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Corporate Influence and the PFAS Contamination CrisisZhao, Meriel January 2024 (has links)
Thesis advisor: Juliet Schor / This study explores the dynamics of legislative conflicts surrounding PFAS (per- and polyfluoroalkyl substances) regulation in Massachusetts, focusing on the strategies employed by industry representatives and pro-regulatory advocates giving testimony at public hearings. Through a qualitative analysis of hearing transcripts and testimonies, the study reveals two primary lobbying strategies: an appeal to a status quo bias by emphasizing economic burdens and a "splitting hairs" tactic that emphasizes scientific nuances to advocate for a risk-based approach to regulation. In contrast, pro-regulatory advocates highlighted the known risks of PFAS exposure and served as foils to industry narratives. The study highlights the strategic communication tactics used by interest groups to influence policymakers and sheds light on the complex landscape of environmental regulatory debates in Massachusetts, emphasizing the role of public interest groups in countering the influence of private interest groups. / Thesis (BA) — Boston College, 2024. / Submitted to: Boston College. Morrissey School of Arts and Sciences. / Discipline: Sociology. / Discipline: Scholar of the College.
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Evaluation of the Removal Efficiency of Perfluoroalkyl Substances in Drinking WaterEnglund, Sophie January 2015 (has links)
Per- and polyfluoroalkyl substances (PFASs) are chemicals that have been used for over 50 years. They are both hydrophobic and hydrophilic, which make them useful in a wide range of products, both in the domestic and industrial market. Recently, the global attention on PFASs has increased due to their possible harmful health effects on humans. Furthermore, PFASs have been detected in drinking water sources all over the world. Conventional treatment processes in drinking water treatment plants (DWTPs) are not able to remove PFASs. Therefore, more research is required to find efficient removal techniques for these compounds. The aim of this study was to investigate the removal efficiency of PFASs using two different adsorption techniques, anion exchange (AE) with the resin Purolite A-600, and granular activated carbon (GAC) of type Filtrasorb®400. The experiments were performed in laboratory batch-scale, at Swedish University of Agriculture (SLU), and column tests in pilot-scale, at Bäcklösa DWTP in Uppsala. The PFASs showed a high sorption potential to AE and GAC. However, the removal efficiency differed depending on the perfluorocarbon chain length, functional group, and concentration level. For the AE, in average 92 % of the PFASs were removed in the end of the batch experiments while the average removal efficiency in the column experiment was 86 %. In the batch experiments treated with GAC on average 55 % of the PFASs were removed in the end of the experiments while the column experiment had the average removal efficiency of 86 %. There was an increase in the removal efficiency with increasing perfluorocarbon chain length in the column experiments. However, in the batch experiments, the adsorption of PFASs decreased with an increasing chain length, except for the highest PFAS concentration level (5000 ng L-1) treated with AE and the lowest PFAS concentration level (200 ng L-1) treated with GAC. In the column experiments, the perfluoroalkane sulfonates (PFSAs) were slightly better removed than perfluoroalkyl carboxylates (PFCAs) with an average removal efficiency of 97 % for AE and 91 % for GAC compared to 67 % and 82 % for AE and GAC, respectively. In the batch experiments, there was no clear trend between the removal efficiency and functional group. Overall, the pilot-scale experiments removed the PFASs relatively well even after 42 days (on average, 86 % for both AE and GAC). The lowest removal capacity in the column experiments was seen for the shorter chained PFSAs (in average 46 % for ≤C6 PFCAs using AE and 75 % for ≤C7 PFCAs using GAC). More efficient treatment techniques are needed to minimise the PFAS concentrations in drinking water and the potential human. / Per- och polyfluorerade alkylsubstanser (PFASs) är kemikalier som har används globalt under de senaste 50 åren. Tack vare att de är uppbygda av både en hydrofob och en hydrofil del är de ytaktiva (s.k. surfaktanter) och har ett brett användningsområde, både för industri- och hushållsprodukter. På senare år har dessa ämnen fått uppmärksamhet på grund av att exponering för PFASs har visats kunna medföra hälsorisker. PFASs har upptäckts i dricksvatten på många håll i världen, men flera av de konventionella reningsmetoderna för dricksvatten är inte effektiva för PFASs och därför finns ett behov av mer forskning och kunskap inom vattenberedningsområdet. I denna studie undersöktes reningseffektiviteten för