Comprehensive Nontargeted Analysis of Fluorosurfactant Byproducts and Reaction Products in Wastewater from Semiconductor Manufacturing

Comprehensive Nontargeted Analysis of Fluorosurfactant Byproducts and Reaction Products in Wastewater from Semiconductor Manufacturing | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Comprehensive Nontargeted Analysis of Fluorosurfactant Byproducts and Reaction Products in Wastewater from Semiconductor Manufacturing YiJu Chen, Jheng-Sian Yang, Angela Yu-Chen Lin This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-3928681/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 15 Jul, 2024 Read the published version in Sustainable Environment Research → Version 1 posted 5 You are reading this latest preprint version Abstract Semiconductor manufacturing employs per- and polyfluoroalkyl substances (PFAS) as fluoroasurfactants to enhance the quality of photolithography lines. Our research, employing a fragment-based approach to investigate nontarget PFAS, overcomes conventional homologous series limitations. We identified 80 PFAS in wastewater and effluent samples from semiconductor industry, including 29 newly discovered compounds, categorized into three groups. First, primary PFAS formulations, such as perfluorobutane sulfonamide and perfluorobutane sulfonamido (di)ethanols, are accompanied by byproducts comprising approximately 0.1% of the total height compared to the main components. These byproducts, which exhibit variations in fluoroalkyl chains such as hydro-substituted, unsaturated, or ether structures, were reported for the first time to exist in commercially authentic standards, indicating their possible origin as byproducts of chemical manufacturing process. Second, transformation products from perfluorobutane sulfonamido ethanol during oxidation, including the first identified intermediate transformation compounds, perfluorobutane sulfonamido acetaldehyde and its hydrate, were obtained. Third, diverse reaction products are generated from the intricate processes of semiconductor manufacturing, which utilize strong acids, bases, and solvents under UV light or heated conditions. These processes include the formation of PFAS-related compounds through hydration, sulfonation, oxidation, and nitrification. This study revealed 22 isomeric PFAS, encompassing headgroup isomers and functional tail group isomers. These findings underscore the importance of comprehending diverse reactions and the overall emission compositions of PFAS in semiconductor wastewater, highlighting its complexity and presenting challenges for subsequent wastewater treatment. Per- and polyfluoroalkyl substances PFAS Semiconductor Perfluorobutane sulfonamido ethanol Perfluorobutane sulfonamide Transformation products Byproducts Aldehyde hydration Figures Figure 1 Figure 2 Figure 3 Figure 4 Introduction Perfluoroalkyl and polyfluoroalkyl substances (PFAS) have been extensively utilized in various industrial processes and commercial products, including food packaging, stain repellents, building materials, electronic devices, and firefighting foams. [ 1 – 3 ] The OECD's 2021 revision of the PFAS definition expands the range of fluorochemicals, classifying PFAS as fluorinated substances with at least one fully fluorinated methyl or methylene carbon atom (without any H/Cl/Br/I atom attached).[ 4 , 5 ] PFAS, with fluorine-substituted aliphatic carbon backbones, exhibit stability, low refractive index, and hydrophobic/oleophobic properties,[ 6 ] making them valuable for industrial surfactants.[ 7 ] PFAS have aroused concern owing to their health [ 8 ] and environmental impact. [ 9 ] Under TSCA Section 8(a)(7), the USEPA mandates reporting regulations for PFAS in 2023, requiring manufacturers and processors to submit detailed information on PFAS substance usage from 2011 to 2022, covering identification, applications, quantities, environmental impacts, and health effects.[ 10 ] PFHxS including its salts and PFHxS-related compounds, have been listed in the Stockholm Convention to restrict and eliminate their use since 2022. Over one hundred PFHxS-related compounds, defined as structures containing C 6 F 13 capable of degrading into PFHxS, have been listed in the convention. A significant portion of these structures belongs to sulfonamides and sulfonamido substances, such as C 6 F 13 S(O 2 )N-R (sulfonamides) and C 6 F 13 S(O 2 )O-R (sulfonate) and C 6 F 13 S(O 2 )-R (sulfones), which release PFHxS after undergo degradation in the environment. [ 11 ] [ 12 ]. Despite the convention's recommendation to use total oxidable precursors (TOPs)[ 13 , 14 ] and extractable organic fluorine (EOF)[ 15 ] for precursor identification, standardized methods for individual compounds are currently unavailable. [ 16 ] To identify nontarget PFAS, high-resolution tandem mass spectrometry has been used widely in contaminated soil,[ 17 , 18 ] surface water, [ 19 , 20 ], wastewater from a fluorochemical manufacturing, [ 21 ], and municipal wastewater,[ 22 ]. Mass defect and homologous patterns are potent tools for uncovering PFAS within a series of homologous substances. However, the chemicals employed in industrial processes exhibit diverse and precise functionalizations, making homologues less likely to occur in industrial manufacturing. Moreover, the intricate blend of industrial chemicals in sewage may undergo diverse reactions, such as hydration, oxidation and deamination. [ 23 ], , [ 24 , 25 ] As these reactions occur in the polar functional section, each transformation leads to distinct mass defect values, making the use of homologous patterns for screening impractical. Consequently, our research employed a fragment-based approach to investigate PFAS-related substances by screening the polar functional groups and nonpolar fluoroalkyl chains of fluorosurfactants. Ten sewage samples from five semiconductor plants and three effluents from their associated wastewater treatment plants (WWTPs) were investigated for comprehensive identifications of PFAS-related byproducts of chemical formulations, transformation products generated during the oxidation process, and diverse reaction products generated from the intricate processes of semiconductor manufacturing. Materials and methods Table S1 lists authentic reference standards used to establish the patterns for scanning fragmentation and neutral loss values in PFAS screening.. The Table S2 includes lists of authentic reference standards employed to confirm the identified PFAS. In November 2020 and January 2021, ten sewage samples (no. 184–187, 190, 191, 194–197) were collected from five semiconductor plants situated in three different Science Parks, along with three effluent samples (WWTP3, WWTP4, WWTP5) from their respective wastewater treatment plants, as depicted in Figure S1 . The samples were kept in 1 L polypropylene bottles and sent to the laboratory at 4°C for analysis. For nontarget analysis, a solid phase extraction cartridge (Oasis WAX, Waters) features a weak anion-exchange and reversed-phased sorbent was applied to condense water samples. The capture strategy involves performing the load and wash procedures at pH 8 for acidic PFAS. Detailed pretreatment procedures are included in the SI. The injection of a 50–100 µL extract was carried out using a UPHLC binary pump system and interfaced with a negative electrospray ionization source coupled to a Q-Exactive hybrid mass spectrometer. The mass spectrometric analysis was conducted in full MS and 20 data-dependent MS2 scans, involving a full scan analysis ranging from m/z 77-1155 with applied fragmentation energy (NCE 15 and 50). Mass calibration before each analysis ensured accurate results, and the inclusion of acetic acid in the calibration solution is crucial to enhance mass accuracy, especially for low mass measurements. Specific details regarding the LC gradient program and mass spectrometry settings can be found in Table S3. Thermo Scientific Compound Discoverer 3.3 software was employed for compound detection and identification, with identification confidence levels (CLs) adapted from Charbonnet's classification.[ 26 ] In particular, the Compound Class Scoring node (MS2) and the Search Neutral Losses node (MS2) were utilized for searching fragments and neutral losses, respectively, while the Search for ChemSpider node screened databases based on formulas within a 5 ppm mass tolerance (MS1). The detailed specifications of the workflow nodes are outlined in Table S4. Results and discussion 3.1 Nontarget analysis of PFAS and identified classes Screening functional polar heads is crucial for identifying nontargeted PFAS without apparent fluorocarbon fragments and discovering various reaction products formed in the polar functional groups during the semiconductor manufacturing. Nontarget identification is time-consuming and requires a harsh learning curve. Hence, we have streamlined the approach by summarizing the identified surfactant PFAS search through fragment and neutral loss screening of polar functional groups for the 12 classes with distinct polar functional groups, as shown in Table 1 for sulfonamido substances and Table 2 for fluoroalkyl acids. This strategy uniquely emphasizes the neutral loss of segments such as SO 3 , CONH, CH 3 OH, and H 2 O for miscellaneous FASAs and FASEs, highlighting its novelty in identifying reaction products reported for the first time. In addition, our study leads the way in developing neutral loss screens for CO 2 , HFCO 2 , C n H 2n CO 2 , etc., serving as indicators to distinguish classes such as carboxylic acid, dicarboxylic acid, and sulfonamido carboxylic acid, each characterized by terminal carboxylate structures. A list of the 80 identified PFAS and their formula, retention time, precursor ion, and theoretical m/z are provided in Table 3 . The following is a discussion of the identified results for the 12 classes with distinct polar functional groups. Table 1 Proposed strategies of fragmentation and neutral loss of sulfonamides and sulfonamido substances identified in this study No. Class Hydrophilic group Subclass Fragment 1 (m/z) Fragment 2 (m/z) Neutral loss (m/z) 1 Sulfonamides -SO 2 N(X)H Per-and polyfluoroalkyl sulfonamides 1 (X = H) and miscellaneous FASAs (X = SO 3 H, CONH 2 , CH 2 NO 2 , etc.) SO 2 N – (77.9644) [X-H] -SO 2 N(R')H N-Alkyl FASAs SO 2 H – (64.9697) SO 2 F – (82.9603) 2 Sulfonamido ethanols -SO 2 N(X)CH 2 CH 2 OH Per- and polyfluoroalky sulfonamido ethanol (FASEs (X = H) and miscellaneous FASEs (X = SO 3 H, CONH 2 ) SO 2 H – (64.9697) SO 2 NC 2 H 4 O – (121.9912) SO 2 NCH 2 – (91.9806) [X-H] -SO 2 N(R')CH 2 CH 2 OH N-Alkyl FASEs CH 3 CO 2 – (59.0139) 3 Sulfonamido diethanols -SO 2 N(CH 2 CH 2 OH) 2 N,N-bis(2-hydroxyethyl) per- and polyfluoroalkane sulfonamide (FASEE diol) SO 3 – (79.9563) SO 2 N(C 2 H 4 O) 2 – (166.0179) SO 2 N(C 2 H 4 )CH 2 – (136.00739) 4 Sulfonamido carboxylic acids -SO 2 N(H)C n H 2n CO 2 H 2 Per- and polyfluoroalkane 3 carboxylic acid (FASCAs) SO 2 N – (77.9644) SO 2 F – (82.9603) C n H 2n CO 2 2,3 -SO 2 N(R')CH 2 COOH N-Alkyl FASAAs SO 2 F – (82.9603) CH 2 CO 2 (58.0055) 5 Sulfonamido diacetic acids -SO 2 N(CH 2 COOH) 2 Per- and polyfluoroalkyl sulfonamido diacetic acid (FASEE diacid) SO 2 F – (82.9603) CH 2 CO 2 (58.0055) 6 N-ethylhydroxyl sulfonamido acetic acids -SO 2 N(CH 2 CH 2 OH) CH 2 COOH N-(2-hydroxyethyl) perfluoroalkane sulfonamido acetic acid (FASEE mono-ol monoacid) SO 2 F – (82.9603) SO 2 H – (64.9697) SO 2 NC 2 H 4 O – (121.9912) SO 2 NCH 2 – (91.9806) CH 2 CO 2 (58.0055) 7 Sulfonamido acetaldehyde -SO 2 NHCH 2 COH Per- and polyfluoroalkyl sulfonamido acetaldehyde (FASAceAL) SO 2 H – (64.9697) SO 2 – (63.96245) 8 Sulfonamido acetaldehyde hydrate/hemiacetal -SO 2 NHCH 2 CH(OH)(OX) (X = H (hydrate); X = CH 3 (hemiacetal)) Per- and polyfluoroalkyl sulfonamido acetaldehyde (FASAceAL hyrate/hemiacetal) SO 2 H – (64.9697) SO 2 – (63.96245) H 2 O (18.0106) MeOH (32.0262) 1: This subclass does not include fluorotelomer sulfonamides. In the series of fluorotelomer sulfonamides, the characteristic fragment is H 2 NSO 2 – [ 17 , 27 ], introduced by the significant presence of hydrogens in the fluorotelomer. However, the fluorotelomer series was not detected in this study; additional information for exclusion purposes is provided. 2: The neutral loss of sulfonamido carboxylic acid is C n H 2n CO 2 , exemplified by sulfonamido acetic acid (58.0055) and sulfonamido propanoic acid (72.02113). 3: The distinct neutral loss of CH 2 CO 2 might be affected by the significant presence of hydrogens in the fluorotelomer, resulting in the neutral loss of HF instead [ 27 ] However, the fluorotelomer series was not detected in this study; additional information for exclusion purposes is provided. Table 2 Proposed strategies of fragmentation and neutral loss of per- and polyfluoroalkyl acids (PFAAs) identified in this study No. Class Hydrophilic group Subclass Fragment 1 (m/z) Fragment 2 (m/z) Neutral loss (m/z) 9 Carboxylic acids -COOH Perfluoroalkyl carboxylic acids (PFCAs); Unsaturated PFCAs (U-PFCAs); Unsaturated perfluoroalkyl ether carboxylic acids (U-E-PFCAs) CO 2 (43.9893) Hydro substituted PFCAs (H-PFCAs); Hydro substituted E-PFCAs (H n -E-PFCAs) CO 2 HF (63.9961) CO 2 (43.9893) Perfluoroalkyl ether carboxylic acids (E-PFCAs) Not detected 10 Dicarboxylic acid -(COOH) 2 Perfluoroalkyl dicarboxylic acids (PFdiCAs) CO 2 (43.9893) 11 Sulfonic acid -SO 3 H Perfluoroalkane sulfonic acids (PFSAs) SO 3 – (79.9563) SO 3 F − (98.9547) Hydro substituted PFSAs (H-PFSAs) SO 3 − (79.9563) HF (20.0062) Hydro substituted and ether PFSAs (H n -E-PFSAs) SO 3 H – (80.96519) SO 3 − (79.9563) HF (20.0062) 12 Sulfinic acid -SO 2 H Perfluoroalkyl sulfinic acid SO 2 F – (82.9603) Table 3 Identified PFAS categorized by polar head class, subclass, theoretical precursor ion, retention time (RT), confidence level (CL), and first report. Class Subclass Aberration RT (min) Theoretical ion (m/z) CL First report 1 Sulfonamides –SO 2 NH 2 1a Perfluoroalkane sulfonamides (FASAs) FBSA 21.97 297.95897 1a 1b Hydro-substituted perfluoroalkyl sulfonamides (H-FASAs) H-FBSA 10.69 279.96840 3a V 1c Perfluoroalkyl ether sulfonamides (E-FASAs) E-FBSA 25.91(1) 27.37(2) 313.95389 2b V V Miscellaneous sulfonamides –SO 2 N(X)H 1d X:SO 3 H FBSA-SO 3 H 3.58 377.91579 2b V 1e X:CONH 2 FBSA-Am 8.72 340.96479 2b V 1f X:CH 2 CONH 2 FBSA-MeAm 10.72 354.98044 3a V 1g X:CH 2 NO 2 FBSA-MeNO 2 7.28 356.95970 3a V 1h X:C 3 H 6 NO 2 FBSA-PrNO 2 8.81 384.99100* 3a V 1i X:CH 2 N 2 H FBSA-diazene 22.28 339.98077 3a V N-alkyl sulfonamides –SO 2 N(R’)H 1j N-methyl perfluoroalkane sulfonamides (MeFASAs) R = CH 3 MeFBSA 36.77 311.97462 1a 2 Sulfonamido ethanols –SO 2 N(H)CH 2 CH 2 OH 2a Perfluoroalkane sulfonamido ethanols (FASEs) FEtSE 9.46 241.99158 2b FPrSE 18.47 291.98838 2b FBSE 30.00 341.98519 1b 2b Hydro substituted perfluoroalkane sulfonamido ethanols (H-FASEs) H-FBSE 15.84 323.99461 3a V 2c Perfluoroalkyl ether sulfonamido ethanols (E-FASEs) E-FBSE 33.94 (1) 34.28 (2) 35.10 (3) 357.98010 2b 2b 2b V V V 2d Hydrogen substituted perfluoroalkyl ether sulfonamido ethanols (E-H-FASEs) H-E-FBSE 21.41 339.98952 3a V 2e Unsaturated perfluoroalkyl sulfonamido ethanols (U-FASEs) U-FBSE 16.76 303.98838 3a V 2f unsaturated perfluoroalkyl ether sulfonamido ethanols (U-E-FASEs) U-E-FBSE 23.78 319.98330 3a V Miscellaneous sulfonamido ethanols –SO 2 N(X)CH 2 CH 2 OH 2g X:SO 3 H FBSE-SO 3 H 17.79 421.94200 2b V 2h X:CONH 2 FBSE-Am 29.97 384.99100* 2b V N-alkyl sulfonamido ethanols –SO 2 N(R’) CH 2 CH 2 OH 2i N-methyl perfluoroalkane sulfonamido ethanols (MeFASEs) R = CH 3 MeFBSE 35.21 416.02197 1a V 293 Sulfonamido diethanols –SO 2 N(CH 2 CH 2 OH) 2 3a N,N-bis(2-hydroxyethyl) perfluoroalkane sulfonamides (FASEE diols) FBSEE 31.52 386.01140 446.03253 432.01688 773.03008 1a 3b Hydro-substituted FASEE diol (H-FASEE diols) H-FBSEE 16.96 428.04195 2b V 4 Sulfonamido carboxylic acids – SO 2 NH(CH 2 ) n COOH 4a perfluoroalkane sulfonamido acetic acids (FASAAs) FBSAA 9.93 (1) 15.50 (2) 355.96445 1b V 4b Hydro-substituted FASAAs (H-FASAAs) H-FBSAA 7.29 337.97387 3a V 4c Perfluoroalky ether sulfonamido acetic acids (E-FASAAs) E-FBSAA 18.73 (1) 19.73 (2) 371.95937 3a 3a V V 4d N-methyl FASAAs (N-MeFASAAs) N-MeFBSAA 20.38 369.98120* 1a 4e Perfluoroalkane sulfonamido propanoic acids (FASPrAs) N-FBSPrA 19.06 369.98120* 2b V 5 Sulfonamido diacetic acids –SO 2 N(CH 2 COOH) 2 5a perfluoroalkane sulfonamido diacetic acids (FASEE diacids) FBSEE diacid 5.83 413.96993 2b 6 N-ethylhydroxyl sulfonamido acetic acids –SO 2 N (CH 2 CH 2 OH) (CH 2 COOH) 6a N-(2-hydroxyethyl) perfluoroalkane sulfonamido acetic acids (FASEE mono-ol monoacid) FBSEE mono-ol monoacid 17.10 399.99067 2b 7 Sulfonamido acetaldehyde –SO 2 N(H)CH 2 COH 7 Perfluoroalkane sulfonamido acetaldehyde FBSAcAL 13.03 (1) 30.03 (2) 339.96954 3a 3a V V 8 Sulfonamido acealdehyde hydrate/hemiacetal –SO 2 N(H)CH 2 C (OH)(OR)H 8a Perfluoroalkane sulfonamido acetaldehyde hydrate (R = H) FBSAcAL hydrate 32.63 357.98010 2b V 8b Perfluoroalkane sulfonamido acetaldehyde hemiacetal (R = CH 3 ) FBSAcAL hemiacetal 33.16 371.99575 2b V 9 Carboxylic acid 9a Perfluoroalkyl carboxylic acids (PFCAs) TFA 1.38 112.98559 1a –COOH PFPrA 2.65 162.98239 1a PFBA 4.43 212.97920 1a PFPeA 8.15 262.97600 1a PFHxA 15.87 312.97281 1a PFHpA 25.52 362.96962 1a PFOA 35.28 412.96642 1a PFNA 45.98 462.96323 1a PFDA 54.82 512.96003 1a PFUdA 63.08 562.95684 1a 9b Unsaturated PFCAs (U-PFCAs) U-PFHxA 10.53 274.97600 3a 9c Unsaturated-E-PFCAs (U-E-PFCAs) U-E-PFBA 3.20 190.97731 3a U-E-PFPeA 3.29 (1) 6.36 (2) 240.97411 3a 3a U-E-PFHxA 3.66 (1) 5.80 (2) 11.07 (3) 290.97092 3a 3a 3a 9d Hydro-substituted PFCAs (H-PFCAs) H-PFBA 3.23 194.98862 3a H-PFPeA 4.74 244.98543 3a H-PFHxA 9.35 294.98223 3a 9e Hydro-substituted E-PFCAs (H-E-PFCAs) H-E-PFPrA 1.9 160.98673 3a H-E-PFBA 3.13 (1) 3.77 (2) 9.83 (3) 210.98353 3a 3a 3a Multihydro-substituted E-PFCAs (H n -E-PFCAs) H 2 -E-PFBA 1.77 192.99296 3a 9f Per- and polyfluoroalkyl ether carboxylic acids (E-PFCAs) E- PFPrA 3.36 178.97731 3a E- PFBA 5.82 228.97411 3a E- PFPeA 10.14 278.97092 3a 10 Dicarboxylic acid –(COOH) 2 10a Perfluoroalkyl dicarboxylic acids (PFdiCAs) PFdiCA(C3) 1.01 138.98484 3c PFdiCA(C4) 1.13 188.98164 2c PFdiCA(C5) 1.18 238.97845 2c PFdiCA(C6) 1.25 288.97525 2b PFdiCA(C7) 2.54 338.97206 3c PFdiCA(C8) 3.57 388.96887 2c 11 Sulfonic acid –SO 3 H 11a Perfluoroalkane sulfonic acids (PFSAs) TFMS 1.77 148.95257 1a PFBS 9.83 298.94299 1a 11b Hydro substituted PFSAs (H-PFSAs) H-PFEtS 1.91 180.95880 3a H-PFPrS 3.57 230.95560 3a H-PFBS 5.18 280.95241 3a 11c Hydro substituted perfluoroalkyl ether sulfonic acids (H n -E-PFSAs) H 2 -E-PFPrS 2.57 228.95994 3a 12 Sulfinic acids –SO 2 H 12 Perfluoroalkyl sulfinic acids (PFSiA) PFBSi 11.39 282.94807 1a *: the presence of structural isomers in other subclasses Class 1 Sulfonamides By searching for NSO 2 – fragment searching and excluding substances lacking fluorine based on isotopic formulas, we identified the predominant