Dissertations / Theses on the topic 'Perfluoroaryl'

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1

Özer, Mehmet Sabih. "3-perfluoroalkyl-[Beta]-alanines, lipo-perfluoroalkyl-peptidoamines, molécules amphiphiles complexantes." Nancy 1, 1999. http://www.theses.fr/1999NAN10129.

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La conception et la méthodologie de synthèse de molécules tensioactives perfluorées, ainsi que la caractérisation générale et particulière de leurs propriétés sont les objectifs que nous nous sommes fixés. De nombreuses études portent sur des applications médicales, impliquant des fluorocarbures et/ou des composés hautement fluorés. La chimie de ces dérivés organofluorés a, en effet, un impact important dans le domaine de la conception et de la synthèse de molécules à activité biologique. Ainsi, associer des structures polaires de type peptidoamines, telles que la carcinine et la carnosine, à des chaînes perfluorées à propriétés émulsifiantes, contribue au développement d'une recherche innovante dans le domaine biochimique et/ou thérapeutique. La caractéristique la plus fameuse des fluorocarbures est leur grande capacité à dissoudre l'oxygène et d'autres gaz, dans des proportions importantes. Mais pour une utilisation en biologie, ils doivent nécessairement être sous forme d'émulsions. [. . . ]
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2

Mei, Hua. "Perfluoroalkyl (aryl) sulfonimide zwitterions." Connect to this title online, 2006. http://etd.lib.clemson.edu/documents/1175185494/.

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3

Colomer, Vidal Pere. "Distribution of perfluoroalkyl substances in the environment." Doctoral thesis, Universitat de Barcelona, 2021. http://hdl.handle.net/10803/670952.

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Perfluoroalkyl substances (PFASs) are a large group of man-made chemicals that are widely used throughout society and found in the environment. These compounds are characterized by perfluorinated carbon chains of varying lengths with hydrophobic properties and containing an external polar and hydrophilic head. The difference between perfluoroalkyl sulfonates (PFSAs) and perfluoroalkyl carboxylates (PFCAs) are found on the polar head of the chemicals. In general, the characteristics of PFASs are based on the length of the perfluorinated carbon chain that they contain. As the number of perfluorinated carbons increases in the molecule, the water solubility decreases and the better the surfactant properties, but will be more toxic for the environment due to their bioaccumulation in the organisms. In recent years, the interest in PFASs has been growing due to their presence in humans and in wildlife species even from remote locations, which suggests a widespread global distribution of these pollutants. The highest concentration of PFASs has typically been documented in areas with direct industrial emissions. The main purpose of this Doctoral Thesis is to study the distribution and behavior of PFASs in different environmental compartments and to elucidate the interactions among them. In the first study of this Thesis, seventeen PFASs have been analyzed in the water-sediment-plant system along the Dongzhulong and Xiaoqing Rivers in China. The study area is affected by a fluoropolymer facility that belongs to the Dongyue group and is currently one of the major facilities of polytetrafluorethylene production in China. Some studies indicate a presence of PFASs in sediments and soils and these can be a source of pollution for wildlife, and humans. The second study is aimed to evaluate the environmental occurrence of PFASs in sediments, soils, and wildlife in the marine environment surrounding the Chafarinas Islands (South Spain) and the impact on gulls. The third study that composes this Thesis is aimed to evaluate the occurrence and 10-year temporal trend of seventeen PFAS in eggs of two gull species (Larus michahellis and Larus audouinii). These species are used as bioindicators of environmental pollution of Spain. The results of this Thesis show that the fate of the PFASs in the environment is explained by their physicochemical properties and the characteristics of the different study matrices. In freshwater systems, high amounts of PFASs in water and sediments close to the industrial discharge were detected, and concentrations decreased along the river due to dilution. In the water-sediment system, the results suggest that long-chain PFASs accumulated in sediment whereas short-chain PFASs remained in water all along the river. When including plants in the system, PFASs were taken up by plants and translocated in the different plant compartments, and the uptake mechanisms differed among plant species. Floating species show a higher concentration among plants because easily translocate long-chian PFASs direct from the water. Rooted species must compete with the sediment for PFASs uptake. Moreover, long-chain PFASs remain accumulated in the root compartment because of protein affinity while short-chain PFASs are more mobile and can be translocated to shoots. In the marine environment of the Chafarinas Islands, low levels of PFASs detected in soils, sediments, fish, and mussels reflected that the area is not directly impacted by PFASs. In this Thesis we also have estimated the bioaccumulation potential of PFASs, using gulls. We have estimated the intake based on fish-diet in gulls from Chafarinas. We observe that the release of PFOS to the egg is 4.5% of the intake and we provide the basis for using gull eggs as biomonitors. In a final study of this Thesis, we evaluated the presence of PFASs in four main gull colonies in Spain. When comparing gull colonies, eggs from the Ebro Delta and Medes Islands, both located in the North-Eastern Mediterranean Sea, had a similar distribution of PFASs, while in Chafarinas and Atlantic Islands these PFASs were present at lower concentration levels and variability. In the Ebro Delta colonies, concentrations in eggs from L. audouinni were significantly higher than those found in L. michahellis, suggesting that fish diet influences PFAS bioaccumulation. Overall, ∑PFAS decreased in the 10-year study period but for individual compounds, trends were colony-species dependant. This thesis permits to increase the knowledge about the processes that rule the behavior of PFASs in water, sediment, soil, and biota. Also, this thesis demonstrates the advantage of performing systematic monitoring schemes to determine the presence and fate of PFASs in the environment.
El objetivo principal de esta Tesis Doctoral es estudiar la distribución y el comportamiento de las sustancias perfluoroalquiladas (PFASs) en diferentes compartimentos ambientales. En esta tesis se analizan diecisiete PFASs en el sistema de plantas de agua-sedimento a lo largo de los ríos Dongzhulong y Xiaoqing, en sedimentos, suelos y fauna de las Islas Chafarinas (Sur de España), y para finalizar se evalúan las tendencias temporales durante 10 años en huevos de dos especies de gaviotas consideradas bioindicadores de contaminación. Los resultados de esta tesis muestran que la distribución de las PFASs en el medio ambiente se define por sus propiedades fisicoquímicas y las características de las diferentes matrices de estudio. En el sistema agua-sedimento, los resultados sugieren que la distribución de las PFASs depende de la longitud de la cadena. Las plantas absorben PFASs y los transfieren a diferentes compartimentos de las plantas. En el ambiente marino de las Islas Chafarinas, bajos niveles de PFASs se detectaron en suelos, sedimentos, peces y mejillones reflejando el poco impacto de estas sustancias en esa área. También se estimó el potencial de bioacumulación de las PFASs en gaviotas y se evaluó su presencia en huevos de diferentes colonias. Los huevos del delta del Ebro y de las islas Medas, ambos ubicados en el Mediterráneo nororiental, tenían una distribución de PFASs similar, mientras que en Chafarinas e Islas Atlánticas tienen a niveles de concentración muy bajos. En las colonias del Delta del Ebro, las concentraciones en huevos de L. audouinni fueron significativamente más altas que las encontradas en L. michahellis debido a diferencias en la dieta. En general, la concentración ∑PFASs disminuyó en el período de estudio, pero para los compuestos individuales las tendencias dependían de las colonias y especies.
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4

Pooput, Chaya. "Syntheses and studies of perfluoroalkyl substituted compounds." [Gainesville, Fla.] : University of Florida, 2005. http://purl.fcla.edu/fcla/etd/UFE0011625.

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5

Bao, Xujin. "Studies of liquid crystals containing perfluoroalkyl chains." Thesis, Northumbria University, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.245204.

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6

Manzano, Salgado Cyntia Beatriz 1987. "Prenatal exposure to perfluoroalkyl substances and child health." Doctoral thesis, Universitat Pompeu Fabra, 2017. http://hdl.handle.net/10803/585944.

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Perfluoroalkyl substances (PFAS), such as perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA), are synthetic chemicals commonly used in industrial and commercial products including consumer care products, fire-fighting foams, ski wax, and oil- and water-repellents for leather, paper, and textiles. Prenatal PFAS exposure may modulate fetal growth, fat accumulation, metabolic function, and immune response yet evidence coming from birth cohort studies is limited. In this thesis we first evaluated the transfer of PFAS from mother to fetus and the determinants of maternal PFAS exposure during pregnancy. This led us to the main objective of this thesis, to evaluate the association between prenatal exposure to PFAS and child health outcomes, specifically: fetal growth and preterm birth, obesity and cardiometabolic risk, and immune and respiratory health in early and mid-childhood. Data from the “Infancia y Medioambiente” (INMA) population-based Spanish birth cohort was used. The results from the present thesis indicate that PFOA can cross the placental barrier more efficiently than other PFAS, and that mothers were ubiquitously exposed to PFOS and PFOA during the years 2003-2008. We found little evidence for an association between prenatal PFAS exposure and child health outcomes (i.e. fetal growth and preterm birth, obesity and cardiometabolic risk, and immune and respiratory health). Prospective studies with follow-ups beyond mid-childhood are recommended.
Els compostos perfluorats (PFAS per la seva abreviació en anglès), com l'àcid perfluorooctanosulfònic (PFOS) i l'àcid perfluorooctanoic (PFOA), són productes químics sintètics utilitzats habitualment en productes industrials i comercials, per exemple escumes antiincendis, cera d'esquí, i repel·lents d'oli i aigua per a cuir i tèxtils. Durant les primeres etapes de la vida, l'exposició a PFAS pot influenciar el creixement fetal, l'acumulació de greix i la resposta immune però hi ha poca informació provinent d'estudis de cohort de naixements. En aquesta tesi primer es va avaluar la transferència de PFAS de la mare al fetus i els determinants de l'exposició materna durant l'embaràs. Això ens va conduir a l'objectiu principal d'aquesta tesi, que era avaluar l'associació entre l'exposició prenatal a PFAS i la salut infantil, específicament: el creixement fetal i el part prematur, l'obesitat i el risc cardiometabòlic, i la salut immunològica i respiratòria durant l'infància. Es van utilitzar dades de la cohort poblacional de naixements Infància i Medi Ambient (INMA) a Espanya. Els resultats de la present tesi indiquen que PFOA travessa la placenta més eficientment que els altres PFAS i que les mares van estar exposades a PFOS i PFOA de manera ubiqua durant els anys 2003-2008. En general, l'exposició prenatal a PFAS estava poc associada amb els resultats de salut infantil avaluats. Es recomanen estudis prospectius amb un seguiment posterior a l'infància.
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7

Leclerc, Matthew. "Advances in the Fluorine Chemistry of Transition Metals and N-Heterocyclic Carbenes: Understanding Perfluoroalkyl and Fluoroalkene Reactivity." Thesis, Université d'Ottawa / University of Ottawa, 2017. http://hdl.handle.net/10393/36218.

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The importance of fluorine in a wide array of different areas within chemistry and biochemistry has been demonstrated time and time again. Fluorine-containing products range from essential substituents in pharmaceuticals and relatively long-lived tracers for PET imagining, to fluoropolymers with outstanding properties, to essential components in most of the strongest acids available to chemists today. Fluorine’s extreme electronegativity makes it a truly unique element, but its acute toxicity in its elemental F2 form makes it difficult to handle, prompting researchers to explore different options for incorporating this important element into a variety of different molecular scaffolds. Due to the remarkable thermodynamic and kinetic stabilities of C-F bonds, methods for forming and breaking these cleanly, and under relatively mild conditions, are in high demand. Fortunately, transition metals have greatly aided in this process. However, fluoroorganometallic chemistry is much less developed than transition metal chemistry involving hydrocarbons, and certainly less understood. One of the primary reasons for this relative dearth of fluoroorganometallic complexes is the difficulty associated with their synthesis. In this work, important steps towards perfluoroalkyl chain-growth within the coordination sphere of a transition metal will be presented, stemming in part from the synthesis and characterization of novel cobalt fluoride and bis(perfluoroalkyl) complexes. As important electrophiles, fluoroalkenes have primarily been used as monomers for the formation of important fluoropolymers. However, their direct reactivity with organics remains rare and is usually difficult to control, with limited substrate scopes. Herein, the formation of stable N-heterocyclic fluoroalkene adducts as versatile synthons for the incorporation of fluoroalkene fragments into various chemical environments will be introduced. By forming these adducts, the inconvenience of manipulating fluorinated gases in further reactions can be avoided, and the N-heterocyclic fragment is shown to aid in directing substitutions involving polyfluoroalkenyl imidazolium salts and organic nucleophiles to form a variety of C-E (E = C, N, O, S) and C-M bonds (M = Mn, Mo). The ease with which C-F bonds are manipulated in these systems is quite remarkable, as the substitution reactions occur cleanly and efficiently at room temperature, to form a variety of new bonds without the need for a transition metal. By expanding on the fundamental reactivity between N-heterocyclic carbenes and fluoroalkenes, attempts were made to correlate the observed reactivity with certain electronic and steric parameters unique to the utilized carbenes. Although a correlation has not yet been established, the effects of atypical steric constraints in a cyclic (alkyl)(amino)carbene were demonstrated, wherein the initial point of attack by the carbene on the fluoroalkene was modified. It is hoped that this work will eventually lead to new roles for organocatalysts in fluoroalkene transformations.
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8

Llorca-Casamayor, Marta. "Analysis of perfluoroalkyl substances in food and evironmental matrices." Doctoral thesis, Universitat de Barcelona, 2012. http://hdl.handle.net/10803/97204.

