Health & Environmental Research Online (HERO)


FtS 6:2 (27619-97-2)


59 References Were Found:

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Characterization of occurrence, sources and sinks of perfluoroalkyl and polyfluoroalkyl substances (PFASs) in a tropical urban catchment

Authors: Chen, H; Reinhard, M; Nguyen, TV; You, L; He, Y; Gin, KY (2017) Environmental Pollution 227:397-405. HERO ID: 3856452

[Less] Understanding the sources, occurrence and sinks of perfluoroalkyl and polyfluoroalkyl substances (PFASs) . . . [More] Understanding the sources, occurrence and sinks of perfluoroalkyl and polyfluoroalkyl substances (PFASs) in the urban water cycle is important to protect and utilize local water resources. Concentrations of 22 target PFASs and general water quality parameters were determined monthly for a year in filtered water samples from five tributaries and three sampling stations of an urban water body. Of the 22 target PFASs, 17 PFASs were detected with a frequency >93% including PFCAs: C4-C12 perfluoroalkyl carboxylates, C4, C6, C8, and C10 perfluoroalkane sulfonates, perfluorooctane sulfonamides and perfluorooctane sulfonamide substances (FOSAMs), C10 perfluoroalkyl phosphonic acid (C10 PFPA), 6:2 fluorotelomer sulfonic acid (6:2 FTSA) and C8/C8 perfluoroalkyl phosphinic acid (C8/C8-PFPIA). The most abundant PFASs in water were PFBS (1.4-55 ng/L), PFBA (1.0-23 ng/L), PFOS (1.5-24 ng/L) and PFOA (2.0-21 ng/L). In the tributaries, PFNA concentrations ranged from 1.2 to 87.1 ng/L except in the May 2013 samples of two tributaries, which reached 520 and 260 ng/L. Total PFAS concentrations in the sediment samples ranged from 1.6 to 15 ng/g d.w. with EtFOSAA, PFDoA, PFOS and PFDA being the dominant species. Based on water and sediment data, two types of sources were inferred: one-time or intermittent point sources and continuous non-point sources. FOSAMs and PFOS released continually from non-point sources, C8/C8 PFPIA, PFDoA and PFUnA was released from point sources. The highly water soluble short-chain PFASs including PFBA, PFPeA and PFBS remained predominantly in the water column. The factors governing solution phase concentrations appear to be compound hydrophobicity and sorption to suspended particles. Correlation of the dissolved phase concentrations with precipitation data suggested stormwater was a significant source of PFBA, PFBS, PFUnA and PFDoA. Negative correlations with precipitation indicated sources feeding FOSAA and FOSA directly into the tributaries.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Heat-activated persulfate oxidation of PFOA, 6:2 fluorotelomer sulfonate, and PFOS under conditions suitable for in-situ groundwater remediation

Authors: Park, S; Lee, LS; Medina, VF; Zull, A; Waisner, S (2016) Chemosphere 145:376-383. HERO ID: 3076786

[Less] PFOA (perfluorooctanoic acid) oxidation (0.121-6.04 μM) by heat-activated persulfate was evaluated at . . . [More] PFOA (perfluorooctanoic acid) oxidation (0.121-6.04 μM) by heat-activated persulfate was evaluated at 20-60 °C with 4.2-84 mM [Formula: see text] and in the presence of soluble fuel components to assess feasibility for in-situ remediation of groundwater. 6:2 fluorotelomer sulfonic acid/sulfonate (6:2 FTSA) and PFOS (perfluorooctanesulfonic acid) persulfate oxidation was also evaluated in a subset of conditions given their co-occurrence at many sites. High performance liquid chromatography electron spray tandem mass spectrometry was used for organic analysis and fluoride was measured using a fluoride-specific electrode. PFOA pseudo-1st order transformation rates (k1,PFOA) increased with increasing temperature (half-lives from 0.1 to 7 d for 60 to 30 °C) sequentially removing CF2 groups ('unzipping') to shorter chain perfluoroalkyl carboxylic acids (PFCAs) and F(-). At 50 °C, a 5-fold increase in [Formula: see text] led to a 5-fold increase in k1,PFOA after which self-scavenging by sulfate radicals decreased the relative rate of increase with more [Formula: see text] . Benzene, toluene, ethylbenzene and xylene did not affect k1,PFOA even at 40 times higher molar concentrations than PFOA. A modeling approach to explore pathways strongly supported that for 6:2 FTSA, both the ethyl linkage and CF2-CH2 bond of 6:2 FTSA oxidize simultaneously, resulting in a ratio of ∼25/75 PFHpA/PFHxA. The effectiveness of heat-activated [Formula: see text] on PFOA oxidation was reduced in a soil slurry; therefore, repeated persulfate injections are required to efficiently achieve complete oxidation in the field. However, PFOS remained unaltered even at higher activation temperatures, thus limiting the sole use of heat-activated persulfate for perfluoroalkyl substances removal in the field.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

