The current treatment of water contaminated with organic compounds includes adsorption, air stripping, and advanced oxidation processes. These methods large quantities of water and require excessive energy and time. A novel treatment process of concentrating and then electrochemically oxidizing compound would be a more feasible practice. This research investigated the oxidative destruction of perfluorooctane sulfonate (PFOS), perfluorobutane sulfonate (PFBS) and trichloroethene (TCE) at boron-doped diamond film electrodes and the adsorption of PFOS and PFBS on granular activated carbon and ion exchange resins.Experiments measuring oxidation rates of PFOS and PFBS were performed over a range in current densities and temperatures using a rotating disk electrode (RDE) reactor and a parallel plate flow-through reactor. Oxidation of PFOS was rapid and yielded sulfate, fluoride, carbon dioxide and trace levels of trifluoroacetic acid. Oxidation of PFBS was slower than that of PFOS. A comparison of the experimentally measured apparent activation energy with those calculated using Density Functional Theory (DFT) studies indicated that the most likely rate-limiting step for PFOS and PFBS oxidation was direct electron transfer. The costs for treating PFOS and PFBS solutions were compared and showed that PFOS is cheaper to degrade than PFBS.Screening studies were performed to find a viable adsorbent or ion exchange resin for concentrating PFOS or PFBS. Granular activated carbon F400 (GAC-F400) and an ion exchange resin, Amberlite IRA-458, were the best methods for adsorbing PFOS. Ionic strength experiments showed that the solubility of the compounds affected the adsorption onto solid phases. Regeneration experiments were carried out to determine the best method of recovering these compounds from the adsorbents; however, the compounds could not be effectively removed from the adsorbents using standard techniques.The electrochemical oxidation of trichloroethene (TCE) at boron-doped diamond film electrodes was studied to determine if this would be a viable degradation method for chlorinated solvents. Flow-through experiments were performed and showed TCE oxidation to be very rapid. Comparing the data from the DFT studies and the experimentally calculated apparent activation energies the mechanism for TCE oxidation was determined to be controlled by both direct electron transfer and oxidation via hydroxyl radicals.