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Per- and poly- fluoroalkyl substances (PFASs) are a group of manmade substances synthesised for more than 60 years. Due to their specific properties, PFASs have been widely used for industrial applications including: electronics, textiles, food packaging, flame retardant formulae and laboratory tools, among others. However, it was during the last fifteen years ago that interest for this group of compounds as environmental pollutants was initiated. Due to their high release levels into the environment, stability and accumulation, PFASs have been found ubiquitous in the environment and in biota. In this context, the main goal of this doctoral PhD thesis was the study of the occurrence, fate and behaviour of a wide range of PFASs in the environment, in food and, finally, in some human matrices. In addition, the physicochemical properties studies and the aerobic biodegradation experiments of 3 perfluoroalkyl phosphonic acids were also evaluated. Therefore, the first specific objective was the development of different analytical methods to study a wide range of PFASs in selected matrices. The analytical methods have been based on the use of on-line chromatography and off-line extraction, followed by liquid chromatography coupled to tandem mass spectrometry. These methods have been employed to assess the presence of PFASs in different type of waters from different steps along the water cycle, and also in fish and other food commodities. And finally, the PFAS accumulation in human samples was studied in cord blood and breast milk. This work is divided into six chapters. The first chapter is the general introduction and the objectives of this PhD Thesis. In the introduction, different aspects are revised, such as synthesis and global production, environmental fate and occurrence, human accumulation, toxicology, regulations and future trends. Chapters 2, 3, 4 and 5 present the experimental work undertaken during this research. Each chapter has been divided into a specific introduction, results (presented through the corresponding publications) and discussion. Part of the results contained in Chapters 2 and 5 correspond to the experimental work carried out in the laboratory of Prof. Dr. Thomas P. Knepper (Hochschule Fresenius, Idstein, Germany) during a four month research internship, a part of the European Doctoral Programme. Chapter 6 contains the general conclusions. Finally, a small summary in Catalan is presented. The cited literature and indexes for tables and figures can be found at the end of this work, as well as the list of publications produced along the duration of the pre-doctoral studies, but which are not presented in this thesis. The distribution of the publications included in this Thesis is the following: Chapter 2: Environmental occurrence Publication 1: “Analysis of perfluoroalkyl substances in waters from Germany and Spain.” Llorca, M., Farré, M., Picó, Y., Müller, J., Knepper, T. P. and Barceló, D. (2012). Science of The Total Environment, 431(0): 139-150. Publication 2: “Analysis of perfluorinated compounds in sewage sludge by pressurized solvent extraction followed by liquid chromatography–mass spectrometry.” Llorca, M; Farré, M; Picó, Y; Barceló,D; (2011). Journal of Chromatography A, 1218 (30) 4840-4846. Publication 3: “Fate of a broad spectrum of perfluorinated compounds in soils and biota from Tierra del Fuego and Antarctica.” Llorca, M., Farré, M., Tavano, M. S., Alonso, B., Koremblit, G. and Barceló, D. (2012). Environmental Pollution 163(0): 158-166. Chapter 3: PFASs in food Publication 4: “Development and validation of a pressurized liquid extraction liquid chromatography-tandem mass spectrometry method for perfluorinated compounds determination in fish.” Llorca, M., Farré, M., Picó, Y., and Barceló, D. (2009). Journal of Chromatography A 1216(43): 7195-7204. Publication 5: “Study of the performance of three LC-MS/MS platforms for analysis of perfluorinated compounds.” Llorca, M., Farré, M., Picó, Y., and Barceló, D. (2010) Analytical and Bioanalytical Chemistry 398(3): 1145-1159. Publication 6: “Infant exposure of perfluorinated compounds: Levels in breast milk and commercial baby food.” Llorca, M., Farré, M., Picó, Y., Teijón, M. L., Álvarez, J. G. and Barceló, D. (2010). Environment International 36(6): 584-592. Chapter 4: PFASs accumulation in humans Publication 7: “Analysis of perfluoroalkyl substances in cord blood by turbulent flow chromatography coupled to tandem mass spectrometry.” Llorca, M., Pérez, F., Farré, M., Agramunt, S., Kogevinas, M. and Barceló, D. (2012). Science of The Total Environment 433(0): 151-160.
Les substàncies per- i poli- fluorades (PFASs) són d’origen antropogènic. Aquest ampli grup de compostos s’ha sintetitzat durant més de 60 anys. Degut a les seves propietats específiques s’utilitzen encara en l’actualitat en diferents aplicacions industrials tals com: electrònica, recobriments tèxtils, embolcall d’aliments, escumes ignífugues i material de laboratori entre d’altres. No obstant, no ha estat fins els últims 15 anys quan a aquests compostos se’ls ha començat a considerar contaminants ambientals. Degut als nivells que es troben en el medi ambient, l’estabilitat i l’acumulació que presenten, aquests anàlits tenen una distribució global en el medi i en biota. En aquest context, el principal objectiu d’aquesta tesi doctoral ha estat l’estudi de la presència, destí i comportament d’un ampli grup de PFASs (13 àcids prfluoroalquílics, 4 perfluorosulfats, 1 perfluorosulfonamida i 3 àcids perfluorofosfònics) en el medi ambient, aliments i, finalment, en algunes matrius humanes. En paral•lel a l’estudi dels esmentats treballs, s’han realitzat en experiments per determinar algunes de les propietats fisicoquímiques i la possible biodegradació aeròbica de 3 àcids perfluorofosfònics. Per aquest motiu, el primer objectiu específic ha esta el desenvolupament de diferents mètodes analítics per a l’estudi d’aquests anàlits en les matrius seleccionades. Els mètodes analítics desenvolupats han inclòs tant mètodes d’extracció fora de línia com de cromatografia en línia, seguit d’una separació per cromatografia líquida acoblada en tàndem a l’espectrometria de masses. Aquests mètodes han estat utilitzats per al posterior estudi de la presència de PFASs en diferents mostres d’aigua provinents de tot el cicle de l’aigua així com peix i altres aliments. Finalment, l’acumulació de PFASs en humans s’ha estudiat a partir de l’anàlisi de mostres de sang de cordó umbilical i llet materna.
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Filipovic, Marko. "Mass balance of perfluoroalkyl acids in the Baltic Sea." Licentiate thesis, Stockholms universitet, Institutionen för tillämpad miljövetenskap (ITM), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-88779.

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Perfluoroalkyl acids (PFAAs) are man-made chemicals. Their unique properties make them beneficial for a wide range of industrial and consumer applications, such as constituents in fire fighting foams, hydraulic oils and food packaging materials.PFAAs have shown to be highly persistent in the environment, and the toxicological potential of long chain PFAA homologues is of a concern. International regulation and voluntary actions by the industry have been implemented and led to reduced primary emissions of PFAAs to the environment. However, the concentrations of some PFAAs in e.g. birds from the Baltic Sea are still very high and of ecotoxicological concern. Measures to reduce the PFAA contamination require an understanding of the sources and how the PFAAs are being transported in the environment.In this licentiate thesis a mass balance was assembled for perfluorohexanoic acid (PFHxA), perfluorooctanoic acid (PFOA), perfluorodecanoic acid (PFDA) and perfluorooctane sulfonic acid (PFOS) in the Baltic Sea. A one-box model was used including the input pathways river inflow, atmospheric deposition, wastewater discharges and inflow from the North Sea via the Danish Straits, while the loss processes considered were sediment burial, transformation of the chemicals and outflow to the North Sea via the Danish Straits. Additionally, the inventories of the four target PFAAs in the Baltic Sea were estimated. Both chemical fluxes and inventories were estimated using recently published monitoring data (2005-2010).In order to obtain a detailed perspective on the current knowledge regarding PFAAs in the Baltic Sea, challenges and uncertainties in data selection were discussed for the most dominant input pathways. This included WWTP emissions and calculation of emission factors (EFs), atmospheric deposition and riverine inflow.River inflow and atmospheric deposition were the dominant inputs, while wastewater treatment plant (WWTP) effluents made a minor contribution. The input to the Baltic Sea exceeded the output for all 4 PFAAs, suggesting that inputs were higher during 2005-2010 than during the previous 20 years despite efforts to reduce emissions of PFAAs. Comparing the difference between PFAA input and output with the PFAA inventory, the doubling time for the concentration in the Baltic Sea was estimated to be 8-94 yr for PFHxA, 12-16 yr for PFOA, 3-5 yr for PFDA and 4 yr for PFOS. The surplus of the input can be an effect of retention and delayed release of PFAAs from atmospheric deposition in the soils and groundwater of the watershed.The licentiate thesis contributes to a holistic understanding of the major input and output pathways and inventories of PFAAs in the Baltic Sea. Furthermore, it points out current knowledge gaps in our understanding of sources and fate of PFAAs in the aquatic environment.

At the time of the defence the following papers were unpublished and had a status as follows: Paper 1: Manuscript

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Spector, Lovisa. "Supramolecular solvents for the extraction of perfluoroalkyl substances in water." Thesis, Örebro universitet, Institutionen för naturvetenskap och teknik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-66788.

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The aim of this project was to compare two methods for the extraction of perfluoroalkyl substances (PFASs) in water samples. The methods compared were solid phase extraction (SPE) and supramolecular solvents (SUPRAS). Solid phase extraction is a sample preparation process where the desired compound passes through a solid phase and the method uses the affinity for the compound of interest to retain it in the solid phase while the undesired compounds pass through. Supramolecular solvents are an alternative approach for extraction of contaminants, for example PFASs. Supramolecular solvents are liquids that generates from compounds known as amphiphiles. The desired compound is extracted by binding with ionic bond, hydrogen bond, dipole-dipole bond, or other depending on the desired compound. A comparison of methods was evaluated based on method detection limits (MDL), recovery, matrix effects and repeatability. The recoveries for SPE (n=11) were best for short-chain PFASs with recoveries between 81-128%. The recoveries decreased with increasing carbon chain length, probably due to the sorption of analytes to the wall of the container or the reservoir that were not washed thoroughly. The matrix (e.g. surface water) for the solid phase extracted samples were concluded to slightly suppress the signal of most PFASs. The repeatability for the SPE samples had values between 8-59%, with an average of 18%. The recoveries of PFASs (n=4) when using SUPRAS for the extraction of PFASs from water samples were generally lower than those of the SPE method. Especially the short-chain PFASs have poor recoveries in SUPRAS extraction. For longer carbon chain PFASs the recovery for the samples extracted with SUPRAS showed better values (58-135%) but with decreasing chain length the recoveries also decreased. For SUPRAS method to be a feasible option, extraction efficiency of 50-120% would be needed. The matrix effects indicated that the matrix of the SUPRAS extracted samples enhanced the signal of most PFASs. The repeatability could not be calculated for the environmental (SUPRAS Method 1) SUPRAS samples since no replicate blanks were extracted. Spiking experiments on Milli-Q water was performed and had RSD values between 22-85% with a mean value of 39 %. This preliminary test of using SUPRAS as extraction method of PFASs in water need to be further developed. At present SUPRAS is not as efficient for the extraction of PFASs from water as using solid phase extraction. Screening of solvents and possibly salting out need to be tested to increase the efficiency of the extracted compounds.
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Thorpe, Adrian A. "Alkyl and perfluoroalkyl siloxanes : synthesis, surface energies and antifouling performance." Thesis, University of Portsmouth, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.322715.

