Health & Environmental Research Online (HERO)


PFHxA (307-24-4)


477 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

Removal of eight perfluoroalkyl acids from aqueous solutions by aeration and duckweed

Authors: Zhang, W; Liang, Y (2020) Science of the Total Environment 724:138357. HERO ID: 6356904

[Less] Poly- and perfluoroalkyl substances (PFAS) are surfactants. Leveraging their surface active feature, . . . [More] Poly- and perfluoroalkyl substances (PFAS) are surfactants. Leveraging their surface active feature, this work investigated using aeration to remove perfluoroalkyl acids (PFAAs) from aqueous solutions. Eight PFAAs were spiked to either deionized water or Hoagland solution at three pHs. After 7 h of aeration, removals of perfluorobutanoic acid (PFBA), perfluoropentanoic acid (PFPeA), perfluorobutanesulfonic acid (PFBS), and perfluorohexanoic acid (PFHxA) were marginal and much lower than those of and perfluoroheptanoic acid (PFHpA), perfluorohexanesulfonic acid (PFHxS), perfluorooctanoic acid (PFOA), perfluorooctanesulfonic acid (PFOS). In deionized water, close to 80% of PFOA and PFOS at 200 ppb were removed when the pH was 2.3. The Hoagland solution at pH 2.3 and 5.0 benefited removal of long-chain PFAS at 2 ppb, but not at 200 ppb. With duckweed growing on the Hoagland solution surface, >95% of PFHpA, PFHxS, PFOA, and PFOS at 200 ppb were removed after 2 weeks. Aeration enhanced duckweed uptake of PFHxS, PFOA, and PFOS at 2 ppb significantly. Specific to PFOS, duckweed accumulated 14.4% of this compound initially spiked at 2 ppb in 2 weeks. These results demonstrated that aeration plus duckweed could be a viable and scalable remediation solution for surface water contaminated by PFAS.

Journal Article
Journal Article

Hyphenated High Performance Liquid Chromatography-Tandem Mass Spectrometry Techniques for the Determination of Perfluorinated Alkylated Substances in Lombardia Region in Italy, Profile Levels and Assessment: One Year of Monitoring Activities During 2018

Authors: Barreca, S; Busetto, M; Colzani, L; Clerici, L; Marchesi, V; Tremolada, L; Daverio, D; Dellavedova, P (2020) HERO ID: 6392504

[Less] In this research paper, we report a hyphenated technique based on ultra-high performance liquid chromatography-tandem . . . [More] In this research paper, we report a hyphenated technique based on ultra-high performance liquid chromatography-tandem mass spectrometry for the determination of twelve Perfluorinated Alkylated Substances in surface and groundwater samples from Lombardia Region during the monitoring activities in 2018 as new emerging and toxic pollutants. A green analytic method, developed by using an online Solid Phase Extraction coupled with UHPLC-MS/MS and previously validated, was applied for 4992 determinations conducted on 416 samples from 109 different sampling stations. Among the results, PFOS, PFOA, PFBA, PFBS, PFPeA and PFHxA were identified as the most abundant analytes detected. PFASs concentrations, in most cases, were below the limits of quantification and, in the cases where the limits of quantification have been exceeded, the values found were lower than Italy directive. PFOS is an exception and in fact this compound was detected in 76% of analyzed samples (surface and ground waters). Solid phase extraction with high performance liquid chromatography-tandem Mass Spectrometry has proved to be a very good Hyphenated techniques able to detect low concentrations of pollutants in surface and groundwater samples.

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

Evaluation of residues in hen eggs after exposure of laying hens to water containing per- and poly-fluoroalkyl substances

Authors: Wilson, TB; Stevenson, G; Crough, R; de Araujo, J; Fernando, N; Anwar, A; Scott, T; Quinteros, JA; Scott, PC; Archer, MJG (2020) HERO ID: 6356902

[Less] Per- and poly-fluoroalkyl substances (PFAS) have been used in aqueous film-forming foams (AFFF) used . . . [More] Per- and poly-fluoroalkyl substances (PFAS) have been used in aqueous film-forming foams (AFFF) used in firefighting, resulting in soil and groundwater contamination and leading to human exposure via animal products grown in contaminated areas. This study reports the relationship between PFAS intake by hens and the PFAS concentrations in the edible parts of eggs. Laying hens were exposed via drinking water to different concentrations of four PFAS compounds (Perfluorooctane sulfonate (PFOS), Perfluorohexane sulfonate (PFHxS), Perfluorooctanoic acid (PFOA) and Perfluorohexanoic acid (PFHxA)) over 61 days. Egg PFAS residues were assessed for a further 30 days after exposure ceased. The target concentrations of PFAS were 0, 0.3, 3, 30 and 300 µg/L for the treatment groups T1-T5, respectively, and PFAS residues were determined from the eggs collected every second day. There was a linear correlation between the PFAS concentrations in the drinking water of hens and those detected in the egg, which could be useful in estimating PFAS concentrations in the egg by measuring water concentrations. Exposure of hens to drinking water with PFAS concentrations below the Australian Government Department of Health limits (PFOS/PFHxS, 0.07 µg/L; PFOA, 0.56 µg/L), and with no other sources of PFAS exposure, is unlikely to result in egg PFAS concentrations that would exceed the 10% limit set by Food Standards Australia New Zealand (FSANZ) for human consumption. This article is protected by copyright. All rights reserved.