An alternative treatment method for fluorosurfactant-containing wastewater by aerosol-mediated separation

Authors: Ebersbach, I; Ludwig, SM; Constapel, M; Kling, HW (2016) Water Research 101:333-340. HERO ID: 3358193

[Less] The treatment of fluorosurfactant-containing wastewater is still challenging nowadays. Here, a method . . . [More] The treatment of fluorosurfactant-containing wastewater is still challenging nowadays. Here, a method is presented to remove fluorosurfactants from water, amongst others from electroplating wastewater. This elimination technique is based on the generation of gas bubbles in solution, enrichment and scavenging of fluorosurfactants by transport of the gas bubbles to the water surface. Finally the bubbles collapse and release an aerosol which is enriched with fluorosurfactants. By sampling of the released aerosols a mass balance was established for 6:2 fluorotelomer sulfonic acid (6:2 FTSA). Thereby 99.8% of the initial amount was revocered in the collected aerosols. Fluorosurfactant concentration in solution decreased exponentially with half-lives ranging from 2 to 6 min for 6:2 FTSA as well as perfluorooctane carboxylate (PFOA) and perfluorooctane sulfonate (PFOS). Elimination rate in defined matrix (0.2 M H2SO4) within 60 min was 99.6, 99.9 and 99.8% for 6:2 FTSA, PFOA and PFOS, respectively. The removal rate of 6:2 FTSA increased in solutions with higher ionic strength. Different wastewater from an electroplating industry containing 6:2 FTSA was treated with the described method without any sample pre-treatment and elimination of 6:2 FTSA took place with the same effectiveness as in synthetic matrices.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Microbial toxicity and biodegradability of perfluorooctane sulfonate (PFOS) and shorter chain perfluoroalkyl and polyfluoroalkyl substances (PFASs)

Authors: Ochoa-Herrera, V; Field, JA; Luna-Velasco, A; Sierra-Alvarez, R (2016) Environmental Science: Processes & Impacts 18:1236-1246. HERO ID: 3856467

[Less] Perfluorooctane sulfonate (PFOS) and related perfluoroalkyl and polyfluoroalkyl substances (PFASs) are . . . [More] Perfluorooctane sulfonate (PFOS) and related perfluoroalkyl and polyfluoroalkyl substances (PFASs) are emerging contaminants that have been widely applied in consumer and industrial applications for decades. However, PFOS has raised public concern due to its high bioaccumulative character, environmental persistence, and toxicity. Shorter PFASs such as perfluorobutane sulfonate (PFBS) and polyfluoroalkyl compounds have been proposed as alternatives to PFOS but it is unclear whether these fluorinated substances pose a risk for public health and the environment. The objective of this research was to investigate the microbial toxicity and the susceptibility to microbial degradation of PFOS and several related fluorinated compounds, i.e., short-chain perfluoroalkyl and polyfluoroalkyl sulfonic and carboxylic acids. None of the compounds tested were toxic to the methanogenic activity of anaerobic wastewater sludge even at very high concentrations (up to 500 mg L(-1)). All PFASs evaluated were highly resistant to microbial degradation. PFOS was not reductively dehalogenated by the anaerobic microbial consortium even after very long periods of incubation (3.4 years). Similarly, the tested short chain perfluoroalkyl substances (i.e., PFBS and trifluoroacetic acid) and a polyfluoroalkyl PFOS analogue, 6 : 2 fluorotelomer sulfonic acid (FTSA) were also resistant to anaerobic biodegradation. Likewise, no conclusive evidence of microbial degradation was observed under aerobic conditions for any of the short-chain perfluoroalkyl and polyfluoroalkyl carboxylic acids tested after 32 weeks of incubation. Collectively, these results indicate that PFOS and its alternatives such as short chain perfluoroalkyl sulfonates and carboxylates and their polyfluorinated homologues are highly resistant to microbial degradation.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Biotransformation potential of 6:2 fluorotelomer sulfonate (6:2 FTSA) in aerobic and anaerobic sediment

