1
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Tonnis K, Kasting GB, Jaworska J. Impact of solvent dry down, phase change, vehicle pH and slowly reversible keratin binding on skin penetration of cosmetic relevant compounds: II. Solids. Int J Pharm 2024; 661:124451. [PMID: 38992735 DOI: 10.1016/j.ijpharm.2024.124451] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2024] [Revised: 06/11/2024] [Accepted: 07/07/2024] [Indexed: 07/13/2024]
Abstract
We extended a mechanistic, physics-based framework of the dry down process, previously developed for liquids and electrolytes, to solids and coded it into the latest UB/UC/P&G skin permeation model, herein renamed DigiSkin. The framework accounts for the phase change of the permeant from dissolved in a solvent (liquid) to precipitated on the skin surface (solid). The evaporation rate for the solid is reduced due to lower vapor pressure for the solid state versus subcooled liquid. These vapor pressures may differ by two orders of magnitude. The solid may gradually redissolve and penetrate the skin. The framework was tested by simulating the in vitro human skin permeation of the 38 cosmetically relevant solid compounds reported by Hewitt et al., J. Appl. Toxicol. 2019, 1-13. The more detailed handling of the evaporation process greatly improved DigiSkin evaporation predictions (r2 = 0.89). Further, we developed a model reliability prediction score classification using diverse protein reactivity data and identified that 15 of 38 compounds are out of model scope. Dermal delivery predictions for the remaining chemicals have excellent agreement with experimental data. The analysis highlighted the sensitivity of water solubility and equilibrium vapor pressure values on the DigiSkin predictions outcomes influencing agreement with the experimental observations.
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Affiliation(s)
- Kevin Tonnis
- College of Engineering and Applied Science, The University of Cincinnati, Cincinnati, OH 45221, USA
| | - Gerald B Kasting
- The James L. Winkle College of Pharmacy, The University of Cincinnati, Cincinnati, OH 45267-0514, USA
| | - Joanna Jaworska
- The Procter & Gamble Company, Discovery Innovation Platforms, Brussels Innovation Center, Belgium.
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2
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Zhang M, Suuberg EM. Estimation of vapor pressures of perfluoroalkyl substances (PFAS) using COSMOtherm. JOURNAL OF HAZARDOUS MATERIALS 2023; 443:130185. [PMID: 36274547 DOI: 10.1016/j.jhazmat.2022.130185] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Revised: 09/17/2022] [Accepted: 10/11/2022] [Indexed: 06/16/2023]
Abstract
The widespread presence of per- and polyfluoroalkyl substances (PFAS) in the environment and a recognition of their possible health effects has, over the past decade, raised public concerns and led to much new research on these materials. In this field, with so many compounds of potential interest or concern, measuring the physical properties of even a small fraction of these compounds is a formidable task. The research community has turned to use of computational methods to begin to predict many useful properties, based just upon the structure of the compound. In this work, a quantum chemistry computational method (COSMO-RS) has been applied for exploring the possibility and accuracy of PFAS compound property estimation. The vapor pressures and boiling points of eleven PFAS are calculated with COSMOtherm and compared with available experimental data and literature calculation data using other packages. In the meantime, these measured results have permitted evaluation of this popular property estimation technique, which has not yet been fully validated for this class of compounds.
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Affiliation(s)
- Mengke Zhang
- School of Engineering, Brown University, Providence, RI 02912, United States.
| | - Eric M Suuberg
- School of Engineering, Brown University, Providence, RI 02912, United States.
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3
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Zhang M, Yamada K, Bourguet S, Guelfo J, Suuberg EM. Vapor pressure of nine perfluoroalkyl substances (PFASs) determined using the Knudsen Effusion Method. JOURNAL OF CHEMICAL AND ENGINEERING DATA 2020; 65:2332-2342. [PMID: 32968326 PMCID: PMC7505237 DOI: 10.1021/acs.jced.9b00922] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Sublimation vapor pressures of nine pure perfluoroalkyl substances, including Ammonium perfluoro(2-methyl-3-oxahexanoate) (GenX), 1H,1H,2H,2H-Perfluoro-1-decanol (8:2 FTOH), 1H,1H,2H,2H-Perfluoro-1-dodecanol (10:2 FTOH) and C6 to C11 perfluorocarboxylic acids (PFCAs), were measured using the Knudsen technique at near ambient temperatures. Melting temperatures and fusion enthalpies of these compounds were also measured using differential scanning calorimetry. The vapor pressure of GenX ammonium salt is comparable to that of the much higher molecular weight perfluoroundecanoic acid. GenX ammonium salt also did not show actual melting behavior but instead decomposed at around 470 K. The measured near ambient temperature sublimation vapor pressures of the PFCAs and FTOHs were compared with some earlier reported liquid phase vapor pressures obtained at higher temperatures, and reasonable agreement exists between the data obtained in the different studies. The sublimation enthalpies of the PFCAs indicate that the contribution to the sublimation enthalpy of the CF2 group in the alkyl chain is comparable to that of the CH2 group in the corresponding non-fluorinated analogues, even though the PFCAs show consistently higher vapor pressures than do the corresponding carbon number alkanoic acids.
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4
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Eichler CMA, Little JC. A framework to model exposure to per- and polyfluoroalkyl substances in indoor environments. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2020; 22:500-511. [PMID: 32141451 DOI: 10.1039/c9em00556k] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Per- and polyfluoroalkyl substances (PFAS) include a wide range of halogenated chemicals, which have been used as water- and stain-resistant coatings for consumer products and industrial purposes. PFAS are persistent in the environment and several are bioaccumulative, and thus relevant for human and environmental health. Given their pervasiveness, we need to understand how we are exposed to PFAS, especially in indoor environments where many people spend most of their time. Research on indoor exposure to semivolatile organic compounds (SVOCs) has progressed rapidly in recent years. Because many PFAS can be considered SVOCs, much of what has been learned about SVOCs may be used to guide research on PFAS exposure in indoor environments. Here, we briefly review what has been done to assess indoor exposure to PFAS. Then, we propose a systematic indoor exposure framework for PFAS based on methods to estimate exposure to SVOCs. We illustrate how critical parameters such as partition coefficients for different media (particles, dust, surfaces, and clothing) for different types of PFAS could be measured, how these measurements can be used in exposure models for PFAS, and how fundamental, predictive relationships might be used to estimate necessary parameters for emerging compounds.