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Johnstone, James E. "Preparation and characterisation of novel fluorinated surfaces." Thesis, University of York, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.286153.

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13

Sundström, Maria. "Radiosynthesis of Perfluoroalkyl Substances : Chemical analysis, uptake, distribution, and partitioning studies." Doctoral thesis, Stockholms universitet, Institutionen för material- och miljökemi (MMK), 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-81061.

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Perfluoroalkyl substances (PFASs) are widely utilized manmade chemicals. Their properties have made them highly appreciated in a variety of industrial and consumer product applications, including fire-fighting foams, hydraulic fluids, as well as in cookware and food contact papers. However, some of the PFASs are highly persistent in the environment and their toxicological profiles are of concern. Voluntary and regulatory efforts have been taken to reduce the environmental levels of PFASs. These actions have resulted in a reduction of PFASs in human milk from Stockholm as presented in this thesis. The radiosyntheses of 35S-PFOS, 35S-PFBS, and 14C-PFOA presented herein were applied for distribution studies in mice but also for solubility and adhesion experiments of common laboratory solvents and buffers. The radiosynthesis employed reactive Grignard reagents, perfluoroalkyliodides, and 35S-sulfur dioxide or 14C-carbon dioxide. The distribution studies were performed with 35S-PFOS on both pregnant mice and their offspring as well as on male mice. The mice were subjected to whole-body autoradiography and the tissues were analyzed by liquid scintillation counting. Liver and lungs were the target organs for 35S-PFOS in the dams. The fetuses and pups had remarkable high levels of 35S-PFOS in their lungs as well as in the brain. The male mice were given a high dose and a more environmental relevant dose of 35S-PFOS. PFOS was transferred from the blood to the tissues as the dose increased. In another study the distribution pattern of the shorter homologue PFBS was compared to PFOS. 35S-PFBS was utilized and demonstrated a 5-40 fold lower tissue levels in comparison to PFOS. The pharmacokinetic parameters determined for PFHxS in mice, rats, and monkeys will provide valuable insight in establishing a proper risk assessment for this compound. The study confirms the common species differences in serum elimination half-life that are associated with PFASs.

At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 6: Manuscript.

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Lövgren, Eleonore. "Perfluoroalkyl substances in the groundwater of Stockholm, the role of subsurface reactions." Thesis, KTH, Mark- och vattenteknik (flyttat 20130630), 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-171802.

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Perfluoroalkyl acids (PFASs) are toxic pollutants ubiquitously found in the ecosystem. Recent investigations have focused on describing their environmental behavior and spreading. This includes transportation by water, where groundwater can continue to spread the contaminants a long time after the use has ended. This thesis surveys the existing literature on the reactions in soil that decides the presence and composition of PFASs in groundwater. A chemical groundwater investigation was recently done by Stockholm’s Environmental and Health Administration. The thesis presents a quantitative analysis of the PFASs’ content in Stockholm’s groundwater to verify if it conforms to the literature. A statistical analysis of the ratio between perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) is included to test if the PFAS composition in groundwater is influenced by soil reactions. The literature states that due to the high water solubility, low volatility and moderate adsorption, PFASs are likely to be encountered in groundwater. The adsorption depends on both PFASs’ and soil’s properties. The quantitative analysis confirms the influence of the PFASs’ properties in Stockholm’s groundwater, where both more short-chained PFASs and carboxylates are present. However, the analysis could not confirm the influence of the soil properties in adsorption at normal environmental conditions. The statistical analysis shows that the ratio of PFOS to PFOA is increased in groundwater in comparison to stormwater (p < 0.15). The increase cannot be explained by the hypothesis that the adsorption of PFAS governs this behavior, since PFOS is a sulfonate and longer than PFOA. An explanation is found in the degradation of precursors, which seems to contribute to PFOS concentrations in groundwater. This shows the important contribution of degradation of precursors to PFOS concentrations and motivates further investigations on the matter.
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15

Fletcher, James R. "Studies of novel perfluoroalkyl derivatives of azobenzene in solution and on surfaces." Thesis, Loughborough University, 2011. https://dspace.lboro.ac.uk/2134/8416.

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Azobenzene based photochromics have been studied widely since the development of the first azo dye, Mauvine, by Perkin in 1856. Azo based dyes have been widely used in industry for over a century. The desire to study them arose from their ease of synthesis and the wide availability of colours which can be tuned by manipulation of the chromophores on the azo molecule itself. The ability of azobenzene to photoisomerise between trans and cis states is widely known. The change in dipole moment affords the ability to fine-tune surfaces via photoisomerisation of the azo molecule. The objective of this investigation was to alter the surface properties of a variety of substrates via the photoisomerisation reaction of several perfluoroalkyl derived azobenzene compounds. These compounds are novel and are based on the idea of the fluoroalkyl chain creating a superhydrophobic surface, similar to Teflon, which would change surface energy upon isomerisation of the azobenzene molecule to give a more hydrophilic surface. This would ultimately then be utilised to coat a fabric surface to provide a photosensitive coating. The compounds used in this work (Admat 1 and 2 and Cfam derivatives) were synthesised in order for their photochemistry in solution and on surfaces to be investigated. The studies began with the photoisomerisation investigations in solution and the calculation of the rate constant and finally the activation energies of these compounds in a variety of common solvents. Interesting results were observed in polar protic solvents which were investigated further. The discovery that aggregation occurred in polar protic solvents due to solubility issues, which in turn led to a fast rate constant was a key finding of the solution work. The surface studies began with the investigation of cellulose as a substrate due to the structural similarity it has with cotton. The azo compounds were derivatised using cyanuric chloride to afford a triazinyl group which was able to attach to the surface of the cellulose via the hydroxyl groups on the surface.
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Oleksik, Laurence. "Methodology for the synthesis of 4 or 5-substituted-3-perfluoroalkyl pyrazoles." Thesis, University of Leicester, 2004. http://hdl.handle.net/2381/30087.

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Initially the perfluoroacylation of a range of commercially available vinyl ethers and conversion of the resulting perfluoroacylated enol ethers to 1-H-pyrazoles via reaction with hydrazine is reported. The selective synthesis of a range of alpha-aryl vinyl ethers using Heck chemistry is then reported. Subsequent perfluoroacylations of the vinyl ethers followed by reaction of the resulting perfluoroacyl enol ethers with hydrazine affords a range of 5-aryl-3-perfluoroalkyl pyrazoles in good yields.;Alternative methodology for the synthesis of 5-aryl-3-perfluoroalkyl pyrazoles is then described in which resin bound esters are converted to vinyl ethers
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17

Baabish, Abeer. "Global Priority Perfluoroalkyl Substances in Surface Waters:Establishing Baseline Levels on Regional Basis." Thesis, Örebro universitet, Institutionen för naturvetenskap och teknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-75690.

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Perfluorooctane sulfonic acid (PFOS) has been regulated under Stockholm Convention in 2009, perfluorooctanoic acid (PFOA) was listed in 2019. Perfluorohexane sulfonic acid (PFHxS) is under review and could be included in 2021. There are still permitted uses of these three chemicals, but it is expected that the production and application will decrease as a result of the international regulation and the environmental concentrations of PFOS, PFOA and PFHxS are expected to decline. However, without a reference point, it is difficult to judge if the levels are decreasing or not. Therefore, baseline levels of PFOS, PFOA and PFHxS in one of United Nations Environment Programme (UNEP) core matrices, surface water, were established with the support of samples collected from Africa (n=34), Asia (n=11), Group of Latin America and Caribbean (GRULAC) (n=35) and Pacific Islands (n=25) under a period of two years. The baseline levels were set as the median concentration (ng/L) in each region (interquartile range) based on a variance test (Kruskal-Wallis) and descriptive statistical testing. Baseline levels for ΣPFOS, PFOA and PFHxS including all countries in Africa (n=6) was set at 0.38 (0.18 – 0.54) ng/L, 0.26 (0.13 – 0.80) ng/L and 0.042 (0.02 - 0.09) ng/L respectively, and excluding Kenya and Tunisia (n=4) at 0.22 (0.10 – 0.38) ng/L for ΣPFOS , 0.18 (0.10 – 0.25) ng/L for PFOA and 0.031 (0.02 – 0.04) ng/L for PFHxS. In Pacific Islands the baseline levels for ΣPFOS, PFOA and PFHxS were established at 0.15 (0.04 – 1.24) ng/L, 0.046 (0.03 – 0.11) ng/L and 0.055 (0.01 – 0.63) ng/L including all countries (n=7), and 0.053 (0.03 – 0.15) ng/L, 0.033 (0.03 – 0.04) ng/L and 0.012 (0.01 – 0.05) ng/L excluding Vanuatu and Kiribati (n=5). In Asia and Group of Latin America samples were in similar concentrations range within the region, so baseline levels for ΣPFOS, PFOA and PFHxS in Asia were set at 0.048 (0.04 - 0.12) ng/L, 0.11 (0.07 – 0.19) ng/L and 0.018 (0.01-0.03) ng/L, and in GRULAC at 1.31(0.39 – 1.88) ng/L, 0.50 (0.28 – 0.71) ng/L and 0.14 (0.06 – 0.44) ng/L for the three priority PFASs respectively. The importance of the three PFASs in relation to other measured Σ73 PFASs were assessed in selected samples (n=12) including six samples from Sweden. The results showed a contribution of 10% to 48% of the sum of the three priority PFASs to all 27 detected PFASs.It is not clear whether a total of 73 PFASs is enough to explain the environmental contamination of PFASs and therefore the extractable organofluorine (EOF) was measured in selected samples (n=12). Due to the high EOF levels in procedural blanks, only two out of twelve samples were used to assess the contribution of detected PFASs to EOF. The contribution of 27 detected PFASs to EOF were 3% for Vanuatu and 5% for Sweden (Svartån). The contribution of the sum of the three PFASs to EOF accounted for 1.1% for Vanuatu and 1.4% for Svartån. Nevertheless, within the organofluorine fraction, a major percentage 95% to 97% of fluorine remains unknown in water samples, suggesting the occurrence of other organofluorine substances. At the same time, some newly identified PFAS (novel PFASs) that are known to replace PFOS and PFOA in different applications were detected in surface water samples collected from Sweden (n=6) and from developing countries under UNEP/GMP2 project (n=6). Perfluoroethylcyclohexane sulfonate (PFECHS) was detected in four samples in concentrations ranging between 0.03 and 0.14 ng/L. Perfluoro-2-propoxypropanoic acid (HFPO-DA) was detected in three samples in the concentration range 0.03-0.06 ng/L.
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18

Tyson, J. Cameron. "Monolayer and host-guest chemistry of azocalix[n]arenes ; II Perfluoroalkyl-substituted polythiophenes." Diss., Georgia Institute of Technology, 1997. http://hdl.handle.net/1853/28042.

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19

Nissen, Jan Hendrick [Verfasser]. "Perfluorinated Dialkyl Peroxides : Their Properties And Syntheses From Perfluoroalkyl Hypohalites / Jan Hendrick Nissen." Berlin : Freie Universität Berlin, 2021. http://d-nb.info/1229436731/34.

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20

Holmström, Katrin. "Analysis of Perfluoroalkyl Acids in Swedish Biota : temporal trends, tissue distribution and toxicity /." Stockholm : Department of Applied Environmental Science (ITM), Stockholm University, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-34181.

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Diss. (sammanfattning) Stockholm : Stockholms universitet, 2010.
At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: Manuscript. Paper 4: Manuscript. Härtill 4 uppsatser.
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Ahmad, Husan. "Synthesis of Diazonium Perfluoroalkyl(Aryl) Sufonimide (PFSI) Zwitterions for Solid Acid Alkylation Catalysts." Digital Commons @ East Tennessee State University, 2015. https://dc.etsu.edu/honors/314.