perfluoroalkane sulfonamides (FASAs) and various FASA series chemicals, resulting in the detection of 9 subclasses (1a-1i). Among them, 3 subclasses (1a-1c) displayed variations in the fluoroalkyl chain but had a polar head of -SO 2 NH 2 . This class, which features sulfonyl groups linked to amines (–SO 2 NH 2 ), exhibits a unique characteristic fragment, SO 2 N- (77.9644), which is observed in perfluorobutane sulfonamide (FBSA), hydro-substituted FBSA (H-FBSA), and ether FBSA (E-FBSA). Notably, no obvious fragmentations from the fluoroalkyl tail were detected during screening, suggesting that SO 2 N- is a feasible screening tool for identifying these subclasses. In Figure S3, the CL for H-FBSA reamined at 3a, reflecting uncertainty about the position of the hydrogen. E-FBSA, which has two isomers, was recognized by its specific ether fragments CF 3 O − (84.99067) and C 2 F 5 O − (134.98748) with an isotope pattern matching of C 4 F 9 H 2 O 3 SN (Fig. 4 a and 4 b) and the CL was set to 2b. The remaining 6 subclasses (1d-1i) featured a fixed fluoroalkyl chain as perfluorobutane but showed variations in the functional group as -SO 2 N(X)H. The miscellaneous FASAs with the structure C 4 F 9 SO 2 NHX (X = SO 3 H; CONH 2 ; CH 2 CONH 2 ; CH 2 NO 2 ; C 3 H 6 NO 2 ; CH 2 N 2 H, subclass 1d-1i) were identified with the fragment of SO 2 N − (77.9644). Additional indicators of these subclasses were observed through the neutral loss of X-H, such as the subclass with a neutral loss of C 3 H 5 NO 2 (Figure S5), representing a novel screening approach for miscellaneous FASAs and being reported for the first time. Notably, in the presence of substances with N-alkyl substitutions, SO 2 − (63.9625) and SO 2 H − (64.9697) became dominant fragments and the weak fragment SO 2 F − (82.9603) was observed. N-Methyl perfluorobutane sulfonamide (MeFBSA) was identified in the effluents of WWTP3 and WWTP4 (Figure S6a). The confirmation of the authentic standard of MeFBSA resulted in setting the CL to 1 (Figure S6b). To the best of our knowledge, 9 identified PFAS (including 2 E-FBSA isomers) of these subclasses have been reported for the first time, as shown in Table 3 . Remarkably, fluorotelomer sulfonamides identified by other researchers are detected with the H 2 NSO 2 - fragment [ 17 , 27 ], distinguishing them from perfluoroalkane sulfonamides (FASAs), H-FASA, H-E-FASA, and U-FASA in our study, which exhibit the characteristic NSO 2 – fragment. The introduction of the H2NSO 2 – fragment is attributed to the substantial presence of hydrogens in the fluorotelomer. Class 2 Sulfonamido ethanols The class has a structure where sulfonamido is linked to a hydroxyethyl group, and its main characteristic fragments are SO 2 NC 2 H 4 O – (121.9912) and SO 2 NCH 2 – (91.9806). By conducting SO 2 NC 2 H 4 O – and SO 2 NCH 2 – fragment searching and subseqently excluding substances lacking fluorine based on isotopic formulas, we identified the predominant perfluoroalkane sulfonamido ehtaol (FASEs) and miscellaneous FASE series, resulting in the detection of 8 subclasses (2a-2h). Among them, 6 subclasses (2a-2f) displaying variations in the fluoroalkyl chain were effectively identified, including perfluorobutane sulfonamido ethanol (FBSE), hydro-substituted perfluorobutane sulfonamido ethanol (H-FBSE), perfluorobutyl ether sulfonamido ehtanol (E-FBSE), hydro-substituted perfluorobutyl ether sulfonamido ehtanol (H-E-FBSE), unsaturated perfluorobutane sulfonamido ehtanol (U-FBSE), and unsaturated perfluorobutyl ether sulfonamido ehtanol (U-FBSE). Figure S7 displays the MS2 spectrum and proposed structure of hydro-substituted perfluorobutane sulfonamido ethanol (H-FBSE). The confidence level for H-FBSE remains at 3a due to uncertainties in identifying the position of hydrogen. Next, three isomers of perfluorobutyl ether sulfonamide ethanol (E-FBSE) were identified and three characteristic peaks from fragments CF 3 O − , C 3 F 7 O − , and C 2 F 5 O − were observed by chromatography, and their structures were proposed (Figure S8a, 8b, 8c) with a confidence level of 2b. The greater retention time (RT 35.13 min) of the E-FBSE isomer was indicative of the increased symmetry of the alkyl structure matching the proposed structure. The presence of hydrogen-substituted perfluorobutyl ether sulfonamido ethanols (H-E-FBSEs) with the specific fluoroalkyl ether fragment C 2 F 3 O − (96.99074, 0.72 ppm) was indicative of the loss of HF from C 2 F 4 HO − (116.99708, 1.54 ppm). U-FBSE with the fragment C 4 F 7 − (180.98955, 0.99 ppm) was detected. We proposed a confidence level of 3a due to the lack of further information to determine the position of the double bond. Unsaturated perfluoroalkyl ether sulfonamido ethanols (U-E-FASEs) with the specific fragments C 3 F 5 -(130.99281, 1.91 ppm) and C 4 F 7 O-(196.98503, 3.79 ppm) were detected, which suggested the position of the oxygen atom (Figure S9). However, the position of the unsaturated bond remained uncertain, so the confidence level was set to 3a. To the best of our knowledge, 5 subclasses (subclasses 2b-2f) of FASEs with various fluoroalkyl chains have been reported for the first time (Table 3 ). In addition, miscellaneous FBSEs with the structure C 4 F 9 SO 2 N(X)(C 2 H 4 OH) (X:SO 3 H; X:CONH 2 ) were detected in subclasses 2g and 2h, identified through characteristic fragment SO 2 NC 2 H 4 O – (121.9912) screening. Notably, subclasses 2g and 2h could be detected through neutral loss screening of SO 3 and CONH. (Figure S10) To explore the subclass (2i) of N-alkyl perfluoroalkane sulfonamido ethanol, we examined MeFOSE and EtFOSE with authentic standards, revealing characteristic MS2 spectra of this subclass. Both MeFOSE and EtFOSE displayed an acetate adduct [M + CH 3 COO] − . In alkyl-substituted sulfonamido ethanol, no SO 2 NC 2 H 4 O − (121.9912) and SO 2 NCH 2 − (91.9806) fragments were observed; only CH 3 COO − (59.01385) appeared. Screening of the acetate adduct of MeFBSE (416.02197) in sample no. 190 revealed fragments of SO 2 NC 2 H 4 O − (121.99250) and SO 2 H − (64.97031) at RT 35.82 (Fig. 11a). The MeFBSE in Sample no. 190, presumed to be branched, contained fragments of SO 2 NC 2 H 4 O − (121.99250) and SO 2 H − (64.97031), possibly distinct from the linear form of authentic standard (Fig. 11b). Owing to the lack of additional fragments, we assigned CL for MeFBSE as 1b due to insufficient isomeric data. Remarkably, fluorotelomer sulfonamido ethanol, such as 6:2 FTSAm-EtOH, which was identified by other researchers are detected, contains the SO 2 NC 2 H 4 O − (121.9912) fragment.[ 27 ] This fragment, elucidated as SO 2 NC 2 H 4 O − (121.9912), remains unaffected by the functional fluoroalkyl chain, including fluorotelemer, serving as a unique indicator of the class of sulfonamido ethanol. Class 3 Sulfonamido diethanol N,N-bis(2-hydroxyethyl)perfluorobutane sulfonamide (FBSEE diol) was identified and detected in the form of an acetate adduct [M + CH 3 COO] − , [M-H] − , a formate adduct [M + HCOO] − , and a dimer ion [2M-H] − , in the order of their observed intensities (Figure S12). This structure exhibited characteristic fragments, including SO 2 N(C 2 H 4 O) 2 − , SO 2 N(C 2 H 4 O)CH 2 − , and SO 2 NC 2 H 4 O − . Additionally, the high-intensity SO 3 − fragment serves as a confirming marker. FBSEE diol exhibited a weak characteristic fragment of the fluorobutyl fragment C 4 F 9 − , highlighting the feasibility of the screening method based on its functional group, as shown in Figure S13a and 13b. Hydrogen-substituted FBSEE diol (H-FBSEE diol) was detected with an acetate adduct and the unique fragment O 2 SN(C 2 H 4 O) 2 − (166.0174, -2.16 ppm) for the first time. The confidence level was set to 3a due to insufficient data to determine the position of hydrogen Class 4 Sulfonamido carboxylic acid This subclass features a structure with sulfonamido linked to a carboxylic acid group, releasing the carboxylic acid group during collision and producing characteristic fragments such as SO 2 N − (77.9644) and SO 2 F − (82.9603). A precursor ion at 355.96460, with a neutral loss of CH 2 CO 2 (-1.86 ppm), was identified as perfluorobutane sulfonamido acetic acid (FBSAA) (Figure S14a) and confirmed by its authentic standard at CL1 (Figure S14b). This series of compounds consistently exhibited a neutral loss of CH 2 CO 2 (58.00548 Da), demonstrating further identification of H-FBSAA (Figure S15), E-FBSAA, and N-methyl FBSAA (MeFBSAA) (Figure S16a). Perfluorobutyl ether sulfonamido acetic acid (E-FBSAA), which has two structural isomers, was separated with the column at retention times of 18.73 min and 19.73 min). Fragments of fluoroether CF 3 O − and C 2 F 5 O − were observed and providing the position of oxygen for the CL at 2b. MeFBSAA with isotope matching to C 7 H 6 F 9 NO 4 S (369.9790, -2.98 ppm) (Figure S16a) was confirmed by the matching RT and MS2 spectra of the authentic standards (Figure S16b). Notably, a structural isomer of MeFBSAA, C 7 H 6 F 9 NO 4 S (369.97022, -2.38 ppm), was identified for the first time as perfluorobutane sulfonamido propanoic acid (FBSPrA) (Figure S16). The neutral loss of C 2 H 4 CO 2 released from collision indicates propanoic acid. The presence of only SO 2 F − (82.9603) fragments, not SO 2 N − (77.9644), serves as a distinguishing rule between FASAA and N-alkyl FASAA. Notably, the distinct neutral loss of CH 2 CO 2 might be affected by the significant presence of hydrogens in the fluorotelomer, resulting in the neutral loss of HF instead [ 27 ]. However, the fluorotelomer series was not detected in this study; additional information for exclusion purposes is provided. Class 5 sulfonamido diacetic acid The MS2 spectrum of sulfonamido diacetic acid shows two pairs of neutral losses of CH 2 O 2 , indicating the presence of the diacetic acid structure. The main characteristic fragment was SO 2 F − (82.9603), while the intensity of SO 2 N − (77.9644) was notably weak. Perfluorobutane sulfonamido diacetic acid was identified with CL to 2b.[ 28 ] Class 6 N-hydroxyethyl sulfonamido acetic acid The substance with the precursor ion 399.9903 was identified by the specific fragment of O 2 SNC 2 H 4 O − (121.9912). The An obvious fragment 341.9852 was referred to as the FBSE fragment. The difference between 341.9852 and 399.9903 represents the neutral loss of CH 2 CO 2 . Consequently, we referred to this substance as N-(2-hydroxyethyl) perfluorobutane sulfonamido acetic acid (FBSEE mono-ol monoacid) at confidence level 2b.[ 28 ] Class 7 Sulfonamido acealdehyde The class with the structure where sulfonamido linked to acetaldehyde. C 6 H 3 F 9 NO 3 S – (339.97025, 2.09 ppm) was observed with the fragments O 2 S – (63.96249, 0.67 ppm) and HO 2 S – (64.97031, 0.58 ppm), along with the retention time of 30.06 min, which was detected for the first time as perfluorobutane sulfonamido acetaldehyde (Figure S18). Class 8 Sulfonamido acealdehyde hydrate/hemiacetal C 6 H 5 F 9 NO 4 S – (357.98, ppm) was observed with a neutral loss of H 2 O which was identified as perfluoroalkane sulfonamido acetaldehyde hydrate, as water adds to the carbonyl function of acetaldehydes (Figure S19). Moreover, C 7 H 7 F 9 NO 4 S – (371.99, ppm) was detected with a neutral loss of CH 3 OH, which indicated the production of additional reaction of methanol to acetaldehyde. Hydrates and hemiacetals are the products of addition reactions of oxygen-based nucleophiles, such as water and methanol, to aldehydes, which have been reported for the first time. Class 9 carboxylic acid The classes comprising 6 subclasses, 9a-9f, all contained the -COOH functional group. Among these subclasses, three subclasses including perfluoroalkyl carboxylic acids (PFCAs), unsaturated PFCAs (U-PFCAs), and unsaturated perfluoroalkyl ether carboxylic acid (U-E-PFCAs) could be distinguished by the neutral loss of CO 2 . The MS2 spectrum of U-E-PFCA(C6) is shown in Figure S20. In addition, hydro-substituted PFCAs (H-PFCAs), hydro-substituted E-PFCAs (H-E-PFCAs) and H n -E-PFCAs (subclasses 9a, 9b, 9c, 9d, and 9e) produced neutral loss of CO 2 HF, which was derived through the combination of CO 2 and HF, with HF originating from the hydrogen-substituted fluoroalkyl chain, as shown in Figure S21 and Figure S22 for H-PFCA(C4) and H 2 -E-PFCA(C4) respectively. Perfluoroalkyl ether carboxylic acid (E-PFCA) did not cuase the neutral loss of CO 2 . This lack of detection of [M-H] – and [M-H-CO 2 ] – was probably due to in-source fragmentation of the precursor ion.[ 19 , 29 , 30 ] Therefore, the C n F 2n+1 O – fragments and the isotope pattern with fluoride were used for identification of this subclass. Class 10 dicarboxylic acid Perfluoroalkyl dioic acids (PFdiCA, C3-C8) are comprised of the functional group of dicarboxylic acid. PFdiCA (C3-C5) exhibited a neutral loss of CO 2 ; PFdiCA (C6-C8) lacked the detection of neutral loss of CO 2 , presumably due to their low abundance in the samples. The fragment-based fluoroalkyl chain as C n F 2n−1 and the isotopic pattern of fluorine could be alternatives to identify this subclass. Fragments of C 2 F 3 – , C 3 F 5 – , C 4 F 7 – , C 5 F 9 – , and C 6 F 11 – (C n F 2n−1 – ) were detected in the spectrum of PFdiCA(C4 to C8) respectively. The fragment C 2 HF 2 O 2 – , C 3 HF 4 O 2 – , C 4 HF 6 O 2 – were detected by the neutral loss of CO 2 from [M-H] − of PFdiCA(C3-C5). Class 11 sulfonic acid Perfluoroalkyl sulfonic acids (PFSAs, subclass 11a, C1 and C4) and hydrogen-substituted PFSA (H-PFSA, subclass 11b, C2-C4) were distinguished by the presence of SO 3 − and SO 3 F − . In the case of multi-hydrogen-substituted perfluoroalkyl ether sulfonic acids (H 2 -E-PFSA, C4), the dominant fragments of polar head shifted from SO 3 − to HSO 3 − . Additionally, for the subclasses with hydrogen-substituted PFSAs, such as H-PFSA(C2, C3) and H 2 -E-PFSA (C4), a neutral loss of HF was observed (Figure S23). Class 12 Sulfinic acid Subclass 4 perfluorobutyl sulfinate (PFBSi) was identified with clear fragments of SO 2 F − as the specific feature of sulfinic acid. It was further confirmed with an authentic standard based on the retention time and the MS/MS spectrum. Perfluoroalkane sulfinic acids, arising from the degradation of commercial precursor compounds containing the C n F 2n+1 SO 2 N moiety, may act as degradation by-products of fluorosurfactants in 3M foam.[ 3 , 28 ] 3.2 Byproducts from chemical formulation Two primary methods for PFAS production are the electrochemical fluorination (ECF) process, favored by 3M,[ 31 , 32 ] and the telomerization process, employed by DuPont.[ 33 ] The ECF process generates byproducts, along with both shorter and longer PFAS, with a higher prevalence of branched PFAS, while the telomerization process primarily yields normal PFAS.[ 34 ] In our previous study on semiconductor wastewater,[ 28 ] FBSE was found at concentrations ranging from 0.883 to 482 µg/L. FBSE is associated with 3M's electronic surfactant 4200,[ 35 ] which is added to buffered hydrofluoric acid (BHF) for etching solutions in semiconductor manufacturing to enhance wetting properties and improving pattern quantity performance. In this study, we reported several FBSE derivatives with varying fluoroalkyl chain lengths in wastewater. The relative proportions to FBSE are as follows, in descending order: H-FBSE (0.06%), E-FBSE (0.03%), U-E-FBSE (0.005%), U-FBSE (0.004%), H-E-FBSE (0.001%), FPrSE (0.004%) and FEtSE (0.001%) contribute to a total of approximately 0.1%. The varied retention times (RTs) of these substances compared to that of FBSE (29.9 min) are as follows: E-FBSE (33.8–34.9 min) > U-E-FBSE (23.3 min) ≈ H-E-FBSE (21.1min) > U-FBSE (16.9 min) ≈ H-FBSE (16.0 min) and FPrSE (18.4 min) and FEtSE (9.4 min). The use of a reversed-phase C18 column for analysis indicates that, in terms of polarity, only E-FBSE was less polar than FBSE, while the others were less polar, resulting in faster elution. This suggests that in wastewater treatment, using hydrophobic interaction separation methods such as activated carbon adsorption may lead to lower removal efficiency for these polar substances, decreasing susceptibility to adsorption removal. When discharged from wastewater treatment plants, the environmental distribution of these substances may differ significantly due to their distinct properties, which should also be considered. The aforementioned FBSE derivative series, including H-FBSE, U-E-FBSE, U-FBSE, E-FBSE, H-E-FBSE, FPrSE, and FEtSE, was confirmed to exist in accordance with the authentic standard of FBSE. However, due to uncertainties about any additional separation in the standard production process, we refrained from directly comparing the proportions of the FBSE derivative series in the standard to those in the samples. In addition, FBSA includes similar byproducts from production, such as H-FBSA and E-FBSA. Nevertheless, we infer that the aforementioned FBSE derivative series and FBSA derivatives may be byproducts produced during the formulation of chemicals used by semiconductor factories. 3.3 Reaction products Due to the intricate nature of semiconductor processes, among the 12 prominent semiconductor industries in South Korea, 11 utilize 135 chemical constituents.