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Affiliation(s)
- Clara M A Eichler
- Department of Environmental Sciences and Engineering, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
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5
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Affiliation(s)
| | - Chloe Luyet
- Department of Chemical Engineering and Materials Science, Wayne State University, Detroit, MI, USA
| | - Jeffrey J. Potoff
- Department of Chemical Engineering and Materials Science, Wayne State University, Detroit, MI, USA
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6
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Sammut G, Sinagra E, Helmus R, de Voogt P. Perfluoroalkyl substances in the Maltese environment - (I) surface water and rain water. THE SCIENCE OF THE TOTAL ENVIRONMENT 2017; 589:182-190. [PMID: 28259432 DOI: 10.1016/j.scitotenv.2017.02.128] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2016] [Revised: 02/15/2017] [Accepted: 02/15/2017] [Indexed: 05/28/2023]
Abstract
The presence of perfluoroalkyl substances (PFASs) in rain water on the Maltese Islands is reported here for the first time and an extensive survey of these substances in surface water also reported. The Maltese archipelago lies at the centre of the Mediterranean Sea and consists of three main inhabited islands: Malta, Gozo and Comino. Surface water was collected from 41 valleys during the months of February and March 2015 at the peak of the wet season. Rain water was collected during the months of December 2014, February, August, September and October 2015. PFASs were extracted from the water samples using solid phase extraction and the extracts were then analysed using ultra performance liquid chromatography coupled to mass spectrometry in tandem (UPLC-MS/MS). All surface and rain water samples were contaminated with at least one PFAS. PFOS (<LOD - 8.6ng/L) and PFOA (ND - 16ng/L) were the two major PFASs being detected in 100% and 95% of the surface waters respectively. The ΣPFAS concentrations in rain water ranged between 0.38ng/L (1st October 2015) and 6ng/L (21st February 2015). The Maltese archipelago is surrounded by sea and disconnected from any other mainland; therefore the results confirm that remote environments can become contaminated by PFASs from rain events depending on wind prevailing trajectories.
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Affiliation(s)
- G Sammut
- Department of Chemistry, University of Malta, Malta
| | - E Sinagra
- Department of Chemistry, University of Malta, Malta.
| | - R Helmus
- IBED, University of Amsterdam, Amsterdam, Netherlands
| | - P de Voogt
- IBED, University of Amsterdam, Amsterdam, Netherlands; KWR, Watercycle Research Institute, Nieuwegein, Netherlands
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7
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Washington JW, Jenkins TM. Abiotic Hydrolysis of Fluorotelomer-Based Polymers as a Source of Perfluorocarboxylates at the Global Scale. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2015; 49:14129-35. [PMID: 26526296 DOI: 10.1021/acs.est.5b03686] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Fluorotelomer-based polymers (FTPs) are the main product of the fluorotelomer industry. For nearly 10 years, whether FTPs degrade to form perfluorooctanoate (PFOA) and perfluorocarboxylate (PFCA) homologues has been vigorously contested. Here we show that circum-neutral abiotic hydrolysis of a commercial FTP proceeds with half-life estimates of 55-89 years and that base-mediated hydrolysis overtakes neutral hydrolysis at about pH = 10, with a half-life of ~0.7 years at pH ∼ 12. Considered in light of the large production volume of FTPs and the poor efficacy of conventional treatments for recovery of PFCAs from waste streams, these results suggest that FTPs manufactured to date potentially could increase PFCAs 4- to 8-fold over current oceanic loads, largely depending on the integrity of disposal units to contain PFCAs upon hydrolytic generation from FTPs.
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Affiliation(s)
- John W Washington
- USEPA , National Exposure Research Laboratory, 960 College Station Road, Athens, Georgia 30605-2700, United States
| | - Thomas M Jenkins
- USEPA , Senior Environmental Employment Program, Athens, Georgia 30605-2700, United States
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Liu X, Guo Z, Folk EE, Roache NF. Determination of fluorotelomer alcohols in selected consumer products and preliminary investigation of their fate in the indoor environment. CHEMOSPHERE 2015; 129:81-6. [PMID: 24997516 DOI: 10.1016/j.chemosphere.2014.06.012] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2014] [Revised: 06/02/2014] [Accepted: 06/05/2014] [Indexed: 05/21/2023]
Abstract
The U.S. Environmental Protection Agency (EPA) has established an ongoing effort to identify the major perfluorocarboxylic acid (PFCA) sources in nonoccupational indoor environments and characterize their transport and fate. This study determined the concentrations of fluorotelomer alcohols (FTOHs), which are the precursors to PFCAs, in fifty-four consumer products collected from the U.S. open market in the years of 2011 and 2013. The products included carpet, commercial carpet-care liquids, household carpet/fabric-care liquids, treated apparel, treated home textiles, treated non-woven medical garments, floor waxes, food-contact paper, membranes for apparel, and thread-sealant tapes. The FTOHs quantified were 1H,1H,2H,2H-perfluoro-1-octanol (6:2 FTOH), 1H,1H,2H,2H-perfluoro-1-decanol (8:2 FTOH), and 1H,1H,2H,2H-perfluoro-1-dodecanol (10:2 FTOH). The content of 6:2 FTOH ranged from non-delectable to 331μgg(-1), 8:2 FTOH from non-delectable to 92μgg(-1), and 10:2 FTOH from non-detectable to 24μgg(-1). In addition, two consumer products from the home textile category were tested in the washing-drying process. One product from the treated apparel category and one from the home textile category were tested in the micro-scale chamber under elevated temperatures. The experimental data show that the washing-drying process with one cycle did not significantly reduce the FTOH concentrations in the tested consumer products. FTOH off-gassing was observed under accelerated aging conditions. Future tests should include air sampling to allow determination of the absolute emission rates at different temperatures. The results of this study should be informative to exposure assessment and risk management.
