Health & Environmental Research Online (HERO)


Per- and Polyfluoroalkyl Substances (PFAS)


1,107 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

Use of high-throughput in vitro toxicity screening data in cancer hazard evaluations by IARC Monograph Working Groups

Authors: Chiu, WA; Guyton, KZ; Martin, MT; Reif, DM; Rusyn, I (2018) Altex 35:51-64. HERO ID: 3981309

[Less] Evidence regarding carcinogenic mechanisms serves a critical role in International Agency for Research . . . [More] Evidence regarding carcinogenic mechanisms serves a critical role in International Agency for Research on Cancer (IARC) Monograph evaluations. Three recent IARC Working Groups pioneered inclusion of the US Environmental Protection Agency (EPA) ToxCast program high-throughput screening (HTS) data to supplement other mechanistic evidence. In Monograph V110, HTS profiles were compared between perfluorooctanoic acid (PFOA) and prototypical activators across multiple nuclear receptors. For Monograph V112 -113, HTS assays were mapped to 10 key characteristics of carcinogens identified by an IARC expert group, and systematically considered as an additional mechanistic data stream. Both individual assay results and ToxPi-based rankings informed mechanistic evaluations. Activation of multiple nuclear receptors in HTS assays showed that PFOA targets peroxisome proliferator activated and other receptors. ToxCast assays substantially covered 5 of 10 key characteristics, corroborating literature evidence of "induces oxidative stress" and "alters cell proliferation, cell death or nutrient supply" and filling gaps for "modulates receptor-mediated effects." Thus, ToxCast HTS data were useful both in evaluating specific mechanistic hypotheses and in the overall evaluation of mechanistic evidence. However, additional HTS assays are needed to provide more comprehensive coverage of the 10 key characteristics of carcinogens that form the basis of current IARC mechanistic evaluations.

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

Riverine inputs and source tracing of perfluoroalkyl substances (PFASs) in Taihu Lake, China

Authors: Ma, X; Shan, G; Chen, M; Zhao, J; Zhu, L (2018) Science of the Total Environment 612:18-25. HERO ID: 3981684

[Less] The occurrence, riverine inputs and sources of perfluoroalkyl substances (PFASs) in Taihu Lake, one . . . [More] The occurrence, riverine inputs and sources of perfluoroalkyl substances (PFASs) in Taihu Lake, one of the largest lakes in China, were investigated by measuring PFASs including the isomers of perfluorooctanesulfonate (PFOS), perfluorooctanoate (PFOA) and perfluorohexanesulfonate (PFHxS) in the Lake and its main flow-in rivers. It was found that PFHxS, instead of PFOS or PFOA, was predominant both in the Lake and rivers (45.9-351ng/L), reflecting increasing demand of PFHxS in recent years. The riverine flux of PFASs into the Lake was estimated to be 1255kg/year. The percentage of linear (n-) PFOS and the ratio of 3+5m-/1m-PFOS were combined to indicate indirect source due to biodegradation of PFOS-precursors. The percentage order of n-PFOS was: the Lake (48.7%)the rivers (8.99)>ECF (electrochemical fluorination) product (6.76). These suggested that degradation of PFOS-precursors made distinct contribution to PFOS load in the waters, particularly in the Lake. The Lake and river waters had a consistent proportion of n-PFHxS (89.0%), which was slightly lower than the ECF product (96.0%), indicating it was mainly due to the release from production and application of PFHxS as an active ingredient.

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

High perfluorooctanoic acid exposure induces autophagy blockage and disturbs intracellular vesicle fusion in the liver: Supplementary materials

Authors: Yan, S; Zhang, H; Guo, X; Wang, J; Dai, J (2017) Archives of Toxicology 91. [Supplemental Data] HERO ID: 3986361

Abstract: Supplementary materials

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

Coupling sweeping-micellar electrokinetic chromatography with tandem mass spectrometry for the therapeutic monitoring of benzimidazoles in animal urine by dilute and shoot

Authors: Tejada-Casado, C; Moreno-González, D; Del Olmo-Iruela, M; García-Campaña, AM; Lara, FJ (2017) Talanta 175:542-549. HERO ID: 3981273

