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Distribucija opijatnih alkaloida u mozgu / The distribution of opiate alkaloids in brainĐurendić-Brenesel Maja 01 March 2008 (has links)
<p>U ovoj doktorskoj disertaciji je uspešno izvršeno izolovanje opijatnih alkaloida iz humanih bioloških uzoraka (moždanog tkiva, krvi, urina i žuči) kao i bioloških uzoraka <br />eksperimentalnih životinja (moždanog tkiva i krvi) primenom postupka čvrsto-tečne ekstrakcije (SPE-Solid Phase Extraction). Modifikovan je postupak za kvalitativnu i kvantitativnu GC-MS (Gas Chromatography-Mass Spectrometry) analizu bioloških <br />uzoraka. Utvrđena je distribucija opijatnih alkaloida: morfina, kodeina, acetilkodeina, 6-acetilmorfina i heroina u humanim biološkim uzorcima moždanog tkiva (moždanoj kori, moždanom stablu, amigdali i bazalnim jedrima), pri čemu je najveći sadržaj <br />opijata određen u moždanoj kori i bazalnim jedrima, podjednako kod muških i ženskih osoba. Utvrđena je distribucija opijatnih alkaloida: morfina, kodeina, acetilkodeina, 6-acetilmorfina i heroina u biološkim uzorcima moždanog tkiva (moždanoj kori, moždanom stablu, amigdali i bazalnim jedrima) i krvi eksperimentalnih životinja (pacova), u <br />različitim vremenskim periodima (5, 15, 45 i 120 minuta) od tretiranja životinja heroinom. Najveći sadržaj opijata je određen u moždanoj kori i bazalnim jedrima, podjednako kod mužjaka i ženki pacova ali u različitim vremenskim periodima. U uzorcima krvi je najveći sadržaj opijata određen u istom vremenskom periodu kod životinja oba pola, pri čemu su kod mužjaka određene znatno veće vrednosti koncentracija, što ukazuje na bržudistribuciju opijata iz krvi u mozak kod ženki u odnosu na mužjake pacova. Utvrđeno je da je distribucija opijata u humanom moždanom tkivu kod pripadnika suprotnih polova kao i moždanom tkivu mužjaka i ženki pacova (nakon 120 minuta od tretiranja heroinom), identična. Ispitivanjem uticaja opijata na markere oksidativnog stresa u jetri eksperimentalnih životinja suprotnih polova, utvrđeno je smanjenje aktivnosti enzima: katalaze (CAT), glutation-peroksidaze (GSH- Px), peroksidaze (Px) i ksantin-oksidaze (XOD).</p> / <p>Opiate alkaloids were successfully isolated from human biological samples (brain tissue, blood, urine, and bile) as well as from biological samples of experimental animals (brain tissue and blood) by applying procedure of solid-phase extraction (SPE). A modified procedure was worked out for qualitative and quantitative analysis of biological samples by gas chromatography-mass spectrometry (GC-MS). The distribution of opiate alkaloids:morphine, codeine, acetylcodeine, 6-acetylmorphine, and heroine in human biological samples of brain tissue (cortex, brain stem, amigdala and basal nuclei) was established, showing the highest content of opiates in the cortex and basal nuclei, equal with male and female persons. It was established how the opiatealkaloids: morphine codeine, acetylcodeine, 6-acetylmorphine and heroine are distributed in biological samples of brain tissue (cortex, brain stem, amigdala and basal nuclei) and blood of experimental animals (rats) in different time periods (5, 15, 45 and 120 min) after the animal treatment with heroine. The highest content of opiates was found in the cortex and basal nuclei, equal in the male and female rats, but in different time periods. In blood samples, the highest content of opiates was measured in the same period with animals of both sexes, the concentration in the males being significantly higher, indicating a faster passage of the opiates from blood to brain in the female compared to male rats. Identical distribution of opiates was found in human brain tissue of both male and female subjects as in rats of both sexes (120 min after treatment with heroine). Study of the effect of opiates on the markers of oxidative stress in the liver of tested animals of opposite sexes showed a lowered activity of the following enzymes: catalase (CAT), glutathion-peroxidase (GSH-Px), peroxidase (Px) and xanthine-xidase (XOD).</p>
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Determination of the Halogenated Skeleton Constituents of the Marine Demosponge Ianthella bastaUeberlein, Susanne, Machill, Susanne, Schupp, Peter J., Brunner, Eike 17 July 2017 (has links)
Demosponges of the order Verongida such as Ianthella basta exhibit skeletons containing spongin, a collagenous protein, and chitin. Moreover, Verongida sponges are well known to produce bioactive brominated tyrosine derivatives. We recently demonstrated that brominated compounds do not only occur in the cellular matrix but also in the skeletons of the marine sponges Aplysina cavernicola and I. basta. Further investigations revealed the amino acid composition of the skeletons of A. cavernicola including the presence of several halogenated amino acids. In the present work, we investigated the skeletal amino acid composition of the demosponge I. basta, which belongs to the Ianthellidae family, and compared it with that of A. cavernicola from the Aplysinidae family. Seventeen proteinogenic and five non-proteinogenic amino acids were detected in I. basta. Abundantly occurring amino acids like glycine and hydroxyproline show the similarity of I. basta and A. cavernicola and confirm the collagenous nature of their sponging fibers. We also detected nine halogenated tyrosines as an integral part of I. basta skeletons. Since both sponges contain a broad variety of halogenated amino acids, this seems to be characteristic for Verongida sponges. The observed differences of the amino acid composition confirm that spongin exhibits a certain degree of variability even among the members of the order Verongida.