PFASs hos två adsorptionstekniker; i) anjonbyte (AE) med Purolite A-600 och ii) granulerat aktivt kol (GAC) med Filtrasorb®400. Studien utformades så att inverkan av kolkedjans längd, molekylens funktionella grupp samt koncentrationsnivån av PFASs kunde utvärderas. Experimenten utfördes både i liten skala genom försök i bägare på Sveriges lantbruksuniversitet (SLU) och i något större skala i en pilotanläggning med kolonnexperiment på Bäcklösa dricksvattenverk i Uppsala. Båda reningsmetoderna visade god effekvititet för avlägsnandet av PFASs i dricksvatten. I slutet av bägarexperimenten var i medeltal 92 % och 55 % av PFASs eliminerade för de prover behandlade med AE respektive GAC. Reningseffektivititen för kolonnexperimenten var i medeltal 86 % för båda metoderna. Reningsgraden var beroende av längden på den perfluorerade kolkedjan. I kolonnexperimenten visades att ökad kedjelängd ledde till ökad reningseffektivitet, medan bägarexperimenten visade på motsatt trend, med undantag för prover behandlades med AE och PFAS-koncentration 5000 ng L-1 samt prover behandlade med GAC och PFAS-koncentration 200 ng L-1. Reningseffektiviteten varierade också beroende på funktionell grupp, d.v.s. beroende på om det var en sulfonat eller en karboxylat. I kolonnexperimenten avlägsnades de perfluorerade alkylsulfonaterna (PFSAs) i något högre grad (97 % och 91 %; AE och GAC) än karboxylaterna (PFCAs; 67 % och 82 %; AE och GAC). För bägarexperimenten hittades dock inget tydligt motsvarande samband. Sammanfattningsvis renades PFASs från dricksvattnet i kolonnexperimenten relativt väl även i slutet av experimentent (efter 42 dagar). De sämst renade PFAS ämnena var de med kortare kolkedja. Efter 42 dagar hade PFCAs med kolkedjelängd ≤C6 renats bort med 46 % (AE) och på PFCAs med kolkedjelängd ≤C7 med 75 % (GAC). Behovet av bättre reningsmetoder för dessa PFASs är därför stort.
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Study on Suspect and Non-Target Screening of Per- and Polyfluoroalkyl Substances (PFASs) by Ion Mobility Mass Spectrometry / イオンモビリティ質量分析によるペルおよびポリフルオロアルキル物質(PFASs)の Suspect and Non-Target Screening に関する研究Yukioka, Satoru 23 March 2020 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(地球環境学) / 甲第22617号 / 地環博第196号 / 新制||地環||38(附属図書館) / 京都大学大学院地球環境学舎地球環境学専攻 / (主査)教授 藤井 滋穂, 教授 梶井 克純, 准教授 田中 周平 / 学位規則第4条第1項該当 / Doctor of Global Environmental Studies / Kyoto University / DFAM
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Rejection Properties of Perfluorohexanoic Acid in Various Aqueous Media by Polyamide and Sulfonated Polyethersulfone Nanofiltration Membranes / ポリアミドおよびスルホン化ポリエーテルスルホン系NF膜による種々の水溶液中のぺルフルオロヘキサン酸の除去特性に関する研究Zeng, Chenghui 25 September 2017 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第20692号 / 工博第4389号 / 新制||工||1682(附属図書館) / 京都大学大学院工学研究科都市環境工学専攻 / (主査)教授 田中 宏明, 教授 高岡 昌輝, 教授 藤井 滋穂 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DGAM
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The Role of Perfluoroalkyl Substances (PFAS) contaminated food for male infertility : A Scoping reviewKamran, Tehseen January 2023 (has links)
Background: The trend of male infertility is increasing and it correlates with industrial development which has introduced various industrial contaminants in the environment and human life. PFASs are one of those contaminants. Humans are exposed to PFAS through various routes and sources, especially through food and diet. On the other hand, some foods are beneficial for the male reproductive system. Aim: The study aim is to investigate the role of per-or poly-fluoroalkyl substances (PFASs) contaminated food in male infertility. Method: This study has used scoping review to assess the current knowledge concerning the aim that what has been done in this field. A systematic search was done in three databases namely PubMed, Web of Science, and Scopus, as well as manual search of related articles and reference lists during March-April 2023, and found 68 articles. Inclusion criteria included all articles written in English, related to humans, and PFAS exposure to adult males through food worldwide. Articles related to only the female population, other non-human species, human exposure to PFAS in fetal life, molecular level information, information about transport mechanisms of PFAS in food, other environmental contaminants and with no food contamination, toxicological, or health impact information were excluded. Titles, abstracts, and selected full-length articles were read and evaluated. CEBMa checklist for critical appraisal of the cross-sectional study, CASP checklist for systematic review, and randomized control trial were used as quality assessments of articles. Results: In total 68 abstracts were initially found, of which 15 were included in the review. Majority of the studies were either from Europe (European panel data from 16 different European countries) (n=2) or any European country (Italy=2, Georgia=1, Denmark=1, Sweden=1, Spain=1, Denmark + Sweden=1, Denmark + USA + Faroe Islands=1) and the rest were from USA (n=2), Australia (n=2) and Peru (n=1). The articles were analyzed according to the concept combinations of PFAS, food, or male fertility. Out of 15 included studies 3 deals with Pfas in food, 8 with Pfas and male fertility, 2 with male infertility related to PFAS in food, 1 with diet and human PFAS levels, and 1 with relation of food to male fertility. The articles included were of either good or moderate quality. Studies related to the direct impact of PFAS through food on male fertility are scarce. According to most of studies, PFASs have a significant impact on male hormones and sperm morphology but there was no significant association was found between PFAS levels to other seminal parameters. The combination of different PFAS and the combination of PFAS with other contaminants may alter the impact on male fertility. PFAS may have a long-term effect on human spermatogonial cells. Mediterranean diet is associated with high serum levels of PFAS in humans. Fish is a major source of PFAS exposure through food. 8 oz. of fish is recommended without causing health hazards, provided thatthe levels of PFAS contaminations in fish are not high. Conclusion: More studies especially longitudinal studies concerning PFAS exposure through food and its impact on male fertility are needed. No studies are found from the African continent and low-income countries. There is a need to check the levels of contamination of PFAS in food so that the health impacts on male fertility can be avoided.
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Human Exposure to Per- and Polyfluoroalkyl : Substances through Fish ConsumptionNauta, Welmoed January 2023 (has links)
Human exposure to per- and poly-fluoroalkyl substances (PFAS) occurs mainly through two pathways, inhalation and ingestion. Dietary exposure to persistent organic pollutants (POPs), including PFAS, is driven mainly by the consumption of foods of marine or terrestrial animal origin. Therefore, the intake of fish from waters in populated or polluted areas may be a source of human exposure to PFAS. The overall aim of the study was to estimate human exposure to PFAS through the consumption of fish caught in Swedish waters. Analyses of extractable organofluorine (EOF) were performed to serve as an important metric alongside target analysis to better understand the total amount of PFAS in the human sera and fish samples. The serum samples represent individuals who have lived at some point about 5 km from the glass industry in Nybro and Emmaboda. For this study with the Glasbruket study population, the highest concentrations were found for PFOS followed by PFOA, PFNA and PFHxS (medians of 7.9, 1.9, 1.4 and 0.8 ng/mL). Also, the difference in this population between men/women and high/low fish consumers were also addressed. It was stated that there was a statistically significant difference in average Σ17 PFAS concentration between the male and female groups (p < 0.05, two-tailed test). However, the differences between the low and high consumer groups were not statistically significant even though the PFAS levels were higher in the high consumer group. The organofluorine mass balance analysis revealed that 80.1% (ranged from 68.3−93.7%) of the EOF in female samples could not be explained, whereas 57.3% (ranged from 0−99.4%) for the male group was of unidentified origin. Two methods were evaluated for PFAS and EOF analysis of fish muscle, namely, acetonitrile extraction and ion-pair extraction. The selected method, the ion-pair extraction, was performed on fish muscle samples. The fish species included perch (Perca fluviatilis), northern pike (Esox Lucius) and zander (Sander lucioperca) that were collected from seven different lakes in the vicinity of Nyro and Emmaboda. The sum of targeted PFAS (∑14PFAS) across all fish samples analysed ranged from 0.9 to 6.2 ng/g. Mostly, perfluoroalkyl carboxylic acids (PFCAs), precursors to PFCAs and novel PFAS were found in the fish samples. A large part of the EOF content cannot be identified with the targeted PFAS compounds. The average identified EOF fraction for all fish was 2.3% (ranging from 0.8 to 7.2%). For this study, 10 PFAS were found in both sera and fish samples. Therefore, freshwater fish consumption can be identified as one of the contributors to the PFAS concentrations in the Glasbruket population. The fish samples contained precursor compounds as well, that were not found in human serum. These precursor compounds can contribute to the concentrations of PFAAs in serum through biotransformation in the human body to perfluoroalkyl acids (PFAAs). Due to the widespread use of PFAS and their persistence in the environment, it is difficult to determine the relationship between the levels found in serum and fish. The Glasbruket population could be exposed to other sources besides fish.