Authors: Zhang, S; Lu, X; Wang, N; Buck, RC (2016) Chemosphere 154:224-230. HERO ID: 3857383

[Less] Aqueous film-forming foam (AFFF) products are used in industrial and military firefighting around the . . . [More] Aqueous film-forming foam (AFFF) products are used in industrial and military firefighting around the globe. These products contain fluoroalkylthioamido sulfonates, fluoroalkylthiobetaine, and other related substances as the major ingredients, which can be biotransformed in the environment to form 6:2 fluorotelomer sulfonate (6:2 FTSA, F(CF2)6CH2CH2SO3-) as one of the major initial biotransformation products. Limited information is available on 6:2 FTSA aerobic biotransformation in activated sludge and pure microbial culture. This is the first study to report 6:2 FTSA biotransformation in aerobic and anaerobic sediment. 6:2 FTSA was rapidly biotransformed in aerobic river sediment with a half-life less than 5 d. Major stable transformation products observed after 90 d included 5:3 Acid [F(CF2)5CH2CH2COOH), 16 mol%), PFPeA [F(CF2)4COOH, 21 mol%] and PFHxA (F(CF2)5COOH, 20 mol%). 6:2 fluorotelomer alcohol [6:2 FTOH, F(CF2)6CH2CH2OH] was readily biotransfomed whereas 6:2 FTSA biotransformation did not occur in anaerobic sediment over 100 d, indicating that the enzymatic desulfonation step limited 6:2 FTSA biotransformation in anaerobic sediment. These results suggest that 6:2 FTSA related products, after release to the aerobic environment, is likely to biodegrade forming 5:3 Acid, PFPeA and PFHxA. This study also indicates that 6:2 FTSA formed from its aforementioned precursors may be persistent in the anaerobic environment after their potential release. This work provides insight to understanding the fate and environmental loading of AFFF-related products and their major transformation products in the environment.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Poly- and perfluoroalkyl substances in wastewater: Significance of unknown precursors, manufacturing shifts, and likely AFFF impacts

Authors: Houtz, EF; Sutton, R; Park, JS; Sedlak, M (2016) Water Research 95:142-149. HERO ID: 3858259

[Less] In late 2014, wastewater effluent samples were collected from eight treatment plants that discharge . . . [More] In late 2014, wastewater effluent samples were collected from eight treatment plants that discharge to San Francisco (SF) Bay in order to assess poly- and perfluoroalkyl substances (PFASs) currently released from municipal and industrial sources. In addition to direct measurement of twenty specific PFAS analytes, the total concentration of perfluoroalkyl acid (PFAA) precursors was also indirectly measured by adapting a previously developed oxidation assay. Effluent from six municipal treatment plants contained similar amounts of total PFASs, with highest median concentrations of PFHxA (24 ng/L), followed by PFOA (23 ng/L), PFBA (19 ng/L), and PFOS (15 ng/L). Compared to SF Bay municipal wastewater samples collected in 2009, the short chain perfluorinated carboxylates PFBA and PFHxA rose significantly in concentration. Effluent samples from two treatment plants contained much higher levels of PFASs: over two samplings, wastewater from one municipal plant contained an average of 420 ng/L PFOS and wastewater from an airport industrial treatment plant contained 560 ng/L PFOS, 390 ng/L 6:2 FtS, 570 ng/L PFPeA, and 500 ng/L PFHxA. The elevated levels observed in effluent samples from these two plants are likely related to aqueous film forming foam (AFFF) sources impacting their influent; PFASs attributable to both current use and discontinued AFFF formulations were observed. Indirectly measured PFAA precursor compounds accounted for 33%-63% of the total molar concentration of PFASs across all effluent samples and the PFAA precursors indicated by the oxidation assay were predominately short-chained. PFAS levels in SF Bay effluent samples reflect the manufacturing shifts towards shorter chained PFASs while also demonstrating significant impacts from localized usage of AFFF.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Comparison of PFASs contamination in the freshwater and terrestrial environments by analysis of eggs from osprey (Pandion haliaetus), tawny owl (Strix aluco), and common kestrel (Falco tinnunculus)