El sulfonato de perfluorooctano (PFOS) es un compuesto orgánico ampliamente utilizado en la industria como agente surfactante. Varios estudios ambientales han mostrado que el PFOS es un contaminante global, persistente y bioacumulativo, cuyos niveles en la población y en el medio ambiente son en la actualidad un riesgo potencial. Sin embargo, los efectos tóxicos del PFOS no han sido aún bien caracterizados. Se considera que este compuesto es un posible disruptor endocrino con efectos sobre los niveles de hormonas tiroideas y glucocorticoides. Por otra parte, se ha demostrado que el estrés materno produce efectos adversos sobre la madre y el desarrollo pre y postnatal de la descendencia, estos incluyen alteraciones en el aprendizaje en machos y alteraciones en el comportamiento en respuesta a situaciones estresantes. No obstante, el patrón de efectos derivados de la exposición a estrés durante la gestación depende del periodo de exposición y el tipo/intensidad del estresor. Son varias las investigaciones que demuestran que algunas sustancias químicas pueden modular los efectos del estrés materno, y a la inversa, el estrés materno puede modificar los efectos de ciertas sustancias químicas, en especial cuando estas se administran a dosis relativamente elevadas. Por lo tanto, el estrés y el PFOS podrían compartir mecanismos de acción comunes, lo que podría incrementar el riesgo de interacciones toxicológicas entre estos dos factores. El objetivo de la presente tesis es evaluar los efectos del PFOS, del estrés prenatal y de una posible interacción entre ambos factores sobre la toxicidad materna, el desarrollo pre y postnatal y la conducta de la descendencia, además de valorar la conducta en sujetos adultos tras la exposición a PFOS. Se utilizaron ratones albinos, cepa CD1. Con el objetivo de determinar la toxicidad materna y embriofetal, se administró 0, 1.5, 3 ó 6 mg/kg/día de PFOS vía oral (Días de Gestación 6-18) a hembras que mostraron presencia de tapón vaginal. La mitad de animales de cada grupo fue expuesta a estrés por inmovilización 30 minutos, 3 veces al día. Con el objetivo de determinar la toxicidad sobre el desarrollo postnatal y el comportamiento a largo plazo, se administró vía oral 0 ó 6 mg/kg/día a hembras con tapón vaginal durante los DG 12-18. La mitad de animales de cada grupo fue sujeta, a la vez, a estrés por inmovilización durante 30 minutos, 3 veces al día, durante el mismo periodo.Con el objetivo de determinar los efectos del PFOS sobre el comportamiento en la edad adulta, se administró 0, 3 ó 6 mg/kg/día de PFOS vía oral a ratones machos adultos durante 4 semanas consecutivas. Los resultados de la presente tesis muestran que la exposición a PFOS y a estrés por inmovilización produce efectos maternotóxicos. No existen efectos de potenciación entre estos dos factores sobre la toxicidad materna. Se observó que el PFOS aumenta la mortalidad prenatal. El estrés materno, a su vez, incrementó la mortalidad prenatal en el grupo expuesto a la dosis de PFOS más baja. La exposición simultánea a PFOS y estrés por inmovilización durante la gestación produce efectos opuestos sobre el desarrollo postnatal de la descendencia. Estos efectos consisiten en una tendencia hacia un retraso general en la maduración, por parte del PFOS, y un patrón de maduración general acelerada, por parte del estrés prenatal. A pesar de que la interacción entre la administración de PFOS y estrés prenatal no causó efectos adversos sobre la maduración física o el desarrollo neuromotor, esta causó alteraciones en el comportamiento en la edad adulta. El efecto más remarcable, producido tras la administración de PFOS a ratones adultos, fue el deterioro en la retención de una tarea espacial. / Perfluorooctane sulfonate (PFOS) is a persistent and bioaccumulative pollutant that can be released from several fluorochemicals by. The surfactant properties of this chemical have made it desirable for extensive use in industrial and commercial applications including surface protection, paper and food- package treatment, and lubricants. A number of recent studies have shown the presence of PFOS in blood samples from occupationally and non-occupationally exposed humans. Studies focused on the developmental effects of oral PFOS during pregnancy have shown dose-dependent adverse effects in rodents. Maternal and developmental toxicity were observed as reductions in maternal weight gain, reductions in fetal body weight, and delays in developmental landmarks and neuromotor maturation. Prenatal and postnatal mortality have been also reported. The toxicological profile of PFOS in adult rodents shows a significant weight loss accompanied by hepatotoxicity and reduced levels of serum cholesterol and triglycerides. However, the potential toxicity of PFOS has not been completely characterized yet. On the other hand, it has been established that gestational stress during a critical period of the embryonic development may modify gestational parameters and produce longlasting alterations in the behavior of the offspring. The presence and persistence of such adverse effects depend on factors such as the exact timing of exposure to stress of the dam and the type and intensity of stressor.It has been reported that some chemicals can alter the effects of maternal stress and, conversely, maternal stress can modify the potential adverse effects of some contaminants, in particular when they have been administered at high doses. The purpose of the present study was to evaluate whether maternal stress can modify the potential adverse effects of prenatal oral exposure to PFOS in mice.In order to assess the maternal and developmental toxicity of combined exposure to restraint stress and perfluorooctane sulfonate in mice, four groups of plug-positive female mice were orally exposed to PFOS at 0, 1.5, 3 and 6 mg/kg/day during gestation days 6-18. Four additional groups of plug-positive animals received the same PFOS doses being restrained during 30 min three times per day. Cesarean sections were performed on Day 18 of gestation and fetuses were weighed and examined for external, internal and skeletal malformations and variations. Before sacrifice of the dams, blood was collected and serum samples were prepared for thyroid hormones (total and free T3 and T4) and corticosterone analyses. In order to assess the combined effects of maternal restraint stress and (PFOS) on postnatal development and behavior of the offspring, thirty-four plug positive females were randomly divided into two groups. Animals were given by gavage 0 and 6 mg PFOS/kg/day on gestation days 12-18. One-half of the animals in each group was subjected to restraint stress (30 min per session, three sessions per day) during the same period. At 3 months of age, the offspring was evaluated for general activity in an open-field, and for learning and memory in a water maze task. After behavioral testing, serum was collected for corticosterone analyses. In order to assess the behavioral effects of PFOS on adult mice, thirty adult mice were divided into three groups. Animals were given by gavage 0, 3, and 6 mg PFOS/kg/day for four consecutive weeks. After the treatment period, mice were evaluated for several skills by testing motor and sensory function by means of a functional observation battery (FOB), general activity and exploratory behavior in an open-field, and learning and memory in a water maze task. One week after behavioral testing, serum was collected for corticosterone analyses. The results of the present study show that both PFOS and restraint stress induced maternal toxicity. PFOS-induced adverse effects on maternal and fetal toxicity in mice were observed at lower doses than those previously reported. Pups of dams exposed to 6 mg/kg of PFOS showed a reduced body weight. Moreover, PFOS exposure induced some delay in developmental landmarks and neuromotor maturation. The current results indicate that concurrent exposure to PFOS and restraint stress during pregnancy induces opposite effects on developmental parameters in the pups. These effects consist in a general delayed maturation trend induced by PFOS exposure, and a general accelerated maturation pattern induced by prenatal stress. Our results suggest interactive deleterious effects between PFOS and maternal stress on the behaviour of the offspring. Our results indicate that PFOS exposure induced only slight behavioral effects in adult male mice. In the retention test, a deleterious effect of PFOS was noted.