[ 36 ] These include sulfuric acid, chromic acid, tetramethyl ammonium hydroxide, ethylene oxide, potassium dichromate, isopropanol, and formaldehyde. Despite this extensive usage, 33% (range: 16–56%) of the chemical compositions remain undisclosed due to commercial confidentiality. Notably, the undisclosed ingredients are predominantly employed in the photolithography process. The complex chemical condition involved in these semiconductor processes include strong acids, alkalis, and potent oxidants, and UV light is used in the photolithography process. Among the intricate blends of industrial chemicals in sewage, various reactions may take place, including hydration, oxidation, sulfonation, amide formation, and nitration. Additionally, during the biological treatment in wastewater treatment plants, reactions such as oxidation, deamination, desulfonation, and dicarboxylation occur. Due to the exceptional stability of the fluoroalkyl chain, reactions in the polar functional section led to distinct mass defect values for each transformation. This renders the use of homologous patterns for screening impractical. Our fragment-based approach overcomes the limitations of conventional homologous series. In total, we have identified 80 PFAS from 43 subclasses, with 29 substances reported for the first time. (Table 3 ) Oxidizing FBSEE diol yields FBSEE diacid, and FBSE oxidation produces tentatively identified FBSAA. Due to the lack of standards, the tentative identifications of FBSEE diacid and FBSAA remained at CL 2b. [ 28 ] A key distinction in current study is the inclusion of a standard for FBSAA confirmation. Through RT alignment and consistent MS2 spectra, we verified the presence of PFBSAA at 15.5 minutes with CL1. Notably, an isomer of FBSAA with higher polarity presented at RT 9.93 minutes, showcasing distinct MS2 spectra (Fig. 1 4c) that suggest structural differences. Considering the potential isomerization between acid and diol forms [ 37 ], fragment analysis led to the proposal of a diol structure for the isomers. However, based on the fragments observed in the MS2 spectrum, the potential existence of another structural isomer is suggested, which is simultaneously illustrated in Figure S16c. In addition, we introduce intermediate products of FBSE oxidation: FBSAcAL (RT 29.94 min) and its hydrated form as FBSAcAL hydrate, detected for the first time via mass spectrometry. Another structural isomer of FBSAcAL at RT 13.03 minutes was identified with higher polarity. Here, we propose an oxidation pathway, including the first publication of intermediate transformations of aldehyde, aldehyde hydrate, and FBSAA in Fig. 1 . FBSA-PrNO 2 and FBSE-Am are isomers with distinct polar head groups—sulfonamide and sulfonamido ethanol, respectively. (Fig. 2 ) FBSA-PrNO 2 exhibit SO 2 N − fragment along with an additional signal for the neutral loss of C 3 H 5 NO 2 , categorizing it as miscellaneous FASAs (Subclass 1h). In contrast, FBSE-Am demonstrates a specific signal at 121.99174, confirming its classification as FASEs, and its neutral loss of CONH categorizes it within the miscellaneous FASEs (Subclass 2h). The retention time of FBSA-PrNO 2 was 8.81 minutes, while that of FBSE-Am was 29.97 minutes, indicating significant differences in polarity. Thus, the headgroup isomers exhibit unique reactivity and physicochemical properties, may impact the variations in sludge metabolism during wastewater treatment in WWTPs[ 38 ]. Furthermore, E-FBSEs and FBSEAcAL hydrate (Subclass 8a) are differentiated by their respective polar head groups: sulfonamido ethanol and sulfonamido acetaldehyde hydrate. (Fig. 3 ) Specifically, fragment 121.99174 is unique to sulfonamido ethanol, while the hydrate can be identified by the neutral loss of H 2 O. Finally, MeFBSAA and FBSPrA, which are polar head isomers, exhibit differences in the number of carbons in the sulfonamido carboxylic acid. (Fig. 4 ) This clearly results in distinct neutral losses—one for acetic acid (CH 2 CO 2 ) and the other for propanoic acid (C 2 H 4 CO 2 ). Additionally, MeFASAA showed no NSO 2 − fragment signal, indicating solely the presence of only the SO 2 F − fragment signal due to N-methyl substitution. Conversely, FBSPrA exhibited a distinct NSO 2 − fragment, signifying the lack of N-alkylation. The specific fragmentation patterns have been classified under class 4 in Table 1 . This investigation unveiled 22 isomeric PFAS, including isomers with different headgroups and functional tail groups. These results emphasize the significance of understanding varied reactions and the overall composition of PFAS emissions in semiconductor wastewater, highlighting its complexity and posing challenges for subsequent wastewater treatment. Conclusion For the nontarget PFAS approach, mass defect and homologous patterns are potent tools for uncovering PFAS within a series of homologous substances. However, industrial chemicals exhibit diverse and unique functional groups, making homologues less likely to occur in industrial manufacturing. Moreover, the intricate blend of industrial chemicals in sewage may undergo diverse reactions, such as hydrolysis, oxidation and deamination. As these reactions unfold in the polar functional section, each transformation leads to distinct mass defect values, rendering the use of homologous patterns for screening. Consequently, our research employs a fragment-based approach to investigate nontarget PFAS, particularly focusing on hydrophilic head groups, overcoming the limitations of conventional homologous series. Utilizing this approach, we successfully identified 80 PFAS in sewage and effluent samples from semiconductor plants, including 29 newly discovered compounds, which are categorized into three groups (1) The byproducts of primary PFAS formulations, such as perfluorobutane sulfonamide and perfluorobutane sulfonamido (di)ethanols, include components that constitute less than 0.1% of the total area compared to the main components. These byproducts, which exhibit variations in fluoroalkyl chains such as hydrogen-substituted, unsaturated, and ether structures, were identified for the first time in authentic standards, suggesting that they originated as byproducts from the chemical manufacturing process. (2) Compounds that undergo intermediate transformation compounds during the oxidation of perfluorobutane sulfonamido ethanol, specifically perfluorobutane sulfonamido acetaldehyde and its hydrate, are newly identified. (3) Diverse reaction products generated from the intricate processes of semiconductor manufacturing, which utilize strong acids, bases, and solvents under UV light or heat conditions, include novel PFAS-related reaction compounds generated through hydrolysis, sulfonation and nitrification. In brief, these discoveries underscore the efficacy of the fragment-based approach in identifying unique industrial chemicals and its value in understanding diverse reactions and the actual emission compositions of PFAS in semiconductor wastewater. Moreover, under the Stockholm Convention's regulation for PFAS precursor elimination, complexity arises due to the absence of standards and standardized identification methods for diverse PFAS precursors, which undergo degradation to form terminal PFAS through the amendment of polar functional groups. This poses challenges in recognizing and quantifying the levels of products, complicating market surveillance. Our streamlined fragment-based approach addresses these hurdles and provides a strategic concept for identifying PFAS precursors, particularly those exhibiting versatility in polar functional groups. Declarations Acknowledgments We extend our gratitude to Tzu-Hui Wang for her support in the pretreatment procedures and Meng-Chi Huang for his assistance in verifying the chemical structures. Authors’ contributions Yi-Ju Chen: study design, experimental work, data analysis, writing and editing manuscript. Jheng-Sian Yang: experimental work and editing manuscript. Angela Yu-Chen Lin: supervision and funding acquisition. The authors read and approved the final manuscript. Funding Financial support for this study was provided by the Taiwan National Science and Technology Council through the following projects: MOST 111–2221-E-002–047-MY3 and MOST 111–2221-E-002–042-MY3. Availability of data and materials All data generated or analyzed during this study are included within the article. Competing interests The authors declare that they have no competing interest. Author details 1 National Environmental Research Academy, Ministry of Environment, Taoyuan City, 320, Taiwan. 2 Graduate Institute of Environmental Engineering, National Taiwan University, Taipei City, 106, Taiwan References Glüge J, Scheringer M, Cousins IT, DeWitt JC, Goldenman G, Herzke D, et al. An overview of the uses of per- and polyfluoroalkyl substances (PFAS). Environ Sci Process Impacts 2020;22(12):2345–73. Han J, Kiss L, Mei H, Remete AM, Ponikvar-Svet M, Sedgwick DM, et al. 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Londhe K, Lee C-S, McDonough CA, Venkatesan AK. The Need for Testing Isomer Profiles of Perfluoroalkyl Substances to Evaluate Treatment Processes. Environmental Science & Technology 2022;56(22):15207–19. Supplementary Files SI0131SER.docx Cite Share Download PDF Status: Published Journal Publication published 15 Jul, 2024 Read the published version in Sustainable Environment Research → Version 1 posted Editorial decision: Major revision 14 Mar, 2024 Reviewers agreed at journal 22 Feb, 2024 Reviewers invited by journal 22 Feb, 2024 Editor assigned by journal 07 Feb, 2024 First submitted to journal 05 Feb, 2024 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-3928681","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":274595469,"identity":"dd0dd9d5-5612-479c-b329-cf866e037ca2","order_by":0,"name":"YiJu Chen","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAz0lEQVRIiWNgGAWjYFCCA2xAwoZ0LWlIAmyE9YCUHCZBi8HBw88efNxxPpqfvfeYBMMvm8QG+R4D/FoOHDM3nHnmdu7MnnNpEox9aYkNbDyEtJxhk+Ztu5274UaOsQFjz2FjBjbeDYS1/G07l7vh/htStDC2HQDawmP4gOHHYTmCWiQPHDOT7G1LBvolx/BBYkOaHBtb/ge8WvhuHH4m8bPNLref/YzBgQ9/bHj4mY8l4NWicOMAEi+xjYiYlO9vQOb+IaR+FIyCUTAKRiIAAI8CSp9CEzlJAAAAAElFTkSuQmCC","orcid":"https://orcid.org/0009-0009-7923-6908","institution":"Environmental Governance Research Center","correspondingAuthor":true,"prefix":"","firstName":"YiJu","middleName":"","lastName":"Chen","suffix":""},{"id":274595470,"identity":"3c3d2073-d29f-49bd-b42d-9cf3c806432a","order_by":1,"name":"Jheng-Sian Yang","email":"","orcid":"","institution":"National Taiwan University Graduate Institute of Environmental Engineering","correspondingAuthor":false,"prefix":"","firstName":"Jheng-Sian","middleName":"","lastName":"Yang","suffix":""},{"id":274595471,"identity":"effe7498-a4bf-49a8-8c76-0fe8f35584f7","order_by":2,"name":"Angela Yu-Chen Lin","email":"","orcid":"https://orcid.org/0000-0003-4236-7233","institution":"National Taiwan University Graduate Institute of Environmental Engineering","correspondingAuthor":false,"prefix":"","firstName":"Angela","middleName":"Yu-Chen","lastName":"Lin","suffix":""}],"badges":[],"createdAt":"2024-02-04 19:57:13","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-3928681/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-3928681/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1186/s42834-024-00221-1","type":"published","date":"2024-07-15T16:05:13+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":51685912,"identity":"8bd38331-2455-4c8c-91ad-53dba6c300f9","added_by":"auto","created_at":"2024-02-27 08:21:11","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":23504,"visible":true,"origin":"","legend":"\u003cp\u003eOxidation pathway of FBSE involving its aldehyde, aldehyde hydration, leading to FBSAA\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-3928681/v1/882c712170a316b6b3444f9a.png"},{"id":51685910,"identity":"18512373-b590-49e2-ba77-24d353a802fc","added_by":"auto","created_at":"2024-02-27 08:21:11","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":47622,"visible":true,"origin":"","legend":"\u003cp\u003eFBSA-PrNO\u003csub\u003e2\u003c/sub\u003e and FBSE-Am are isomers with distinct polar head groups, presenting sulfonamide and sulfonamido ethanol\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-3928681/v1/dd44ec2d9263938aa5065504.png"},{"id":51685911,"identity":"16b464b8-4165-4377-8b7d-7f08c9a8c08e","added_by":"auto","created_at":"2024-02-27 08:21:11","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":91328,"visible":true,"origin":"","legend":"\u003cp\u003eMS2 spectra of E-FBSE and FBSAcAL hydrate as polar-head isomers\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-3928681/v1/2b671bf41ec1dfe0ec56ee53.png"},{"id":51685913,"identity":"e3738fa1-68ac-4042-bcb0-7d7cf47624af","added_by":"auto","created_at":"2024-02-27 08:21:11","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":39967,"visible":true,"origin":"","legend":"\u003cp\u003eMeFBSAA and FBSPrA, as polar head isomers, exhibit differences in the number of carbons in the sulfonamido carboxylic acid.\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-3928681/v1/db021c730bb636508f1e79cf.png"},{"id":61595100,"identity":"6dd9a215-20c3-4bbf-8c5b-5a8d1fa1930f","added_by":"auto","created_at":"2024-08-01 17:20:00","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1486650,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-3928681/v1/729e24ef-79de-435b-8f11-0c16a2af22e8.pdf"},{"id":51685914,"identity":"afe22cf7-ea26-4c02-92d6-7d293ad6aa78","added_by":"auto","created_at":"2024-02-27 08:21:12","extension":"docx","order_by":6,"title":"","display":"","copyAsset":false,"role":"supplement","size":6606595,"visible":true,"origin":"","legend":"","description":"","filename":"SI0131SER.docx","url":"https://assets-eu.researchsquare.com/files/rs-3928681/v1/944038543584470ccad9675f.docx"}],"financialInterests":"","formattedTitle":"Comprehensive Nontargeted Analysis of Fluorosurfactant Byproducts and Reaction Products in Wastewater from Semiconductor Manufacturing","fulltext":[{"header":"Introduction","content":"\u003cp\u003ePerfluoroalkyl and polyfluoroalkyl substances (PFAS) have been extensively utilized in various industrial processes and commercial products, including food packaging, stain repellents, building materials, electronic devices, and firefighting foams. [\u003cspan additionalcitationids=\"CR2\" citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e] The OECD's 2021 revision of the PFAS definition expands the range of fluorochemicals, classifying PFAS as fluorinated substances with at least one fully fluorinated methyl or methylene carbon atom (without any H/Cl/Br/I atom attached).[\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e] PFAS, with fluorine-substituted aliphatic carbon backbones, exhibit stability, low refractive index, and hydrophobic/oleophobic properties,[\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e] making them valuable for industrial surfactants.[\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e] PFAS have aroused concern owing to their health [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e] and environmental impact. [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e] Under TSCA Section 8(a)(7), the USEPA mandates reporting regulations for PFAS in 2023, requiring manufacturers and processors to submit detailed information on PFAS substance usage from 2011 to 2022, covering identification, applications, quantities, environmental impacts, and health effects.[\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e] PFHxS including its salts and PFHxS-related compounds, have been listed in the Stockholm Convention to restrict and eliminate their use since 2022. Over one hundred PFHxS-related compounds, defined as structures containing C\u003csub\u003e6\u003c/sub\u003eF\u003csub\u003e13\u003c/sub\u003e capable of degrading into PFHxS, have been listed in the convention. A significant portion of these structures belongs to sulfonamides and sulfonamido substances, such as C\u003csub\u003e6\u003c/sub\u003eF\u003csub\u003e13\u003c/sub\u003eS(O\u003csub\u003e2\u003c/sub\u003e)N-R (sulfonamides) and C\u003csub\u003e6\u003c/sub\u003eF\u003csub\u003e13\u003c/sub\u003eS(O\u003csub\u003e2\u003c/sub\u003e)O-R (sulfonate) and C\u003csub\u003e6\u003c/sub\u003eF\u003csub\u003e13\u003c/sub\u003eS(O\u003csub\u003e2\u003c/sub\u003e)-R (sulfones), which release PFHxS after undergo degradation in the environment. [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e] [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. Despite the convention's recommendation to use total oxidable precursors (TOPs)[\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e, \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e] and extractable organic fluorine (EOF)[\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e] for precursor identification, standardized methods for individual compounds are currently unavailable. [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]\u003c/p\u003e \u003cp\u003eTo identify nontarget PFAS, high-resolution tandem mass spectrometry has been used widely in contaminated soil,[\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e, \u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e] surface water, [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e, \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e], wastewater from a fluorochemical manufacturing, [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e], and municipal wastewater,[\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e]. Mass defect and homologous patterns are potent tools for uncovering PFAS within a series of homologous substances. However, the chemicals employed in industrial processes exhibit diverse and precise functionalizations, making homologues less likely to occur in industrial manufacturing. Moreover, the intricate blend of industrial chemicals in sewage may undergo diverse reactions, such as hydration, oxidation and deamination. [\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e],\u003csup\u003e,\u003c/sup\u003e[\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e, \u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e] As these reactions occur in the polar functional section, each transformation leads to distinct mass defect values, making the use of homologous patterns for screening impractical. Consequently, our research employed a fragment-based approach to investigate PFAS-related substances by screening the polar functional groups and nonpolar fluoroalkyl chains of fluorosurfactants. Ten sewage samples from five semiconductor plants and three effluents from their associated wastewater treatment plants (WWTPs) were investigated for comprehensive identifications of PFAS-related byproducts of chemical formulations, transformation products generated during the oxidation process, and diverse reaction products generated from the intricate processes of semiconductor manufacturing.\u003c/p\u003e"},{"header":"Materials and methods","content":"\u003cp\u003eTable \u003cspan refid=\"MOESM1\" class=\"InternalRef\"\u003eS1\u003c/span\u003e lists authentic reference standards used to establish the patterns for scanning fragmentation and neutral loss values in PFAS screening.. The Table S2 includes lists of authentic reference standards employed to confirm the identified PFAS.\u003c/p\u003e \u003cp\u003eIn November 2020 and January 2021, ten sewage samples (no. 184\u0026ndash;187, 190, 191, 194\u0026ndash;197) were collected from five semiconductor plants situated in three different Science Parks, along with three effluent samples (WWTP3, WWTP4, WWTP5) from their respective wastewater treatment plants, as depicted in Figure \u003cspan refid=\"MOESM1\" class=\"InternalRef\"\u003eS1\u003c/span\u003e. The samples were kept in 1 L polypropylene bottles and sent to the laboratory at 4\u0026deg;C for analysis. For nontarget analysis, a solid phase extraction cartridge (Oasis WAX, Waters) features a weak anion-exchange and reversed-phased sorbent was applied to condense water samples. The capture strategy involves performing the load and wash procedures at pH\u0026thinsp;\u0026lt;\u0026thinsp;3. The elution is performed at a neutral pH for neutral PFAS and at a pH\u0026thinsp;\u0026gt;\u0026thinsp;8 for acidic PFAS. Detailed pretreatment procedures are included in the SI. The injection of a 50\u0026ndash;100 \u0026micro;L extract was carried out using a UPHLC binary pump system and interfaced with a negative electrospray ionization source coupled to a Q-Exactive hybrid mass spectrometer. The mass spectrometric analysis was conducted in full MS and 20 data-dependent MS2 scans, involving a full scan analysis ranging from m/z 77-1155 with applied fragmentation energy (NCE 15 and 50). Mass calibration before each analysis ensured accurate results, and the inclusion of acetic acid in the calibration solution is crucial to enhance mass accuracy, especially for low mass measurements. Specific details regarding the LC gradient program and mass spectrometry settings can be found in Table S3. Thermo Scientific Compound Discoverer 3.3 software was employed for compound detection and identification, with identification confidence levels (CLs) adapted from Charbonnet's classification.