| | - Yawei Wang
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China.
| | - Guibin Jiang
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China
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29
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Askeland M, Clarke BO, Cheema SA, Mendez A, Gasco G, Paz-Ferreiro J. Biochar sorption of PFOS, PFOA, PFHxS and PFHxA in two soils with contrasting texture. CHEMOSPHERE 2020; 249:126072. [PMID: 32045751 DOI: 10.1016/j.chemosphere.2020.126072] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Revised: 01/28/2020] [Accepted: 01/29/2020] [Indexed: 06/10/2023]
Abstract
The ability to immobilise PFAS in soil may be an essential interim tool while technologies are developed for effective long-term treatment of PFAS contaminated soils. Serial sorption experiments were undertaken using a pine derived biochar produced at 750 °C (P750). All experiments were carried out either in individual mode (solution with one PFAS at 5 μg/L) or mix mode (solution with 5 μg/L of each: PFOS, PFOA, PFHxS and PFHxA), and carried out in 2:1 water to soil solutions. Soils had biochar added in the range 0-5% w/w. Kinetic data were fitted to the pseudo-second order model for both amended soils, with equilibrium times ranging 0.5-96 h for all congeners. PFOS sorption was 11.1 ± 4.5% in the loamy sand compared to 69.8 ± 4.9% in the sandy clay loam. While total sorption was higher in the unamended loamy sand than sandy clay loam for PFHxA, PFOA and PFOS, the effect of biochar amendment for each compound was found to be significantly higher in amended sandy clay loam than in amended loamy sand. Application of biochar reduced the desorbed PFAS fraction of all soils. Soil type and experimental mode played a significant role in influencing desorption. Overall, the relationship between sorbent and congener was demonstrated to be highly impacted by soil type, however the unique physiochemical properties of each PFAS congener greatly influenced its unique equilibrium, sorption and desorption behaviour for each amended soil and mode tested.
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Affiliation(s)
- Matthew Askeland
- School of Engineering, RMIT University, Melbourne, 3000, Australia
| | - Bradley O Clarke
- School of Chemistry, University of Melbourne, Victoria, 3010, Australia
| | - Sardar Alam Cheema
- Department of Agronomy, Faculty of Agriculture, University of Agriculture, Faisalabad, 38040, Pakistan
| | - Ana Mendez
- Department of Geological and Mining Engineering, Technical University of Madrid, 28040, Madrid, Spain
| | - Gabriel Gasco
- Department of Agricultural Production, Technical University of Madrid, Ciudad Universitaria, 28040, Madrid, Spain
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30
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Oliver DP, Li Y, Orr R, Nelson P, Barnes M, McLaughlin MJ, Kookana RS. Sorption behaviour of per- and polyfluoroalkyl substances (PFASs) in tropical soils. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2020; 258:113726. [PMID: 32006795 DOI: 10.1016/j.envpol.2019.113726] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Revised: 11/12/2019] [Accepted: 12/03/2019] [Indexed: 06/10/2023]
Abstract
The sorption behaviour of three perfluoroalkyl substances (PFASs), namely perfluorooctane sulfonic acid (PFOS), perfluorooctanoic acid (PFOA) and perfluorohexane sulfonic acid (PFHxS), was determined on 28 tropical soils. Tropical soils are often highly weathered, richer in sesquioxides than temperate soils and may contain variable charge minerals. There are little data on sorption of PFASs in tropical soils. The highest Kd values were found for PFOS with mean values ranging from 0 to 31.6 L/kg. The Kd values for PFOA and PFHxS ranged from 0 to 4.9 L/kg and from 0 to 5.6 L/kg, respectively. While these values are in the range of literature sorption data, the average Kd values for PFOS and PFOA from the literature were 3.7 times and 3.6 times higher, respectively, than those measured in this study. Stepwise regression analysis did explain some of the variance, but with different explanatory variables for the different PFASs. The main soil properties explaining sorption for PFOS and PFOA were oxalate-extractable Al and pH, and for PFHxS was pH.
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Affiliation(s)
- Danielle P Oliver
- CSIRO Land and Water, Locked Bag 2, Glen Osmond, 5064, South Australia, Australia.
| | - Yasong Li
- CSIRO Land and Water, Locked Bag 2, Glen Osmond, 5064, South Australia, Australia.
| | - Ryan Orr
- College of Science and Engineering, James Cook University, Cairns, 4878, Qld, Australia.
| | - Paul Nelson
- College of Science and Engineering, James Cook University, Cairns, 4878, Qld, Australia.
| | - Mary Barnes
- Centre for Epidemiology and Biostatistics, Flinders University, Adelaide, SA, 5001, Australia.
| | - Michael J McLaughlin
- Soil Science, Waite Research Institute, University of Adelaide, Glen Osmond, 5064, South Australia, Australia.
| | - Rai S Kookana
- CSIRO Land and Water, Locked Bag 2, Glen Osmond, 5064, South Australia, Australia; Soil Science, Waite Research Institute, University of Adelaide, Glen Osmond, 5064, South Australia, Australia.