[Less] A new method based on micellar electrokinetic chromatography-tandem mass spectrometry (MEKC-MS/MS) has . . . [More] A new method based on micellar electrokinetic chromatography-tandem mass spectrometry (MEKC-MS/MS) has been developed for the identification and simultaneous quantification of thirteen benzimidazoles in animal urine. In order to obtain an appropriate separation with the highest sensitivity, different electrophoretic parameters were evaluated. Under optimum conditions, the separation was performed using ammonium perfluorooctanoate as volatile surfactant and electrophoretic buffer (50mM, pH 9). To increase the sensitivity, a stacking mode named sweeping was applied, using water as injection solvent at 50mbar for 75s, obtaining sensitivity enhancement factors from 50 to 181. The method was applied to different animal urine samples, including sheep, cow and goat. The sample treatment consisted of a 1:10 (v/v) dilution with water. Calibration using sheep urine samples can be used for both goat and cow urine samples with a relative bias below 25% and relative standard deviations lower than 8%. The limits of detection were below 70µgL(-1). As a result, the applicability of this rapid, simple, sensitive, and environmentally friendly method for therapeutic drug monitoring of benzimidazoles based on the analysis of animal urine has been demonstrated.

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

Adsorptive removal of emerging polyfluoroalky substances F-53B and PFOS by anion-exchange resin: A comparative study

Authors: Gao, Y; Deng, S; Du, Z; Liu, K; Yu, G (2017) Journal of Hazardous Materials 323:550-557. HERO ID: 3845321

[Less] Chrome plating is an important emission source of perfluorinated compounds (PFCs) industrial uses in . . . [More] Chrome plating is an important emission source of perfluorinated compounds (PFCs) industrial uses in China, where two commercial products potassium 2-(6-chloro-1,1,2,2,3,3,4,4,5,5,6,6-dodecafluorohexyloxy) (F-53B) and perfluorooctane sulfonate (PFOS) are applied as mist suppressant, causing non-negligible environmental risk. In this paper, anion-exchange resin IRA67 was evaluated for F-53B and PFOS removal from simulated and actual wastewater. Adsorption kinetics exhibited higher adsorption velocity and capacity of IRA67 for PFOS than F-53B due to their difference in molecular structures. Adsorption isotherms demonstrated the adsorption capacity of F-53B and PFOS on IRA67 was 4.2mmol/g and 5.5mmol/g, respectively. Because of the deprotonating of amine groups, solution pH had significant effect on IRA67 at pH>10. The results indicated that besides anion exchange other interactions including hydrophobic interaction and the formation of micelles or hemi-micelles were all involved in adsorption process. Coexisting sulfate and chromate in wastewater decreased adsorption capacities of F-53B and PFOS. The spent resin could be regenerated by the NaCl/NaOH and methanol mixed solution. In the mixed system and actual wastewater IRA67 can simultaneously remove F-53B and PFOS without obvious preference but the removal percent can be affected by competitive effect.

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 impacts of emission trends of POPs on human concentration dynamics: Lessons learned from a longitudinal study in Norway (1979-2007)

Authors: Nøst, TH; Sandanger, TM; Nieboer, E; Odland, JØ; Breivik, K (2017) International Journal of Hygiene and Environmental Health 220:776-781. HERO ID: 3602916

[Less] BACKGROUND: In this short communication, our focus is on the relationship between human . . . [More] BACKGROUND: In this short communication, our focus is on the relationship between human concentrations of select persistent organic pollutants (POPs) and environmental emissions. It is based on a longitudinal study (1979-2007) conducted in Norway.

OBJECTIVES: Our aim was to extract general insights from observed and predicted temporal trends in human concentrations of 49 POPs to assist in the design and interpretation of future monitoring studies.

DISCUSSION: Despite considerable decline for polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) since 1986, the sum of the targeted POPs increased from 1979 until 2001, with per- and polyfluorinated alkyl substances (PFASs) dominating recent blood burden measurements. Specifically, the time trends in serum concentrations of POPs, exemplified by PCB-153, 1,1'-(2,2,2-Trichloroethane-1,1-diyl)bis(4-chlorobenzene) (DDT) and perfluorooctane sulfonic acid (PFOS), resembled the trends in available data on their emissions, production or use. These observations suggest that interpretations of human biomonitoring data on persistent compounds must consider historic emissions, which likely vary spatially across the globe. Based on the different temporal trends observed across POP groups, it is evident that generalizations regarding temporal aspects have limitations.