[\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e] In particular, the Compound Class Scoring node (MS2) and the Search Neutral Losses node (MS2) were utilized for searching fragments and neutral losses, respectively, while the Search for ChemSpider node screened databases based on formulas within a 5 ppm mass tolerance (MS1). The detailed specifications of the workflow nodes are outlined in Table S4.\u003c/p\u003e"},{"header":"Results and discussion","content":"\u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003e3.1 Nontarget analysis of PFAS and identified classes\u003c/h2\u003e \u003cp\u003eScreening functional polar heads is crucial for identifying nontargeted PFAS without apparent fluorocarbon fragments and discovering various reaction products formed in the polar functional groups during the semiconductor manufacturing. Nontarget identification is time-consuming and requires a harsh learning curve. Hence, we have streamlined the approach by summarizing the identified surfactant PFAS search through fragment and neutral loss screening of polar functional groups for the 12 classes with distinct polar functional groups, as shown in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e for sulfonamido substances and Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e for fluoroalkyl acids. This strategy uniquely emphasizes the neutral loss of segments such as SO\u003csub\u003e3\u003c/sub\u003e, CONH, CH\u003csub\u003e3\u003c/sub\u003eOH, and H\u003csub\u003e2\u003c/sub\u003eO for miscellaneous FASAs and FASEs, highlighting its novelty in identifying reaction products reported for the first time. In addition, our study leads the way in developing neutral loss screens for CO\u003csub\u003e2\u003c/sub\u003e, HFCO\u003csub\u003e2\u003c/sub\u003e, C\u003csub\u003en\u003c/sub\u003eH\u003csub\u003e2n\u003c/sub\u003eCO\u003csub\u003e2\u003c/sub\u003e, etc., serving as indicators to distinguish classes such as carboxylic acid, dicarboxylic acid, and sulfonamido carboxylic acid, each characterized by terminal carboxylate structures. A list of the 80 identified PFAS and their formula, retention time, precursor ion, and theoretical m/z are provided in Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e. The following is a discussion of the identified results for the 12 classes with distinct polar functional groups.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eProposed strategies of fragmentation and neutral loss of sulfonamides and sulfonamido substances identified in this study\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"7\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNo.\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eClass\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eHydrophilic group\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eSubclass\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eFragment 1 (m/z)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eFragment 2 (m/z)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003eNeutral loss (m/z)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eSulfonamides\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e-SO\u003csub\u003e2\u003c/sub\u003eN(X)H\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003ePer-and polyfluoroalkyl sulfonamides\u003csup\u003e1\u003c/sup\u003e (X\u0026thinsp;=\u0026thinsp;H) and miscellaneous FASAs (X\u0026thinsp;=\u0026thinsp;SO\u003csub\u003e3\u003c/sub\u003eH, CONH\u003csub\u003e2\u003c/sub\u003e, CH\u003csub\u003e2\u003c/sub\u003eNO\u003csub\u003e2\u003c/sub\u003e, etc.)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eSO\u003csub\u003e2\u003c/sub\u003eN\u003csup\u003e\u0026ndash;\u003c/sup\u003e (77.9644)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e[X-H]\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e-SO\u003csub\u003e2\u003c/sub\u003eN(R')H\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eN-Alkyl FASAs\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eSO\u003csub\u003e2\u003c/sub\u003eH\u003csup\u003e\u0026ndash;\u003c/sup\u003e (64.9697)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eSO\u003csub\u003e2\u003c/sub\u003eF\u003csup\u003e\u0026ndash;\u003c/sup\u003e (82.9603)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eSulfonamido ethanols\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e-SO\u003csub\u003e2\u003c/sub\u003eN(X)CH\u003csub\u003e2\u003c/sub\u003eCH\u003csub\u003e2\u003c/sub\u003eOH\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003ePer- and polyfluoroalky sulfonamido ethanol (FASEs (X\u0026thinsp;=\u0026thinsp;H) and miscellaneous FASEs (X\u0026thinsp;=\u0026thinsp;SO\u003csub\u003e3\u003c/sub\u003eH, CONH\u003csub\u003e2\u003c/sub\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eSO\u003csub\u003e2\u003c/sub\u003eH\u003csup\u003e\u0026ndash;\u003c/sup\u003e (64.9697)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eSO\u003csub\u003e2\u003c/sub\u003eNC\u003csub\u003e2\u003c/sub\u003eH\u003csub\u003e4\u003c/sub\u003eO\u003csup\u003e\u0026ndash;\u003c/sup\u003e (121.9912)\u003c/p\u003e \u003cp\u003eSO\u003csub\u003e2\u003c/sub\u003eNCH\u003csub\u003e2\u003c/sub\u003e\u003csup\u003e\u0026ndash;\u003c/sup\u003e (91.9806)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e[X-H]\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e-SO\u003csub\u003e2\u003c/sub\u003eN(R')CH\u003csub\u003e2\u003c/sub\u003eCH\u003csub\u003e2\u003c/sub\u003eOH\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eN-Alkyl FASEs\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eCH\u003csub\u003e3\u003c/sub\u003eCO\u003csub\u003e2\u003c/sub\u003e\u003csup\u003e\u0026ndash;\u003c/sup\u003e (59.0139)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSulfonamido diethanols\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e-SO\u003csub\u003e2\u003c/sub\u003eN(CH\u003csub\u003e2\u003c/sub\u003eCH\u003csub\u003e2\u003c/sub\u003eOH)\u003csub\u003e2\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eN,N-bis(2-hydroxyethyl) per- and polyfluoroalkane sulfonamide (FASEE diol)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eSO\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e\u0026ndash;\u003c/sup\u003e (79.9563)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eSO\u003csub\u003e2\u003c/sub\u003eN(C\u003csub\u003e2\u003c/sub\u003eH\u003csub\u003e4\u003c/sub\u003eO)\u003csub\u003e2\u003c/sub\u003e\u003csup\u003e\u0026ndash;\u003c/sup\u003e (166.0179)\u003c/p\u003e \u003cp\u003eSO\u003csub\u003e2\u003c/sub\u003eN(C\u003csub\u003e2\u003c/sub\u003eH\u003csub\u003e4\u003c/sub\u003e)CH\u003csub\u003e2\u003c/sub\u003e\u003csup\u003e\u0026ndash;\u003c/sup\u003e (136.00739)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003e4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eSulfonamido carboxylic acids\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e-SO\u003csub\u003e2\u003c/sub\u003eN(H)C\u003csub\u003en\u003c/sub\u003eH\u003csub\u003e2n\u003c/sub\u003eCO\u003csub\u003e2\u003c/sub\u003eH\u003csup\u003e2\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003ePer- and polyfluoroalkane\u003csup\u003e3\u003c/sup\u003e carboxylic acid (FASCAs)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eSO\u003csub\u003e2\u003c/sub\u003eN\u003csup\u003e\u0026ndash;\u003c/sup\u003e (77.9644)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eSO\u003csub\u003e2\u003c/sub\u003eF\u003csup\u003e\u0026ndash;\u003c/sup\u003e (82.9603)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eC\u003csub\u003en\u003c/sub\u003eH\u003csub\u003e2n\u003c/sub\u003eCO\u003csub\u003e2\u003c/sub\u003e\u003csup\u003e2,3\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e-SO\u003csub\u003e2\u003c/sub\u003eN(R')CH\u003csub\u003e2\u003c/sub\u003eCOOH\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eN-Alkyl FASAAs\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eSO\u003csub\u003e2\u003c/sub\u003eF\u003csup\u003e\u0026ndash;\u003c/sup\u003e (82.9603)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eCH\u003csub\u003e2\u003c/sub\u003eCO\u003csub\u003e2\u003c/sub\u003e (58.0055)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSulfonamido diacetic acids\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e-SO\u003csub\u003e2\u003c/sub\u003eN(CH\u003csub\u003e2\u003c/sub\u003eCOOH)\u003csub\u003e2\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003ePer- and polyfluoroalkyl sulfonamido diacetic acid (FASEE diacid)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eSO\u003csub\u003e2\u003c/sub\u003eF\u003csup\u003e\u0026ndash;\u003c/sup\u003e (82.9603)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eCH\u003csub\u003e2\u003c/sub\u003eCO\u003csub\u003e2\u003c/sub\u003e (58.0055)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eN-ethylhydroxyl sulfonamido acetic acids\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e-SO\u003csub\u003e2\u003c/sub\u003eN(CH\u003csub\u003e2\u003c/sub\u003eCH\u003csub\u003e2\u003c/sub\u003eOH)\u003c/p\u003e \u003cp\u003eCH\u003csub\u003e2\u003c/sub\u003eCOOH\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eN-(2-hydroxyethyl) perfluoroalkane sulfonamido acetic acid (FASEE mono-ol monoacid)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eSO\u003csub\u003e2\u003c/sub\u003eF\u003csup\u003e\u0026ndash;\u003c/sup\u003e (82.9603)\u003c/p\u003e \u003cp\u003eSO\u003csub\u003e2\u003c/sub\u003eH\u003csup\u003e\u0026ndash;\u003c/sup\u003e (64.9697)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eSO\u003csub\u003e2\u003c/sub\u003eNC\u003csub\u003e2\u003c/sub\u003eH\u003csub\u003e4\u003c/sub\u003eO\u003csup\u003e\u0026ndash;\u003c/sup\u003e (121.9912)\u003c/p\u003e \u003cp\u003eSO\u003csub\u003e2\u003c/sub\u003eNCH\u003csub\u003e2\u003c/sub\u003e\u003csup\u003e\u0026ndash;\u003c/sup\u003e (91.9806)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eCH\u003csub\u003e2\u003c/sub\u003eCO\u003csub\u003e2\u003c/sub\u003e (58.0055)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSulfonamido acetaldehyde\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e-SO\u003csub\u003e2\u003c/sub\u003eNHCH\u003csub\u003e2\u003c/sub\u003eCOH\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003ePer- and polyfluoroalkyl sulfonamido acetaldehyde (FASAceAL)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eSO\u003csub\u003e2\u003c/sub\u003eH\u003csup\u003e\u0026ndash;\u003c/sup\u003e (64.9697)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eSO\u003csub\u003e2\u003c/sub\u003e\u003csup\u003e\u0026ndash;\u003c/sup\u003e (63.96245)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSulfonamido acetaldehyde hydrate/hemiacetal\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e-SO\u003csub\u003e2\u003c/sub\u003eNHCH\u003csub\u003e2\u003c/sub\u003eCH(OH)(OX)\u003c/p\u003e \u003cp\u003e(X\u0026thinsp;=\u0026thinsp;H (hydrate); X\u0026thinsp;=\u0026thinsp;CH\u003csub\u003e3\u003c/sub\u003e (hemiacetal))\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003ePer- and polyfluoroalkyl sulfonamido acetaldehyde (FASAceAL hyrate/hemiacetal)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eSO\u003csub\u003e2\u003c/sub\u003eH\u003csup\u003e\u0026ndash;\u003c/sup\u003e (64.9697)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eSO\u003csub\u003e2\u003c/sub\u003e\u003csup\u003e\u0026ndash;\u003c/sup\u003e (63.96245)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eH\u003csub\u003e2\u003c/sub\u003eO (18.0106)\u003c/p\u003e \u003cp\u003eMeOH (32.0262)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"7\"\u003e1: This subclass does not include fluorotelomer sulfonamides. In the series of fluorotelomer sulfonamides, the characteristic fragment is H\u003csub\u003e2\u003c/sub\u003eNSO\u003csub\u003e2\u003c/sub\u003e\u003csup\u003e\u0026ndash;\u003c/sup\u003e[\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e, \u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e], introduced by the significant presence of hydrogens in the fluorotelomer. However, the fluorotelomer series was not detected in this study; additional information for exclusion purposes is provided.\u003c/td\u003e\u003c/tr\u003e \u003ctr\u003e\u003ctd colspan=\"7\"\u003e2: The neutral loss of sulfonamido carboxylic acid is C\u003csub\u003en\u003c/sub\u003eH\u003csub\u003e2n\u003c/sub\u003eCO\u003csub\u003e2\u003c/sub\u003e, exemplified by sulfonamido acetic acid (58.0055) and sulfonamido propanoic acid (72.02113).\u003c/td\u003e\u003c/tr\u003e \u003ctr\u003e\u003ctd colspan=\"7\"\u003e3: The distinct neutral loss of CH\u003csub\u003e2\u003c/sub\u003eCO\u003csub\u003e2\u003c/sub\u003e might be affected by the significant presence of hydrogens in the fluorotelomer, resulting in the neutral loss of HF instead [\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e] However, the fluorotelomer series was not detected in this study; additional information for exclusion purposes is provided.\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eProposed strategies of fragmentation and neutral loss of per- and polyfluoroalkyl acids (PFAAs) identified in this study\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"7\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNo.\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eClass\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eHydrophilic group\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eSubclass\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eFragment 1 (m/z)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eFragment 2 (m/z)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003eNeutral loss (m/z)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eCarboxylic acids\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e-COOH\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003ePerfluoroalkyl carboxylic acids (PFCAs); Unsaturated PFCAs (U-PFCAs); Unsaturated perfluoroalkyl ether carboxylic acids (U-E-PFCAs)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eCO\u003csub\u003e2\u003c/sub\u003e (43.9893)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eHydro substituted PFCAs (H-PFCAs); Hydro substituted E-PFCAs (H\u003csub\u003en\u003c/sub\u003e-E-PFCAs)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eCO\u003csub\u003e2\u003c/sub\u003eHF (63.9961)\u003c/p\u003e \u003cp\u003eCO\u003csub\u003e2\u003c/sub\u003e (43.9893)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003ePerfluoroalkyl ether carboxylic acids (E-PFCAs)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eNot detected\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e10\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eDicarboxylic acid\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e-(COOH)\u003csub\u003e2\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003ePerfluoroalkyl dicarboxylic acids (PFdiCAs)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eCO\u003csub\u003e2\u003c/sub\u003e (43.9893)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e11\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSulfonic acid\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e-SO\u003csub\u003e3\u003c/sub\u003eH\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003ePerfluoroalkane sulfonic acids (PFSAs)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eSO\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e\u0026ndash;\u003c/sup\u003e (79.9563)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eSO\u003csub\u003e3\u003c/sub\u003eF\u003csup\u003e\u0026minus;\u003c/sup\u003e (98.9547)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eHydro substituted PFSAs (H-PFSAs)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eSO\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e\u0026minus;\u003c/sup\u003e (79.9563)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eHF (20.0062)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eHydro substituted and ether PFSAs (H\u003csub\u003en\u003c/sub\u003e-E-PFSAs)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eSO\u003csub\u003e3\u003c/sub\u003eH\u003csup\u003e\u0026ndash;\u003c/sup\u003e (80.96519)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eSO\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e\u0026minus;\u003c/sup\u003e (79.9563)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eHF (20.0062)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e12\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSulfinic acid\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e-SO\u003csub\u003e2\u003c/sub\u003eH\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003ePerfluoroalkyl sulfinic acid\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eSO\u003csub\u003e2\u003c/sub\u003eF\u003csup\u003e\u0026ndash;\u003c/sup\u003e (82.9603)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eIdentified PFAS categorized by polar head class, subclass, theoretical precursor ion, retention time (RT), confidence level (CL), and first report.