Submitted by Gisele Mara Hadlich (gisele@ufba.br) on 2018-06-05T14:52:20Z No. of bitstreams: 1 DISSERTA_RodrigoNascimento_Final_Impressão.pdf: 800294 bytes, checksum: e02922d9fe7dba97a4b7c3225ecc9a68 (MD5) / Made available in DSpace on 2018-06-05T14:52:20Z (GMT). No. of bitstreams: 1 DISSERTA_RodrigoNascimento_Final_Impressão.pdf: 800294 bytes, checksum: e02922d9fe7dba97a4b7c3225ecc9a68 (MD5) / A sulfluramida (N-etil perfluorooctano sulfonamida, EtFOSA) tem sido largamente utilizada no Brasil como princípio ativo em iscas formicidas na atividade agrícola. Essa substância é precursora doácido perfluorooctano sulfônico (PFOS), perfluorooctano sulfonamida (FOSA) e do ácido perfluorooctanóico (PFOA) para o meio ambiente. Em 2009, o PFOS foi inserido na Convenção de Estocolmo sobre poluentes orgânicos persistentes. Recentemente, elevadas concentrações de PFOS foram verificadas na costa do Brasil. Portanto, o presente estudo teve como objetivo avaliar se o uso da sulfluramida pela atividade agrícola é uma fonte do PFOS e outros PFASs para a zona costeira. Para isso, a região Extremo Sul do Estado da Bahia, Brasil, foi utilizada como estudo de caso, tendo em vista as extensas plantações de eucalipto nessa área. Foram coletas amostras pareadas de água esedimento superficiais da plataforma continental em direção ao estuário de Caravelas (estações S1 à S10). Adicionalmente foram coletadasamostras de água superficial estuarina (A1), fluvial (A2 à A5) e subterrânea (A6), ao longo do rio Itanhém. Os compostos alvo foram extraídos em fase sólida e determinados por cromatografia líquida de ultra performance acoplada a um duplo espectrômetro de massa (UPLC-MS-MS). O somatório de PFASs (∑PFASs) em água e sedimento das amostras S1 à S10 variaram entre <LDM à 1015 pg L-1 e <LDM à 198 pg g-1, respectivamente.PFOS e o FOSA foram as únicas substâncias detectados em água, enquanto em sedimento, o PFOA também esteve presente na maioria das amostras. Esses compostospodem ser resultantes da degradação da sulfluramida, dando suporte a hipótese de que o uso dessa substância é uma fonte de PFASs para o ambiente costeiro.As amostras coletadas ao longo do rio Itanhém exibiram maiores concentrações de PFASs (∑PFASs entre 572 e 9846 pg L-1) quando comparadas às amostras estuarinas e marinhas, sugerindo o efeito da diluição nestas últimas.PFOS e PFOA foram detectados em todas as amostras, enquanto o FOSA foi detectado somente em A1 e A5.PFOS e PFOA também foram detectadosnaamostra de água subterrânea.Adicionalmente foram detectados o ácido perfluorohexanóico(PFHxA) e o ácido perfluorobutanóico (PFBA).A presença do PFHxA pode estar relacionada a impurezas nas iscas formicidas. Por outro lado, as elevadas concentrações de PFBA alertam para outras fontes de PFASs, além da sulfluramida. O coeficiente de partição sedimento-água para o PFOS e o FOSA mostrou que o sedimento marinho é um importante sumidouro desses compostos.