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Determination of PFAS compounds in human serum using laminar flow tandem mass spectrometryHaynes, Halia Heather 02 February 2023 (has links)
Per- and polyfluoroalkyl substances (PFAS) encompass a large group of manufactured compounds that have been used in various production processes such as food packaging, commercial products, workplaces, homes, water supplies, and food. PFAS are persistent, resistant to degradation, and can bioaccumulate. Although an exposure limit that predicts adverse health effects has yet to be determined, the Center for Disease Control and Prevention’s 2015-16 health survey found average blood levels of 4.72 ng/ml for PFOS and 1.56 ng/ml for PFOA.
The objective of this research was to evaluate the use of laminar flow tandem mass spectrometry following solid phase extraction (SPE) using weak anion exchange (WAX) properties on the detection and quantitation of PFAS compounds.
Seven-point calibration standards applied to this research were prepared using certified reference materials (Wellington Laboratories, Ontario, CA), and calibrators were run without sample extraction. The concentrations varied slightly based on the PFAS analyte of interest. All samples and quality controls were prepared by spiking certified reference material (Wellington Laboratories) into pooled human serum (BioIVT, Westbury, NY, USA). A laminar flow QSight®220 ultra-high pressure liquid chromatography-tandem mass spectrometer (LC-MS/MS, PerkinElmer, Waltham, MA, USA) was equipped with a Selectra C18 100 x 2.1mm x 3μm (UCT, Bristol, PA, USA) column with a Brownlee C18 delay column (PerkinElmer) and followed the LC-MS/MS parameters developed for the method. Extraction was accomplished using a WAX SPE column (UCT, ECWAX053) by first conditioning the columns with 1 mL of methanol (Fisher Scientific, Fair Lawn, NJ, USA) followed by 1 mL of 100 mM pH 7 phosphate buffer (Acros Organics, Geel, Belgium, EU). Samples were loaded onto the column at a rate of 1-2 mL/min. The SPE cartridges were washed with 1 mL of 100 mM pH 7 phosphate buffer and 1 mL of millipore water (Millipore Milli- Q Ultrapure Type 1 water system, Millipore Sigma, Burlington, MA, USA), then dried under full flow for 5 minutes. Elution was carried out with 2.5mL of a 98:2 methanol: OptimaTM grade ammonium hydroxide (Fisher Scientific) solution. The eluted samples were then evaporated to dryness using a MULTIVAP® Nitrogen Evaporator (Organomation,Berlin,MA,USA) at 55°C and 5psi. All samples were reconstituted in 100 μL of a 96:4 methanol:water solution. The parameters assessed followed Academy Standards Board Standard 036: Standard Practices for Method Validation in Forensic Toxicology, including matrix interferences, limit of detection (LOD), limit of quantitation (LOQ), a recovery study, and a calibration model.