Authors: Eriksson, U; Roos, A; Lind, Y; Hope, K; Ekblad, A; Kärrman, A (2016) Environmental Research 149:40-47. HERO ID: 3860067

[Less] The level of PFAS (per- and polyfluorinated alkyl substances) contamination in freshwater and terrestrial . . . [More] The level of PFAS (per- and polyfluorinated alkyl substances) contamination in freshwater and terrestrial Swedish environments in 2013/2014 was assessed by analyzing a range of perfluorinated alkyl acids, fluorotelomer acids, sulfonamides, sulfonamidoethanols and polyfluoralkyl phosphate diesters (diPAPs) in predator bird eggs. Stable isotopes ((13)C and (15)N) were analyzed to elucidate the dietary source. The tawny owl (Strix aluco, n=10) and common kestrel (Falco tinnunculus, n=40), two terrestrial species, and the osprey (Pandion haliaetus, n=30), a freshwater specie were included. In addition, a temporal trend (1997-2001, 2008-2009, 2013) in osprey was studied as well. The PFAS profile was dominated by perfluorooctane sulfonic acid (PFOS) in eggs from osprey and tawny owl, while for common kestrel perfluorinated carboxylic acids (∑PFCA) exceeded the level of PFOS. PFOS concentration in osprey eggs remained at the same level between 1997 and 2001 and 2013. For the long-chained PFCAs, there were a significant increase in concentrations in osprey eggs between 1997 and 2001 and 2008-2009. The levels of PFOS and PFCAs were about 10 and five times higher, respectively, in osprey compared to tawny owl and common kestrel. Evidence of direct exposure from PFCA precursor compounds to birds in both freshwater and terrestrial environment was observed. Low levels of diPAPs were detected in a few samples of osprey (<0.02-2.4ng/g) and common kestrel (<0.02-0.16ng/g) eggs, and 6:2 FTSA was detected in a majority of the osprey eggs (<6.3-52ng/g). One saturated telomer acid (7:3 FTCA), which is a transformation marker from precursor exposure, was detected in all species (<0.24-2.7ng/g). The (15)N data showed higher levels in osprey eggs compared to tawny owl and common kestrel, indicating that they feed on a 2-3 times higher trophic level. We conclude that ospreys are continuously exposed to PFAS at levels where adverse toxic effects have been observed in birds.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Surface-enhanced Raman scattering (SERS) detection of fluorosurfactants in firefighting foams

Authors: Fang, C; Megharaj, M; Naidu, R (2016) RSC Advances 6:11140-11145. HERO ID: 3859931

[Less] We demonstrated SERS (surface-enhanced Raman scattering) detection of fluorosurfactants (FSs), which . . . [More] We demonstrated SERS (surface-enhanced Raman scattering) detection of fluorosurfactants (FSs), which are commonly formulated in aqueous firefighting foams (AFFFs), by increasing their loading affinity and boosting their Raman activity. In order to increase FS's loading affinity, we introduced a cationic dye (ethyl violet or methyl blue) into the aqueous incubation solution to co-precipitate the FS onto the SERS substrate surface by forming an immiscible ion-pair (dye-FS). In the meantime, the Raman signal intensity was boosted due to the much higher Raman activity of the dye than that of FS. We compared two kinds of SERS substrate, patterned silver (Ag) surface and graphene oxide (GO) membrane, and noted the former (dye-FS-Ag) enhanced the Raman signal whilst the latter (dye-FS-GO) increased the loading affinity of the ion-pair due to the hydrophobic surface. We thus introduced silver nanoparticles (AgNPs) into the incubation solution (as well as dye) to co-precipitate FS onto the GO surface via an assembly of dye-FS-AgNP-GO. Using this assembly, we successfully detected FSs including pentadecafluorooctanoic acid (PFOA), perfluorooctanesulfonic acid (PFOS), and 1H,1H,2H,2H-perfluorooctanesulfonic acid (6: 2FTS), with a limit-of-detection (LOD) of similar to 50 ppb (similar to 120 nM) for PFOA.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Analysis of 29 per- and polyfluorinated compounds in water, sediment, soil and sludge by liquid chromatography-tandem mass spectrometry