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Affiliation(s)
- Xiaoyu Liu
- U.S. Environmental Protection Agency, Office of Research and Development, National Risk Management Research Laboratory, Research Triangle Park, NC 27711, United States.
| | - Zhishi Guo
- U.S. Environmental Protection Agency, Office of Research and Development, National Risk Management Research Laboratory, Research Triangle Park, NC 27711, United States
| | - Edgar E Folk
- ARCADIS U.S., Inc., 4915 Prospectus Drive, Suite F, Durham, NC 27713, United States
| | - Nancy F Roache
- ARCADIS U.S., Inc., 4915 Prospectus Drive, Suite F, Durham, NC 27713, United States
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9
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Kim M, Li LY, Grace JR, Yue C. Selecting reliable physicochemical properties of perfluoroalkyl and polyfluoroalkyl substances (PFASs) based on molecular descriptors. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2015; 196:462-72. [PMID: 25467694 DOI: 10.1016/j.envpol.2014.11.008] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2014] [Revised: 10/31/2014] [Accepted: 11/03/2014] [Indexed: 05/28/2023]
Abstract
Perfluoroalkyl and polyfluoroalkyl substances (PFASs) are a class of global environmental pollutants whose environmental fate and adverse effects are of concern. However, data on the basic physicochemical properties of PFASs are scarce. To fill part of the data gaps, improved quantitative structure -property relationship (QSPR) models for prediction of PFAS properties are developed based on the correlation between reported experimental data and molecular descriptors (fluorine number, molar volume and total surface area). Properties include vapor pressure, aqueous solubility, octanol/water partition coefficient, air/water partition coefficient and octanol/air partition coefficient. The fluorine number-descriptor model is based on good statistical results. However, this model cannot distinguish among PFASs with the same number of attached fluorines. Setting aside the fluorine number-descriptor models, models based on molar volume are statistically better than those based on total surface area.Therefore, The PFAS data obtained from the molar volume descriptor model are more reliable than from fluorine number and total surface area descriptor models. These results are intended to improve the understanding of the behavior and fate of PFASs in the environment, at contaminated sites and during remediation.
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Affiliation(s)
- Minhee Kim
- Department of Civil Engineering, University of British Columbia, 6250 Applied Science Lane, Vancouver, BC, Canada V6T 1Z4
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10
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11
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Rahman MF, Peldszus S, Anderson WB. Behaviour and fate of perfluoroalkyl and polyfluoroalkyl substances (PFASs) in drinking water treatment: a review. WATER RESEARCH 2014; 50:318-40. [PMID: 24216232 DOI: 10.1016/j.watres.2013.10.045] [Citation(s) in RCA: 410] [Impact Index Per Article: 41.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2013] [Revised: 10/04/2013] [Accepted: 10/16/2013] [Indexed: 05/08/2023]
Abstract
This article reviews perfluoroalkyl and polyfluoroalkyl substance (PFAS) characteristics, their occurrence in surface water, and their fate in drinking water treatment processes. PFASs have been detected globally in the aquatic environment including drinking water at trace concentrations and due, in part, to their persistence in human tissue some are being investigated for regulation. They are aliphatic compounds containing saturated carbon-fluorine bonds and are resistant to chemical, physical, and biological degradation. Functional groups, carbon chain length, and hydrophilicity/hydrophobicity are some of the important structural properties of PFASs that affect their fate during drinking water treatment. Full-scale drinking water treatment plant occurrence data indicate that PFASs, if present in raw water, are not substantially removed by most drinking water treatment processes including coagulation, flocculation, sedimentation, filtration, biofiltration, oxidation (chlorination, ozonation, AOPs), UV irradiation, and low pressure membranes. Early observations suggest that activated carbon adsorption, ion exchange, and high pressure membrane filtration may be effective in controlling these contaminants. However, branched isomers and the increasingly used shorter chain PFAS replacement products may be problematic as it pertains to the accurate assessment of PFAS behaviour through drinking water treatment processes since only limited information is available for these PFASs.
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Affiliation(s)
- Mohammad Feisal Rahman
- NSERC Industrial Research Chair in Water Treatment, Department of Civil and Environmental Engineering, University of Waterloo, 200 University Avenue West, Waterloo, Ontario, Canada N2L 3G1.