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

Removal efficiency and adsorption kinetics of perfluorohexanoic acid by MgAl-carbonate layered double hydroxide and its calcined products

Authors: Wu, Y; Wang, Y; Li, J; Dai, J; Lu, W; He, M; Dong, Z; Xu, W; Lv, L (2020) HERO ID: 6392505


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

The short-chain perfluorinated compounds PFBS, PFHxS, PFBA and PFHxA, disrupt human mesenchymal stem cell self-renewal and adipogenic differentiation

Authors: Liu, S; Yang, R; Yin, N; Faiola, F (2020) Journal of Environmental Sciences 88:187-199. HERO ID: 6315705

[Less] Per- and polyfluorinated alkyl substances (PFASs) are commonly used in industrial processes and daily . . . [More] Per- and polyfluorinated alkyl substances (PFASs) are commonly used in industrial processes and daily life products. Because they are persistent, they accumulate in the environment, wildlife and humans. Although many studies have focused on two of the most representative PFASs, PFOS and PFOA, the potential toxicity of short-chain PFASs has not yet been given sufficient attention. We used a battery of assays to evaluate the toxicity of several four-carbon and six-carbon perfluorinated sulfonates and carboxyl acids (PFBS, PFHxS, PFBA and PFHxA), with a human mesenchymal stem cell (hMSC) system. Our results demonstrate significant cyto- and potential developmental toxicity for all the compounds analyzed, with shared but also distinct mechanisms of toxicity. Moreover, the effects of PFBS and PFHxS were stronger than those of PFBA and PFHxA, but occurred at higher doses compared to PFOS or 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

Optimization and validation of a method based on QuEChERS extraction and liquid chromatographic-tandem mass spectrometric analysis for the determination of perfluoroalkyl acids in strawberry and olive fruits, as model crops with different matrix characteristics

Authors: Scordo, CVA; Checchini, L; Renai, L; Orlandini, S; Bruzzoniti, MC; Fibbi, D; Mandi, L; Ouazzani, N; Del Bubba, M (2020) HERO ID: 6326245

[Less] A QuEChERS method was optimized and validated for the LC-MS/MS analysis of perfluoro-n-pentanoic acid . . . [More] A QuEChERS method was optimized and validated for the LC-MS/MS analysis of perfluoro-n-pentanoic acid (PFPeA), perfluoro-1-butanesulfonic acid (PFBuS), perfluoro-n-hexanoic acid (PFHxA), perfluoro-n-heptanoic acid (PFHpA), perfluoro-1-hexanesulfonic acid (PFHxS), perfluoro-n-octanoic acid (PFOA), perfluoro-n-nonanoic acid (PFNA), perfluoro-1-octanesulfonic acid (PFOS) and perfluoro-n-decanoic acid (PFDA) in freeze-dried strawberry and olive, as model fruits characterized by very different chemical compositions. The method was evaluated for apparent recovery, intra-day and inter-day precision, matrix effect and recovery. The method optimized for strawberry provided for most compounds absolute values of matrix effect (|ME%|) ≤ 11%, except for PFHxA, which showed a signal suppression of 22%. The extraction efficiency was tested at the spike levels 500-5000 pg/g d.w. for PFPeA, PFBuS, and PFHxA, and 100-1000 pg/g d.w. for the other target analytes, evidencing as a whole recoveries in the range of 65-89%. For olive fruits, due to their high fat content, an ultrasound-assisted extraction was necessary to obtain an efficient sample disgregation so as to increase the extraction yield and its precision. Moreover, a d-SPE clean-up with GCB allowed to achieve |ME%| ≤ 8% (except for PFBuS, which showed a signal enhancement of 19%) and recoveries calculated at the aforementioned spike levels were in the range 75-97%. The two methods provided very good linearity (R2 ≥ 0.9984) from 10,000 pg/g down to compound specific quantification limits, which were included in the ranges of 2.9-393 pg/g and 2.6-127 pg/g for strawberry and olive fruit, respectively. The methods were applied to the analysis of PFAAs in strawberry and olive fruits commercially available in two Italian supermarkets, as well as obtained under irrigation with various treated wastewaters (TWWs), evidencing in both cases a higher PFAAs occurrence in olives than in strawberry. However, PFAAs concentrations determined in the investigated fruit matrixes were quite low, being their sum 1.9 ng/g d.w. in the worst case (i.e. olive fruits grown under irrigation with TWWs).