Authors: Boiteux, V; Bach, C; Sagres, V; Hemard, J; Colin, A; Rosin, C; Munoz, JF; Dauchy, X (2016) HERO ID: 3860081

[Less] Several analytical methods were optimised for he analysis of 29 per- and polyfluoroalkyl substances . . . [More] Several analytical methods were optimised for he analysis of 29 per- and polyfluoroalkyl substances (PFASs), including perfluorocarboxylic acids, perfluoroalkyl sulphonic acids and t1uorotelomers (FTs), such as sulphonate, saturated carboxylic acid, unsaturated carboxylic acid, sulphonamide and sulphonamide betaine (FTAB), in environmental samples in order to assess pollution by PFASs around heavily contaminated sites. Non-filtered water samples were extracted, purified and pre-concentrated by a solid-phase extraction (SPE) procedure. Solid samples (sediments, soils and sludges) were extracted through solvent extraction under acidic conditions and thereafter purified and pre-concentrated using the same SPE procedure as for the water samples. An ultra-high performance liquid chromatography coupled to tandem mass spectrometry in negative electrospray ionisation mode was employed to separate and detect targeted compounds. Twelve labelled internal standards were used to provide an adequate correction compensating for matrix effects. The limits of quantification (LOQs) were between 4 and 10 ngit in water depending on the analytes. For solid samples, the LOQs were 2 ngig dry weight (dw) in sediments and soils, and 20 ngig dw in sludges for all analytes. A surrogate parameter method based on the carlaoxylaion of perfluoroalkyl acid precursors under basic pH conditions as furthermore implemented to estimate the occurrence of non targeted PFAS compounds. In order to evaluate the reliability of these analytical methods, environmental samples collected around a training area in France, where aqueous fire-fighting foam is used, were analysed. Of all the compounds detected in these environmental samples, 6:2 FTAB was found in the highest concentrations.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Human placental transfer of perfluoroalkyl acid precursors: Levels and profiles in paired maternal and cord serum

Authors: Yang, L; Wang, Z; Shi, Y; Li, J; Wang, Y; Zhao, Y; Wu, Y; Cai, Z (2016) Chemosphere 144:1631-1638. HERO ID: 3857461

[Less] Perfluoroalkyl acids (PFAAs) precursors, the indirect source of PFAA exposure, have been observed in . . . [More] Perfluoroalkyl acids (PFAAs) precursors, the indirect source of PFAA exposure, have been observed in environmental and human samples. However, the maternal-fetal transfer of these chemicals has not been well examined. In this study, 50 paired maternal and cord serum samples collected in Jiangsu province of China were analyzed for fifteen PFAA precursors. Among the detected PFAAs, 6:2 fluorotelomer sulfonate (6:2 FTS), N-methyl- and N-ethyl-perfluorooctanesulfonamidoacetates had comparable detection rate in both maternal and cord sera, while the mean concentrations and detection rates of 8:2 FTS and perfluorooctane sulfonamide (PFOSA) were higher in maternal sera compared to cord sera (Mann-Whitney U test, P < 0.05). Analysis of variance and least significant difference tests showed that the youngest maternal age group (21-24 years old) had the highest concentration of 6:2 FTS in cord sera. Maternal serum PFOSA was found significantly correlated with the cord serum perfluorooctanesulfonate (PFOS) (Spearman test, r = 0.361, P = 0.010), indicating that maternal serum PFOSA might be an indirect source of PFOS in fetuses. The obtained results suggested the potential prenatal exposure and human placental transfer of perfluoroalkyl acid precursors.