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Evaluation de la contamination des atmosphères intérieures et extérieures induite par les usages non agricoles de pesticides / Evaluation of indoor and outdoor air contamination resulting from non-agricultural uses of pesticidesRaeppel, Caroline 16 November 2012 (has links)
Dans le but d’évaluer la contamination des atmosphères intérieures et extérieures induite par les usages non agricoles de pesticides, deux approches complémentaires ont été mises en oeuvre : l’utilisation de capteurs passifs de type Tenax TA pour réaliser des prélèvements d’air, et l’utilisation de cheveux employés comme biomarqueurs d’exposition. Des campagnes de mesures ont été menées sur plusieurs sites à la suite de traitements de désherbage ou de désinsectisation ainsi quedans des logements. Les échantillons d’air et de cheveux ont été extraits respectivement par thermodésorption et par extraction solide-liquide, avant d’être analysés en chromatographie gazeuse couplée à la spectrométrie de masse (GC-MS). Une augmentation du niveau de contamination de l’air extérieur et intérieur et l’existence de transferts entre ces deux milieux ont pu être observées après l’application de pesticides. Dans les logements, des pesticides actuellement employés mais aussi des pesticides interdits et persistants ont été détectés. Plusieurs pesticides ont également été détectés dans les cheveux, mais l’exposition humaine à ces derniers n’a pas pu toujours être corrélée à une contamination de l’air. / In order to evaluate indoor and outdoor air contamination resulting from non-agricultural uses of pesticides, two complementary approaches were applied: passive samplers based on Tenax TA used for air sampling and hair used as biomarkers of exposure. Sampling campaigns were conducted on several sites after weeding and pest control treatments as well as in accommodations. Air samples and hair samples were respectively extracted by thermal desorption and solid-liquid extraction prior to their analysis by gas chromatography combined with mass spectrometry (GC-MS). An increase of the indoor and outdoor air contamination levels and the existence of transfers between these two environments could be observed after pesticides applications. In accommodations, pesticides currently used and banned but persistent ones were detected. Several pesticides were also detected in hair samples but human exposure to these pesticides cannot be correlated with air contamination in all cases.