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The final objective of this project is to create an environmentally friendly solid alkylation catalyst to replace the commercially available liquid acid catalysts, such as hydrofluoric acid and sulfuric acid, which are used in the petroleum industry. My research target is to synthesize the diazonium PFSI zwitterions, which can be chemically grafted on the silica as the solid alkylation catalyst. A 4-steps synthesis is designed to prepare the diazonium PFSI zwitterions. The first two steps were successfully completed in the lab. The first one is to prepare the starting material of 4-nitrobenzenesulfonamide from an ammonolysis reaction between 4-nitrobenzene sulfonyl chloride and ammonium hydroxide. And next, a base catalyzed coupling reaction was carried out with 4-nitrobenzenesulfonamide and commercially available perfluorobutane sulfonyl fluoride with nitrogen gas (N2) protection. The coupling product (I in Figure 1) was then purified by extraction and recrystallization. All chemicals in the synthesis procedure were characterized with proton NMR, fluorine NMR, Infrared (IR) spectroscopy and melting points.
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22

Söderlund, Lydia. "Method development of total oxidizable precursor assay for perfluoroalkyl acid precursors in domestic sludge." Thesis, Örebro universitet, Institutionen för naturvetenskap och teknik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-71046.

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Per- and polyfluoroalkyl substances (PFASs) are persistent organic pollutants used in industrial applications and are globally distributed in the environment. A group of PFASs that are difficult to measure with today’s method are perfluoroalkyl acid precursors (PFAA precursors) that, when degraded, serves as indirect sources of PFAAs. This study has optimized a previously developed method for quantification of PFAA precursors in soil; through total oxidizable precursor assay (TOP assay) under alkaline conditions, to be applicable on sewage sludge. To achieve and maintain an alkaline environment during the entire oxidative treatment, several parameters were tested: concentrations of NaOH, persulfate and sample; additional clean-up with graphitized non-porous carbon and reaction time. Solid phase extraction-weak anion exchange (SPE-WAX) was used for clean-up and separation of analytes, and LC-MS/MS was used for quantification. The optimal conditions with the highest levels of PFAAs detected was obtained with 1.33 M NaOH, 60 mM persulfate, 3.57 g/L sludge with a reaction time of 6 hours. The use of graphitized non-porous carbon reduced matrix effects on oxidative conversion resulting in a higher pH as well as a higher degree of oxidation, but with some analyte loss.
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23

Björklund, Justina. "Brominated flame retardants and perfluoroalkyl acids in Swedish indoor microenvironments : Implications for human exposure." Doctoral thesis, Stockholms universitet, Institutionen för tillämpad miljövetenskap (ITM), 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-63701.

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Humans are exposed to persistent organic pollutants (POPs) such as brominated flame retardants (BFRs, specifically polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecane (HBCD)) and perfluoroalkyl acids (PFAAs, specifically perfluoroalkane sulfonate (PFOS) and perfluorooctanoic acid (PFOA)). They are used in consumer products found in cars, offices, homes and day care centers. Diet was earlier thought to be a major human exposure route for legacy POPs, but does not account for body burdens found for many new POPs and indoor exposure from air and dust has been hypothesized as also important. In this thesis, BFRs in air and dust, and PFAAs in dust from different indoor microenvironments in Sweden were analysed, and the results used to estimate human exposure. BFRs and PFAAs were detected in dust from all microenvironments and PBDEs in all air samples. BFR and PFAA exposure occurs mostly in peoples’ homes with toddlers having higher intakes from dust ingestion than adults. Inhalation and dust ingestion play minor roles compared to diet for humans with median exposures, but in worst case scenarios, dust ingestion may be significant for a small part of the Swedish population. Sampling using home vacuum cleaner bag dust and researcher-collected above floor dust was compared. Correlations were seen for ∑OctaBDE and ∑DecaBDE but not for ∑PentaBDE and HBCD. Higher PBDE concentrations were found in above floor dust but higher HBCD concentrations were found in vacuum cleaner bag dust. BDE-47 concentrations were correlated between vacuum cleaner bag dust and breast milk, indicating exposure through dust ingestion. Similar concentrations of PBDEs were measured in indoor and outgoing air from day care centers, apartment and office buildings. Indoor air explained 54-92% of ∑PentaBDE and 24-86% of BDE-209 total emissions to outdoor air in Sweden, supporting the hypothesis that the indoor environment is polluting ambient air via ventilation systems.

At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 2: Accepted. Paper 3: Accepted. Paper 4: Manuscript.

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Alharbi, Helal, and Hua Mei. "SYNTHESIS OF DIAZONIUM N-(PERFLUOROALKYL) BENZENESULFONIMIDE ZWITTERIONIC POLYMERS FOR PROTON EXCHANGE MEMBRANE FUEL CELLS." Digital Commons @ East Tennessee State University, 2018. https://dc.etsu.edu/asrf/2018/schedule/197.

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The objective of the research is to synthesize the diazonium N-(perfluoroalkyl) benzenesulfonimide (PFSI) zwitterionic polymers as electrolytes in polymer electrolyte membrane (PEM) fuel cells. The proposed diazonium PFSI zwitterionic polymers are expected to enhance the thermal and chemical stability, increase the proton conductivity of electrolytes, and improve the catalyst efficiency in electrodes for PEM fuel cells. Synthesis of the perfluorobenzoyl peroxide initiator, homoplymerization of perfluoro (3-oxapent-4-ene) sulfonyl fluoride and coupling reaction with 4-nitrobenzene sulfonyl amide have been carried out successfully in the lab. All the intermediate chemicals are characterized by 1H NMR, 19F NMR and IR.
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Alharbi, Helal. "Synthesis of Diazonium N-(Perfluoroalkyl) Benzenesulfonimide Polymers for Proton Exchange Membrane Fuel Cells (PEMFCs)." Digital Commons @ East Tennessee State University, 2019. https://dc.etsu.edu/etd/3601.

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The objective of the research is to synthesize the diazonium N-(perfluoroalkyl) benzenesulfonimide (PFSI)zwitterionicpolymers as electrolytes in polymerelectrolyte membrane (PEM) fuel cells. The proposed diazoniumPFSI zwitterionic polymer (I) is expected to enhance the thermal and chemical stability, increase the proton conductivity of electrolytes, and improve the catalyst efficiency for PEM fuel cells. Synthesis of the perfluorobenzoyl peroxide initiator, homopolymerization of perfluoro (3-oxapent-4-ene) sulfonyl fluoride,coupling reaction with4-sulfamonylacetanilide, couplingreaction with 4-nitrobenzene sulfonyl amide, n-deacetylation reaction, and diazotization reactionhave been carried outsuccessfully in the lab. The intermediate chemicals are characterized by GC-MS, IR, NMR, and GPC spectroscopies.
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Frömel, Tobias Verfasser], and Martin [Akademischer Betreuer] [Jekel. "Biotransformation, trace analysis and effects of perfluoroalkyl and polyfluoroalkyl substances / Tobias Frömel. Betreuer: Martin Jekel." Berlin : Universitätsbibliothek der Technischen Universität Berlin, 2012. http://d-nb.info/1024771903/34.

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27

Filipovic, Marko. "Fate of perfluoroalkyl acids in the aquatic environment with a focus on mass balance studies." Doctoral thesis, Stockholms universitet, Institutionen för miljövetenskap och analytisk kemi, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-116228.

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Perfluoroalkyl substances (PFASs) are man-made chemicals. Their unique properties make them beneficial for a wide range of industrial and consumer product applications, such as in aqueous film forming foam (AFFF), durable water repellent clothing, hydraulic oils and food packaging materials. Perfluoroalkyl acids (PFAAs), a class of PFASs, are highly persistent in the environment, and long chain PFAAs are bioaccumulative and toxic. International regulation and voluntary actions by the industry have been implemented and led to a recent reduction of primary emissions of PFAAs to the environment. However, point sources such as AFFF training sites as well as diffuse sources continue to contaminate water bodies, soil and biota. Reducing environmental pollution with PFAAs has therefore become a regulatory priority. Designing successful measures to reduce the PFAA contamination requires an understanding of the sources, transport and fate of PFAAs in the environment. Four scientific publications are included in this PhD thesis, which aimed at increasing the holistic understanding of the fate of PFAAs in aquatic systems. This was achieved by chemical trace analysis combined with mass balance modeling. The following topics were covered: Dispersion and fate of PFAAs from an AFFF-impacted site (Paper I), recirculation of PFAAs in the aquatic environment with focus on waste water treatment plants (WWTPs, Paper II), mass balance of PFAAs in the Baltic Sea (Paper III) and transport and fate of PFAAs in two pristine boreal stream catchments (Paper IV). Results from Paper I showed that AFFF-impacted sites at a former military airfield, which was abandoned for more than 30 years, continue to be point sources of PFAAs to recipients. The sum of PFAAs in the ground water and surface waters ranged from 740 to 51000 ng L-1 and <0.5 to 79 ng L-1, respectively. PFOS in muscle tissue of European perch from a nearby lake ranged from 77 to 370 ng g-1 wet weight, representing among the highest values reported worldwide for fish muscle. In Paper II the relative importance of environmental recirculation of PFAAs versus new releases from the technosphere was investigated for PFAAs in WWTP influents. It was shown that tap water can be an important source of PFAAs to WWTPs in areas with elevated environmental levels. This needs to be taken into account when calculating emissions via WWTP effluents. PFAA mass balances over the WWTPs suggested that PFHxA and PFOA were formed from precursor compounds within the plants. Assembled PFAA mass balances for the Baltic Sea (Paper III) showed that river inflow and atmospheric deposition were the dominant input pathways, while wastewater treatment plant (WWTP) effluents discharging directly into the Baltic Sea made a minor contribution. The inputs of PFAAs were estimated to be higher than the outputs, suggesting a current increase of the PFAA inventory in the Baltic Sea. Also the mass balance study of PFAAs in two remote stream catchments presented in Paper IV revealed that inputs dominated over outputs for both catchments, indicating that a considerable portion of the PFAAs deposited from the atmosphere is retained in soil or in deep ground water and may be released to surface and marine water environments in the future
Perfluoralkilne tvari (PFASs) su umjetne kemikalije. Zbog svojih jedinstvenih svojstava široko su primjenjive u industriji i izradi proizvoda krajnje potrošnje kao što su pjena za gašenje požara (AFFF), vodootporna odjeća, hidraulična ulja i pakiranja za hranu. Perfluoralkilna kiselina (PFAAs) iz skupine perfluoralkilnih tvari iznimno je dugotrajna u okolišu, a dugolančane PFAAs su bioakumulativne i otrovne. Poduzeta međunarodna regulativa i dobrovoljne akcije vodile su nedavno smanjenoj primarnoj emisiji PFAAs u okoliš. Unatoč tome, primarni izvori, kao što su mjesta na kojima se provode treninzi za gašenje požara i difuzni izvori i dalje zagađuju vode, tlo i biotu. Zbog toga, smanjenje onečišćenja okoliša izazvanog PFAAs predstavlja regulatorni prioritet. Stvaranje uspješnih mjera kojima bi se smanjilo onečišćenje izazvano PFAAs zahtjeva razumijevanje izvora, prijenosa i sudbine tih tvari u okolišu. U ovaj doktorat uključena su četiri znanstvena članka kojima je cilj povećati sveukupno razumijevanje sudbine PFAAs u vodenim sustavima. To je postignuto kemijskom analizom elemenata u tragovima u kombinaciji s modeliranjem masene ravnoteže. Obrađene su sljedeće teme: Širenje i sudbina PFAAs na područjima zahvaćenim AFFF (Članak I), ponovna cirkulacija PFAAs u vodenom okolišu s naglaskom na postrojenja za pročišćavanje otpadnih voda (Članak II), masena ravnoteža PFAAs u Baltičkom moru (Članak III) te prijenos i sudbina PFAAs u dva udaljena sjeverna vodena toka (Članak IV).   Rezultati iz Članka I pokazali su da su područja zahvaćena AFFF na bivšem vojnom aerodromu napuštenom prije 30 godina i dalje je glavni izvor PFAA zagadenja okolisa. Zbroj PFAAs u podzemnim i površinskim vodama kreće se u rasponu od 740 do 51000 ng L-1 i <0.5 do 79 ng L-1. PFOS u mišićnom tkivu grgeča iz obližnjeg jezera kreće se od 77 do 370 ng g-1 mokre težine, predstavljajući jednu od najviših vrijednosti u svijetu za riblje mišiće. Članak II istražuje relativnu važnost ponovne cirkulacije PFAAs imajući na umu novu emisiju PFAAs iz tehnosfere u postrojenjima za pročišćavanje otpadnih voda. Cirkulacija/kruženje u okolišu može se pojaviti kada PFAAs iz sustava pitke voda (rijeka, bunara i jezera) odlaze u otpadne vode. Prikazano je kako voda iz slavine može biti važan izvor PFAAs sustavima za pročišćavanje otpadnih voda u područjima s povišenim razinama zaštite okoliša. To se treba uzeti u obzir pri računanju emisije putem strojeva koji se koriste za pročišćenje otpadnih voda. Masena ravnoteža PFAA u postrojenjima za pročišćavanje otpadnih voda upućuje na to da su PFHxA i PFOA stvoreni kao prethodni spojevi unutar postrojenja. Prikupljene masene ravnoteže PFAA za Baltičko more (Članak III) pokazale su da su pritoke rijeka i atmosfersko taloženje dominantni ulazni putovi, dok postrojenja za pročišćenje otpadnih voda pridonose tek u manjoj mjeri. Ulaz PFAAs je procijenjen višim od izlaza, što objašnjava trenutno povećanje sadržaja PFAA u Baltičkom moru. Masena ravnoteža PFAAs u dva udaljena riječna toka predstavljena u Članku IV otkriva da ulaz dominira nad izlazom za oba riječna toka, što upućuje na značajan udio PFAAs koji je iz atmosfere zadržan u tlu ili podzemnim vodama te može biti ispušten u područja površinskih voda i mora.
Perfluorerade alkylsyror (PFAA) är kemikalier som är producerade av människan. Deras unika egenskaper gör att de kan användas i många olika industriella applikationer. PFAAs används i brandsläckningsskum, vattenavvisande kläder, hydrauliska oljor och matförpackningar. PFAAs har visat sig vara persistenta i miljön, och långkedjiga PFAA-homologer har visat sig vara bioackumulerbara samt ha en toxisk verkan. Reglering på internationell nivå tillsammans med initiativ från industrin har lett till minskning av direkta utsläpp. Punktkällor som brandövningsplatser samt andra diffusa källor fortsätter att förorena omgivande vattendrag, jordlager och fauna. Den utbredda föroreningen av PFAAs har därför blivit prioriterad för reglering. För att förstå utsläppen av PFAAs i miljön, hur de transporteras samt deras öde i miljön, är det viktigt att utföra studier som belyser dessa områden.   Denna doktorsavhandling inkluderar fyra vetenskapliga publikationer. Syftet med de underliggande studierna var att öka den holistiska förståelsen av PFAAs rörelse i akvatiska system. Studierna gjordes genom att kombinera kemiska analysmetoder med modellering. Följande  studier genomfördes; Transport och spridning av PFAAs från en brandövningsplats (Paper I), recyklering av PFAAs i den akvatiska miljön med fokus på vattenreningsverk (Paper II), massbalans av PFAAs i Östersjön (Paper III), transport och öde av PFAAs i två pristina vattendrag (Paper IV).   Resultat från (Paper I) visade att brandövningsplatser vid en flygplats som inte har varit i bruk i mer än 30 år, fortfarande är punktkällor av PFAAs till omgivande vattendrag. Summan av PFAAs koncentrationer i grundvattnet och ytvattnet sträckte sig från 740 till 51000 ng L-1 och <0.5 till 79 ng L-1 i respektive vattendrag. Koncentrationen av PFOS i muskelvävnad från  aborre i en av sjöarna var 77 till 370 ng g-1 våtvikt. Dessa värden representerar några av de högsta uppmätta koncentrationerna i världen. I Paper II testades betydelsen av PFAAs från recirkulering i miljön i jämförelse med nya utsläpp från teknosfären. Recirkulering av PFAAs i miljön kan förekomma då PFAAs i inkommande vatten till reningsverk kommer från dricksvatten. Denna studie visar att dricksvatten kan vara en påtaglig källa av PFAAs till vattenreningsverk i områden med förhöjda halter av PFAAs i miljön. Detta måste tas hänsyn till när man beräknar emissioner med utgående vatten från vattenreningsverk. Massbalanser av PFAAs i reningsverken visar att PFHxA och PFOA bildades av prekursorämnen i vattenreningsverken. I Paper III beräknades massbalanserna av PFAAs i Östersjön, beräkningarna visar att floder och atmosfärisk nedebörd var de viktigaste källorna medan utsläppen från vattenreningsverk var markant lägre. Importen av PFAAs estimerades vara högre än exporten, varför vi tror att PFAAs mängden I Östersjön kommer att öka över tid. Vidare gjordes en mass balans av PFAAs i två avlägsna avrinningsområden (Paper IV). Resultaten visar att importen av PFAAs dominerar över exporten från båda avrinningsområdena. Detta indikerar att en stor del av PFAAs som kommer ner via nederbörd kommer att ansamlas i jorden eller i grundvattnet. Dessa PFAAs kan vid senare tillfälle komma att släppas ut till floder som rinner ut i marina vatten.