| | - Sigrid Peldszus
- NSERC Industrial Research Chair in Water Treatment, Department of Civil and Environmental Engineering, University of Waterloo, 200 University Avenue West, Waterloo, Ontario, Canada N2L 3G1
| | - William B Anderson
- NSERC Industrial Research Chair in Water Treatment, Department of Civil and Environmental Engineering, University of Waterloo, 200 University Avenue West, Waterloo, Ontario, Canada N2L 3G1
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12
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Kim IP. Computing boiling temperatures and vapor pressures in homologous series of perfluorinated oligomers. RUSSIAN JOURNAL OF PHYSICAL CHEMISTRY A 2013. [DOI: 10.1134/s0036024413070169] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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13
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Styler SA, Myers AL, Donaldson DJ. Heterogeneous photooxidation of fluorotelomer alcohols: a new source of aerosol-phase perfluorinated carboxylic acids. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2013; 47:6358-6367. [PMID: 23688121 DOI: 10.1021/es4011509] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Little is known of the atmospheric fate(s) of fluorotelomer alcohols (FTOHs), a class of high-production-volume chemicals used in the production of water- and oil-repelling surface coatings and which have been detected in a wide variety of urban and remote environmental matrices. In the present study, we investigated the uptake and photochemistry of FTOHs at the surface of TiO2, Fe2O3, Mauritanian sand, and Icelandic volcanic ash. Gas-phase 3,3,3-trifluoropropanol, 4:2 FTOH, and 6:2 FTOH exhibited significant uptake to each of the surfaces under study. The sand- and ash-catalyzed heterogeneous photooxidation of 6:2 FTOH resulted in the rapid production and subsequent slow degradation of surface-sorbed perfluorinated carboxylic acids (PFCAs). We suggest that this transformation, which proceeds via saturated and unsaturated fluorotelomer carboxylic acid intermediates (6:2 FTCA/FTUCA), is catalyzed by Fe and Ti contained within the samples. These results provide the first evidence that the heterogeneous oxidation of FTOHs at metal-rich atmospheric surfaces may provide a significant loss mechanism for these chemicals and also act as a source of aerosol-phase PFCAs close to source regions. Subsequent long-range transport of these aerosol-sorbed PFCAs has the potential to join oceanic transport and local gas-phase FTOH oxidation as a source of PFCAs to Arctic regions.
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Affiliation(s)
- Sarah A Styler
- Department of Chemistry, University of Toronto, Toronto, Ontario, Canada
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14
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Eibenberger S, Gerlich S, Arndt M, Mayor M, Tüxen J. Matter–wave interference of particles selected from a molecular library with masses exceeding 10 000 amu. Phys Chem Chem Phys 2013; 15:14696-700. [DOI: 10.1039/c3cp51500a] [Citation(s) in RCA: 169] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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15
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Cai M, Xie Z, Möller A, Yin Z, Huang P, Cai M, Yang H, Sturm R, He J, Ebinghaus R. Polyfluorinated compounds in the atmosphere along a cruise pathway from the Japan Sea to the Arctic Ocean. CHEMOSPHERE 2012; 87:989-97. [PMID: 22137357 DOI: 10.1016/j.chemosphere.2011.11.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2011] [Revised: 11/04/2011] [Accepted: 11/06/2011] [Indexed: 05/06/2023]
Abstract
Neutral polyfluorinated alkyl substances (PFASs) were measured in high-volume air samples collected on board the research vessel Snow Dragon during the 4th Chinese National Arctic Expedition from the Japan Sea to the Arctic Ocean in 2010. Four volatile and semi-volatile PFASs (fluorotelomer alcohols (FTOHs), fluorotelomer acids (FTAs), perfluoroalkyl sulfonamides (FASAs), and sulfonamidoethanols (FASEs)) were analyzed respectively in the gas and particle phases. FTOHs were the dominant PFASs in the gas phase (61-358pgm(-3)), followed by FTAs (5.2-47.9pgm(-3)), FASEs (1.9-15.0pgm(-3)), and FASAs (0.5-2.1pgm(-3)). In the particle phase, the dominant PFAS class was FTOHs (1.0-9.9pgm(-3)). The particle-associated fraction followed the general trend of FASEs>FASAs>FTOHs. Compared with other atmospheric PFAS measurements, the ranges of concentrations of ∑FTOH in this study were similar to those reported from Toronto, north America (urban), the northeast Atlantic Ocean, and northern Germany. Significant correlations between FASEs in the gas phase and ambient air temperature indicate that cold surfaces such as sea-ice, snowpack, and surface seawater influence atmospheric FASEs.
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Affiliation(s)
- Minghong Cai
- SOA Key Laboratory for Polar Science, Polar Research Institute of China, Shanghai, China
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16
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Ahrens L, Shoeib M, Harner T, Lane DA, Guo R, Reiner EJ. Comparison of Annular Diffusion Denuder and High Volume Air Samplers for Measuring Per- and Polyfluoroalkyl Substances in the Atmosphere. Anal Chem 2011; 83:9622-8. [DOI: 10.1021/ac202414w] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Lutz Ahrens
- Environment Canada, Science and Technology Branch, Toronto, ON, Canada, M3H 5T4
| | - Mahiba Shoeib
- Environment Canada, Science and Technology Branch, Toronto, ON, Canada, M3H 5T4
| | - Tom Harner
- Environment Canada, Science and Technology Branch, Toronto, ON, Canada, M3H 5T4
| | - Douglas A. Lane
- Environment Canada, Science and Technology Branch, Toronto, ON, Canada, M3H 5T4
| | - Rui Guo
- University of Toronto, Department of Chemistry, Toronto, ON, Canada, M5S 3H6
- Ontario Ministry of the Environment, Toronto, ON, Canada, M9P 3 V6
| | - Eric J. Reiner
- University of Toronto, Department of Chemistry, Toronto, ON, Canada, M5S 3H6
- Ontario Ministry of the Environment, Toronto, ON, Canada, M9P 3 V6
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17
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Kwok KY, Taniyasu S, Yeung LWY, Murphy MB, Lam PKS, Horii Y, Kannan K, Petrick G, Sinha RK, Yamashita N. Flux of perfluorinated chemicals through wet deposition in Japan, the United States, and several other countries. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2010; 44:7043-9. [PMID: 20795671 DOI: 10.1021/es101170c] [Citation(s) in RCA: 92] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
The widespread distribution of perfluorinated chemicals (PFCs) in different environmental matrices has prompted concern about the sources, fate, and transport of these classes of chemicals. PFCs are present in the atmosphere, but only a few studies have investigated their occurrence in precipitation. In this study, concentrations of 20 PFCs, including C3-C5 short-chain PFCs, were quantified using HPLC-MS/MS in precipitation samples from Japan (n = 31), the United States (n = 12), China (n = 5), India (n = 2), and France (n = 2). Among the PFCs measured, perfluoropropanoic acid (PFPrA) was detected in all of the precipitation samples. Average total PFC concentrations ranged from 1.40 to 18.1 ng/L for the seven cities studied. The greatest total PFC concentrations were detected in Tsukuba, Japan, whereas the lowest concentrations were detected in Patna, India. PFPrA, perfluorooctanoic acid (PFOA), and perfluorononanoic acid (PFNA) were found to be the dominant PFCs in Japanese and U.S. precipitation samples. No observable seasonal trend was found in precipitation samples from two locations in Japan. Annual fluxes of PFCs were estimated for Japan and the U.S. and the evidence for precipitation as an effective scavenger of PFCs in the atmosphere is reported.