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Évaluation des paramètres nécessaires à la détermination de la Date de Durabilité Minimale (DDM) et de la Période après Ouverture (PAO) des émulsions cosmétiques. / Evaluation of the parameters required for the determination of BBD and PAO of cosmetic emulsions.De vaugelade du breuillac, Segolene 02 May 2018 (has links)
Depuis le 11 juillet 2013, date d’application du Règlement cosmétique (CE) No 1223/2009, les metteurs sur le marché sont dans l’obligation de mentionner sur leurs produits la Date de Durabilité Minimale (DDM), ou si celle-ci excède 30 mois, la Période Après Ouverture (PAO). L’estimation de ces dates n’est pas encadrée réglementairement. Cosmetics Europe, l’Agence nationale de sécurité du médicament et des produits de santé, le Comité scientifique pour la sécurité du consommateur ou encore la Commission Européenne proposent des lignes directrices, mais les conditions d’étude pour la détermination de la DDM et de la PAO restent encore à l’appréciation de la personne responsable de la commercialisation du produit. L’objectif de ce travail était d’étudier les conditions nécessaires à la mise en place d’un protocole de mesure de la stabilité d’émulsions cosmétiques, permettant de déterminer la DDM du produit de manière fiable et rapide. Pour cela, une approche expérimentale sur une émulsion représentative de l’industrie cosmétique a été menée. L’évolution des paramètres organoleptiques, physico-chimiques et microbiologiques a été évaluée, en accéléré (température augmentée) et en temps réel. Une approche statistique a montré que les propriétés sensorielles évoluent différemment en fonction de la température et du matériau dans lequel l’émulsion est stockée. L’établissement d’un modèle de correspondance entre le vieillissement en conditions réelles et en conditions accélérées a pu être proposé pour certains paramètres physico-chimiques. Les études de microbiologie se sont tout d’abord concentrées sur la validation d’une méthode commerciale, alternative au dénombrement des germes aérobies totaux encadré par la norme ISO 21149, pour une application dans le domaine cosmétique. Après validation, la méthode a été utilisée comme un outil simple, rapide et économique pour le suivi de la stabilité microbiologique de l’émulsion de référence. La dégradation des conservateurs et de l’antioxydant présents dans la formule de référence a été suivie par chromatographie en phase gazeuse couplée à la spectrométrie de masse (GC-MS). Ce suivi a permis de mettre en évidence l’effet probable de la lumière sur la dégradation des actifs de l’émulsion. A ces tests ont été associés une stratégie analytique visant à étudier la photostabilité de l’émulsion. Les études ont porté sur deux molécules : l’acide déhydroacétique et l’alpha-tocophérol. La stratégie a permis de caractériser les mécanismes impliqués dans les réactions de photodégradation. La chromatographie en phase gazeuse couplée à la spectrométrie de masse multi-étapes (GC-MSn) et la chromatographie en phase liquide couplée à la spectrométrie de masse haute résolution en tandem (LC-HR-MS/MS) ont été utilisées pour la séparation et l'identification structurale des photoproduits. La détection des photoproduits majoritaires dans l’émulsion de référence, après irradiation UV-visible, montre la possible formation des photoproduits dans une matrice complexe de type émulsion huile/eau. Les résultats des tests de toxicité, in silico et/ou in vitro, ont démontré l’importance de prendre en compte la formation éventuelle de photoproduits dans l’évaluation de la sécurité d’un produit cosmétique. / According to Cosmetic Regulation 1223/2009, implemented in July 2013, the manufacturer must mention the Date of Minimum Durability (DMD), or if DMD exceeds 30 months, the Period After Opening (PAO) on the product packaging. At the present time, no text regulates the procedures applicable to the validation of a DMD or a PAO. Some guidelines are published by Cosmetics Europe, the National Agency for the safety of medicines and health products, the Scientific Committee for consumer safety, or the European Commission; but the evaluation remains at the discretion of the person responsible for marketing the product. In this context, this work proposes recommendations to establish a stability protocol in order to quickly determine the DMD. Experimental approaches on an emulsion representative of the major category in the cosmetics industry have been established. Organoleptic, physicochemical and microbiological stabilities were evaluated. The emulsion stability has been tested in accelerated conditions and in real time. A statistical approach has been proposed to evaluate the product shelf life according to its organoleptic properties. The sensory properties of the cosmetic emulsion changed differently depending on the temperature and the material in which it has been stored. A mathematical correlation between the results of studies under normal and those obtained under accelerated conditions has been proposed for some parameters. A microbiological study focused on the validation of a commercially available method, alternative to total count of aerobic microorganisms, normed by the ISO 21149 for cosmetic application. Once validated, this method has been used as an economical, quick and easy tool to evaluate the microbiological stability of cosmetic emulsions. Gas chromatography coupled with mass spectrometry was used to follow the degradation of antioxidant and preservatives. To take into account the photostability of the emulsion, an analytical strategy was proposed to identify the mechanisms involved in phototransformation reactions. The study focused on two molecules: dehydroacetic acid and alpha-tocopherol. Both gas chromatography coupled with tandem mass spectrometry (GC-MS/MS) and liquid chromatography coupled with ultrahigh resolution mass spectrometry (LC-UHR-MS) were used for the separation and the structural identification of photoproducts. The main photoproducts were detected in the reference emulsion after UV-visible irradiation, thus showing the possible formation of photoproducts in a complex oil/water emulsion. Both in silico and in vitro toxicity tests highlighted the need for taking into account the potential formation of photoproducts in the safety evaluation of a cosmetic product.