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"9\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c9\" colnum=\"9\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eClass\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e \u003cp\u003eSubclass\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eAberration\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eRT (min)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003eTheoretical ion (m/z)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c8\"\u003e \u003cp\u003eCL\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c9\"\u003e \u003cp\u003eFirst report\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSulfonamides\u003c/p\u003e \u003cp\u003e\u003cem\u003e\u0026ndash;SO\u003c/em\u003e\u003csub\u003e\u003cem\u003e2\u003c/em\u003e\u003c/sub\u003e\u003cem\u003eNH\u003c/em\u003e\u003csub\u003e\u003cem\u003e2\u003c/em\u003e\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003ePerfluoroalkane sulfonamides (FASAs)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eFBSA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e21.97\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e297.95897\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e1a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eHydro-substituted perfluoroalkyl sulfonamides (H-FASAs)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eH-FBSA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e10.69\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e279.96840\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e3a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eV\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1c\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003ePerfluoroalkyl ether sulfonamides (E-FASAs)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eE-FBSA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e25.91(1)\u003c/p\u003e \u003cp\u003e27.37(2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e313.95389\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e2b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eV\u003c/p\u003e \u003cp\u003eV\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\" morerows=\"2\" rowspan=\"3\"\u003e \u003cp\u003eMiscellaneous sulfonamides\u003c/p\u003e \u003cp\u003e\u003cem\u003e\u0026ndash;SO\u003c/em\u003e\u003csub\u003e\u003cem\u003e2\u003c/em\u003e\u003c/sub\u003e\u003cem\u003eN(X)H\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1d\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eX:SO\u003csub\u003e3\u003c/sub\u003eH\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eFBSA-SO\u003csub\u003e3\u003c/sub\u003eH\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e3.58\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e377.91579\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e2b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eV\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eX:CONH\u003csub\u003e2\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eFBSA-Am\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e8.72\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e340.96479\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e2b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eV\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1f\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eX:CH\u003csub\u003e2\u003c/sub\u003eCONH\u003csub\u003e2\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eFBSA-MeAm\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e10.72\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e354.98044\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e3a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eV\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1g\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eX:CH\u003csub\u003e2\u003c/sub\u003eNO\u003csub\u003e2\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eFBSA-MeNO\u003csub\u003e2\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e7.28\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e356.95970\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e3a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eV\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1h\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eX:C\u003csub\u003e3\u003c/sub\u003eH\u003csub\u003e6\u003c/sub\u003eNO\u003csub\u003e2\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eFBSA-PrNO\u003csub\u003e2\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e8.81\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e384.99100*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e3a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eV\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1i\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eX:CH\u003csub\u003e2\u003c/sub\u003eN\u003csub\u003e2\u003c/sub\u003eH\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eFBSA-diazene\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e22.28\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e339.98077\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e3a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eV\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cem\u003eN-alkyl sulfonamides\u003c/em\u003e\u003c/p\u003e \u003cp\u003e\u003cem\u003e\u0026ndash;SO\u003c/em\u003e\u003csub\u003e\u003cem\u003e2\u003c/em\u003e\u003c/sub\u003e\u003cem\u003eN(R\u0026rsquo;)H\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1j\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eN-methyl perfluoroalkane sulfonamides (MeFASAs) R\u0026thinsp;=\u0026thinsp;CH\u003csub\u003e3\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eMeFBSA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e36.77\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e311.97462\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e1a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSulfonamido ethanols\u003c/p\u003e \u003cp\u003e\u003cem\u003e\u0026ndash;SO\u003c/em\u003e\u003csub\u003e\u003cem\u003e2\u003c/em\u003e\u003c/sub\u003e\u003cem\u003eN(H)CH\u003c/em\u003e\u003csub\u003e\u003cem\u003e2\u003c/em\u003e\u003c/sub\u003e\u003cem\u003eCH\u003c/em\u003e\u003csub\u003e\u003cem\u003e2\u003c/em\u003e\u003c/sub\u003e\u003cem\u003eOH\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003ePerfluoroalkane sulfonamido ethanols (FASEs)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eFEtSE\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e9.46\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e241.99158\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e2b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eFPrSE\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e18.47\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e291.98838\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e2b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eFBSE\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e30.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e341.98519\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e1b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eHydro substituted perfluoroalkane sulfonamido ethanols (H-FASEs)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eH-FBSE\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e15.84\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e323.99461\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e3a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eV\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2c\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003ePerfluoroalkyl ether sulfonamido ethanols (E-FASEs)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eE-FBSE\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e33.94 (1)\u003c/p\u003e \u003cp\u003e34.28 (2)\u003c/p\u003e \u003cp\u003e35.10 (3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e357.98010\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e2b\u003c/p\u003e \u003cp\u003e2b\u003c/p\u003e \u003cp\u003e2b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eV\u003c/p\u003e \u003cp\u003eV\u003c/p\u003e \u003cp\u003eV\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2d\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eHydrogen substituted perfluoroalkyl ether sulfonamido ethanols (E-H-FASEs)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eH-E-FBSE\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e21.41\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e339.98952\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e3a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eV\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eUnsaturated perfluoroalkyl sulfonamido ethanols (U-FASEs)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eU-FBSE\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e16.76\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e303.98838\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e3a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eV\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2f\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eunsaturated perfluoroalkyl ether sulfonamido ethanols (U-E-FASEs)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eU-E-FBSE\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e23.78\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e319.98330\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e3a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eV\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eMiscellaneous sulfonamido ethanols\u003c/p\u003e \u003cp\u003e\u003cem\u003e\u0026ndash;SO\u003c/em\u003e\u003csub\u003e\u003cem\u003e2\u003c/em\u003e\u003c/sub\u003e\u003cem\u003eN(X)CH\u003c/em\u003e\u003csub\u003e\u003cem\u003e2\u003c/em\u003e\u003c/sub\u003e\u003cem\u003eCH\u003c/em\u003e\u003csub\u003e\u003cem\u003e2\u003c/em\u003e\u003c/sub\u003e\u003cem\u003eOH\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2g\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eX:SO\u003csub\u003e3\u003c/sub\u003eH\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eFBSE-SO\u003csub\u003e3\u003c/sub\u003eH\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e17.79\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e421.94200\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e2b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eV\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2h\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eX:CONH\u003csub\u003e2\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eFBSE-Am\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e29.97\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e384.99100*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e2b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eV\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eN-alkyl sulfonamido ethanols\u003c/p\u003e \u003cp\u003e\u0026ndash;SO\u003csub\u003e2\u003c/sub\u003eN(R\u0026rsquo;) \u003cem\u003eCH\u003c/em\u003e\u003csub\u003e\u003cem\u003e2\u003c/em\u003e\u003c/sub\u003e\u003cem\u003eCH\u003c/em\u003e\u003csub\u003e\u003cem\u003e2\u003c/em\u003e\u003c/sub\u003e\u003cem\u003eOH\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2i\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eN-methyl perfluoroalkane sulfonamido ethanols (MeFASEs) R\u0026thinsp;=\u0026thinsp;CH\u003csub\u003e3\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eMeFBSE\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e35.21\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e416.02197\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e1a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eV\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e293\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSulfonamido diethanols\u003c/p\u003e \u003cp\u003e\u003cem\u003e\u0026ndash;SO\u003c/em\u003e\u003csub\u003e\u003cem\u003e2\u003c/em\u003e\u003c/sub\u003e\u003cem\u003eN(CH\u003c/em\u003e\u003csub\u003e\u003cem\u003e2\u003c/em\u003e\u003c/sub\u003e\u003cem\u003eCH\u003c/em\u003e\u003csub\u003e\u003cem\u003e2\u003c/em\u003e\u003c/sub\u003e\u003cem\u003eOH)\u003c/em\u003e\u003csub\u003e\u003cem\u003e2\u003c/em\u003e\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eN,N-bis(2-hydroxyethyl) perfluoroalkane sulfonamides (FASEE diols)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eFBSEE\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e31.52\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e386.01140\u003c/p\u003e \u003cp\u003e446.03253\u003c/p\u003e \u003cp\u003e432.01688\u003c/p\u003e \u003cp\u003e773.03008\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e1a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eHydro-substituted FASEE diol (H-FASEE diols)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eH-FBSEE\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e16.96\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e428.04195\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e2b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eV\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eSulfonamido carboxylic acids\u003c/p\u003e \u003cp\u003e\u0026ndash;\u003cem\u003eSO\u003c/em\u003e\u003csub\u003e\u003cem\u003e2\u003c/em\u003e\u003c/sub\u003e\u003cem\u003eNH(CH\u003c/em\u003e\u003csub\u003e\u003cem\u003e2\u003c/em\u003e\u003c/sub\u003e\u003cem\u003e)\u003c/em\u003e\u003csub\u003e\u003cem\u003en\u003c/em\u003e\u003c/sub\u003e\u003cem\u003eCOOH\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eperfluoroalkane sulfonamido acetic acids (FASAAs)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eFBSAA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e9.93 (1)\u003c/p\u003e \u003cp\u003e15.50 (2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e355.96445\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e1b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eV\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eHydro-substituted FASAAs (H-FASAAs)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eH-FBSAA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e7.29\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e337.97387\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e3a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eV\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4c\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003ePerfluoroalky ether sulfonamido acetic acids (E-FASAAs)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eE-FBSAA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e18.73 (1)\u003c/p\u003e \u003cp\u003e19.73 (2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e371.95937\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e3a\u003c/p\u003e \u003cp\u003e3a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eV\u003c/p\u003e \u003cp\u003eV\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4d\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eN-methyl FASAAs (N-MeFASAAs)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eN-MeFBSAA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e20.38\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e369.98120*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e1a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003ePerfluoroalkane sulfonamido propanoic acids (FASPrAs)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eN-FBSPrA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e19.06\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e369.98120*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e2b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eV\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSulfonamido diacetic acids\u003c/p\u003e \u003cp\u003e\u003cem\u003e\u0026ndash;SO\u003c/em\u003e\u003csub\u003e\u003cem\u003e2\u003c/em\u003e\u003c/sub\u003e\u003cem\u003eN(CH\u003c/em\u003e\u003csub\u003e\u003cem\u003e2\u003c/em\u003e\u003c/sub\u003e\u003cem\u003eCOOH)\u003c/em\u003e\u003csub\u003e\u003cem\u003e2\u003c/em\u003e\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e5a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eperfluoroalkane sulfonamido diacetic acids (FASEE diacids)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eFBSEE diacid\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e5.83\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e413.96993\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e2b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eN-ethylhydroxyl sulfonamido acetic acids\u003c/p\u003e \u003cp\u003e\u003cem\u003e\u0026ndash;SO\u003c/em\u003e\u003csub\u003e\u003cem\u003e2\u003c/em\u003e\u003c/sub\u003e\u003cem\u003eN (CH\u003c/em\u003e\u003csub\u003e\u003cem\u003e2\u003c/em\u003e\u003c/sub\u003e\u003cem\u003eCH\u003c/em\u003e\u003csub\u003e\u003cem\u003e2\u003c/em\u003e\u003c/sub\u003e\u003cem\u003eOH) (CH\u003c/em\u003e\u003csub\u003e\u003cem\u003e2\u003c/em\u003e\u003c/sub\u003e\u003cem\u003eCOOH)\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e6a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eN-(2-hydroxyethyl) perfluoroalkane sulfonamido acetic acids (FASEE mono-ol monoacid)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eFBSEE mono-ol monoacid\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e17.10\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e399.99067\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e2b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSulfonamido acetaldehyde\u003c/p\u003e \u003cp\u003e\u003cem\u003e\u0026ndash;SO\u003c/em\u003e\u003csub\u003e\u003cem\u003e2\u003c/em\u003e\u003c/sub\u003e\u003cem\u003eN(H)CH\u003c/em\u003e\u003csub\u003e\u003cem\u003e2\u003c/em\u003e\u003c/sub\u003e\u003cem\u003eCOH\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003ePerfluoroalkane sulfonamido acetaldehyde\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eFBSAcAL\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e13.03 (1)\u003c/p\u003e \u003cp\u003e30.03 (2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e339.96954\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e3a\u003c/p\u003e \u003cp\u003e3a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eV\u003c/p\u003e \u003cp\u003eV\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eSulfonamido acealdehyde hydrate/hemiacetal\u003c/p\u003e \u003cp\u003e\u003cem\u003e\u0026ndash;SO\u003c/em\u003e\u003csub\u003e\u003cem\u003e2\u003c/em\u003e\u003c/sub\u003e\u003cem\u003eN(H)CH\u003c/em\u003e\u003csub\u003e\u003cem\u003e2\u003c/em\u003e\u003c/sub\u003e\u003cem\u003eC (OH)(OR)H\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e8a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003ePerfluoroalkane sulfonamido acetaldehyde hydrate (R\u0026thinsp;=\u0026thinsp;H)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eFBSAcAL hydrate\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e32.63\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e357.98010\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e2b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eV\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e8b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003ePerfluoroalkane sulfonamido acetaldehyde hemiacetal\u003c/p\u003e \u003cp\u003e(R\u0026thinsp;=\u0026thinsp;CH\u003csub\u003e3\u003c/sub\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eFBSAcAL\u003c/p\u003e \u003cp\u003ehemiacetal\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e33.16\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e371.99575\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e2b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eV\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eCarboxylic acid\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e9a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\" morerows=\"9\" rowspan=\"10\"\u003e \u003cp\u003ePerfluoroalkyl carboxylic acids (PFCAs)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eTFA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e1.38\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e112.98559\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e1a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cem\u003e\u0026ndash;COOH\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003ePFPrA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e2.65\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e162.98239\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e1a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003ePFBA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e4.43\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e212.97920\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e1a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003ePFPeA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e8.15\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e262.97600\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e1a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003ePFHxA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e15.87\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e312.97281\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e1a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003ePFHpA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e25.52\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e362.96962\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e1a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003ePFOA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e35.28\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e412.96642\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e1a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003ePFNA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e45.98\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e462.96323\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e1a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003ePFDA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e54.82\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e512.96003\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e1a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003ePFUdA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e63.08\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e562.95684\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e1a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e9b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eUnsaturated PFCAs (U-PFCAs)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eU-PFHxA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e10.53\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e274.97600\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e3a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e9c\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\" morerows=\"2\" rowspan=\"3\"\u003e \u003cp\u003eUnsaturated-E-PFCAs (U-E-PFCAs)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eU-E-PFBA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e3.20\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e190.97731\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e3a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eU-E-PFPeA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e3.29 (1)\u003c/p\u003e \u003cp\u003e6.36 (2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e240.97411\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e3a\u003c/p\u003e \u003cp\u003e3a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eU-E-PFHxA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e3.66 (1)\u003c/p\u003e \u003cp\u003e5.80 (2)\u003c/p\u003e \u003cp\u003e11.07 (3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e290.97092\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e3a\u003c/p\u003e \u003cp\u003e3a\u003c/p\u003e \u003cp\u003e3a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e9d\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\" morerows=\"2\" rowspan=\"3\"\u003e \u003cp\u003eHydro-substituted PFCAs (H-PFCAs)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eH-PFBA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e3.23\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e194.98862\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e3a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eH-PFPeA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e4.74\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e244.98543\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e3a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eH-PFHxA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e9.35\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e294.98223\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e3a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e9e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eHydro-substituted E-PFCAs (H-E-PFCAs)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eH-E-PFPrA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e1.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e160.98673\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e3a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eH-E-PFBA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e3.13 (1)\u003c/p\u003e \u003cp\u003e3.77 (2)\u003c/p\u003e \u003cp\u003e9.83 (3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e210.98353\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e3a\u003c/p\u003e \u003cp\u003e3a\u003c/p\u003e \u003cp\u003e3a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eMultihydro-substituted E-PFCAs (H\u003csub\u003en\u003c/sub\u003e-E-PFCAs)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eH\u003csub\u003e2\u003c/sub\u003e-E-PFBA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e1.77\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e192.99296\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e3a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e9f\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\" morerows=\"2\" rowspan=\"3\"\u003e \u003cp\u003ePer- and polyfluoroalkyl ether carboxylic acids (E-PFCAs)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eE- PFPrA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e3.36\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e178.97731\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e3a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eE- PFBA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e5.82\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e228.97411\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e3a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eE- PFPeA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e10.14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e278.97092\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e3a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e10\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eDicarboxylic acid\u003c/p\u003e \u003cp\u003e\u003cem\u003e\u0026ndash;(COOH)\u003c/em\u003e\u003csub\u003e\u003cem\u003e2\u003c/em\u003e\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e10a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\" morerows=\"5\" rowspan=\"6\"\u003e \u003cp\u003ePerfluoroalkyl dicarboxylic acids (PFdiCAs)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003ePFdiCA(C3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e1.01\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e138.98484\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e3c\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003ePFdiCA(C4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e1.13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e188.98164\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e2c\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003ePFdiCA(C5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e1.18\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e238.97845\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e2c\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003ePFdiCA(C6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e1.25\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e288.97525\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e2b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003ePFdiCA(C7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e2.54\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e338.97206\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e3c\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003ePFdiCA(C8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e3.57\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e388.96887\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e2c\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e11\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\" morerows=\"2\" rowspan=\"3\"\u003e \u003cp\u003eSulfonic acid\u003c/p\u003e \u003cp\u003e\u003cem\u003e\u0026ndash;SO\u003c/em\u003e\u003csub\u003e\u003cem\u003e3\u003c/em\u003e\u003c/sub\u003e\u003cem\u003eH\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e11a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003ePerfluoroalkane sulfonic acids (PFSAs)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eTFMS\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e1.77\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e148.95257\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e1a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003ePFBS\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e9.83\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e298.94299\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e1a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e11b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\" morerows=\"2\" rowspan=\"3\"\u003e \u003cp\u003eHydro substituted PFSAs (H-PFSAs)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eH-PFEtS\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e1.91\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e180.95880\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e3a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eH-PFPrS\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e3.57\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e230.95560\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e3a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eH-PFBS\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e5.18\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e280.95241\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e3a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e11c\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eHydro substituted perfluoroalkyl ether sulfonic acids (H\u003csub\u003en\u003c/sub\u003e-E-PFSAs)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eH\u003csub\u003e2\u003c/sub\u003e-E-PFPrS\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e2.57\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e228.95994\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e3a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e12\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSulfinic acids\u003c/p\u003e \u003cp\u003e\u003cem\u003e\u0026ndash;SO\u003c/em\u003e\u003csub\u003e\u003cem\u003e2\u003c/em\u003e\u003c/sub\u003e\u003cem\u003eH\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e12\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003ePerfluoroalkyl sulfinic acids (PFSiA)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003ePFBSi\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e11.39\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e282.94807\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e1a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"9\"\u003e*: the presence of structural isomers in other subclasses\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cb\u003eClass 1 Sulfonamides\u003c/b\u003e By searching for NSO\u003csub\u003e2\u003c/sub\u003e\u003csup\u003e\u0026ndash;\u003c/sup\u003e fragment searching and excluding substances lacking fluorine based on isotopic formulas, we identified the predominant perfluoroalkane sulfonamides (FASAs) and various FASA series chemicals, resulting in the detection of 9 subclasses (1a-1i). Among them, 3 subclasses (1a-1c) displayed variations in the fluoroalkyl chain but had a polar head of -SO\u003csub\u003e2\u003c/sub\u003eNH\u003csub\u003e2\u003c/sub\u003e. This class, which features sulfonyl groups linked to amines (\u0026ndash;SO\u003csub\u003e2\u003c/sub\u003eNH\u003csub\u003e2\u003c/sub\u003e), exhibits a unique characteristic fragment, SO\u003csub\u003e2\u003c/sub\u003eN- (77.9644), which is observed in perfluorobutane sulfonamide (FBSA), hydro-substituted FBSA (H-FBSA), and ether FBSA (E-FBSA). Notably, no obvious fragmentations from the fluoroalkyl tail were detected during screening, suggesting that SO\u003csub\u003e2\u003c/sub\u003eN- is a feasible screening tool for identifying these subclasses. In Figure S3, the CL for H-FBSA reamined at 3a, reflecting uncertainty about the position of the hydrogen. E-FBSA, which has two isomers, was recognized by its specific ether fragments CF\u003csub\u003e3\u003c/sub\u003eO\u003csup\u003e\u0026minus;\u003c/sup\u003e(84.99067) and C\u003csub\u003e2\u003c/sub\u003eF\u003csub\u003e5\u003c/sub\u003eO\u003csub\u003e\u0026minus;\u003c/sub\u003e(134.98748) with an isotope pattern matching of C\u003csub\u003e4\u003c/sub\u003eF\u003csub\u003e9\u003c/sub\u003eH\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e3\u003c/sub\u003eSN (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e4\u003c/span\u003ea and \u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e4\u003c/span\u003eb) and the CL was set to 2b.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eThe remaining 6 subclasses (1d-1i) featured a fixed fluoroalkyl chain as perfluorobutane but showed variations in the functional group as -SO\u003csub\u003e2\u003c/sub\u003eN(X)H. The miscellaneous FASAs with the structure C\u003csub\u003e4\u003c/sub\u003eF\u003csub\u003e9\u003c/sub\u003eSO\u003csub\u003e2\u003c/sub\u003eNHX (X\u0026thinsp;=\u0026thinsp;SO\u003csub\u003e3\u003c/sub\u003eH; CONH\u003csub\u003e2\u003c/sub\u003e; CH\u003csub\u003e2\u003c/sub\u003eCONH\u003csub\u003e2\u003c/sub\u003e; CH\u003csub\u003e2\u003c/sub\u003eNO\u003csub\u003e2\u003c/sub\u003e; C\u003csub\u003e3\u003c/sub\u003eH\u003csub\u003e6\u003c/sub\u003eNO\u003csub\u003e2\u003c/sub\u003e; CH\u003csub\u003e2\u003c/sub\u003eN\u003csub\u003e2\u003c/sub\u003eH, subclass 1d-1i) were identified with the fragment of SO\u003csub\u003e2\u003c/sub\u003eN\u003csup\u003e\u0026minus;\u003c/sup\u003e (77.9644). Additional indicators of these subclasses were observed through the neutral loss of X-H, such as the subclass with a neutral loss of C\u003csub\u003e3\u003c/sub\u003eH\u003csub\u003e5\u003c/sub\u003eNO\u003csub\u003e2\u003c/sub\u003e (Figure S5), representing a novel screening approach for miscellaneous FASAs and being reported for the first time. Notably, in the presence of substances with N-alkyl substitutions, SO\u003csub\u003e2\u003c/sub\u003e\u003csup\u003e\u0026minus;\u003c/sup\u003e (63.9625) and SO\u003csub\u003e2\u003c/sub\u003eH\u003csup\u003e\u0026minus;\u003c/sup\u003e (64.9697) became dominant fragments and the weak fragment SO\u003csub\u003e2\u003c/sub\u003eF\u003csup\u003e\u0026minus;\u003c/sup\u003e (82.9603) was observed. N-Methyl perfluorobutane sulfonamide (MeFBSA) was identified in the effluents of WWTP3 and WWTP4 (Figure S6a). The confirmation of the authentic standard of MeFBSA resulted in setting the CL to 1 (Figure S6b). To the best of our knowledge, 9 identified PFAS (including 2 E-FBSA isomers) of these subclasses have been reported for the first time, as shown in Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e. Remarkably, fluorotelomer sulfonamides identified by other researchers are detected with the H\u003csub\u003e2\u003c/sub\u003eNSO\u003csub\u003e2\u003c/sub\u003e- fragment [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e, \u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e], distinguishing them from perfluoroalkane sulfonamides (FASAs), H-FASA, H-E-FASA, and U-FASA in our study, which exhibit the characteristic NSO\u003csub\u003e2\u003c/sub\u003e\u003csup\u003e\u0026ndash;\u003c/sup\u003e fragment. The introduction of the H2NSO\u003csub\u003e2\u003c/sub\u003e\u003csup\u003e\u0026ndash;\u003c/sup\u003e fragment is attributed to the substantial presence of hydrogens in the fluorotelomer.