Per- and polyfluorinated alkyl substances (PFASs) belong to a large group of man-made chemicals that pollute the environment. Perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) are the most commonly found PFASs. The pollution of PFASs can be caused among others by using of aqueous fire-fighting foams (AFFFs). PFASs are persistent compounds; that can travel long distances and bioaccumulate in biota. There are several exposure routes for PFASs, but the most common are via food and drinking water. A possible way for PFASs to enter the food chain is by adsorption to microbes. In this project, binding of PFASs to three gram-negative bacteria, Eschericha coli, Acidovorax delafieldii and Pseudomonas nitroreducens, was assessed. Microbes were exposed for fluorinated compounds in environmental water samples and a PFAS-11 solution with 11 PFAS substances prepared in the laboratory. The binding seems to be preferential to the most abundant compounds, PFOS, since the second most abundant compound in the samples was PFHxS with concentrations at one third of the PFOS concentration but nonetheless PFHxS was not detected in any of the samples. The binding of mainly one PFAS was identified; PFOS was bound at highest concentrations in E. coli treated with both environmental water sample and a PFAS-11 solution. Low concentrations of FOSA and PFDoDS were identified in E. coli and PFNA in A. delafieldii. Only PFOS was detected in P. nitroreducens. The concentrations of other PFASs were below their respective method detection limits.

PFAS are a group of relatively newly discovered man-made pollutants. PFAS contains a C-F bond which is one of the strongest bonds in organic chemistry. Therefore, PFAS are not easily degradable and, once release into nature, are very persistent. PFAS are also labile in natural environments and therefore, they can sometimes be found far from the source of pollution. Their persistent and labile nature, in combination with their bioaccumulation ability and human health effects make of this compounds an important contaminant to take care of. Currently there are not stablish, wellfunctioning methods to treat contaminated soils and waters. A lot of research is performed at the moment to find good treatment options. In this work a test to chemically degraded spiked samples of PFOA, PFOS and PFBA was performed. By means of experimental design tools, we aim to evaluate which operational factors are relevant for this treatment. Best results when using hydrogen peroxide as a reactant was 70% degradation for PFOS and 42% degradation for PFOA. When persulfate was used as a reactant, a 57% degradation of PFOS, 99% degradation of PFOA and 99% degradation of PFBA was achieved.

Perfluorinated compounds (PFCs) are considered as persistent organic pollutants. Their extensive use in various products leads to increase of their occurence in surface and ground water, soil, air and, generally, in the global ecosystem. In this diploma thesis, method for detection and quantification of 19 perfluorinated compounds was developed. This method was used for analysis of real drinking water and sewage sludge samples from Czech Republic. It is based on pre-extraction step and consecutive liquid chromatography with mass spectrometry, using negative chemical ionization (LC-MS). We developed a method for analysis of water samples, using solid-phase extraction (SPE). Using this method, concentrations of PFCs in 8 samples of drinking water from Czech Republic were evaluated. Total concentration of analyzed PFCs was 4 - 23 ng/L. Processing of sewage sludge samples using accelerated solvent extraction (ASE) showed matrix effect, which influenced ionization and led to false positive/negative results. For supression of the matrix compounds, we used SPE Envi-Carb columns. Using this optimised method, 23 sewage sludge samples from different locations in Czech Republic were analyzed. The most represented PFC in the environment, perfluoroctane sulfonate (PFOS), was detected in concentrations 5 - 386...

At Bromma Stockholm Airport, fire drills have previously been performed at a location outside the current airport confinements. Fire drills were performed with extinguisher foams containing toxic perfluorooctanesulfonic acid (PFOS), which have polluted the site. Harmful effects of PFOS include but are not limited to damages to the endocrine system. The contaminant is relatively soluble and can be transported by water. The aim of this thesis was to model groundwater flows and PFOS transport in the area. In order to build the model, data was gathered from databases, literature studies and field investigations. The field investigations included geophysical measurements. The model was built in the software Visual MODFLOW Classic. It was used to increase knowledge of hydrogeological conditions in the area, predict the fate of PFOS leaching from the site and suggest preventative measures for preventing the spread. The model results showed that the contaminant is transported towards the current airport area by means of groundwater at a slow rate and with low concentrations. Additionally, high concentrations of PFOS will remain in soil and groundwater at the study area for several hundreds of years, according to model results. Preventative measures should therefore be focused on minimizing risks to frequent visitors to the site, which is currently used as a golf course.