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Influence of Potassium on Gasification PerformanceRasol, Hepa January 2016 (has links)
To release energy from chemically stored energy in the biomass was the new investigation in recent years. Utilizing of biomass for this purpose occur in two different ways, directly by burning (combustion) the biomass and indirectly by pyrolysis process which will convert the biomass to three main products, bio- tar, bio- char and synthetic gas. Biomass contains different amount of inorganic compound, especially alkali metals which causes some diverse impacts on combustion, pyrolysis and gasification process such as corrosion, agglomeration and fouling problems. This project aims to investigate the effect of K2CO3 on the pyrolysis and gasification processes of three different types of fuel; wood pellets, forest residue pellets and synthetic waste pellets at three different temperatures, 750 °C, 850 °C and 900 °C respectively. The purpose of this work to study and clarify the influence of K2CO3 on char yield, tar yield and tar compositions and the gasification rate and the reactivity of different fuels char. The pyrolysis process was carried out in a fluidized bed reactor during 2 minutes and the products were tar, char and synthetic gas. In this project interested in char and tar only. Char yield calculated and the results shows the char yield increase with increasing of [K2CO3]. While the tar analysis carried on GC- MS instrument at HB to study the tar yield and compositions. The results showed that potassium carbonate has not so much effect on tar yield and its composition. The last part was gasified the char in TGA with steam and CO2 as oxidizing media to study the influence of [K2CO3] on gasification rate and the reactivity of char samples at different temperatures. The result showed the [K2CO3] has inhibitory effect on gasification rate and the reactivity.
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Multi-platform metabolomics assays to study the responsiveness of the human plasma and lung lavage metabolome / Multi-plattform metabolomik för analys av förändringar hos det humana metabolomet i plasma och lungsköljvätskaKarimpour, Masoumeh January 2016 (has links)
Metabolomics as a field has been used to track changes and perturbations in the human body by investigating metabolite profiles indicating the change of metabolite levels over time and in response to different challenges. In this thesis work, the main focus was on applying multiplatform-metabolomics to study the human metabolome following exposure to perturbations, such as diet (in the form of a challenge meal) and exhaust emissions (air pollution exposure in a controlled setting). The cutting-edge analytical platforms used for this purpose were nuclear magnetic resonance (NMR), as well as gas chromatography (GC) and liquid chromatography (LC) coupled to mass spectrometry (MS). Each platform offered unique characterization features, allowing detection and identification of a specific range of metabolites. The use of multiplatform-metabolomics was found to enhance the metabolome coverage and to provide complementary findings that enabled a better understanding of the biochemical processes reflected by the metabolite profiles. Using non-targeted analysis, a wide range of unknown metabolites in plasma were identified during the postprandial stage after a well-defined challenge meal (in Paper I). In addition, a considerable number of metabolites were detected and identified in lung lavage fluid after biodiesel exhaust exposure compared to filtered air exposure (in Paper II). In parallel, using targeted analysis, both lung lavage and plasma fatty acid metabolites were detected and quantified in response to filtered air and biodiesel exhaust exposure (in Paper III and IV). Data processing of raw data followed by data analysis, using both univariate and multivariate methods, enabled changes occurring in metabolites levels to be screened and investigated. For the initial pilot postprandial study, the aim was to investigate the plasma metabolome response after a well-defined meal during the postprandial stage for two types of diet. It was found that independent of the background diet type, levels of metabolites returned to their baseline levels after three hours. This finding was taken into consideration for the biodiesel exhaust exposures studies, designed to limit the impact of dietary effects. Both targeted and non-targeted approaches resulted in important findings. For instance, different