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

Contaminant levels and endocrine disruptive effects in Clarias gariepinus exposed to simulated leachate from a solid waste dumpsite in Calabar, Nigeria

Authors: Ibor, OR; Andem, AB; Eni, G; Arong, GA; Adeougn, AO; Arukwe, A (2020) Aquatic Toxicology 219:105375. HERO ID: 6311681

[Less] Solid waste dumpsites (SWDs) and landfills are significant sources of emerging contaminants to terrestrial . . . [More] Solid waste dumpsites (SWDs) and landfills are significant sources of emerging contaminants to terrestrial and aquatic ecosystems. We have studied the endocrine disruptive effects of simulated leachate from a solid waste dumpsite in Calabar, Nigeria. Juvenile C. gariepinus were exposed to simulated leachate, diluted to 0:0 (control), 1:10, 1:50, 1:100 for 3, 7 and 14 days. In addition, 17β-estradiol (E2: 100 μg/L)-exposed positive control group was included. Hepatic transcripts for the genes encoding vitellogenin (vtg), estrogen receptor-α (er-α), and aromatase (cyp19a1) were analyzed by real-time PCR. Protein expression for Vtg and Cyp19 were measured by immunoblotting and plasma steroid hormones (testosterone: T and E2) were measured using enzyme immunoassay (EIA). Soil samples from the dumpsite were analyzed for selected group of contaminants showing that DEHP was the only detected phthalate ester (PE) at 1300 ± 400 ng/g. Further, perfluoroalkyl substances (PFASs) such as PFBS, PFOS, PFHxA, PFOA, PFNA, PFDA, PFUnDA and PFDoDA were detected in the soil samples from the dumpsite. We observed significant and apparent concentration-dependent increases in mRNA (vtg, er-α, and cyp19a1) and their corresponding functional protein products, after exposure to the simulated leachates. Further, the simulated leachate produced concentration-specific changes in plasma E2 and T levels. In general, the estrogenic endocrine and reproductive alterations in the exposed fish may directly be attributed to the PFASs and DEHP detected at the dumpsites. However, in addition to PFASs and DEHP, there could be other estrogenic contaminants in the leachate. Given the rapid utilization, for residential purposes, and increases in human settlement in areas around the Lemna SWDs, this study provides a direct cause-and-effect evidence of the potential contaminants at the dumpsite with significant environmental and human health consequences.

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

A Self-Assembled Iron(II) Metallacage as a Trap for Per- and Polyfluoroalkyl Substances in Water

Authors: Fulong, CRP; Guardian, MGE; Aga, DS; Cook, TR (2020) HERO ID: 6311631

[Less] An anionic iron(II) tetrahedral molecular cage (FeMOP) was studied for its ability to interact with . . . [More] An anionic iron(II) tetrahedral molecular cage (FeMOP) was studied for its ability to interact with various per- and polyfluoroalkyl substances (PFASs) in aqueous media. Liquid chromatography tandem mass spectrometry revealed that longer-chain-length (more than six carbons) perfluorocarboxylic, -sulfonic, and fluorotelomers were removed from solution. In contrast, the steric bulk of N-ethyl substituted fluorosulfonamido acetic acid PFASs hindered association with the cage. Solution binding studies in D2O using 19F nuclear magnetic resonance (NMR) titrations and a Job plot show a 1:1 binding stoichiometry for perfluorohexanoic acid (PFHxA) and perfluoroheptanoic acid (PFHpA) with an association constant (Ka) of <103 and thus a favorable free energy of association (ΔG°). Perfluorononanoic acid (PFNA), on the other hand, forms an insoluble host-guest complex with FeMOP with a 1:1 host-guest ratio. Variable temperature (VT) NMR was used to determine the thermodynamic parameters of binding for a 1:1 FeMOP/PFHpA complex in water using a Curie-like model for fast-exchange processes. The extracted parameters suggest a low binding interaction (Ka < 103) driven by an increase in entropy from cage desolvation upon guest binding. The solid-state host-guest complexes formed from solution complexation of PFHxA, PFHpA, and PFNA into the cage were characterized by infrared spectroscopy (FT-IR) and powder X-ray diffraction (PXRD) methods. FT-IR studies suggest an interaction between the fluorocarbon groups of PFASs to the phenylsulfonate functional groups of the ligand. A docking model predicted by computation also indicates this interaction may occur, with the PFASs adsorbing onto the surface of the cage rather than forming a true host-guest complex within the internal cavity. PXRD studies reveal a crystal packing of the complex that is very similar to that of the water-treated FeMOP, with the exception of 1:2 FeMOP/PFNA and 1:1 and 2:1 FeMOP/PFHpA.