Effective adsorbents for polyfluorinated compounds (PFCs) were obtained and successfully tested in adsorption of perfluorooctanoic and perfluorooctanesulfonic acids. Bridged silsesquioxanes containing secondary and tertiary amino groups were synthesized by sol-gel condensation of bis[3-(trimethoxysilyl)propyl]amine and N-methyl-3,3′-bis(trimethoxysilyl)dipropylamine in acidic media in the presence of surfactants. Obtained materials were mesoporous with high BET surface area. They combine high structural stability with high concentration of surface amino groups serving as adsorption sites. Batch adsorption tests demonstrated their high adsorption capacity on PFCs: in some experiments it reached up to 88% of the adsorbent weight. Adsorption of PFCs changed the surfaces of the adsorbent nanoparticles from hydrophilic to hydrophobic thus providing their agglomeration and floatability. Column tests showed fast adsorption of PFCs even at high concentrations and high flow rates. Obtained results can be used in the development of an effective filtration device for clean-up of water contaminated by PFCs.

No description available.

Per- and polyfluoroalkyl substances, PFASs, are highly fluorinated substances where the carbon chain is fully- or partly fluorinated. A functional group is coupled at the end of the carbon chain which gives PFASs their different properties. PFASs have been used in aqueous film forming foams (AFFFs) to decrease the surface tension of water and form a film on the fuel surfaces. AFFF is one of the main sources of PFASs pollution in the environment. A previous study has shown high PFASs concentrations in surface water in Lake Vänern. This study has analysed PFASs in sediment samples. The main detected PFASs was perfluorooctane sulfonate, PFOS, with concentrations below limit of detection to 51700 pg/g wet weight (ww). The compound detected in the highest concentration in Vissbäcken was PFOS at 7290 pg/g ww, this was followed by 6:2 fluorotelomersulfonate , 6:2FTS, at 516 pg/g ww. In outlet 4 (utlopp 4), PFOS had the highest concentration at 51800 pg/g ww, followed by perfluorohexane sulfonate, PFHxS, at 1790 pg/g ww. The only detected compound in the sediment cores was PFOS with approximately 100 pg/g ww. The high concentration of PFOS might be due to extensive use with subsequent release of firefighting foam in the area and degradation of other PFAS substances into PFOS. / Per-och polyfluoroalkylsubstanser, PFASs, är en grupp högfluorerade ämnen där kolkedjan är helt eller delvis fluorerad. En funktionell grupp kopplas i slutet av kolkedjan vilket ger PFASs dess olika egenskaper. PFAS har använts i vattenhaltiga filmbildande skum (AFFF) för att minska ytspänningen av vatten och bilda en film på bränsleytan. AFFF är en av huvudkällorna för PFAS-föroreningar i miljön. En tidigare studie har visat på höga koncentrationer av PFASs i ytvatten i Vänern. I denna studie har PFASs analyserats i sedimentprover. Den huvudsakliga detekterade PFAS var perfluoroktansulfonat, PFOS, med koncentrationer under detektionsgränsen och till 51700 pg /g våtvikt. Den högst detekterade föreningen i Vissbäcken var PFOS med 7290 pg/g våtvikt, detta följdes av 6:2 fluorotelomersulfonat, 6:2 FTS, med 516 pg/g våtvikt. Den högst detekterade föreningen i utlopp 4 var PFOS med 51800 pg/g våtvikt, följt av perfluorhexansulfonat, PFHxS, med 1790 pg /g våtvikt. Den enda detekterade föreningen i sedimentpropparna var PFOS med ungefär 100 pg/g våtvikt. Förekomsten av PFOS i sediment i sjön Vänern kan bero på omfattande användning med efterföljande utsläpp av brandbekämpningsskum i området och nedbrytning av andra PFAS-substanser till PFOS.