The results of the study were gathered from the following eleven analytes: PFBA, PFBS, PFHxA, PFHpA, PFHxS, PFOA, PFOS, PFNA, PFDA, PFUnA, and PFDoA. Depending on the analyte, a lower LOQ was established at 0.16 – 1.75ng/mL and an upper LOQ at 43.75 – 51.41 ng/mL. Based on the established linear calibration model an LOD in the range of 0.11 - 0.51 ng/mL was achieved. All eleven PFAS analytes showed an acceptable bias of ±20%. All analytes showed a between-run precision (%CV) in an acceptable range of ±20%. No matrix interferences were detected. The average recovery for SPE ranges from 77.64- 104.73% with recovery of 77.64% for PFBS, 83.89% for PFBA, and 95.64-104.73% for PFHxA, PFHpA, PFHxS, PFOA, PFOS, PFNA, PFDA, PFUnA, and PFDoA.
Utilizing the UCT WAX SPE column, good recovery for the PFAS compounds was demonstrated. Further, the extraction technique was efficient for high throughput analysis with the extraction time comparable to other traditional SPE methods. The total analytical run time of 11 minutes using the QSight®220 coupled with the UCT Selectra C18 100 x 2.1mm x 3μm column allowed for adequate re-equilibration and system washes to prevent carryover and contamination of these persistent pollutants with excellent chromatography. Having the ability to efficiently and accurately quantify PFAS compounds in biological matrices will allow for better understanding of prevalence, bioaccumulation in biological matrices, and will aid in understanding how these concentrations relate to various health outcomes.
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PFAS in recipient sediment of a military airportJohansson Blomér, Lovisa January 2017 (has links)
Per- and polyfluoroalkyl substances, PFASs, are highly fluorinated substances where the carbon chain is fully- or partly fluorinated. A functional group is coupled at the end of the carbon chain which gives PFASs their different properties. PFASs have been used in aqueous film forming foams (AFFFs) to decrease the surface tension of water and form a film on the fuel surfaces. AFFF is one of the main sources of PFASs pollution in the environment. A previous study has shown high PFASs concentrations in surface water in Lake Vänern. This study has analysed PFASs in sediment samples. The main detected PFASs was perfluorooctane sulfonate, PFOS, with concentrations below limit of detection to 51700 pg/g wet weight (ww). The compound detected in the highest concentration in Vissbäcken was PFOS at 7290 pg/g ww, this was followed by 6:2 fluorotelomersulfonate , 6:2FTS, at 516 pg/g ww. In outlet 4 (utlopp 4), PFOS had the highest concentration at 51800 pg/g ww, followed by perfluorohexane sulfonate, PFHxS, at 1790 pg/g ww. The only detected compound in the sediment cores was PFOS with approximately 100 pg/g ww. The high concentration of PFOS might be due to extensive use with subsequent release of firefighting foam in the area and degradation of other PFAS substances into PFOS. / Per-och polyfluoroalkylsubstanser, PFASs, är en grupp högfluorerade ämnen där kolkedjan är helt eller delvis fluorerad. En funktionell grupp kopplas i slutet av kolkedjan vilket ger PFASs dess olika egenskaper. PFAS har använts i vattenhaltiga filmbildande skum (AFFF) för att minska ytspänningen av vatten och bilda en film på bränsleytan. AFFF är en av huvudkällorna för PFAS-föroreningar i miljön. En tidigare studie har visat på höga koncentrationer av PFASs i ytvatten i Vänern. I denna studie har PFASs analyserats i sedimentprover. Den huvudsakliga detekterade PFAS var perfluoroktansulfonat, PFOS, med koncentrationer under detektionsgränsen och till 51700 pg /g våtvikt. Den högst detekterade föreningen i Vissbäcken var PFOS med 7290 pg/g våtvikt, detta följdes av 6:2 fluorotelomersulfonat, 6:2 FTS, med 516 pg/g våtvikt. Den högst detekterade föreningen i utlopp 4 var PFOS med 51800 pg/g våtvikt, följt av perfluorhexansulfonat, PFHxS, med 1790 pg /g våtvikt. Den enda detekterade föreningen i sedimentpropparna var PFOS med ungefär 100 pg/g våtvikt. Förekomsten av PFOS i sediment i sjön Vänern kan bero på omfattande användning med efterföljande utsläpp av brandbekämpningsskum i området och nedbrytning av andra PFAS-substanser till PFOS.