At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 2: Manuscript.

 

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28

Goosey, Emma Rae. "Towards understanding the fate of perfluoroalkyl compounds (PFCs) within urban environments : implications for human exposure." Thesis, University of Birmingham, 2010. http://etheses.bham.ac.uk//id/eprint/1052/.

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Perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) have been detected across the globe in a variety of media. The toxicity of these compounds and other precursors has led to concern about human exposure. The purpose of this thesis is to investigate the presence of perfluoroalkyl compounds (PFCs) in UK indoor and outdoor microenvironments and the impact this may have on human exposure. Both PFOS and PFOA were chosen for analysis (via LC-ESI-MS/MS) because of their highly persistent behaviour. Additionally, perfluorohexane sulfonate (PFHxS), was chosen along with precursors to PFOS and PFOA; perfluorooctane sulfonamides (PFOSAs) and perfluorooctane sulfonamidoethanols (PFOSEs). An international comparison of house dust was conducted and concentrations of PFCs in the UK (except for ethyl perfluorooctane sulfonamide (EtFOSA)) were found to be similar to those from France, Germany, USA, Canada and Australia and much greater than from homes in Kazakhstan and Thailand. Concentrations of EtFOSA were significantly higher in house dust samples from Australia compared to the UK, and were raised in all other countries. The reason for this is uncertain, but is speculated to derive from the use of EtFOSA as an active ingredient in Sulfluramid, which is an insecticide used for control of ants, cockroaches and termites.
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Herrick, Robert L. "Exposure to Perfluoroalkyl Compounds and Resultant Effects on Cholesterol in the Mid Ohio River Valley." University of Cincinnati / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=ucin155421475631607.

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30

Maisonet, Mildred, Simo Näyhä, Debbie A. Lawlor, and Michele Marcus. "Prenatal Exposures to Perfluoroalkyl Acids and Serum Lipids at Ages 7 and 15 in Females." Digital Commons @ East Tennessee State University, 2015. https://dc.etsu.edu/etsu-works/29.

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Background In some cross-sectional epidemiologic studies the shape of the association between serum concentrations of perfluoroalkyl acids (PFAAs) and lipids suggests departures from linearity. Objectives We used statistical approaches allowing for non-linearity to determine associations of prenatal exposures of perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) with lipid concentrations. Methods PFAAs were measured in serum from pregnant women collected in 1991–1992 at enrollment in the Avon Longitudinal Study of Parents and Children and lipids in serum from their daughters at ages 7 (n = 111) and 15 (n = 88). The associations of PFAAs with lipids were first explored by cubic splines, followed by piecewise linear regressions by tertiles to obtain regression coefficients (β) and their 95% confidence limits (95% CL) (in mg/dL per 1 ng/mL). Results At age 7, total cholesterol was positively associated with prenatal PFOA concentrations in the lower tertile (β = 15.01; 95% CL = 2.34, 27.69) but not with PFOA concentrations in the middle (β = − 3.63; 95% CL = − 17.43, 10.16) and upper (β = − 1.58; 95% CL = − 4.58, 1.42) tertiles. At age 15, a similar pattern was noted as well. Positive associations between LDL-C and prenatal PFOA concentration in the lower tertile were observed in daughters at ages 7 (β = 14.91; 95% CL = 3.53, 28.12) and 15 (β = 13.93; 95% CL = 0.60, 27.26). LDL-C was not associated with PFOA concentrations in the middle or upper tertile at any age. Neither HDL-C nor triglycerides was associated with prenatal PFOA exposure. Non-linear patterns of association of total cholesterol and LDL-C with prenatal PFOS were less consistently noted. Conclusion Exposure to low levels of PFOA during prenatal development may alter lipid metabolism later in life. Given the small sample size further replication of the association in large independent cohorts is important.
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Phillips, Sophie Harden. "Investigating childhood health outcomes linked to perfluoroalkyl acid exposure in Australia: A temporal trend analysis." Thesis, Queensland University of Technology, 2018. https://eprints.qut.edu.au/123737/1/Sophie_Phillips_Thesis.pdf.

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This project investigated temporal trends in per-fluoroalkyl acid concentrations in Australian children between 2002 and 2017. Temporal trends in chemical concentrations were then compared with modelled burden of disease data in order to direct future research into the health effects associated with exposure. Between 2002 and 2017, there was a significant decrease in perfluoroalkyl acid concentrations within Australia's child population, but there was no correlation between this and burden of disease in the same age group.
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Cassone, Cristina. "Effects of Perfluoroalkyl Acids on In Ovo Toxicity and Gene Expression in the Domestic Chicken (Gallus gallus domesticus)." Thèse, Université d'Ottawa / University of Ottawa, 2012. http://hdl.handle.net/10393/23162.

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Perfluoroalkyl acids (PFAAs) are a family of synthetic substances used in a wide variety of consumer and industrial applications, including non-stick and stain-resistant products. PFAAs, specifically perfluorinated sulfonates and carboxylates, are chemically stable and virtually non-biodegradable in the environment. In recent years, PFAAs have been detected in tissues and blood of humans and wildlife. Furthermore, PFAAs have a tendency to bioaccumulate and biomagnify in biota. Perfluorooctane sulfonate and perfluorooctanoate are known to be toxic when animals are exposed to environmentally-relevant levels, but scientists and regulators are challenged with determining and predicting their modes of action. There is some evidence to suggest that PFAAs can impact the thyroid hormone (TH) pathway and neurodevelopment. The studies presented in this thesis investigated the developmental effects and potential modes of action of newer PFAAs that are being introduced into the global market place. Egg injection experiments were performed in domestic chicken (Gallus gallus domesticus) embryos to assess the in ovo toxicity of perfluorohexane sulfonate (PFHxS) and perfluorohexanoate (PFHxA) during development. Real-time RT-PCR was used to measure the transcription of candidate genes in the liver and cerebral hemisphere of day 21-22 embryos. Candidate genes were selected based on their responsiveness to PFAA exposure in an in vitro screening assay conducted previously. In ovo exposure to PFHxS decreased embryo pipping success and overall growth at 38,000 ng/g; several orders of magnitude higher than concentrations reported in wild bird eggs. The expression of TH-responsive genes, including type II and III 5'-deiodinase, neurogranin, and octamer motif binding factor 1, were induced. In addition, PFHxS diminished free thyroxine (T4) levels in plasma. PFHxA had no affect on pipping success, gene expression or T4 levels in chicken embryos at the doses assessed. The transcriptional profiles in the cerebral hemisphere of chicken embryos exposed to 890 and 38,000 ng/g PFHxS were compared to a solvent control using microarray technology. The expression of 78 different genes were significantly altered (fold change > 1.5, p < 0.001) by PFHxS. Functional analysis showed that PFHxS affected genes involved in tissue development and morphology and cellular assembly and organization. Pathway and interactome analysis suggested that gene expression may be affected through integrin receptors and signaling pathways via TH–dependent and –independent modes of action. It is expected that the findings presented in this thesis will be of general relevance and importance to regulatory agencies and of interest to research scientists and risk assessors.
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O'Brien, Jason. "The Effects of Perfluoroalkyl Compounds on In Ovo Toxicity and Hepatic mRNA Expression in the Domestic Chicken (Gallus gallus domesticus)." Thèse, Université d'Ottawa / University of Ottawa, 2011. http://hdl.handle.net/10393/19924.