CONCLUSION: The discussion herein underscores the importance of understanding temporal variations in environmental emissions when designing and interpreting human biomonitoring studies.

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

Occurrence and inputs of perfluoroalkyl substances (PFASs) from rivers and drain outlets to the Bohai Sea, China

Authors: Chen, H; Wang, X; Zhang, C; Sun, R; Han, J; Han, G; Yang, W; He, X (2017) Environmental Pollution 221:234-243. HERO ID: 3856462

[Less] Concentrations of 19 PFASs in riverwater, coastal wastewater and effluents from WWTPs which were directly . . . [More] Concentrations of 19 PFASs in riverwater, coastal wastewater and effluents from WWTPs which were directly discharged into the Bohai Sea of China were measured and their inputs to this sea area were calculated accordingly. For riverwater samples, the total PFAS concentrations ranged from 13.1 to 69 238 ng/L. PFAS levels in riverwater collected from Liaoning Province were comparable to those from Shandong Province, while they were two orders of magnitude greater than those from Hebei Province and the city of Tianjin. The dominant PFAS patterns were spatially different. PFBS and PFOA were the predominant PFASs in riverwater samples at sites where fluorochemical industry parks are located in Liaoning Province and Shandong Province, respectively. For other sites, PFOA and PFOS were the most abundant PFASs. In contrast, the total PFAS concentrations in coastal wastewater and effluent samples ranged from 16.7 to 7 522 ng/L and from 13.1 to 319 ng/L, respectively. PFOA was dominant in these samples. Inputs of PFASs to the Bohai Sea via riverine flow, discharge of coastal wastewater and effluents were estimated to be 87.3 tons per year. As compared with coastal wastewater and effluent discharge, riverine input was a major source for the PFAS pollution in the Bohai Sea except for PFBS.

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

Mixture-specific gene expression in zebrafish (Danio rerio) embryos exposed to perfluorooctane sulfonic acid (PFOS), perfluorohexanoic acid (PFHxA) and 3,3',4,4',5-pentachlorobiphenyl (PCB126)

Authors: Blanc, M; Kärrman, A; Kukucka, P; Scherbak, N; Keiter, S (2017) Science of the Total Environment 590-591:249-257. HERO ID: 3859704

[Less] Perfluorooctane sulfonic acid (PFOS) and 3,3',4,4',5-pentachlorobiphenyl (PCB126) are persistent organic . . . [More] Perfluorooctane sulfonic acid (PFOS) and 3,3',4,4',5-pentachlorobiphenyl (PCB126) are persistent organic pollutants of high concern because of their environmental persistence, bioaccumulation and toxic properties. Besides, the amphiphilic properties of fluorinated compounds such as PFOS and perfluorohexanoic acid (PFHxA) suggest a role in increasing cell membrane permeability and solubilizing chemicals. The present study aimed at investigating whether PFOS and PFHxA are capable of modifying the activation of PCB126 toxicity-related pathways. For this purpose, zebrafish embryos were exposed in semi-static conditions to 7.5μg/L of PCB126 alone, in the presence of 25mg/L of PFOS, 15.7mg/L of PFHxA or in the presence of both PFOS and PFHxA. Quantitative PCR was performed on embryos aged from 24h post fertilization (hpf) to 96 hpf to investigate expression changes of genes involved in metabolism of xenobiotics (ahr2, cyp1a), oxidative stress (gpx1a, tp53), lipids metabolism (acaa2, osbpl1a), and epigenetic mechanisms (dnmt1, dnmt3ba). Cyp1a and ahr2 expression were significantly induced by the presence of PCB126. However, after 72 and 78h of exposure, induction of cyp1a expression was significantly lower when embryos were co-exposed to PCB126+PFOS+PFHxA when compared to PCB126-exposed embryos. Significant upregulation of gpx1a occurred after exposure to PCB126+PFHxA and to PCB126+PFOS+PFHxA at 30 and 48 hpf. Besides, embryos appeared more sensitive to PCB126+PFOS+PFHxA at 78 hpf: acaa2 and osbpl1a were significantly downregulated; dnmt1 was significantly upregulated. While presented as environmentally safe, PFHxA demonstrated that it could affect gene expression patterns in zebrafish embryos when combined to PFOS and PCB126, suggesting that such mixture may increase PCB126 toxicity. This is of particular relevance since PFHxA is persistent and still being ejected into the environment. Moreover, it provides additional information as to the importance to integrate mixture effects of chemicals in risk assessment and biomonitoring frameworks.