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Identification of Neurotoxic Targets of Diverse Chemical Classes of Dietary Neurotoxins/NeurotoxicantsRachel M Foguth (9343949) 16 December 2020 (has links)
<p>Neurological disorders are a
major public health concern due to prevalence, severity of symptoms, and impact
on caregivers and economic losses. While genetic susceptibility likely has a
role in most cases, exposure to toxicants can lead to neurotoxicity, including
potentially developmental origins of adult disease or increased risk of disease
onset. These exposures are not necessarily large, acute exposures, but could
accumulate, with a chronic low-dose exposure, causing toxicity. This research
focuses on the potential neurotoxicity of two classes of dietary toxins/toxicants,
heterocyclic aromatic amines (HAAs) and per- and polyfluoroalkyl substances
(PFAS). HAAs, such as PhIP, harmane, and harmine, are formed in charred or
overcooked meat, coffee, tobacco, and other foods. PFAS are largely used in
making household materials, but are found in small amounts in eggs and dairy
products and largely in contaminated water. While these two classes are diverse
in terms of structure, common neurotoxic targets and mechanisms often exist. Therefore,
we tested the effects of these chemicals on cell viability and neurotoxicity. In
the first aim, we aimed to elucidate the mechanism of toxicity of harmane and
harmine, focusing on their ability to cause mitochondrial dysfunction. The
second aim was to determine the effects of either harmane or PhIP on the nigrostriatal
motor systems and motor function of rats and mice, respectively. The third aim
determined the effects of PFAS on neurodevelopment of Northern leopard frogs,
focusing on changes in neurotransmitter levels and accumulation in the brain. Harmane
did not cause motor dysfunction, but potentially affected the nigro-striatal
motor system in an age- or sex-dependent manner. PhIP had differential effects
on dopamine levels over time and caused motor dysfunction after subchronic
exposure in mice. Perfluorooctane sulfonate (PFOS) accumulated in the brains of
frogs and PFAS caused changes in neurotransmitter levels that were dose- and
time-dependent. Overall, this research shows that toxins/toxicants humans are
exposed to over their whole lives through their diet and contaminated water can
cause neurotoxicity, potentially leading to or increasing risk of disease
states. </p>
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Evaluation of selected parameters of Total Oxidisable Precursor Assay on per- and polyfluoroalkyl substancesFrancois, Sofia January 2021 (has links)
Per- and polyfluoroalkyl substances (PFASs) are man-made fluorinated compounds that havebeen detected in humans, the environment, and wildlife. The strong C-F bonds contribute tothe high thermal stability of some PFASs and make them extremely resistant to degradationunder normal environmental conditions. The commonly studied classes of PFASs areperfluoroalkyl carboxylic acids and perfluoroalkyl sulfonic acids. Though the phase-out ofperfluorooctane sulfonic acid and perfluorooctanoic acid for some time, they were the mostfrequent compounds measured and detected in biota.In this study, the total oxidisable precursor (TOP) assay, which is a method used to indirectlymeasure and estimate PFAS precursors, was evaluated. Different parameters were studied tounderstand their effects on oxidation of precursor compounds following TOP assay method(e.g., oxidation rate, pH of the oxidation solution and different washing steps during solidphaseextraction)The results from this experiment showed that the target precursors were oxidised and part ofthe proportion of the compounds formed ranged from 37 to 100% (molar ratio). Whenperforming TOP assay, it was shown that some precursors oxidised before 0.5 h while otherprecursors were oxidised after 4 hours. However, it was still unknown what products wereformed when some precursors were oxidised e.g., 7:3 fluorotelomer carboxylic acid (7:3-FTCA) and 10:2 fluorotelomer unsaturated carboxylic acid (10:2- FTUCA) because of animbalance of precursors to degradation products (molar to molar ratio).When the washing steps for solid-phase extraction were evaluated for potential losses ofprecursors, it could be seen that the ammonium acetate and the 20% methanol in Milli-Q waterled to the loss of some precursors. These results showed precautions were needed wheninterpreting the results using TOP assay.
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