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Affiliation(s)
- Karen Y Kwok
- State Key Laboratory in Marine Pollution, Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong SAR, China
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18
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Plassmann MM, Berger U. Trace analytical methods for semifluorinated n-alkanes in snow, soil, and air. Anal Chem 2010; 82:4551-7. [PMID: 20446671 DOI: 10.1021/ac1005519] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Semifluorinated n-alkanes (SFAs) are anthropogenic chemicals that are used in ski waxes and, thus, are released directly into the environment, but their subsequent fate and distribution are as yet unknown. Therefore, simple, selective, and sensitive methods were developed for analyzing trace amounts of SFAs in snow/water, soil, and air samples by gas chromatography coupled to electron capture negative ionization mass spectrometry (GC/ECNI-MS). Recoveries were generally in the range of 70-120%, depending on the compound and matrix. The analytical sensitivity was higher for SFAs with longer fluorinated chains, and the instrumental limits of detection ranged from 0.3 to 260 pg injected, providing method detection limits of 0.54-311 ng L(-1), 0.004-9.86 ng g(-1), and 0.4-531 ng m(-3) for snow (analyzed as its meltwater), soil, and air samples, respectively. Using the developed procedures, SFAs were found in snow (meltwater) and soil samples from a small cross-country ski area in Sweden at concentrations up to 1.3 microg L(-1) and 47 pg g(-1), respectively.
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Affiliation(s)
- Merle M Plassmann
- Department of Applied Environmental Science (ITM), Stockholm University, 106 91 Stockholm, Sweden.
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19
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Ruan T, Wang Y, Wang T, Zhang Q, Ding L, Liu J, Wang C, Qu G, Jiang G. Presence and partitioning behavior of polyfluorinated iodine alkanes in environmental matrices around a fluorochemical manufacturing plant: another possible source for perfluorinated carboxylic acids? ENVIRONMENTAL SCIENCE & TECHNOLOGY 2010; 44:5755-5761. [PMID: 20608731 DOI: 10.1021/es101507s] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
The indistinct origins of some ubiquitous perfluorinated alkyl acids have attracted great attention in recent decades. In this present work, even-chained polyfluorinated iodides (PFIs), a group of volatile perfluorinated compounds (PFCs), including four perfluorinated iodine alkanes (FIAs) and three polyfluorinated telomer iodides (FTIs) were confirmed to be present in the environment. A wide concentration range was found for FIAs at 1.41 to 3.08x10(4) pg/L, and for FTIs at 1.39 to 1.32x10(3) pg/L in the ambient air collected around a fluorochemical manufacturing plant in Shandong province, northern China. Whereas for surface soils, most of these PFIs were below detection limits and only small amounts of analytes with higher carbon chain (such as perfluorododecyl iodide and 1H,1H,2H,2H-perfluorodecyl iodide, 16.6-499 pg/g) could be sporadically detected. The presence of the PFIs in different environmental matrices in the investigated area and calculated vapor pressures (0.095-20.4 Torr) verify that they can be considered as volatile organic chemicals and easily be released into the atmosphere. Together with reported degradation ability and long-range transport potential, the identification of these PFIs indicates that unintentional release during the telomer reaction process might also be another route for the formation and distribution of certain polyfluorinated alcohols, aldehydes, and carboxylic acid derivatives under oxidative conditions in the environment.
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Affiliation(s)
- Ting Ruan
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085
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20
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Liu J, Wang N, Buck RC, Wolstenholme BW, Folsom PW, Sulecki LM, Bellin CA. Aerobic biodegradation of [14C] 6:2 fluorotelomer alcohol in a flow-through soil incubation system. CHEMOSPHERE 2010; 80:716-723. [PMID: 20591465 DOI: 10.1016/j.chemosphere.2010.05.027] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2010] [Revised: 05/18/2010] [Accepted: 05/19/2010] [Indexed: 05/27/2023]
Abstract
The aerobic biodegradation of [1,2-(14)C] 6:2 FTOH [F(CF(2))(6)(14)CH(2)(14)CH(2)OH] in a flow-through soil incubation system is described. Soil samples dosed with [1,2-(14)C] 6:2 FTOH were analyzed by liquid scintillation counting, LC/ARC (liquid chromatography/accurate radioisotope counting), LC/MS/MS, and thermal combustion to account for 6:2 FTOH and its transformation products over 84 d. Half of the [1,2-(14)C] 6:2 FTOH disappeared from soil in 1.3 d, undergoing simultaneous microbial degradation and partitioning of volatile transformation product(s) and the 6:2 FTOH precursor into the air phase. The overall (14)C (radioactivity) mass balance in live and sterile treatments was 77-87% over 84-d incubation. In the live test system, 36% of total (14)C dosed was captured in the airflow (headspace), 25% as soil-bound residues recovered via thermal combustion, and 16% as soil extractable. After 84 d, [(14)C] 5:2 sFTOH [F(CF(2))(5)CH(OH)(14)CH(3)] was the dominant transformation product with 16% molar yield and primarily detected in the airflow. The airflow also contained [1,2-(14)C] 6:2 FTOH and (14)CO(2) at 14% and 6% of total (14)C dosed, respectively. The other significant stable transformation products, all detected in soil, were 5:3 acid [F(CF(2))(5)CH(2)CH(2)COOH, 12%], PFHxA [F(CF(2))(5)COOH, 4.5%] and PFPeA [F(CF(2))(4)COOH, 4.2%]. Soil-bound residues as well as conjugates between fluorinated transformation products and dissolved soil components were only observed in the live test system and absent in the sterile soil, suggesting that such binding and complexation are microbially or enzymatically driven processes. At day 84, 5:3 acid is postulated to be the major transformation product in soil-bound residues, which may not be available for further biodegradation in soil environment.