metabolite profiles were detected in bronchial wash (BW) compared to bronchoalveolar lavage (BAL) fluid with mainly NMR and LC-MS. Furthermore, biodiesel exhaust exposure resulted in different metabolite profiles as observed by GC-MS, especially in BAL. In addition, fatty acid metabolites in BW, BAL, and plasma were shown to be responsive to biodiesel exhaust exposure, as measured by a targeted LC-MS/MS protocol. In summary, the new analytical methods developed to investigate the responsiveness of the human plasma and lung lavage metabolome proved to be useful in an analytical perspective, and provided important biological findings. However, further studies are needed to validate these results. / Metabolomik har använts för att spåra förändringar och störningar i kroppens funktioner genom undersökning av metabolit-profiler. I detta avhandlingasarbete har huvudfokus varit på tillämpning av flera olika analytiska plattformar för metabolomikstudier av det mänskliga metabolomet efter exponering för olika kost och avgasutsläpp från biodieselbränsle. De sofistikerade analytiska plattformarna som användes för detta ändamål var kärnmagnetisk resonans (NMR), samt gaskromatografi (GC) och vätskekromatografi (LC) kopplat till masspektrometri (MS). Varje plattform erbjöd unika karakteriseringsmöjligheter med detektion och identifiering av specifika grupper av metaboliter. Användningen av multipattformmetabolomik förbättrade täckningen av metabolomet och genererade kompletterande resultat som möjliggjorde en bättre förståelse av de biokemiska processer som reflekteras av metabolitprofilerna. Med hjälp av breda analyser har ett stort antal okända metaboliter i plasma identifierats under den postprandial fasen efter en väldefinerad måltid (i Paper I). Dessutom har ett stort antal metaboliter påvisats och identifierats i lungsköljvätska efter exponering av biodieselavgaser jämfört med kontollexponering med filtrerad luft (i Paper II). Parallellt med dessa breda analyser har också riktade analyser genomförts av både lungsköljvätska och plasma. Därigenom har bioaktiva lipider detekterats och kvantifieras efter avgasexponering och resultaten har jämförts med filtrerad luft som kontrollexponering (Paper III och IV). Processning av rådata följt av dataanalys, med både univariata och multivariata metoder möjliggjorde screening och fördjupad undersökning av förändringen i metabolitnivåer. I den första pilotstudien av postprandiala nivåer var syftet att undersöka responsen i plasmametabolomet efter en väldefinierad måltid under den postprandiala fasen vid två olika typer av kost. Resultaten visade att oberoende av kosten, så återvände metabolitnivåerna till sina baslinjenivåer tre timmar efter måltiden. Detta togs i beaktande vid exponeringsstudierna för biodieselavgaser, som designades så att dietens inverkan minimerades. Både breda och riktade analyser resulterade i viktiga resultat. Exempelvis så detekterades olika metabolitprofiler i bronkiell sköljvätska (BW) jämfört med bronkoalveolär sköljvätska (BAL), speciellt med NMR och LC-MS. Dessutom resulterade avgasexponering i förändrade metabolitprofiler, observerade med GC-MS, särskilt i BAL. Dessutom uppvisade fettsyrametaboliter i BW, BAL och plasma förändrade halter efter avgasexponering, uppmätt genom en riktad LC-MS/MS-analys. Sammanfattningsvis så visade sig de nya metoderna som utvecklats för att undersöka förändringar i metabolithalterna i plasma och lungsköljvätska fungera väl ur ett analytiskt perspektiv och resulterade i viktiga biologiska fynd. Fördjupade studier behövs dock för att validera resultaten.
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Buttering up the dead : An archaeological study of the relationship between burial urns and grave gifts from the scandinavian Roman Iron Age from Uppland, Sweden, using lipid-and elemental analysesSundström, Annika January 2016 (has links)
Denna uppsats undersöker begravningsurnor som deponerats under romersk järnålder i grav A7000 i Broby bro, Täby Socken, Sverige. Materialet som undersöks är en del av forskningsprojektet; Broby bro – en plats där världen passerar. Teorierna kring begravningsritualer från denna tidsperiod har genom lipidanalyser samt elementanalyser förfinats. Av de fem kärl som undersöks har fyra, F16007, F16152, F16195 och F16263, definierats som begravningsurnor. F16137 är fortfarande oidentifierad. Fokus har lagts på att undersöka relationen mellan fynden och även att fastställa om F16195 och F16263 kommer från samma urna. Resultaten visar att F16195 är en gravgåva till F16263.