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

Isomer-specific transplacental transfer of perfluoroalkyl acids: Results from a survey of paired maternal, cord sera, and placentas

Authors: Chen, F; Yin, S; Kelly, BC; Liu, W (2017) Environmental Science and Technology 51:5756-5763. HERO ID: 3859806

[Less] Currently, information regarding isomer-specific concentrations of PFHxS, PFOS, and PFOA in human placenta, . . . [More] Currently, information regarding isomer-specific concentrations of PFHxS, PFOS, and PFOA in human placenta, and corresponding placental-maternal ratios (RPM) of these compounds does not exist. The objective of the present study was to assess the occurrence, and distribution of different PFHxS, PFOS, and PFOA isomers in maternal serum, umbilical cord serum, and placenta to gain a better understanding of transplacental transport efficiency and prenatal exposure risks. The study involved quantitative determination of isomer-specific concentrations of PFHxS, PFOS, and PFOA in samples of maternal serum (n = 32), cord serum (n = 32), and placenta (n = 32) from pregnant women in Wuhan, China. The results indicate that both linear and branched PFHxS, PFOS and PFOA can be efficiently transported across the placenta, with exposure levels ordered maternal serum > cord serum > placenta. For PFOS isomers, the concentration ratios between cord serum and maternal serum (RCM) were ordered n < iso < 4m < (3 + 5)m < 1m < ∑m2. The RPM values exhibited a similar trend for branched PFOS isomers: iso < 4m ≈ (3 + 5)m < 1m ≈ ∑m2. Conversely, PFOA isomers did not exhibit an obvious structure-activity relationship for RCM and RPM. n-PFHxS transported across the placenta to a greater extent than br-PFHxS. To the best of our knowledge, this is the first study to report the occurrence of PFHxS, PFOS, and PFOA isomers in human placenta. Further, RPM values of these compounds are reported here for the first time. The findings help to better understand the mechanisms of the placental transfer and neonatal exposure to these important contaminants of concern.

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

Perfluorooctanesulfonate (PFOS) Conversion from N-Ethyl-N-(2-hydroxyethyl)-perfluorooctanesulfonamide (EtFOSE) in male Sprague Dawley rats after inhalation exposure

Authors: Chang, S; Mader, BT; Lindstrom, KR; Lange, CC; Hart, JA; Kestner, TA; Schulz, JF; Ehresman, DJ; Butenhoff, JL (2017) Environmental Research 155:307-313. HERO ID: 3860242

[Less] Ethyl-N-(2-hydroxyethyl)-perfluorooctanesulfonamide (EtFOSE) was one of the key building blocks for . . . [More] Ethyl-N-(2-hydroxyethyl)-perfluorooctanesulfonamide (EtFOSE) was one of the key building blocks for many of the perfluorooctanesulfonyl-based chemistry and laboratory studies have shown that EtFOSE can metabolically degrade to perfluorooctanesulfonate (PFOS). Non-occupational contribution sources to PFOS are thought to occur in general population via diets, drinking water, air and dust. For workers, however, the exposure route was mostly airborne and the exposure source was predominantly to precursor compounds such as EtFOSE. We undertook this study to investigate how much EtFOSE was converted to PFOS in the serum for male rats after 6h of exposure to EtFOSE vapor (whole body) at ambient temperature, which simulated a work place exposure scenario. There were no abnormal clinical observations and all rats gained weight during study. Interim tail-vein blood samples, collected up to 21 days after exposure, were analyzed for Et-FOSE and PFOS concentrations by LC-MS/MS. Upon inhalation exposure, the biotransformation of EtFOSE to PFOS in serum in the male rats was rapid and very little EtFOSE was detected in the serum within 24h after EtFOSE exposure. The highest conversion to PFOS in serum after exposure to EtFOSE vapor appeared to occur between Day 8-14 post exposure. Considering the potential surface and fur adsorption of test compound in the whole-body exposure system, our data would support that at least 10% of the inhaled EtFOSE was biotransformed to PFOS in the serum based on the range of lower 95% CI (confidence interval) values. This information is valuable because it quantitatively translates EtFOSE exposure into serum PFOS concentration, which serves as a matrix for internal dosimetry (of PFOS exposure) that can be used as an anchor across species as well as between different exposure routes.