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Affiliation(s)
- Jinxia Liu
- E.I. du Pont De Nemours & Co., Inc, Wilmington, DE, USA.
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21
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Rayne S, Forest K. Perfluoroalkyl sulfonic and carboxylic acids: a critical review of physicochemical properties, levels and patterns in waters and wastewaters, and treatment methods. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART A, TOXIC/HAZARDOUS SUBSTANCES & ENVIRONMENTAL ENGINEERING 2009; 44:1145-1199. [PMID: 19847705 DOI: 10.1080/10934520903139811] [Citation(s) in RCA: 230] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Perfluorinated acids (PFAs) are an emerging class of environmental contaminants present in various environmental and biological matrices. Two major PFA subclasses are the perfluorinated sulfonic acids (PFSAs) and carboxylic acids (PFCAs). The physicochemical properties and partitioning behavior for the linear PFA members are poorly understood and widely debated. Even less is known about the numerous branched congeners with varying perfluoroalkyl chain lengths, leading to confounding issues around attempts to constrain the properties of PFAs. Current computational methods are not adequate for reliable multimedia modeling efforts and risk assessments. These compounds are widely present in surface, ground, marine, and drinking waters at concentrations that vary from pg L(-1) to microg L(-1). Concentration gradients of up to several orders of magnitude are observed in all types of aquatic systems and reflect proximity to known industrial sources concentrated near populated regions. Some wastewaters contain PFAs at mg L(-1) to low g L(-1) levels, or up to 10 orders of magnitude higher than present in more pristine receiving waters. With the exception of trifluoroacetic acid, which is thought to have both significant natural and anthropogenic sources, all PFSAs and PFCAs are believed to arise from human activities. Filtration and sorption technologies offer the most promising existing removal methods for PFAs in aqueous waste streams, although sonochemical approaches hold promise. Additional studies need to be conducted to better define opportunities from evaporative, extractive, thermal, advanced oxidative, direct and catalyzed photochemical, reductive, and biodegradation methods. Most PFA treatment methods exhibit slow kinetic profiles, hindering their direct application in conventional low hydraulic residence time systems.
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Affiliation(s)
- Sierra Rayne
- Department of Chemistry, University of Winnipeg, Winnipeg, Manitoba, Canada.
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22
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Rayne S, Forest K, Friesen KJ. Estimated congener specific gas-phase atmospheric behavior and fractionation of perfluoroalkyl compounds: rates of reaction with atmospheric oxidants, air-water partitioning, and wet/dry deposition lifetimes. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART A, TOXIC/HAZARDOUS SUBSTANCES & ENVIRONMENTAL ENGINEERING 2009; 44:936-954. [PMID: 19827486 DOI: 10.1080/10934520902996815] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
A quantitative structure-activity model has been validated for estimating congener specific gas-phase hydroxyl radical reaction rates for perfluoroalkyl sulfonic acids (PFSAs), carboxylic acids (PFCAs), aldehydes (PFAls) and dihydrates, fluorotelomer olefins (FTOls), alcohols (FTOHs), aldehydes (FTAls), and acids (FTAcs), and sulfonamides (SAs), sulfonamidoethanols (SEs), and sulfonamido carboxylic acids (SAAs), and their alkylated derivatives based on calculated semi-empirical PM6 method ionization potentials. Corresponding gas-phase reaction rates with nitrate radicals and ozone have also been estimated using the computationally derived ionization potentials. Henry's law constants for these classes of perfluorinated compounds also appear to be reasonably approximated by the SPARC software program, thereby allowing estimation of wet and dry atmospheric deposition rates. Both congener specific gas-phase atmospheric and air-water interface fractionation of these compounds is expected, complicating current source apportionment perspectives and necessitating integration of such differential partitioning influences into future multimedia models. The findings will allow development and refinement of more accurate and detailed local through global scale atmospheric models for the atmospheric fate of perfluoroalkyl compounds.
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Affiliation(s)
- Sierra Rayne
- Department of Chemistry, University of Winnipeg, Winnipeg, Manitoba, Canada.