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Perfluoroalkyl compounds (PFCs) are a group of chemical surfactants most notably used in non-stick and stain-resistance applications. Due to their wide-spread use and inherent resistance to degradation, several PFCs have become persistent environmental contaminants. Despite the high concentrations of PFCs reported in wild birds and their eggs, very little is known about the toxicological effects they have on avian species. This thesis investigates the developmental toxicity of PFCs in an avian model species: the domestic chicken (Gallus gallus domesticus). Egg injection experiments were performed to assess the in ovo toxicity of perfluorooctane sulfonate (technical grade, T-PFOS), perfluorooctanoic acid (PFOA), perfluorodecane sulfonate (PFDS) and perfluoroundecanoic acid (PFUdA). Real-time RT-PCR was then used to measure the transcription of candidate biomarker genes in the liver tissue of day 20 embryos. Candidate genes were selected based on their responsiveness to PFC exposure in previously conducted in vitro screening assays. In ovo exposure to PFOS resulted in a dose-dependent decrease in embryo pipping success (a measure of hatching success) with an LD50 of 93 μg/g (3.54 μg/g-672,910 μg/g, 95% confidence interval), however the expression of peroxisome proliferator-activated receptor alpha (PPARα)-regulated genes was not affected in liver tissue as hypothesized. PFOA, PFDS and PFUdA had no effect on the pipping success of chicken embryos. The expression of cytochrome P450 1A4 (CYP1A4) and liver fatty acid binding protein (L-FABP) mRNA increased in embryo liver tissue following in ovo exposure to PFUdA but was only statistically significant at 10 μg/g, which is several orders of magnitude higher than concentrations reported in wild bird eggs. The isomer-specific accumulation of PFOS in chicken embryo livers was also investigated using an in-port derivatization gas-chromatography/mass spectrometry (GC-MS) method. Prior to incubation, chicken eggs were injected with T-PFOS, composed of 63% linear isomer (L-PFOS) and 37.3% branched isomers. The isomer profiles in day-20 embryo liver tissue showed up to 20% enrichment in the proportion of L-PFOS, compared to T-PFOS, with a corresponding decrease in the proportion of branched isomers. This enrichment was inversely proportional to dose. Finally, the transcriptional profiles of cultured chicken embryonic hepatocytes (CEH) exposed to either T-PFOS or L-PFOS were compared using Agilent 4x44k Chicken (V2) Gene Expression microarrays. At equal concentrations (10 μM), T-PFOS altered the expression of significantly more genes (340 genes, >1.5 fold change, false discovery rate adjusted p<0.05) compared to L-PFOS (130 genes). Functional analysis showed that L-PFOS and T-PFOS affected genes involved in lipid metabolism, cellular growth and proliferation, and cell-cell signaling. Pathway and interactome analysis suggested that gene expression may be affected through RXR, oxidative stress response, TP53 signaling, MYC signaling, Wnt/β-catenin signaling and PPARγ and SREBP receptors. In all functional categories and pathways examined, T-PFOS had a more pronounced disruptive effect on transctional regulation than L-PFOS. In summary, egg injection experiments showed that T-PFOS (but not linear PFOA, PFDS or PFUdA) may affect the hatching success of the chicken at environmentally relevant concentrations. It was also demonstrated that the accumulation of PFOS in embryonic liver is isomer specific, and leads to an enrichment of L-PFOS. The increased transcriptional disruption caused by T-PFOS in cultured hepatocytes over L-PFOS suggests that the branched isomers may be largely responsible for the toxicological effects of PFOS. Combined, the results from this thesis demonstrate the importance of considering PFOS isomer burdens during risk assessment. In addition, gene expression analysis identified several candidate mechanisms for PFOS toxicity.
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Gudmunsen, David. "The synthesis, coordination chemistry and catalytic applications of phosphinite, phosphonite and phosphite ligands containing perfluoroalkyl substituents." Thesis, University of Leicester, 2000. http://hdl.handle.net/2381/30048.

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A review is presented of the development and application of liquid-liquid biphase systems in homogeneous catalysis and the concept and application of fluorous biphase systems (FBS) in catalysis. Novel monodentate phosphorus(III) ligands of general formula PhxP(OC6H4-4-C6F,3)3.x and PhCHF-* (x = 0, 1 or 2), and the phosphite ligands P(OC6H4-4-C8Fl7)3, P(OC6H4-4-C10F2i)3, P(OC6H4-3-C6F13)3 and P(OC6H4-2-C6Fi3)3 have been synthesised and fully characterised by 'H, 19F and 3,P{1H} NMR spectroscopy, mass spectrometry and elemental analysis. The monodentate phosphinite, phosphonite and phosphite ligands (L) have been reacted with a variety of transition metal complexes to form complexes of the type cis- and trans- MC 2L2 (M = Pt, Pd), cw- PtCl2(PEt3)L , M(n5-C5Me5)Cl2L (M = Ir, Rh) and RI1CIL3 . The complexes have been isolated and characterised using analytical techniques including H, 19F and 31P{!H} NMR spectroscopy, mass spectrometry, IR spectroscopy, X-ray crystallography and elemental analysis. The steric and electronic influences of the perfluoroalkyl substituents on the chemical and physical properties of the metal complexes have been assessed by comparison of their spectroscopic and structural data with that for their related protio complexes. Preliminary catalytic studies involving P(OC6H4-4-C6Fi3)3 as a modifying ligand in the rhodium-catalysed hydroformylation of 1-hexene and 1-nonene under FBS conditions have been undertaken. The influence of the perfluoroalkyl substituents on the rate of reaction, product selectivity and catalyst/product separation has been examined. The synthesis of bidentate phosphonite and phosphite ligands containing perfluoroalkyl substituents has been investigated. The derivatised bidentate phosphonite ligands (C6F13-4-C6H40)2PCH2CH2P(OC6H4-4-C6F, 3)2 and {5,5' - (C6F13)2-2,2,-02C,2H6}PCH2CH2P{2,2,-02C,2H6-5,5,-(C6F13)2} (L-L) have been reacted with transition metal complexes to form coordination complexes of the type PtCl2(L-L) and Rh(u-C1)(L-L)]2.
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35

Ullah, Shahid. "Improved analytical methods for perfluoroalkyl acids (PFAAs) and their precursors – a focus on human dietary exposure." Doctoral thesis, Stockholms universitet, Institutionen för tillämpad miljövetenskap (ITM), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-93719.

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Per- and polyfluoroalkyl substances are a large group of global environmental contaminants. They can be divided into two sub-groups, 1) perfluoroalkyl acids (PFAAs) and 2) so called precursors, i.e. compounds that can potentially be transformed to form PFAAs. PFAAs are today ubiquitous in wildlife and humans. Food and drinking water are assumed to be the dominant human exposure pathways for PFAAs. The main aim of this doctoral thesis was to develop highly sensitive and fully validated analytical methods for the determination of a range of PFAAs and selected precursors in dietary samples. The methods were based on liquid chromatography coupled to mass spectrometry. Samples were extracted by solvent extraction followed by a cleanup step employing solid phase extraction. The cleanup step could at the same time be used as a fractionation of ionic PFAAs and neutral precursors. Paper I and II describe the development of methods for simultaneous analysis of three groups of PFAAs including perfluoroalkyl phosphonic acids (PFPAs) in drinking water and food. Methyl piperidine was used as ion pairing agent, leading to highly sensitive analysis of PFPAs. A first screening of tap water samples and different food items revealed that human dietary exposure to PFPAs in Europe is currently not of concern. A novel method for simultaneous analysis of perfluoroalkyl carboxylic acids (PFCAs) and polyfluoroalkyl phosphate esters (PAPs) in food and packaging materials is described in paper III. Targeted food samples and their packaging were analyzed. The results showed that PAPs may contribute to human exposure to PFCAs. In paper IV temporal trends (1991-2011) of perfluorooctane sulfonic acid (PFOS) and its precursors in herring were investigated. Rapidly decreasing trends were found for precursors, whereas PFOS did not show a significant change over time. Precursors in fish may have played an important role for human exposure to PFOS in the 1990s but are probably negligible today.

At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 4: Manuscript.


PERFOOD project (KBBE-227525)
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36

Blévin, Pierre. "Physiological consequences of exposure to perfluoroalkyl substances, organochlorine compounds and mercury in an Arctic breeding seabird." Thesis, La Rochelle, 2018. http://www.theses.fr/2018LAROS023/document.

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A cause d’une anthropisation toujours plus forte des écosystèmes, de plus en plus de menaces pèsent sur la biodiversité. Parmi celles-ci, l’exposition aux contaminants est particulièrement problématique pour les organismes vivants. Emis et utilisés dans les pays industrialisés, ces contaminants hautement persistants dans l’environnement vont gagner les régions polaires puis se bio-accumuler dans les organismes vivants au cours du temps et se bio-amplifier le long du réseau trophique. Ainsi, les oiseaux marins, longévifs et situés dans les maillons supérieurs de la chaine alimentaire, sont particulièrement exposés et vulnérables à une exposition chronique à ces contaminants. A travers une perturbation endocrinienne, ces contaminants vont pouvoir impacter certains mécanismes physiologiques et traits comportementaux, entrainant in fine des conséquences à long-terme sur la fitness des individus et populations. Ma thèse s’articule autour de trois grandes familles de contaminants : i) les composés perfluoroalkylés (PFASs), encore largement utilisés dans plusieurs secteurs industriels et agricoles et en augmentation dans l’environnement ; (ii) les composés organochlorés dits « d’héritage » (OCs), interdits depuis des années mais entrainants toujours des effets délétères sur la biodiversité et (iii) le mercure (Hg), métal lourd non-essentiel ayant une origine à la fois anthropique et naturelle. Basé sur une approche corrélative in natura, je me suis intéressé aux conséquences physiologiques et comportementales d’une exposition chronique à ces trois grandes familles de contaminants présents chez la mouette tridactyle (Rissa tridactyla) de l’Arctique Norvégien (Svalbard) au cours de son cycle reproducteur (depuis l’accouplement jusqu’à l’élevage des poussins). Spécifiquement, j’ai étudié les relations entre ces contaminants et la fertilité (morphologie et motilité des spermatozoïdes), l’expression des signaux sexuels (visuel : coloration des téguments, olfactif : signature chimique), les comportements de soins parentaux (température d’incubation et rotation de l’œuf), le vieillissement cellulaire (longueur des télomères) et la dépense énergétique (métabolisme de base). Je me suis également penché sur de potentiels mécanismes sous-jacents permettant d’expliquer ces relations. Puisque ces mécanismes physiologiques et comportementaux sont fortement impliqués dans la valeur sélective des individus, les possibles conséquences à long terme de cette exposition sur la reproduction et survie des individus sont discutées. Ce travail permet de souligner la forte toxicité de certains composés organochlorés « historiques » (en particulier les chlordanes) et d’apporter de toutes nouvelles connaissances sur la toxicité très mal connue des PFASs chez la faune sauvage. Fait important, ce travail de thèse révèle que les PFASs et les OCs pourraient agir de manière contrastée sur plusieurs mécanismes physiologiques et traits comportementaux. Spécifiquement, une forte exposition à l’oxychlordane, un métabolite du chlordane, pesticide interdit depuis des décennies, est associée à des télomères plus courts, une réduction du métabolisme de base et à une moindre capacité à incuber les œufs. A l’inverse, on observe une élongation des télomères, une augmentation du métabolisme de base et une rotation des œufs accrue chez les individus les plus exposés aux PFASs. Le Hg, au moins en ce qui concerne les paramètres étudiés, ne semble pas jouer un rôle majeur. Cette étude souligne l'importance de tenir compte de plusieurs groupes de contaminants lorsqu'on étudie les conséquences de l'exposition aux contaminants environnementaux chez la faune sauvage
Due to increasing human activities, a growing number of threats are challenging the fate of biodiversity. Among them, environmental contamination is particularly concerning for living organisms. Used and released in industrialized countries, these highly persistent contaminants can reach remote areas such as the Arctic ecosystem and will biomagnify though food webs and bioaccumulate in organisms. Long-lived seabirds are located in the upper levels of the food chains and thus particularly exposed and sensitive to a chronic contaminants exposure. Through endocrine disruption, these contaminants can impact physiological mechanisms and behavioural traits, inducing in fine, long-term fitness consequences on individuals and populations. My thesis focuses on three groups of contaminants: (i) poly- and perfluoroalkyl substances (PFASs), still broadly used in a vast array of industrial processes and increasing in the Arctic; (ii) “legacy” organochlorine contaminants (OCs, pesticides and industrial compounds), banned from use but still well present in the Arctic and (iii) mercury (Hg), a non-essential metal coming of both natural and anthropic origins. Based on a correlative approach conducted in natura, I investigated the physiological and behavioural consequences of exposure to these contaminants during the whole breeding cycle (from pre-laying to chick-rearing period) in an Arctic seabird, the black-legged kittiwake (Rissa tridactyla) from Svalbard, Norwegian Arctic. Specifically, I examined the relationships between several PFASs, OCs, Hg and fertility (sperm morphology and motility), sexual signaling (visual: integument coloration and olfactory: chemical signature), parental care behaviors (incubation temperature and egg-turning), ageing (telomere length) and energy expenditure (basal metabolic rate). In addition, some potential underlying mechanisms were also studied to better understand the way through which contaminants can be detrimental for kittiwakes. Furthermore, since physiological mechanisms and behavioral traits investigated here are tightly involved in self maintenance and reproduction, possible effects on fitness are then discussed. This PhD work underlines the major role of certain legacy chlorinated organic compounds (e.g. chlordanes) and significantly contributes at documenting the poorly known toxicological consequences of PFASs exposure in wildlife. Importantly, this PhD shows that PFASs and OCs could impact ageing, energy expenditure and some parental care behaviors in a contrasted manner. Specifically, oxychlordane, a metabolite of a banned organochlorine pesticide was associated with decreased telomere length, lowered metabolic rate and reduced ability to incubate the eggs. Conversely, elongated telomere, increased BMR and enhanced egg rotation were observed in birds bearing the highest concentrations of PFASs. Finally, at least for the considered endpoints, Hg appears as a coming minor threat for kittiwakes. This study highlights the importance of considering several groups of contaminants when investigating the consequences of environmental contaminants exposure in wildlife
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Skoglund, Oskar. "Evaluation of bark material and granulated active carbon for treatment of perfluoroalkyl substances (PFASs) in wastewater." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-317453.