\u003c/p\u003e \u003cp\u003e \u003cb\u003eClass 2 Sulfonamido ethanols\u003c/b\u003e The class has a structure where sulfonamido is linked to a hydroxyethyl group, and its main characteristic fragments are SO\u003csub\u003e2\u003c/sub\u003eNC\u003csub\u003e2\u003c/sub\u003eH\u003csub\u003e4\u003c/sub\u003eO\u003csup\u003e\u0026ndash;\u003c/sup\u003e (121.9912) and SO\u003csub\u003e2\u003c/sub\u003eNCH\u003csub\u003e2\u003c/sub\u003e\u003csup\u003e\u0026ndash;\u003c/sup\u003e (91.9806). By conducting SO\u003csub\u003e2\u003c/sub\u003eNC\u003csub\u003e2\u003c/sub\u003eH\u003csub\u003e4\u003c/sub\u003eO\u003csup\u003e\u0026ndash;\u003c/sup\u003e and SO\u003csub\u003e2\u003c/sub\u003eNCH\u003csub\u003e2\u003c/sub\u003e\u003csup\u003e\u0026ndash;\u003c/sup\u003efragment searching and subseqently excluding substances lacking fluorine based on isotopic formulas, we identified the predominant perfluoroalkane sulfonamido ehtaol (FASEs) and miscellaneous FASE series, resulting in the detection of 8 subclasses (2a-2h). Among them, 6 subclasses (2a-2f) displaying variations in the fluoroalkyl chain were effectively identified, including perfluorobutane sulfonamido ethanol (FBSE), hydro-substituted perfluorobutane sulfonamido ethanol (H-FBSE), perfluorobutyl ether sulfonamido ehtanol (E-FBSE), hydro-substituted perfluorobutyl ether sulfonamido ehtanol (H-E-FBSE), unsaturated perfluorobutane sulfonamido ehtanol (U-FBSE), and unsaturated perfluorobutyl ether sulfonamido ehtanol (U-FBSE). Figure S7 displays the MS2 spectrum and proposed structure of hydro-substituted perfluorobutane sulfonamido ethanol (H-FBSE). The confidence level for H-FBSE remains at 3a due to uncertainties in identifying the position of hydrogen. Next, three isomers of perfluorobutyl ether sulfonamide ethanol (E-FBSE) were identified and three characteristic peaks from fragments CF\u003csub\u003e3\u003c/sub\u003eO\u003csup\u003e\u0026minus;\u003c/sup\u003e, C\u003csub\u003e3\u003c/sub\u003eF\u003csub\u003e7\u003c/sub\u003eO\u003csup\u003e\u0026minus;\u003c/sup\u003e, and C\u003csub\u003e2\u003c/sub\u003eF\u003csub\u003e5\u003c/sub\u003eO\u003csup\u003e\u0026minus;\u003c/sup\u003e were observed by chromatography, and their structures were proposed (Figure S8a, 8b, 8c) with a confidence level of 2b. The greater retention time (RT 35.13 min) of the E-FBSE isomer was indicative of the increased symmetry of the alkyl structure matching the proposed structure. The presence of hydrogen-substituted perfluorobutyl ether sulfonamido ethanols (H-E-FBSEs) with the specific fluoroalkyl ether fragment C\u003csub\u003e2\u003c/sub\u003eF\u003csub\u003e3\u003c/sub\u003eO\u003csup\u003e\u0026minus;\u003c/sup\u003e(96.99074, 0.72 ppm) was indicative of the loss of HF from C\u003csub\u003e2\u003c/sub\u003eF\u003csub\u003e4\u003c/sub\u003eHO\u003csup\u003e\u0026minus;\u003c/sup\u003e (116.99708, 1.54 ppm). U-FBSE with the fragment C\u003csub\u003e4\u003c/sub\u003eF\u003csub\u003e7\u003c/sub\u003e\u003csup\u003e\u0026minus;\u003c/sup\u003e(180.98955, 0.99 ppm) was detected. We proposed a confidence level of 3a due to the lack of further information to determine the position of the double bond. Unsaturated perfluoroalkyl ether sulfonamido ethanols (U-E-FASEs) with the specific fragments C\u003csub\u003e3\u003c/sub\u003eF\u003csub\u003e5\u003c/sub\u003e-(130.99281, 1.91 ppm) and C\u003csub\u003e4\u003c/sub\u003eF\u003csub\u003e7\u003c/sub\u003eO-(196.98503, 3.79 ppm) were detected, which suggested the position of the oxygen atom (Figure S9). However, the position of the unsaturated bond remained uncertain, so the confidence level was set to 3a. To the best of our knowledge, 5 subclasses (subclasses 2b-2f) of FASEs with various fluoroalkyl chains have been reported for the first time (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e). In addition, miscellaneous FBSEs with the structure C\u003csub\u003e4\u003c/sub\u003eF\u003csub\u003e9\u003c/sub\u003eSO\u003csub\u003e2\u003c/sub\u003eN(X)(C\u003csub\u003e2\u003c/sub\u003eH\u003csub\u003e4\u003c/sub\u003eOH) (X:SO\u003csub\u003e3\u003c/sub\u003eH; X:CONH\u003csub\u003e2\u003c/sub\u003e) were detected in subclasses 2g and 2h, identified through characteristic fragment SO\u003csub\u003e2\u003c/sub\u003eNC\u003csub\u003e2\u003c/sub\u003eH\u003csub\u003e4\u003c/sub\u003eO\u003csup\u003e\u0026ndash;\u003c/sup\u003e (121.9912) screening. Notably, subclasses 2g and 2h could be detected through neutral loss screening of SO\u003csub\u003e3\u003c/sub\u003e and CONH. (Figure S10)\u003c/p\u003e \u003cp\u003eTo explore the subclass (2i) of N-alkyl perfluoroalkane sulfonamido ethanol, we examined MeFOSE and EtFOSE with authentic standards, revealing characteristic MS2 spectra of this subclass. Both MeFOSE and EtFOSE displayed an acetate adduct [M\u0026thinsp;+\u0026thinsp;CH\u003csub\u003e3\u003c/sub\u003eCOO]\u003csup\u003e\u0026minus;\u003c/sup\u003e. In alkyl-substituted sulfonamido ethanol, no SO\u003csub\u003e2\u003c/sub\u003eNC\u003csub\u003e2\u003c/sub\u003eH\u003csub\u003e4\u003c/sub\u003eO\u003csup\u003e\u0026minus;\u003c/sup\u003e (121.9912) and SO\u003csub\u003e2\u003c/sub\u003eNCH\u003csub\u003e2\u003c/sub\u003e\u003csup\u003e\u0026minus;\u003c/sup\u003e (91.9806) fragments were observed; only CH\u003csub\u003e3\u003c/sub\u003eCOO\u003csup\u003e\u0026minus;\u003c/sup\u003e (59.01385) appeared. Screening of the acetate adduct of MeFBSE (416.02197) in sample no. 190 revealed fragments of SO\u003csub\u003e2\u003c/sub\u003eNC\u003csub\u003e2\u003c/sub\u003eH\u003csub\u003e4\u003c/sub\u003eO\u003csup\u003e\u0026minus;\u003c/sup\u003e (121.99250) and SO\u003csub\u003e2\u003c/sub\u003eH\u003csup\u003e\u0026minus;\u003c/sup\u003e (64.97031) at RT 35.82 (Fig.\u0026nbsp;11a). The MeFBSE in Sample no. 190, presumed to be branched, contained fragments of SO\u003csub\u003e2\u003c/sub\u003eNC\u003csub\u003e2\u003c/sub\u003eH\u003csub\u003e4\u003c/sub\u003eO\u003csup\u003e\u0026minus;\u003c/sup\u003e (121.99250) and SO\u003csub\u003e2\u003c/sub\u003eH\u003csup\u003e\u0026minus;\u003c/sup\u003e (64.97031), possibly distinct from the linear form of authentic standard (Fig.\u0026nbsp;11b). Owing to the lack of additional fragments, we assigned CL for MeFBSE as 1b due to insufficient isomeric data. Remarkably, fluorotelomer sulfonamido ethanol, such as 6:2 FTSAm-EtOH, which was identified by other researchers are detected, contains the SO\u003csub\u003e2\u003c/sub\u003eNC\u003csub\u003e2\u003c/sub\u003eH\u003csub\u003e4\u003c/sub\u003eO\u003csup\u003e\u0026minus;\u003c/sup\u003e (121.9912) fragment.[\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e] This fragment, elucidated as SO\u003csub\u003e2\u003c/sub\u003eNC\u003csub\u003e2\u003c/sub\u003eH\u003csub\u003e4\u003c/sub\u003eO\u003csup\u003e\u0026minus;\u003c/sup\u003e (121.9912), remains unaffected by the functional fluoroalkyl chain, including fluorotelemer, serving as a unique indicator of the class of sulfonamido ethanol.\u003c/p\u003e \u003cp\u003e \u003cb\u003eClass 3 Sulfonamido diethanol\u003c/b\u003e N,N-bis(2-hydroxyethyl)perfluorobutane sulfonamide (FBSEE diol) was identified and detected in the form of an acetate adduct [M\u0026thinsp;+\u0026thinsp;CH\u003csub\u003e3\u003c/sub\u003eCOO]\u003csup\u003e\u0026minus;\u003c/sup\u003e, [M-H]\u003csup\u003e\u0026minus;\u003c/sup\u003e, a formate adduct [M\u0026thinsp;+\u0026thinsp;HCOO]\u003csup\u003e\u0026minus;\u003c/sup\u003e, and a dimer ion [2M-H]\u003csup\u003e\u0026minus;\u003c/sup\u003e, in the order of their observed intensities (Figure S12). This structure exhibited characteristic fragments, including SO\u003csub\u003e2\u003c/sub\u003eN(C\u003csub\u003e2\u003c/sub\u003eH\u003csub\u003e4\u003c/sub\u003eO)\u003csub\u003e2\u003c/sub\u003e\u003csup\u003e\u0026minus;\u003c/sup\u003e, SO\u003csub\u003e2\u003c/sub\u003eN(C\u003csub\u003e2\u003c/sub\u003eH\u003csub\u003e4\u003c/sub\u003eO)CH\u003csub\u003e2\u003c/sub\u003e\u003csup\u003e\u0026minus;\u003c/sup\u003e, and SO\u003csub\u003e2\u003c/sub\u003eNC\u003csub\u003e2\u003c/sub\u003eH\u003csub\u003e4\u003c/sub\u003eO\u003csup\u003e\u0026minus;\u003c/sup\u003e. Additionally, the high-intensity SO\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e\u0026minus;\u003c/sup\u003e fragment serves as a confirming marker. FBSEE diol exhibited a weak characteristic fragment of the fluorobutyl fragment C\u003csub\u003e4\u003c/sub\u003eF\u003csub\u003e9\u003c/sub\u003e\u003csup\u003e\u0026minus;\u003c/sup\u003e, highlighting the feasibility of the screening method based on its functional group, as shown in Figure S13a and 13b. Hydrogen-substituted FBSEE diol (H-FBSEE diol) was detected with an acetate adduct and the unique fragment O\u003csub\u003e2\u003c/sub\u003eSN(C\u003csub\u003e2\u003c/sub\u003eH\u003csub\u003e4\u003c/sub\u003eO)\u003csub\u003e2\u003c/sub\u003e\u003csup\u003e\u0026minus;\u003c/sup\u003e (166.0174, -2.16 ppm) for the first time. The confidence level was set to 3a due to insufficient data to determine the position of hydrogen\u003c/p\u003e \u003cp\u003e \u003cb\u003eClass 4 Sulfonamido carboxylic acid\u003c/b\u003e This subclass features a structure with sulfonamido linked to a carboxylic acid group, releasing the carboxylic acid group during collision and producing characteristic fragments such as SO\u003csub\u003e2\u003c/sub\u003eN\u003csup\u003e\u0026minus;\u003c/sup\u003e (77.9644) and SO\u003csub\u003e2\u003c/sub\u003eF\u003csup\u003e\u0026minus;\u003c/sup\u003e (82.9603). A precursor ion at 355.96460, with a neutral loss of CH\u003csub\u003e2\u003c/sub\u003eCO\u003csub\u003e2\u003c/sub\u003e (-1.86 ppm), was identified as perfluorobutane sulfonamido acetic acid (FBSAA) (Figure S14a) and confirmed by its authentic standard at CL1 (Figure S14b). This series of compounds consistently exhibited a neutral loss of CH\u003csub\u003e2\u003c/sub\u003eCO\u003csub\u003e2\u003c/sub\u003e (58.00548 Da), demonstrating further identification of H-FBSAA (Figure S15), E-FBSAA, and N-methyl FBSAA (MeFBSAA) (Figure S16a). Perfluorobutyl ether sulfonamido acetic acid (E-FBSAA), which has two structural isomers, was separated with the column at retention times of 18.73 min and 19.73 min). Fragments of fluoroether CF\u003csub\u003e3\u003c/sub\u003eO\u003csup\u003e\u0026minus;\u003c/sup\u003e and C\u003csub\u003e2\u003c/sub\u003eF\u003csub\u003e5\u003c/sub\u003eO\u003csup\u003e\u0026minus;\u003c/sup\u003e were observed and providing the position of oxygen for the CL at 2b. MeFBSAA with isotope matching to C\u003csub\u003e7\u003c/sub\u003eH\u003csub\u003e6\u003c/sub\u003eF\u003csub\u003e9\u003c/sub\u003eNO\u003csub\u003e4\u003c/sub\u003eS (369.9790, -2.98 ppm) (Figure S16a) was confirmed by the matching RT and MS2 spectra of the authentic standards (Figure S16b). Notably, a structural isomer of MeFBSAA, C\u003csub\u003e7\u003c/sub\u003eH\u003csub\u003e6\u003c/sub\u003eF\u003csub\u003e9\u003c/sub\u003eNO\u003csub\u003e4\u003c/sub\u003eS (369.97022, -2.38 ppm), was identified for the first time as perfluorobutane sulfonamido propanoic acid (FBSPrA) (Figure S16). The neutral loss of C\u003csub\u003e2\u003c/sub\u003eH\u003csub\u003e4\u003c/sub\u003eCO\u003csub\u003e2\u003c/sub\u003e released from collision indicates propanoic acid. The presence of only SO\u003csub\u003e2\u003c/sub\u003eF\u003csup\u003e\u0026minus;\u003c/sup\u003e (82.9603) fragments, not SO\u003csub\u003e2\u003c/sub\u003eN\u003csup\u003e\u0026minus;\u003c/sup\u003e (77.9644), serves as a distinguishing rule between FASAA and N-alkyl FASAA. Notably, the distinct neutral loss of CH\u003csub\u003e2\u003c/sub\u003eCO\u003csub\u003e2\u003c/sub\u003e might be affected by the significant presence of hydrogens in the fluorotelomer, resulting in the neutral loss of HF instead [\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e]. However, the fluorotelomer series was not detected in this study; additional information for exclusion purposes is provided.\u003c/p\u003e \u003cp\u003e \u003cb\u003eClass 5 sulfonamido diacetic acid\u003c/b\u003e The MS2 spectrum of sulfonamido diacetic acid shows two pairs of neutral losses of CH\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e2\u003c/sub\u003e, indicating the presence of the diacetic acid structure. The main characteristic fragment was SO\u003csub\u003e2\u003c/sub\u003eF\u003csup\u003e\u0026minus;\u003c/sup\u003e (82.9603), while the intensity of SO\u003csub\u003e2\u003c/sub\u003eN\u003csup\u003e\u0026minus;\u003c/sup\u003e (77.9644) was notably weak. Perfluorobutane sulfonamido diacetic acid was identified with CL to 2b.[\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e]\u003c/p\u003e \u003cp\u003e \u003cb\u003eClass 6 N-hydroxyethyl sulfonamido acetic acid\u003c/b\u003e The substance with the precursor ion 399.9903 was identified by the specific fragment of O\u003csub\u003e2\u003c/sub\u003eSNC\u003csub\u003e2\u003c/sub\u003eH\u003csub\u003e4\u003c/sub\u003eO\u003csup\u003e\u0026minus;\u003c/sup\u003e (121.9912). The An obvious fragment 341.9852 was referred to as the FBSE fragment. The difference between 341.9852 and 399.9903 represents the neutral loss of CH\u003csub\u003e2\u003c/sub\u003eCO\u003csub\u003e2\u003c/sub\u003e. Consequently, we referred to this substance as N-(2-hydroxyethyl) perfluorobutane sulfonamido acetic acid (FBSEE mono-ol monoacid) at confidence level 2b.[\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e]\u003c/p\u003e \u003cp\u003e \u003cb\u003eClass 7 Sulfonamido acealdehyde\u003c/b\u003e The class with the structure where sulfonamido linked to acetaldehyde. C\u003csub\u003e6\u003c/sub\u003eH\u003csub\u003e3\u003c/sub\u003eF\u003csub\u003e9\u003c/sub\u003eNO\u003csub\u003e3\u003c/sub\u003eS\u003csup\u003e\u0026ndash;\u003c/sup\u003e(339.97025, 2.09 ppm) was observed with the fragments O\u003csub\u003e2\u003c/sub\u003eS\u003csup\u003e\u0026ndash;\u003c/sup\u003e (63.96249, 0.67 ppm) and HO\u003csub\u003e2\u003c/sub\u003eS\u003csup\u003e\u0026ndash;\u003c/sup\u003e(64.97031, 0.58 ppm), along with the retention time of 30.06 min, which was detected for the first time as perfluorobutane sulfonamido acetaldehyde (Figure S18).\u003c/p\u003e \u003cp\u003e \u003cb\u003eClass 8 Sulfonamido acealdehyde hydrate/hemiacetal\u003c/b\u003e C\u003csub\u003e6\u003c/sub\u003eH\u003csub\u003e5\u003c/sub\u003eF\u003csub\u003e9\u003c/sub\u003eNO\u003csub\u003e4\u003c/sub\u003eS\u003csup\u003e\u0026ndash;\u003c/sup\u003e(357.98, ppm) was observed with a neutral loss of H\u003csub\u003e2\u003c/sub\u003eO which was identified as perfluoroalkane sulfonamido acetaldehyde hydrate, as water adds to the carbonyl function of acetaldehydes (Figure S19). Moreover, C\u003csub\u003e7\u003c/sub\u003eH\u003csub\u003e7\u003c/sub\u003eF\u003csub\u003e9\u003c/sub\u003eNO\u003csub\u003e4\u003c/sub\u003eS\u003csup\u003e\u0026ndash;\u003c/sup\u003e (371.99, ppm) was detected with a neutral loss of CH\u003csub\u003e3\u003c/sub\u003eOH, which indicated the production of additional reaction of methanol to acetaldehyde. Hydrates and hemiacetals are the products of addition reactions of oxygen-based nucleophiles, such as water and methanol, to aldehydes, which have been reported for the first time.\u003c/p\u003e \u003cp\u003e \u003cb\u003eClass 9 carboxylic acid\u003c/b\u003e The classes comprising 6 subclasses, 9a-9f, all contained the -COOH functional group. Among these subclasses, three subclasses including perfluoroalkyl carboxylic acids (PFCAs), unsaturated PFCAs (U-PFCAs), and unsaturated perfluoroalkyl ether carboxylic acid (U-E-PFCAs) could be distinguished by the neutral loss of CO\u003csub\u003e2\u003c/sub\u003e. The MS2 spectrum of U-E-PFCA(C6) is shown in Figure S20. In addition, hydro-substituted PFCAs (H-PFCAs), hydro-substituted E-PFCAs (H-E-PFCAs) and H\u003csub\u003en\u003c/sub\u003e-E-PFCAs (subclasses 9a, 9b, 9c, 9d, and 9e) produced neutral loss of CO\u003csub\u003e2\u003c/sub\u003eHF, which was derived through the combination of CO\u003csub\u003e2\u003c/sub\u003e and HF, with HF originating from the hydrogen-substituted fluoroalkyl chain, as shown in Figure S21 and Figure S22 for H-PFCA(C4) and H\u003csub\u003e2\u003c/sub\u003e-E-PFCA(C4) respectively. Perfluoroalkyl ether carboxylic acid (E-PFCA) did not cuase the neutral loss of CO\u003csub\u003e2\u003c/sub\u003e. This lack of detection of [M-H]\u003csup\u003e\u0026ndash;\u003c/sup\u003e and [M-H-CO\u003csub\u003e2\u003c/sub\u003e]\u003csup\u003e\u0026ndash;\u003c/sup\u003e was probably due to in-source fragmentation of the precursor ion.[\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e, \u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e, \u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e] Therefore, the C\u003csub\u003en\u003c/sub\u003eF\u003csub\u003e2n+1\u003c/sub\u003eO\u003csup\u003e\u0026ndash;\u003c/sup\u003e fragments and the isotope pattern with fluoride were used for identification of this subclass.\u003c/p\u003e \u003cp\u003e \u003cb\u003eClass 10 dicarboxylic acid\u003c/b\u003e Perfluoroalkyl dioic acids (PFdiCA, C3-C8) are comprised of the functional group of dicarboxylic acid. PFdiCA (C3-C5) exhibited a neutral loss of CO\u003csub\u003e2\u003c/sub\u003e; PFdiCA (C6-C8) lacked the detection of neutral loss of CO\u003csub\u003e2\u003c/sub\u003e, presumably due to their low abundance in the samples. The fragment-based fluoroalkyl chain as C\u003csub\u003en\u003c/sub\u003eF\u003csub\u003e2n\u0026minus;1\u003c/sub\u003e and the isotopic pattern of fluorine could be alternatives to identify this subclass. Fragments of C\u003csub\u003e2\u003c/sub\u003eF\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e\u0026ndash;\u003c/sup\u003e, C\u003csub\u003e3\u003c/sub\u003eF\u003csub\u003e5\u003c/sub\u003e\u003csup\u003e\u0026ndash;\u003c/sup\u003e, C\u003csub\u003e4\u003c/sub\u003eF\u003csub\u003e7\u003c/sub\u003e\u003csup\u003e\u0026ndash;\u003c/sup\u003e, C\u003csub\u003e5\u003c/sub\u003eF\u003csub\u003e9\u003c/sub\u003e\u003csup\u003e\u0026ndash;\u003c/sup\u003e, and C\u003csub\u003e6\u003c/sub\u003eF\u003csub\u003e11\u003c/sub\u003e\u003csup\u003e\u0026ndash;\u003c/sup\u003e (C\u003csub\u003en\u003c/sub\u003eF\u003csub\u003e2n\u0026minus;1\u003c/sub\u003e\u003csup\u003e\u0026ndash;\u003c/sup\u003e) were detected in the spectrum of PFdiCA(C4 to C8) respectively. The fragment C\u003csub\u003e2\u003c/sub\u003eHF\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e2\u003c/sub\u003e\u003csup\u003e\u0026ndash;\u003c/sup\u003e, C\u003csub\u003e3\u003c/sub\u003eHF\u003csub\u003e4\u003c/sub\u003eO\u003csub\u003e2\u003c/sub\u003e\u003csup\u003e\u0026ndash;\u003c/sup\u003e, C\u003csub\u003e4\u003c/sub\u003eHF\u003csub\u003e6\u003c/sub\u003eO\u003csub\u003e2\u003c/sub\u003e\u003csup\u003e\u0026ndash;\u003c/sup\u003e were detected by the neutral loss of CO\u003csub\u003e2\u003c/sub\u003e from [M-H]\u003csup\u003e\u0026minus;\u003c/sup\u003e of PFdiCA(C3-C5).\u003c/p\u003e \u003cp\u003e \u003cb\u003eClass 11 sulfonic acid\u003c/b\u003e Perfluoroalkyl sulfonic acids (PFSAs, subclass 11a, C1 and C4) and hydrogen-substituted PFSA (H-PFSA, subclass 11b, C2-C4) were distinguished by the presence of SO\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e\u0026minus;\u003c/sup\u003e and SO\u003csub\u003e3\u003c/sub\u003eF\u003csup\u003e\u0026minus;\u003c/sup\u003e. In the case of multi-hydrogen-substituted perfluoroalkyl ether sulfonic acids (H\u003csub\u003e2\u003c/sub\u003e-E-PFSA, C4), the dominant fragments of polar head shifted from SO\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e\u0026minus;\u003c/sup\u003e to HSO\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e\u0026minus;\u003c/sup\u003e. Additionally, for the subclasses with hydrogen-substituted PFSAs, such as H-PFSA(C2, C3) and H\u003csub\u003e2\u003c/sub\u003e-E-PFSA (C4), a neutral loss of HF was observed (Figure S23).\u003c/p\u003e \u003cp\u003e \u003cb\u003eClass 12 Sulfinic acid\u003c/b\u003e Subclass 4 perfluorobutyl sulfinate (PFBSi) was identified with clear fragments of SO\u003csub\u003e2\u003c/sub\u003eF\u003csup\u003e\u0026minus;\u003c/sup\u003e as the specific feature of sulfinic acid. It was further confirmed with an authentic standard based on the retention time and the MS/MS spectrum. Perfluoroalkane sulfinic acids, arising from the degradation of commercial precursor compounds containing the C\u003csub\u003en\u003c/sub\u003eF\u003csub\u003e2n+1\u003c/sub\u003eSO\u003csub\u003e2\u003c/sub\u003eN moiety, may act as degradation by-products of fluorosurfactants in 3M foam.[\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e]\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003e3.2 Byproducts from chemical formulation\u003c/h2\u003e \u003cp\u003eTwo primary methods for PFAS production are the electrochemical fluorination (ECF) process, favored by 3M,[\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e, \u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e] and the telomerization process, employed by DuPont.[\u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e33\u003c/span\u003e] The ECF process generates byproducts, along with both shorter and longer PFAS, with a higher prevalence of branched PFAS, while the telomerization process primarily yields normal PFAS.