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23
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Analysis of fluorotelomer alcohols in soils: Optimization of extraction and chromatography. J Chromatogr A 2009; 1216:5347-54. [PMID: 19497578 DOI: 10.1016/j.chroma.2009.05.035] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2009] [Revised: 05/11/2009] [Accepted: 05/15/2009] [Indexed: 11/24/2022]
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24
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Kim IP, Kiryukhin DP, Kolesnikova AM, Kuryavyi VG, Bouznik VM. Differential thermogravimetric analysis of the products of radiation-chemical telomerization of tetrafluoroethylene in acetone. HIGH ENERGY CHEMISTRY 2009. [DOI: 10.1134/s0018143909010032] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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25
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van Leeuwen SPJ, de Boer J. Extraction and clean-up strategies for the analysis of poly- and perfluoroalkyl substances in environmental and human matrices. J Chromatogr A 2007; 1153:172-85. [PMID: 17349649 DOI: 10.1016/j.chroma.2007.02.069] [Citation(s) in RCA: 122] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2006] [Revised: 02/13/2007] [Accepted: 02/20/2007] [Indexed: 11/22/2022]
Abstract
The rapidly expanding field of per- and polyfluorinated alkyl substances (PFASs) research has resulted in a wide range of analytical methodologies to determine the human and environmental exposure to PFASs. This paper reviews the currently applied techniques for sample pre-treatment, extraction and clean-up for the analysis of ionic and non-ionic PFASs in human and environmental matrices. Solid phase extraction (SPE) is the method of choice for liquid samples (e.g. water, blood, serum, plasma), and may be automated in an on-line set-up for (large volume) sample enrichment and sample clean-up. Prior to SPE, sample pre-treatment (filtration or centrifugation for water or protein precipitation for blood) may be required. Liquid-liquid extraction can also be used for liquid samples (and does not require above mentioned sample pretreatment). Solid-liquid extraction is the commonly applied method for solid matrices (biota, sludge, soil, sediment), but automation options are limited due to contamination from polytetrafluorethylene tubings and parts applied in extraction equipment. Air is generally preconcentrated on XAD-resins sandwiched between polyurethane foam plugs. Clean-up of crude extracts is essential for destruction and removal of lipids and other co-extractives that may interfere in the instrumental determination. SPE, (fluorous) silica column chromatography, dispersive graphitized carbon and destructive methods such as sulphuric acid or KOH treatment can be applied for clean-up of extracts. Care should be taken to avoid contamination (e.g. from sample bottles, filters, equipment) and losses of PFASs (e.g. adsorption, volatilization) during sampling, extraction and clean-up. Storage at -20 degrees C is generally appropriate for conservation of samples.
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Affiliation(s)
- S P J van Leeuwen
- Institute for Environmental Studies (IVM), Vrije Universiteit, De Boelelaan 1087, 1081 HV Amsterdam, The Netherlands.
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26
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Waterland RL, Dobbs KD. Atmospheric Chemistry of Linear Perfluorinated Aldehydes: Dissociation Kinetics of CnF2n+1CO Radicals. J Phys Chem A 2007; 111:2555-62. [PMID: 17388359 DOI: 10.1021/jp067587+] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Linear perfluorinated aldehydes (PFALs, CnF2n+1CHO) are important intermediate species in the atmospheric oxidation pathway of many polyfluorinated compounds. PFALs can be further oxidized in the gas phase to give perfluorinated carboxylic acids (PFCAs, CnF2n+1C(O)OH, n = 6, 12) which have been detected in animal tissues and at low parts per billion levels in human blood sera. In this paper, we report ab initio quantum chemistry calculations of the decarbonylation kinetics of CnF2n+1CO radicals. Our results show that CnF2n+1CO radicals have a strong tendency to decompose to give CnF2n+1 and CO under atmospheric conditions: the Arrhenius activation energies for decarbonylation of CF3CO, C2F5CO, and C3F7CO obtained using PMP4/6-311++G(2d,p) are 8.8, 6.6, and 5.8 kcal/mol, respectively, each of which is about 5 kcal/mol lower than the barrier for the corresponding nonfluorinated radicals. The lowering of the barrier for decarbonylation of CnF2n+1CO relative to that of CnH2n+1CO is well explained by electron withdrawal by F atoms that serve to weaken the critical C-CO bond. These results have important implications for the atmospheric fate of PFALs and the atmospheric pathways to PFCAs. The main effect of decarbonylation of CnF2n+1CO is to decrease the molar yield of CnF2n+1C(O)OH; if 100% of the CnF2n+1CO decompose, the yield of CnF2n+1C(O)OH must be zero. There is considerable scope for additional experimental and theoretical studies.
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Affiliation(s)
- Robert L Waterland
- DuPont Central Research & Development, Experimental Station, P. O. Box 80320, Wilmington, Delaware 19880-0320, USA.
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27
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Cobranchi DP, Botelho M, Buxton LW, Buck RC, Kaiser MA. Vapor pressure determinations of 8-2 fluorortelomer alcohol and 1-H perfluorooctane by capillary gas chromatography. J Chromatogr A 2006; 1108:248-51. [PMID: 16443234 DOI: 10.1016/j.chroma.2006.01.020] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2005] [Accepted: 01/09/2006] [Indexed: 11/18/2022]
Abstract
Two distinctly different capillary gas chromatographic methods were used to determine the vapor pressure of 8-2 fluorotelomer alcohol (8-2 FTOH) and 1-H perfluoroheptane at several temperatures. For measurements employing the relative retention-time method, a short polymethylsiloxane column was used from 25 to 65 degrees C. For the 8-2 FTOH, hydrocarbon alcohols and perfluoroalcohols were used as reference standards. For 1-H perfluoroheptane, hydrocarbons were used as reference standards. Vapor pressure estimates could differ by as much as an order of magnitude compared to published results determined by other (nonchromatographic) methods. This variance may be a function of solvent-solute interactions within the gas chromatographic column and the infinite dilution assumption, both used in the relative retention method. For comparison, data were also gathered using headspace gas chromatography (GC) with atomic emission detection (AED). The results from this novel GC/AED method were consistent with prior nonchromatographic results. A discussion of why headspace is the preferred technique for the determination of vapor pressure for fluorinated compounds is presented.