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Cai Y, Chen H, Yuan R, Wang F, Chen Z, Zhou B. Toxicity of perfluorinated compounds to soil microbial activity: Effect of carbon chain length, functional group and soil properties. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 690:1162-1169. [PMID: 31470479 DOI: 10.1016/j.scitotenv.2019.06.440] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2019] [Revised: 06/26/2019] [Accepted: 06/26/2019] [Indexed: 06/10/2023]
Abstract
Perfluorinated compounds (PFCs) have been detected at various concentrations in different environment compartments due to their widespread usage. Nowadays, soil environment has become a prominent sink of PFCs from surface runoff and penetration, but few researches have been conducted in the toxicity of PFCs to soil microorganisms. To address the issue, microcalorimetry was applied to investigate the toxicity of six PFCs with different carbon chain length (4, 8, and 10) and functional group (carboxylic and sulfonic) to microbial activities in three Chinese soils varying widely in soil properties. Adsorption of PFCs by soil matrix was a key factor in controlling the toxicity of PFCs to soil microorganisms. The differences of carbon chain length and functional groups of PFCs have different impacts on soil microbial activity while affecting adsorption progress. Particularly, the sulfonic PFCs expressed higher toxicity than the carboxylic. It is also identified that the longer the chain length, the greater the toxicity of PFCs. Soil pH was another relevant factor of soil adsorption, and with the increase of pH, adsorption capability increased. Soil available P, N and K were essential nutrients in soil, and suggested to improve microbial activity under PFCs stress.
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Affiliation(s)
- Yanping Cai
- Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China
| | - Huilun Chen
- Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China.
| | - Rongfang Yuan
- Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China
| | - Fei Wang
- Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China
| | - Zhongbing Chen
- Faculty of Environmental Sciences, Czech University of Life Sciences Prague, Kamýcká 129, 16500 Prague, Czech Republic
| | - Beihai Zhou
- Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China.
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Knight ER, Janik LJ, Navarro DA, Kookana RS, McLaughlin MJ. Predicting partitioning of radiolabelled 14C-PFOA in a range of soils using diffuse reflectance infrared spectroscopy. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 686:505-513. [PMID: 31185399 DOI: 10.1016/j.scitotenv.2019.05.339] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Revised: 05/19/2019] [Accepted: 05/22/2019] [Indexed: 06/09/2023]
Abstract
The aim of this study was to establish partitioning coefficients (Kd) of perfluorooctanoic acid (PFOA) in a wide range of soils and determine if those values can be predicted from soil properties using multiple linear regression (MLR) and from infrared spectra of soils using partial least squares regression (PLSR). For 100 different soils, the Kd values of spiked radiolabelled 14C-PFOA ranged from 0.6 to 14.8 L/kg and significantly decreased with soil depth (p < 0.05) due to soil properties that change with depth. The MLR modelling revealed that PFOA sorption was significantly (p < 0.05) influenced, in decreasing order, by organic carbon (OC) content, silt-plus-clay content and soil pH. Soils were partitioned into all soils and surface soils alone. The MLR models using OC, silt-plus-clay content and pH together explained most of the variation in sorption in all soils as well as surface soils alone (0-15 cm). However, correlations between soil properties and Kd values in some soils could not be explained by the MLR model. Modelling of Kd prediction in soils with PLSR and diffuse reflectance (mid) infrared Fourier transform spectroscopy (DRIFT) showed comparable success in explaining the predictions of Kd values, including some of the outliers identified in the MLR model. The PLSR loading weights suggested that quartz, and possibly pyrophyllite minerals, were inversely correlated with the Kd values. Given that MLR requires a-priori characterisation of a range of soil properties and PLSR-DRIFT is a method based on the direct relationship between spectra and soil components, mid-infrared spectroscopy may be a more economical and rapid technique to predict the solid-liquid partitioning of PFOA in soils.
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Affiliation(s)
- Emma R Knight
- School of Agriculture, Food and Wine, The University of Adelaide, PMB 1, Glen Osmond, SA, 5064, Australia; CSIRO Land and Water, PMB 2, Glen Osmond, SA 5064, Australia.
| | - Leslie J Janik
- School of Agriculture, Food and Wine, The University of Adelaide, PMB 1, Glen Osmond, SA, 5064, Australia; CSIRO Land and Water, PMB 2, Glen Osmond, SA 5064, Australia.
| | - Divina A Navarro
- School of Agriculture, Food and Wine, The University of Adelaide, PMB 1, Glen Osmond, SA, 5064, Australia; CSIRO Land and Water, PMB 2, Glen Osmond, SA 5064, Australia.
| | - Rai S Kookana
- School of Agriculture, Food and Wine, The University of Adelaide, PMB 1, Glen Osmond, SA, 5064, Australia; CSIRO Land and Water, PMB 2, Glen Osmond, SA 5064, Australia.
| | - Michael J McLaughlin
- School of Agriculture, Food and Wine, The University of Adelaide, PMB 1, Glen Osmond, SA, 5064, Australia.
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