[\u003cspan citationid=\"CR34\" class=\"CitationRef\"\u003e34\u003c/span\u003e] In our previous study on semiconductor wastewater,[\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e] FBSE was found at concentrations ranging from 0.883 to 482 \u0026micro;g/L. FBSE is associated with 3M's electronic surfactant 4200,[\u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e35\u003c/span\u003e] which is added to buffered hydrofluoric acid (BHF) for etching solutions in semiconductor manufacturing to enhance wetting properties and improving pattern quantity performance. In this study, we reported several FBSE derivatives with varying fluoroalkyl chain lengths in wastewater. The relative proportions to FBSE are as follows, in descending order: H-FBSE (0.06%), E-FBSE (0.03%), U-E-FBSE (0.005%), U-FBSE (0.004%), H-E-FBSE (0.001%), FPrSE (0.004%) and FEtSE (0.001%) contribute to a total of approximately 0.1%. The varied retention times (RTs) of these substances compared to that of FBSE (29.9 min) are as follows: E-FBSE (33.8\u0026ndash;34.9 min)\u0026thinsp;\u0026gt;\u0026thinsp;U-E-FBSE (23.3 min)\u0026thinsp;\u0026asymp;\u0026thinsp;H-E-FBSE (21.1min)\u0026thinsp;\u0026gt;\u0026thinsp;U-FBSE (16.9 min)\u0026thinsp;\u0026asymp;\u0026thinsp;H-FBSE (16.0 min) and FPrSE (18.4 min) and FEtSE (9.4 min). The use of a reversed-phase C18 column for analysis indicates that, in terms of polarity, only E-FBSE was less polar than FBSE, while the others were less polar, resulting in faster elution. This suggests that in wastewater treatment, using hydrophobic interaction separation methods such as activated carbon adsorption may lead to lower removal efficiency for these polar substances, decreasing susceptibility to adsorption removal. When discharged from wastewater treatment plants, the environmental distribution of these substances may differ significantly due to their distinct properties, which should also be considered.\u003c/p\u003e \u003cp\u003eThe aforementioned FBSE derivative series, including H-FBSE, U-E-FBSE, U-FBSE, E-FBSE, H-E-FBSE, FPrSE, and FEtSE, was confirmed to exist in accordance with the authentic standard of FBSE. However, due to uncertainties about any additional separation in the standard production process, we refrained from directly comparing the proportions of the FBSE derivative series in the standard to those in the samples. In addition, FBSA includes similar byproducts from production, such as H-FBSA and E-FBSA. Nevertheless, we infer that the aforementioned FBSE derivative series and FBSA derivatives may be byproducts produced during the formulation of chemicals used by semiconductor factories.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003e3.3 Reaction products\u003c/h2\u003e \u003cp\u003eDue to the intricate nature of semiconductor processes, among the 12 prominent semiconductor industries in South Korea, 11 utilize 135 chemical constituents.[\u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e36\u003c/span\u003e] These include sulfuric acid, chromic acid, tetramethyl ammonium hydroxide, ethylene oxide, potassium dichromate, isopropanol, and formaldehyde. Despite this extensive usage, 33% (range: 16\u0026ndash;56%) of the chemical compositions remain undisclosed due to commercial confidentiality. Notably, the undisclosed ingredients are predominantly employed in the photolithography process. The complex chemical condition involved in these semiconductor processes include strong acids, alkalis, and potent oxidants, and UV light is used in the photolithography process. Among the intricate blends of industrial chemicals in sewage, various reactions may take place, including hydration, oxidation, sulfonation, amide formation, and nitration. Additionally, during the biological treatment in wastewater treatment plants, reactions such as oxidation, deamination, desulfonation, and dicarboxylation occur. Due to the exceptional stability of the fluoroalkyl chain, reactions in the polar functional section led to distinct mass defect values for each transformation. This renders the use of homologous patterns for screening impractical. Our fragment-based approach overcomes the limitations of conventional homologous series. In total, we have identified 80 PFAS from 43 subclasses, with 29 substances reported for the first time. (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e)\u003c/p\u003e \u003cp\u003eOxidizing FBSEE diol yields FBSEE diacid, and FBSE oxidation produces tentatively identified FBSAA. Due to the lack of standards, the tentative identifications of FBSEE diacid and FBSAA remained at CL 2b. [\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e] A key distinction in current study is the inclusion of a standard for FBSAA confirmation. Through RT alignment and consistent MS2 spectra, we verified the presence of PFBSAA at 15.5 minutes with CL1. Notably, an isomer of FBSAA with higher polarity presented at RT 9.93 minutes, showcasing distinct MS2 spectra (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e1\u003c/span\u003e4c) that suggest structural differences. Considering the potential isomerization between acid and diol forms [\u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e37\u003c/span\u003e], fragment analysis led to the proposal of a diol structure for the isomers. However, based on the fragments observed in the MS2 spectrum, the potential existence of another structural isomer is suggested, which is simultaneously illustrated in Figure S16c. In addition, we introduce intermediate products of FBSE oxidation: FBSAcAL (RT 29.94 min) and its hydrated form as FBSAcAL hydrate, detected for the first time via mass spectrometry. Another structural isomer of FBSAcAL at RT 13.03 minutes was identified with higher polarity. Here, we propose an oxidation pathway, including the first publication of intermediate transformations of aldehyde, aldehyde hydrate, and FBSAA in Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e1\u003c/span\u003e.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eFBSA-PrNO\u003csub\u003e2\u003c/sub\u003e and FBSE-Am are isomers with distinct polar head groups\u0026mdash;sulfonamide and sulfonamido ethanol, respectively. (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e2\u003c/span\u003e) FBSA-PrNO\u003csub\u003e2\u003c/sub\u003e exhibit SO\u003csub\u003e2\u003c/sub\u003eN\u003csup\u003e\u0026minus;\u003c/sup\u003e fragment along with an additional signal for the neutral loss of C\u003csub\u003e3\u003c/sub\u003eH\u003csub\u003e5\u003c/sub\u003eNO\u003csub\u003e2\u003c/sub\u003e, categorizing it as miscellaneous FASAs (Subclass 1h). In contrast, FBSE-Am demonstrates a specific signal at 121.99174, confirming its classification as FASEs, and its neutral loss of CONH categorizes it within the miscellaneous FASEs (Subclass 2h). The retention time of FBSA-PrNO\u003csub\u003e2\u003c/sub\u003e was 8.81 minutes, while that of FBSE-Am was 29.97 minutes, indicating significant differences in polarity. Thus, the headgroup isomers exhibit unique reactivity and physicochemical properties, may impact the variations in sludge metabolism during wastewater treatment in WWTPs[\u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e38\u003c/span\u003e]. Furthermore, E-FBSEs and FBSEAcAL hydrate (Subclass 8a) are differentiated by their respective polar head groups: sulfonamido ethanol and sulfonamido acetaldehyde hydrate. (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e3\u003c/span\u003e) Specifically, fragment 121.99174 is unique to sulfonamido ethanol, while the hydrate can be identified by the neutral loss of H\u003csub\u003e2\u003c/sub\u003eO. Finally, MeFBSAA and FBSPrA, which are polar head isomers, exhibit differences in the number of carbons in the sulfonamido carboxylic acid. (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e4\u003c/span\u003e) This clearly results in distinct neutral losses\u0026mdash;one for acetic acid (CH\u003csub\u003e2\u003c/sub\u003eCO\u003csub\u003e2\u003c/sub\u003e) and the other for propanoic acid (C\u003csub\u003e2\u003c/sub\u003eH\u003csub\u003e4\u003c/sub\u003eCO\u003csub\u003e2\u003c/sub\u003e). Additionally, MeFASAA showed no NSO\u003csub\u003e2\u003c/sub\u003e\u003csup\u003e\u0026minus;\u003c/sup\u003e fragment signal, indicating solely the presence of only the SO\u003csub\u003e2\u003c/sub\u003eF\u003csup\u003e\u0026minus;\u003c/sup\u003e fragment signal due to N-methyl substitution. Conversely, FBSPrA exhibited a distinct NSO\u003csub\u003e2\u003c/sub\u003e\u003csup\u003e\u0026minus;\u003c/sup\u003e fragment, signifying the lack of N-alkylation. The specific fragmentation patterns have been classified under class 4 in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e. This investigation unveiled 22 isomeric PFAS, including isomers with different headgroups and functional tail groups. These results emphasize the significance of understanding varied reactions and the overall composition of PFAS emissions in semiconductor wastewater, highlighting its complexity and posing challenges for subsequent wastewater treatment.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e"},{"header":"Conclusion","content":"\u003cp\u003eFor the nontarget PFAS approach, mass defect and homologous patterns are potent tools for uncovering PFAS within a series of homologous substances. However, industrial chemicals exhibit diverse and unique functional groups, making homologues less likely to occur in industrial manufacturing. Moreover, the intricate blend of industrial chemicals in sewage may undergo diverse reactions, such as hydrolysis, oxidation and deamination. As these reactions unfold in the polar functional section, each transformation leads to distinct mass defect values, rendering the use of homologous patterns for screening. Consequently, our research employs a fragment-based approach to investigate nontarget PFAS, particularly focusing on hydrophilic head groups, overcoming the limitations of conventional homologous series. Utilizing this approach, we successfully identified 80 PFAS in sewage and effluent samples from semiconductor plants, including 29 newly discovered compounds, which are categorized into three groups (1) The byproducts of primary PFAS formulations, such as perfluorobutane sulfonamide and perfluorobutane sulfonamido (di)ethanols, include components that constitute less than 0.1% of the total area compared to the main components. These byproducts, which exhibit variations in fluoroalkyl chains such as hydrogen-substituted, unsaturated, and ether structures, were identified for the first time in authentic standards, suggesting that they originated as byproducts from the chemical manufacturing process. (2) Compounds that undergo intermediate transformation compounds during the oxidation of perfluorobutane sulfonamido ethanol, specifically perfluorobutane sulfonamido acetaldehyde and its hydrate, are newly identified. (3) Diverse reaction products generated from the intricate processes of semiconductor manufacturing, which utilize strong acids, bases, and solvents under UV light or heat conditions, include novel PFAS-related reaction compounds generated through hydrolysis, sulfonation and nitrification.\u003c/p\u003e \u003cp\u003eIn brief, these discoveries underscore the efficacy of the fragment-based approach in identifying unique industrial chemicals and its value in understanding diverse reactions and the actual emission compositions of PFAS in semiconductor wastewater. Moreover, under the Stockholm Convention's regulation for PFAS precursor elimination, complexity arises due to the absence of standards and standardized identification methods for diverse PFAS precursors, which undergo degradation to form terminal PFAS through the amendment of polar functional groups. This poses challenges in recognizing and quantifying the levels of products, complicating market surveillance. Our streamlined fragment-based approach addresses these hurdles and provides a strategic concept for identifying PFAS precursors, particularly those exhibiting versatility in polar functional groups.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAcknowledgments\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWe extend our gratitude to Tzu-Hui Wang for her support in the pretreatment procedures and Meng-Chi Huang for his assistance in verifying the chemical structures.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors\u0026rsquo; contributions\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eYi-Ju Chen: study design, experimental work, data analysis, writing and editing manuscript. Jheng-Sian Yang: experimental work and editing manuscript. Angela Yu-Chen Lin: supervision and funding acquisition. The authors read and approved the final manuscript.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eFinancial support for this study was provided by the Taiwan National Science and Technology Council through the following projects: MOST 111\u0026ndash;2221-E-002\u0026ndash;047-MY3 and MOST 111\u0026ndash;2221-E-002\u0026ndash;042-MY3.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and materials\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll data generated or analyzed during this study are included within the article.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare that they have no competing interest.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor details\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003csup\u003e1\u0026nbsp;\u003c/sup\u003eNational Environmental Research Academy, Ministry of Environment, Taoyuan City, 320, Taiwan. \u003csup\u003e2\u003c/sup\u003eGraduate Institute of Environmental Engineering, National Taiwan University, Taipei City, 106, Taiwan\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eGl\u0026uuml;ge J, Scheringer M, Cousins IT, DeWitt JC, Goldenman G, Herzke D, et al. 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PFAS-Containing Wet Chemistries Used in Semiconductor Manufacturing, Semiconductor PFAS Consortium Wet Chemicals Working Group. 2023.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eYoon C, Kim S, Park D, Choi Y, Jo J, Lee K. Chemical Use and Associated Health Concerns in the Semiconductor Manufacturing Industry. Safety and Health at Work 2020;11(4):500\u0026ndash;8.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eRogers CO, Lockwood KS, Nguyen QL, Labbe NJ. Diol isomer revealed as a source of methyl ketene from propionic acid unimolecular decomposition. International Journal of Chemical Kinetics 2021;53(12):1272\u0026ndash;84.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLondhe K, Lee C-S, McDonough CA, Venkatesan AK. The Need for Testing Isomer Profiles of Perfluoroalkyl Substances to Evaluate Treatment Processes. Environmental Science \u0026amp; Technology 2022;56(22):15207\u0026ndash;19.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":true,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"sustainable-environment-research","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"sere","sideBox":"Learn more about [Sustainable Environment Research](https://sustainenvironres.biomedcentral.com)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/sere/default.aspx","title":"Sustainable Environment Research","twitterHandle":"@BioMedCentral","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Per- and polyfluoroalkyl substances, PFAS, Semiconductor, Perfluorobutane sulfonamido ethanol, Perfluorobutane sulfonamide, Transformation products, Byproducts, Aldehyde hydration","lastPublishedDoi":"10.21203/rs.3.rs-3928681/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-3928681/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eSemiconductor manufacturing employs per- and polyfluoroalkyl substances (PFAS) as fluoroasurfactants to enhance the quality of photolithography lines. Our research, employing a fragment-based approach to investigate nontarget PFAS, overcomes conventional homologous series limitations. We identified 80 PFAS in wastewater and effluent samples from semiconductor industry, including 29 newly discovered compounds, categorized into three groups. First, primary PFAS formulations, such as perfluorobutane sulfonamide and perfluorobutane sulfonamido (di)ethanols, are accompanied by byproducts comprising approximately 0.1% of the total height compared to the main components. These byproducts, which exhibit variations in fluoroalkyl chains such as hydro-substituted, unsaturated, or ether structures, were reported for the first time to exist in commercially authentic standards, indicating their possible origin as byproducts of chemical manufacturing process. Second, transformation products from perfluorobutane sulfonamido ethanol during oxidation, including the first identified intermediate transformation compounds, perfluorobutane sulfonamido acetaldehyde and its hydrate, were obtained. Third, diverse reaction products are generated from the intricate processes of semiconductor manufacturing, which utilize strong acids, bases, and solvents under UV light or heated conditions. These processes include the formation of PFAS-related compounds through hydration, sulfonation, oxidation, and nitrification. This study revealed 22 isomeric PFAS, encompassing headgroup isomers and functional tail group isomers. These findings underscore the importance of comprehending diverse reactions and the overall emission compositions of PFAS in semiconductor wastewater, highlighting its complexity and presenting challenges for subsequent wastewater treatment.\u003c/p\u003e","manuscriptTitle":"Comprehensive Nontargeted Analysis of Fluorosurfactant Byproducts and Reaction Products in Wastewater from Semiconductor Manufacturing","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-02-27 08:21:06","doi":"10.21203/rs.3.rs-3928681/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Major revision","date":"2024-03-14T21:32:12+00:00","index":"","fulltext":""},{"type":"reviewerAgreed","content":"","date":"2024-02-22T23:55:48+00:00","index":0,"fulltext":""},{"type":"reviewersInvited","content":"","date":"2024-02-22T23:52:02+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2024-02-07T09:31:10+00:00","index":"","fulltext":""},{"type":"submitted","content":"Sustainable Environment Research","date":"2024-02-06T04:36:33+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"sustainable-environment-research","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"sere","sideBox":"Learn more about [Sustainable Environment Research](https://sustainenvironres.biomedcentral.com)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/sere/default.aspx","title":"Sustainable Environment Research","twitterHandle":"@BioMedCentral","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"5bf4c032-2e30-45b7-967c-8c627bfd77da","owner":[],"postedDate":"February 27th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2024-08-01T16:17:39+00:00","versionOfRecord":{"articleIdentity":"rs-3928681","link":"https://doi.org/10.1186/s42834-024-00221-1","journal":{"identity":"sustainable-environment-research","isVorOnly":false,"title":"Sustainable Environment Research"},"publishedOn":"2024-07-15 16:05:13","publishedOnDateReadable":"July 15th, 2024"},"versionCreatedAt":"2024-02-27 08:21:06","video":"","vorDoi":"10.1186/s42834-024-00221-1","vorDoiUrl":"https://doi.org/10.1186/s42834-024-00221-1","workflowStages":[]},"version":"v1","identity":"rs-3928681","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-3928681","identity":"rs-3928681","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}