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Per- and polyfluoroalkyl substances (PFASs) are a group of artificial chemicals which have been used in a wide area of applications such as surface protection agents in cloths and different industrial applications. It has been found that PFASs are potentially toxic and are frequently found in the environment due to their persistent and mobile properties. Effluents from wastewater treatment plants (WWTPs) have been identified as an important point source of PFASs. Bark, by-product from the paper and wood industry, is a low-cost adsorbent and has the potential to be used as a filter material for PFASs in WWTPs. In this study, the removal of PFASs in wastewater has been investigated using granulated active carbon (GAC) (n = 2) and bark (n = 2) in a pilot scale experiment at Kungsängsverket, Uppsala over a period of five weeks. The specific objects included: i) investigate the influence of flow-rate (10, 30 40 and 60 Ld-1 ) on the removal efficiency of PFASs in the GAC and bark filters, ii) investigate the influence of particle size of bark on the removal efficiency of PFASs and iii) establish what circumstances that potentially promotes removal of PFASs in GAC and bark filters. The results showed that GAC was the most effective method compared to bark, with a reduction of 73-93%, with increasing efficiency under low flow (10-30 L d-1 ) conditions. The removal efficiency of bark was 45% with a particle size of 2-5 mm and under low flow conditions (10-30 L d-1 ), while under high flow conditions (60 L d-1 ) with the same particle size the removal of PFASs was not efficient, instead the total PFAS concentration increased with 40%. In contrast, bark with a particle size of 5-7 mm proved to be not efficient in removing PFASs (removal efficiency = 0%). In general, the removal efficiency increased with smaller particle size of the adsorbent and lower flow rate. The results indicate that bark may be a low-cost alternative in reducing PFASs from wastewater, under certain conditions.
Per- och polyfluroalkyla ämnen (PFAS) är en familj av artificiella fluorerade organiska föreningar som har använts sedan 1950-talet i en rad olika applikationer, såsom impregnering i kläder. Studier har visat att PFAS är potentiellt toxiska och att de förekommer globalt på grund av deras persistenta och mobila egenskaper. Spillvatten från avloppsreningsverk etablerats som en betydande källa för PFAS. Bark, vilket är en biprodukt från pappers- och träindustrin, är ett poröst material vilket möjligen kan användas som adsorbent av PFAS. Denna studie har jämfört effektiviteten hos granulerat aktivt kol (GAC) och bark för att minska PFAS i avloppsvatten. Experimentet var utformat som ett småskaligt kolonn-experiment vid Kungsängsängsverket, Uppsala, och pågick under en fem veckors period. Frågeställningen var att i) studera vilka effekter flödes-hastigheten (10, 30, 40 och 60 L d-1 ) har på reduktionen av PFAS hos GAC och barkfiltren, ii) studera vilka effekter partikelstorleken hos bark har på reduktion av PFAS och iii) redogöra vilka förhållanden som potentiellt gynnar reduktionen av PFAS i GAC och bark filtren. Resultaten visade att GAC var det mest effektiva av de två materialen, med en total reduktion på 73- 93% av PFAS, med ökande effektivitet under låga flödesförhållanden (10-30 L d-1 ). Bark minskade den totala mängden av PFAS med 45% då partikelstorleken var 2-5 mm och under låga flödesförhållanden (10-30 L d-1 ) medan bark med samma partikelstorlek under ökade flödesförhållanden (60 L d-1 ) visade en ökning på 40% av PFAS i det utgående vattnet. Bark med en partikelstorlek på 5-7 mm visade ingen reduktion av PFAS. Generellt visade resultaten att reduktionen av PFAS ökar under låga flödesförhållanden och minskad partikelstorlek. Resultaten visade att bark kan vara ett alternativt material för att minska PFAS i avloppsvatten förutsatt att gynnsamma förhållanden upprätthålls.
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MOHD, REDZUAN BIN RAMLI. "EVALUATION OF PERFLUOROALKYL ACIDS (PFAAs) IN WATER ENVIRONMENT, FOOD, AND HUMAN BODY IN KLANG VALLEY, MALAYSIA." Kyoto University, 2019. http://hdl.handle.net/2433/244539.

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39

Sandblom, Oskar. "Waste Incineration as a Possible Source of Perfluoroalkyl Acids to the Environment – Method Development and Screening." Thesis, Stockholms universitet, Institutionen för tillämpad miljövetenskap (ITM), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-161736.

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Atmospheric deposition has been suggested to be a major input pathway of perfluoroalkyl acids (PFAAs) to the Baltic Sea catchment area and to the Baltic Sea itself. However, the sources of PFAAs to the atmosphere are not well characterized. In this study we investigated if waste incineration plants in Sweden could be a source of PFAAs to the atmosphere and to the environment in general. Samples of the end products from waste incineration were collected at four different incineration plants. The plants differed in size and technical advancement and were considered to be representative for the majority of waste incineration plants in Sweden. The collected samples were slag from the furnaces, fly ash from the flue gases, “bambergkaka” (a mix of fly ash and sludge from wastewater treatment) as well as condensate and wastewater from the cleaning process of the flue gases. Two methods were developed, one for analysis of PFAAs in solid samples and one for water samples. Method validation showed good performance for both methods in terms of precision and accuracy, despite low recoveries obtained for the method for solid samples. The results from sample analysis revealed that PFAAs were present in all solid samples at concentrations in the low to sub ng/g range and in all but one condensate and wastewater samples at concentrations in the low to sub ng/L range. The quantified concentrations were used to estimate the potential annual discharges of PFAAs from waste incineration plants to the environment. Emission scenarios via landfills, via wastewater treatment plants and to the atmosphere were considered. The main conclusion of this study is that waste incineration in Sweden is not a significant source of PFAAs to the atmosphere or to the environment in general.
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Fujii, Yukiko. "Analysis of Perfluoroalkyl Carboxylic Acids in Composite Dietary Samples by Gas Chromatography/Mass Spectrometry with Electron Capture Negative Ionization." 京都大学 (Kyoto University), 2014. http://hdl.handle.net/2433/188708.

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Vongphachan, Viengtha. "Effects of Perfluoroalkyl Compounds (PFCs) on the mRNA Expression Levels of Thyroid Hormone-responsive Genes in Primary Cultures of Avian Neuronal Cells." Thesis, Université d'Ottawa / University of Ottawa, 2011. http://hdl.handle.net/10393/19791.

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There is a growing interest in assessing the neurotoxic potential and endocrine disrupting properties of perfluoroalkyl compounds (PFCs). Several studies have reported in vitro and in vivo effects related to neuronal development, neural cell differentiation, pre- and post- natal development and behaviour. PFC exposure altered hormone levels (e.g. thyroid hormone, estrogen, and testosterone) and the expression of hormone-responsive genes in mammalian and aquatic species. Hormone-mediated events are critical in central nervous system development and function, especially those controlled by thyroid hormones (THs). The studies presented in this thesis are the first to assess the effects of PFCs on primary cultures of neuronal cells in two avian species; the domestic chicken (Gallus domesticus) and herring gull (Larus argentatus). The following TH-responsive genes were examined using real-time RT-PCR: type II iodothyronine 5’-deiodinase (D2), D3, transthyretin (TTR), neurogranin (RC3), octamer motif binding factor (Oct-1), and myelin basic protein (MBP). Several PFCs were shown to alter mRNA expression levels of genes associated with the TH pathway in avian neuronal cells. It was determined that short-chained PFCs (<8 carbons) altered the expression of TH-responsive genes to a greater extent than long-chained PFCs (≥8 carbons). Although several significant changes in mRNA expression were observed in TH-responsive genes following PFC exposure in chicken embryonic neuronal (CEN) cells (Chapter 2), there were fewer changes in herring gull embryonic neuronal (HGEN) cells (Chapter 3). The mRNA levels of D2, D3, TTR, and RC3 were altered following treatment with several short-chained PFCs in CEN cells. Oct-1 and RC3 expression were induced following treatment with several short-chained PFCs in HGEN cells. These studies are the first to report that PFC exposure alters mRNA expression in primary cultures of avian neuronal cells and provide insight into the possible mechanisms of action of PFCs in the avian brain.
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42

Abban, Grace. "Methodology Study of N-deacetylation of 4-acetamido-perfluoroalkylbenzenesulfonimide." Digital Commons @ East Tennessee State University, 2015. https://dc.etsu.edu/etd/2553.

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In order to improve the synthetic route for diazonium perfluoroalkyl benzenesulfonylimide (PFSI) zwitterionic monomers, N-deacetylation of the coupling product was proposed to replace the reduction of aromatic amine intermediates. A series of hydrolysis methods, such as acid and base catalyzed refluxing, were explored for the N-deacetylation to obtain the PFSI aromatic amine. Factors such as temperature, concentration of acid/base and the time needed for the reaction to take place were investigated in an attempt to optimize the reaction condition. The basic hydrolysis was preferred since it was expected to carry out the N-deacetylation and debromination in one batch reaction. N-deacetylation in base at high concentrations was successful, however, side reaction of the perfluorovinyl ether occurred. It was discovered that the best N-deacetylation method is to reflux/sonicate the coupling product with acid in methanol for six hours. The intermediates and purified products were characterized with 1HNMR, 19FNMR, GC-MS and IR.
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43

Nworie, Chimaroke. "Synthesis of a 4-(Trifluoromethyl)-2-Diazonium Perfluoroalkyl Benzenesuflonylimide (PFSI) Zwitterionic Monomer for Proton Exchange Membrane Fuel Cell." Digital Commons @ East Tennessee State University, 2014. https://dc.etsu.edu/etd/2346.

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In order to achieve a more stable and highly proton conducting membrane that is also cost effective, the perfluoroalkyl benzenesulfonylimides (PFSI) polymers are proposed as electrolyte for Proton Exchange Membrane Fuel Cells. 4-(trifluoromethyl)-2-diazonium perfluoro-3, 6-dioxa-4-methyl-7-octene benzenesulfonyl imide (I) is synthesized from Nafion monomer via a 5-step schematic reaction at optimal reaction conditions. This diazonium PFSI zwitterionic monomer can be further subjected to polymerization. The loss of the diazonium N2+ functional group in the monomer is believed to form the covalent bond between the PFSI polymer electrolyte and carbon electrodes support. All the intermediates and final products were characterized using 1H NMR, 19F NMR and IR spectrometry.
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44

Vierke, Lena [Verfasser], and Klaus [Akademischer Betreuer] Kümmerer. "Environmental Mobility of Short Chain Perfluoroalkyl Carboxylic Acids - Partition Behaviour and Resulting Environmental Concern / Lena Vierke. Betreuer: Klaus Kümmerer." Lüneburg : Universitätsbibliothek der Leuphana Universität Lüneburg, 2015. http://d-nb.info/1068361840/34.