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

Determinants of serum concentrations of perfluoroalkyl acids (PFAAs) in school children and the contribution of low-level PFAA-contaminated drinking water

Authors: Glynn, A; Kotova, N; Dahlgren, E; Lindh, C; Jakobsson, K; Gyllenhammar, I; Lignell, S; Nälsén, C (2020) Environmental Science: Processes & Impacts. HERO ID: 6315696

[Less] Little is known about the demographic/life-style/physiological determinants explaining the variation . . . [More] Little is known about the demographic/life-style/physiological determinants explaining the variation of serum perfluoroalkyl acid (PFAA) concentrations in children. We identified significant determinants in children and investigated the influence of low-level PFAA-contaminated drinking water (DW) (<10 ng L-1 of single PFAAs) on serum concentrations. Four perfluorosulfonic acids (PFSAs) and 11 perfluorocarboxylic acids (PFCAs) were analyzed in serum from 5th grade children from 11 Swedish schools (N = 200; average age: 12 years) using liquid chromatography-tandem-mass-spectrometry. Data on demography and life-style/physiological factors were obtained by questionnaires. PFAA concentrations in raw and drinking water (DW) were obtained from the water works supplying DW to the schools. In multiple regression analyses school was the determinant contributing most to the variation in PFAA concentrations, with the lowest contribution for PFHpA (10%) and the highest for PFHxS (81%). Girls had lower adjusted mean concentrations of PFHxS, PFOS, PFNA and PFDA than boys, but a higher concentration of PFHxA. Girls reporting onset of menstruation had lower PFHxS and PFOA concentrations than other girls, suggesting menstrual bleeding elimination. Children born by mothers from less industrialized countries had lower mean concentrations of both PFSAs and PFCAs than children with mothers from highly industrialized countries, suggesting differences in early-life exposure. Life-style factors associated with paternal education levels appeared to influence PFAA concentrations differently than maternal education level. Already at an average DW PFHxS concentration of 2 ng L-1, children had a significantly higher adjusted mean serum PFHxS concentration than at an average DW concentration of <1.6 ng PFHxS L-1. Similar results were observed for PFOS and PFOA. The DW variable explained 16% (PFOA) to 78% (PFHxS) of the variation in serum PFAA concentrations, suggesting that low-level-contaminated DW is a significant source of exposure for children in Sweden. Although some of the associations, especially those with menstruation and maternal birth country, should be interpreted with extra caution due to the small size of the study, the results contribute to future work on identifying populations of children at risk of elevated PFAA exposures.

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

Behavioural effects and bioconcentration of per- and polyfluoroalkyl substances (PFASs) in zebrafish (Danio rerio) embryos

Authors: Menger, F; Pohl, J; Ahrens, L; Carlsson, G; Örn, S (2020) Chemosphere 245:125573. HERO ID: 6311635

[Less] Per- and polyfluoroalkyl substances (PFASs) are contaminants of emerging concern (CECs) that cause concern . . . [More] Per- and polyfluoroalkyl substances (PFASs) are contaminants of emerging concern (CECs) that cause concern regarding their environmental impact and risk to human health. In this study, zebrafish (Danio rerio) embryos were exposed to PFASs for six days, to investigate behaviour toxicity and bioconcentration factor (BCF). Nine individual PFASs (five C4-C8 perfluoroalkyl carboxylates (PFCAs) (PFPeA, PFHxA, PFHpA, PFOA, PFNA), three C4, C6 and C8 perfluoroalkyl sulfonates (PFSAs) (PFBS, PFHxS, PFOS) and 6:2 fluorotelomersulfonate (6:2 FTSA)) and a mixture of these were investigated at seven concentrations ranging from environmentally relevant to acutely toxic levels. In exposed embryos, significant differences were found in total swimming distance (PFHpA, PFOA, PFNA, PFHxS, PFOS, 6:2 FTSA, PFAS mixture), burst activity (PFOA, PFNA, PFHxS, PFOS, PFAS mixture) and startle response (PFNA, PFHxS, PFOS, PFAS mixture). Toxicity was only observed at concentrations well above environmental levels. The toxicity of the PFAS mixture generally followed that of the individual substances, but the mixture reduced the potencies of individual PFASs. BCF was determined for all nine PFASs and ranged between 0.9 (PFPeA) and 2700 (PFOS). Long-chain PFASs (C8) and PFASs with sulfonate as an active group showed the greatest toxic potential, while short-chain PFASs (C6 and C7) also caused significant behaviour alterations and accumulated in the embryos. To our knowledge, this is the first study to compare the behaviour toxicity of a PFAS mixture with that of the individual PFASs. Follow-up studies are needed to identify the mechanistic responses to PFAS mixtures.