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Affiliation(s)
- Daryl P Cobranchi
- DuPont Corporate Center for Analytical Sciences, PO Box 80402, Wilmington, DE 19880-0402, USA
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28
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Waterland R, Hurley M, Misner J, Wallington T, Melo S, Strong K, Dumoulin R, Castera L, Stock N, Mabury S. Gas phase UV and IR absorption spectra of CF3CH2CH2OH and F(CF2CF2)xCH2CH2OH (x=2, 3, 4). J Fluor Chem 2005. [DOI: 10.1016/j.jfluchem.2005.06.010] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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29
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Risikobewertung von Perfluortensiden als Beitrag zur aktuellen Diskussion zum REACH-Dossier der EU-Kommission. ACTA ACUST UNITED AC 2005. [DOI: 10.1007/bf03038694] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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30
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Ellis DA, Denkenberger KA, Burrow TE, Mabury SA. The Use of 19F NMR to Interpret the Structural Properties of Perfluorocarboxylate Acids: A Possible Correlation with Their Environmental Disposition. J Phys Chem A 2004. [DOI: 10.1021/jp049372a] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- David A. Ellis
- Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, ON, Canada M5S 3H6, and Department of Chemistry, 152 Davey Laboratory, The Pennsylvania State University, University Park, Pennsylvania 16802
| | - Kerri A. Denkenberger
- Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, ON, Canada M5S 3H6, and Department of Chemistry, 152 Davey Laboratory, The Pennsylvania State University, University Park, Pennsylvania 16802
| | - Timothy E. Burrow
- Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, ON, Canada M5S 3H6, and Department of Chemistry, 152 Davey Laboratory, The Pennsylvania State University, University Park, Pennsylvania 16802
| | - Scott A. Mabury
- Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, ON, Canada M5S 3H6, and Department of Chemistry, 152 Davey Laboratory, The Pennsylvania State University, University Park, Pennsylvania 16802
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31
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Dinglasan MJA, Ye Y, Edwards EA, Mabury SA. Fluorotelomer alcohol biodegradation yields poly- and perfluorinated acids. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2004; 38:2857-64. [PMID: 15212260 DOI: 10.1021/es0350177] [Citation(s) in RCA: 341] [Impact Index Per Article: 17.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
The widespread detection of environmentally persistent perfluorinated acids (PFCAs) such as perfluorooctanoic acid (PFOA) and its longer chained homologues (C9>C15) in biota has instigated a need to identify potential sources. It has recently been suggested that fluorinated telomer alcohols (FTOHs) are probable precursor compounds that may undergo transformation reactions in the environment leading to the formation of these potentially toxic and bioaccumulative PFCAs. This study examined the aerobic biodegradation of the 8:2 telomer alcohol (8:2 FTOH, CF3(CF2)7CH2CH2OH) using a mixed microbial system. The initial measured half-life of the 8:2 FTOH was approximately 0.2 days mg(-1) of initial biomass protein. The degradation of the telomer alcohol was monitored using a gas chromatograph equipped with an electron capture detector (GC/ECD). Volatile metabolites were identified using gas chromatography/ mass spectrometry (GC/MS), and nonvolatile metabolites were identified and quantified using liquid chromatography/ tandem mass spectrometry (LC/MS/MS). Telomer acids (CF3(CF2)7CH2COOH; CF3(CF2)6CFCHCOOH) and PFOA were identified as metabolites during the degradation, the unsaturated telomer acid being the predominant metabolite measured. The overall mechanism involves the oxidation of the 8:2 FTOH to the telomer acid via the transient telomer aldehyde. The telomer acid via a beta-oxidation mechanism was furthertransformed, leading to the unsaturated acid and ultimately producing the highly stable PFOA. Telomer alcohols were demonstrated to be potential sources of PFCAs as a consequence of biotic degradation. Biological transformation may be a major degradation pathway for fluorinated telomer alcohols in aquatic systems.
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Affiliation(s)
- Mary Joyce A Dinglasan
- Department of Chemistry, University of Toronto, 80 Saint George Street, Toronto, Ontario, Canada M5S 3H6
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32
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Berger U, Langlois I, Oehme M, Kallenborn R. Comparison of three types of mass spectrometers for HPLC/MS analysis of perfluoroalkylated substances and fluorotelomer alcohols. EUROPEAN JOURNAL OF MASS SPECTROMETRY (CHICHESTER, ENGLAND) 2004; 10:579-588. [PMID: 15531790 DOI: 10.1255/ejms.679] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The performance of three different types of mass spectrometers (MS) coupled to high performance liquid chromatography (HPLC) was compared for trace analysis of perfluoroalkylated substances (PFAS) and fluorotelomer alcohols (FTOHs). Ion trap MS in the full scan and product ion MS2 mode, time-of-flight (TOF) high resolution MS and quadrupole MS in the selected ion mode as well as triple quadrupole tandem MS were tested. Electrospray ionisation in the negative ion mode [ESI-] was best suited for all instruments and compounds. PFAS could only be separated by a buffered mobile phase, but the presence of buffer suppressed the ionisation of FTOHs. Therefore, two independent chromatographic methods were developed for the two compound classes. Mass spectra and product ion spectra obtained by in-source and collision induced dissociation fragmentation are discussed including ion adduct formation. Product ion yields of PFAS were only in the range of 0.3 to 12%, independent from the applied MS instrument. Ion trap MS2 gave product ion yields of 20 to 62% for FTOHs, whereas only 4.1 to 5.8% were obtained by triple quadrupole tandem MS. Ion trap MS was best suited for qualitative analysis and structure elucidation of branched isomeric structures of PFAS. Providing typical detection limits of 5 ng injected in MS2 mode, it was not sensitive enough for selective trace amount quantification. TOF high resolution MS was the only technique combining high selectivity and excellent sensitivity for PFAS analysis (detection limits of 2 to 10 pg), but lacked the possibility of MS-MS. Triple quadrupole tandem MS was the method of choice for quantification of FTOHs with detection limits in the low pg range. It is also well suited for the determination of PFAS, though its detection limits of 10 to 100 pg in tandem MS mode are about one order of magnitude higher than for TOF MS.
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Affiliation(s)
- Urs Berger
- Norwegian Institute for Air Research (NILU), Instituttveien 18, NO-2027 Kjeller and The Polar Environmental Centre, NO-9296 Tromsø, Norway.
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