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45

Eriksson, Ulrika. "Contribution of polyfluoroalkyl phosphate esters (PAPs) and other precursor compounds to perfluoroalkyl carboxylates (PFCAs) in humans and the environment." Doctoral thesis, Örebro universitet, Institutionen för naturvetenskap och teknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-52010.

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Per-and polyfluoroalkyl substances (PFAS) are anthropogenic compounds that have been spread all over the world. The use of fluorotelomer compounds, short-chained homologues, and other PFASs with perfluorinated moieties has emerged recent years. One of these emerging compound classes is polyfluoroalkyl phosphate esters (PAPs), which have the ability to degrade into persistent PFCAs. The aim of this thesis was to assess the contribution of PAPs and other precursors to the exposure of PFCAs to humans and the environment. The main objective was to analyze a wide range of PFAS in human serum, wild bird eggs, indoor dust, waste water, and sludge. There was a significant contribution from selected precursors to the total amount of PFASs in the abiotic compartments indoor dust, waste water, and sludge. Levels of PAPs found in house dust exceeded those of PFCAs and perfluorosulfonic acids (PFSAs), revealing PAPs as a world-wide important exposure source. A net increase was during waste water treatment was observed for several PFASs in Swedish waste water treatment plants. Together with presence of precursor compounds and intermediates in the influent water and the sludge, this suggest that degradation of PFCA precursors contributed to the increase of PFCAs. Detection of precursors in human serum, together with slow declining trends of PFCAs, revealed an ongoing exposure of PFCAs to the general population of Australia. The diPAPs and the FTSAs were also detected in raptor bird eggs from Sweden from both the terrestrial and the freshwater environment. The precursors concentrations and patterns observed reveal that current regulatory measures are insufficient for the purpose of protecting humans and the environment from PFASs exposure.
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46

Farabegoli, Federica <1986&gt. "Analysis of Perfluoroalkyl Substances and Glycine Betaine: Contribution to the Assessment of Health Risks and Benefits of Seafood Consumption." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amsdottorato.unibo.it/7573/.

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Seafood is known for its valuable and healthy nutrients; however scientific studies demonstrated the unavoidable presence of contaminants in fish and shellfish. Authorities strongly recommend fish consumption, especially to sensible groups of population (pregnant or nursing women, infants and children), and ask the scientific community for novel and coherent data to establish clear guidelines for consumers. There is also a serious need to extend the monitoring to emerging chemical pollutants, other than methylmercury, dioxins and polychlorinated biphenyls, to better understand the level of seafood contamination. An innovative UHPLC-MS/MS method for the quantification of glycine betaine (GB) in Tapes philippinarum was developed and validated, taking the 2002/657 European Decision as guideline; GB is an endogenous osmolyte abundant in molluscs, and represent a vital methylating agent in humans. Moreover, a previously developed and validated UHPLC-MS/MS method was used to conduct a preliminary monitoring of the presence of the two main perfluorinated contaminants, perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA), in six fish species from Italian markets (Dicentrarchus labrax, Merluccius merluccius, Mugil cephalus, Pleuronectes platessa, Scomber scombrus and Sparus aurata). The daily contribution of seafood to PFOS and PFOA dietary intake in Italian population was calculated and data were compared to the corresponding Tolerable Daily Intakes established by EFSA in 2008. Results revealed that the risk of contamination related to fish consumption is unlikely, but suggested the need to conduct further surveys focused on certain species from different sampling site. Subsequently, a mono-specie monitoring was carried out in 140 farmed and wild subjects of Dicentrarchus labrax, from 14 different locations in the Mediterranean area. The obtained results showed that wild subjects are sensibly more contaminated than farmed ones, and that levels of fish contamination are strongly influenced by their geographical origin and the proximity to polluted areas.
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47

Trevino, Leo. "Les (perfluoroalkyl)alcanes et alcènes : étude du comportement amphiphile dans les systèmes dispersés et applications aux vecteurs d'agents thérapeutiques." Nice, 1993. http://www.theses.fr/1993NICE4700.

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Une famille de (perfluoroalkyl)alcanes et alcènes (structures f(cf2)m(ch2)nh ou f(cf2)mch=ch(ch2)nh ; m=4, 6, 8; n=6, 8, 10, 12) a été synthétisée afin d'étudier une nouvelle approche de stabilisation des émulsions de fluorocarbure à finalité biomédicale. Cette approche consiste en l'addition de ces composés, comme chevilles moléculaires, aux émulsions concentrées en fluorocarbure contenant la lécithine de jaune d'œuf comme tensioactif principal, pour diminuer la tension interfaciale entre la phase fluorocarbure et la phase aqueuse qui conduirait à un système plus stable contre le grossissement des particules. L'addition de ces composés aux émulsions de fluorocarbure conduit à une forte stabilisation contre le vieillissement d’Oswald. Nous avons utilisé le traitement théorique de Lifshitz, Slyozov et Wagner en parallèle avec des données expérimentales afin de monter que la stabilisation apportée par les composes fmhn(e) aux émulsions de fluorocarbure est la somme : 1) d'un effet à l'interface et, 2) d'un effet sur la solubilité de la phase dispersée. Nous avons également mis au point de nouveaux systèmes liposomaux qui résultent de l'incorporation de dérivés fmhn(e) dans la membrane de vésicules faite de phospholipides naturels. Les liposomes (suvs) évalués ont été préparés par dispersion de dmpc et de fmhn(e) (fmhn(e)=f4h10e, f4h12, f6h10e, f8h10e et f6h6e) dans l'eau. La formation de ces nouveaux systèmes a été mise en évidence par la mesure directe (cpv) de f4h10e dans des suvs purifies par centrifugation. Nous avons déterminé que le rapport molaire, f4h10e/dmpc, le plus favorise dans la membrane est 1/1 quel que soit le rapport utilise lors de la préparation (1/1 ou 2/1). Cette capacite des (perfluoroalkyl)alcanes et alcènes de s'incorporer dans la membrane bicouche des liposomes et d'en modifier ainsi les propriétés physicochimiques, leur ouvrent des perspectives prometteuses dans le domaine du transport d'agents thérapeutiques
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48

Maisonet, Mildred, Antonia M. Calafat, Michele Marcus, Jouni J. K. Jaakkola, and Hany Lashen. "Prenatal Exposure to Perfluoroalkyl Acids and Serum Testosterone Concentrations at 15 Years of Age in Female ALSPAC Study Participants." Digital Commons @ East Tennessee State University, 2015. https://dc.etsu.edu/etsu-works/1.

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Background: Exposure to perfluorooctane sulfonic acid (PFOS) or to perfluorooctanoic acid (PFOA) increases mouse and human peroxisome proliferator–activated receptor alpha (PPARα) subtype activity, which influences lipid metabolism. Because cholesterol is the substrate from which testosterone is synthesized, exposure to these substances has the potential to alter testosterone concentrations. Objectives: We explored associations of total testosterone and sex hormone–binding globulin (SHBG) concentrations at age 15 years with prenatal exposures to PFOS, PFOA, perfluorohexane sulfonic acid (PFHxS), and perfluoronanoic acid (PFNA) in females. Methods: Prenatal concentrations of the perfluoroalkyl acids (PFAAs) were measured in serum collected from pregnant mothers at enrollment (1991–1992) in the Avon Longitudinal Study of Parents and Children (ALSPAC). The median gestational age when the maternal blood sample was obtained was 16 weeks (interquartile range, 11–28 weeks). Total testosterone and SHBG concentrations were measured in serum obtained from their daughters at 15 years of age. Associations between prenatal PFAAs concentrations and reproductive outcomes were estimated using linear regression models (n = 72). Results: Adjusted total testosterone concentrations were on average 0.18-nmol/L (95% CI: 0.01, 0.35) higher in daughters with prenatal PFOS in the upper concentration tertile compared with daughters with prenatal PFOS in the lower tertile. Adjusted total testosterone concentrations were also higher in daughters with prenatal concentrations of PFOA (β = 0.24; 95% CI: 0.05, 0.43) and PFHxS (β = 0.18; 95% CI: 0.00, 0.35) in the upper tertile compared with daughters with concentrations in the lower tertile. We did not find evidence of associations between PFNA and total testosterone or between any of the PFAAs and SHBG. Conclusions: Our findings were based on a small study sample and should be interpreted with caution. However, they suggest that prenatal exposure to some PFAAs may alter testosterone concentrations in females.
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49

Ibrahim, Faisal. "Synthesis of Diazonium (Perfluoroalkyl) Arylsulfonimide Monomers from Perfluoro (3-Oxapent-4-ene) Sulfonyl Fluoride for Proton Exchange Membrane Fuel Cell." Digital Commons @ East Tennessee State University, 2016. https://dc.etsu.edu/etd/3034.

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Two diazonium perfluoroalkyl arylsulfonimide (PFSI) zwitterionic monomers, 4-diazonium perfluoro(3-oxapent-4-ene)benzenesulfonimide (I) and 4-(trifluoromethyl)-2-diazonium perfluoro(3-oxapent-4-ene)benzenesulfonimide (II) have been synthesized from perfluoro(3-oxapent-4-ene) sulfonyl fluoride (POPF) for proton exchange membrane fuel cells. PFSI polymers are proposed as new electrolytes due to their better thermal stability, inertness to electrochemical conditions, and lower susceptibility to oxidative degradation and dehydration. For a better integration between the electrode and the electrolyte, the PFSI polymers are expected to be grafted onto the carbon electrode via the diazonium moiety. All the reaction intermediates and the final product were characterized with 1H NMR, 19F NMR and IR spectroscopies.
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50

Nyström, Jennifer. "Determinants of serum perfluoroalkyl acid concentrations in Swedish adolescents and the importance of drinking water as a source of exposure." Thesis, Uppsala universitet, Institutionen för biologisk grundutbildning, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-385153.

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The persistent and toxic perfluoroalkyl acids (PFAAs) are ubiquitously present in the environment and reach humans predominantly via food and drinking water. The aim of the present study was to investigate the effect of low-grade (<10 ng L-1 of single PFAAs) contaminated PFAAs drinking water on serum PFAA concentrations in a representative Swedish adolescent population, and to examine the influence of potential determinants on the variation of the PFAAs serum concentrations. This was done by using multivariate regression analysis on the possible determinants of blood serum PFAA concentrations in 479 Swedish adolescents, 10 to 21 years of age, who had left complete dietary and life style information in 2016-17 in the nation-wide food consumption survey Riksmaten Ungdom. Raw and drinking water samples (DW) from water treatment plants (WTPs) that delivered DW to participants schools were sampled in 2018, analysed for PFAAs, and used for assessing the participants DW PFAA exposure. Maternal education level and maternal birth country, consumption of fish, as well as age and sex were significantly associated with the participants PFAAs serum concentrations. DW concentrations as low as <1 ng L for PFOA and PFHxS, <0.45 ng L-1 for PFNA and <4 ng L-1 for PFOS were significantly associated with increased adolescent serum concentrations of the PFAAs in question, which suggests that low-grade contaminated drinking water is an important exposure route for Swedish adolescents. For risk assessment purposes, it was investigated whether parts of the adolescent population exceeded the serum PFOS and PFOA concentrations corresponding to the current health-based reference intakes as assessed by the European Food Safety Authority (EFSA) and the U.S. Agency for Toxic Substances and Disease Registry (ATSDR). Around 1.7% and 2.7% of participants had PFOS serum concentrations exceeding serum levels used to derive the tolerable daily intake (TDI) (EFSA) and the minimum risk level (MRL) (ATSDR), respectively and a cause for concern was consequently identified. However, the high serum concentrations of participants exceeding the TDI and MRL serum concentrations belong to participants suspected to have been previously exposed to highly contaminated drinking water and not from consuming foods and beverages containing background concentrations of PFAAs.
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