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Undersökning av avgasemissioner till vatten från dieselinombordsmotorer i fritidsbåtar : En jämförande studie av olika bränslenÖstman, Ninnie January 2006 (has links)
<p>In this Masters Thesis emissions to water from diesel engines in pleasure boats when driven with alternative fuels have been investigated. Two alternative fuels, Fischer-Tropsch-diesel (FT-diesel) and a blend of FT-diesel and rapeseed methyl ester (RME) have been compared with diesel of Swedish environmental class 1 (diesel EC1). The alternative fuels have been compared using two older marine diesel engines, and water samples have been taken from the water in the exhaust system before the exhaust compounds reaches the recipient. The water samples have been analysed with gas chromatography (GC) and mass spectrometry (GC/MS), to analyse volatile and semi volatile compounds including aldehydes and ketons. To investigate the acute toxicity of the exhaust water a 24 h ecotoxicological test was preformed with the crustacean Artemia fransiscana.</p><p>The results showed considerable differences in emissions of poly aromatic hydrocarbons (PAHs) and alkylated benzenes. From diesel EC1, the amounts of PAHs and alkylated benzenes were significantly higher than from pure FT-diesel and FT-diesel containing 20 % of RME. Pure FT-diesel generated the lowest amounts of PAH and alkylated benzenes. The FT-diesel containing 20 % RME generated higher amounts of benzene than diesel EC1. FT-diesel and FT-diesel with a 20 % blend of RME generated the same amount of acetone, which in turn was higher than the concentration of acetone in the exhaust water, using diesel EC1. Based on the analysis, FT-diesel is the best alternative from an exhaust emission point-of-view, concerning both the amounts and the difference in chemical composition of the combustion products released into the water.</p><p>The ecotoxicological test showed no effect on the test organism using either of the samples.</p> / <p>Fritidsbåtsintresset är stort i Sverige och båtlivet betyder mycket för många svenskar. Tyvärr är användningen av fritidsbåtar förknippad med en rad miljöproblem. Avgasutsläpp till vatten och luft från fritidsbåtsmotorer påverkar den lokala miljön avsevärt. Gammal teknik med dålig förbränning används fortfarande i stor utsträckning. På kort sikt, innan den gamla tekniken är utbytt, är det viktigt att den äldre motorparken använder miljöanpassade bränslen för att utsläppen till sjöar och hav ska bli så skonsamma som möjligt. Det är dock viktigt att utvärdera miljöpåverkan av dessa alternativa bränslen, så att det verkligen är ett bättre alternativ ur miljösynpunkt.</p><p>I detta examensarbete har utsläpp till vatten från dieselinombordsmotorer vid drift med olika bränslen undersökts. Två miljöanpassade dieselbränslen; FT-diesel (Fischer-Tropsch) och en procentinblandning av rapsmetylester (RME) i FT-diesel, har jämförts med diesel av svensk miljöklass 1 (MK1). Bränslena har testkörts i två äldre, marina dieselmotorer och prover har tagits på det avgasblandade kylvattnet innan det når recipienten. Det avgasblandade kylvattnet har analyserats med avseende på delvis flyktiga och flyktiga föreningar, aldehyder samt ketoner. Analyserna har skett med gaskromatografi och masspektormetri (GC/MS-screening) på externt laboratorium. För att testa avgasvattnets akuta giftighet har även ett akut (24h) ekotoxikologiskt test utförts på kräftdjuret Artemia fransiscana.</p><p>Analysresultatet visade skillnad i utsläpp av polyaromatiska kolväten (PAH) och alkylbensener. Vid körning med diesel MK1 genererades betydligt högre halter av PAH:er och alkylbensener, än vid körning med FT-diesel och FT-diesel med 20 % inblandning av RME. Ren FT-diesel gav de lägsta halterna av PAH:er och alkylbensener.</p><p>Utsläppshalterna av bensen uppvisade inte lika stor skillnad mellan de olika bränslena. Blandningen FT-diesel med 20 % RME gav lite högre halter bensen än vad diesel MK1 gjorde. Ren FT-diesel uppvisade lägst halt bensen. Utsläpp av aceton visade sig vara lika för FT-diesel och FT-diesel med 20 % RME och gav högre halter än vad diesel MK1 gjorde. Baserat på analysresultaten är FT-diesel det bästa bränslet ur emissionssynpunkt med avseende på vilka ämnen som hamnar i vattenfasen.</p><p>Det ekotoxikologiska testet visade ingen skillnad mellan de olika bränslena. Avgasvatten från bränslena hade inte någon akut toxisk effekt på testdjuret.</p>
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Chemical and bioanalytical characterisation of PAH-contaminated soils : identification, availability and mixture toxicity of AhR agonistsLarsson, Maria January 2013 (has links)
Contaminated soils are a worldwide problem. Polycyclic aromatic hydrocarbons (PAHs) are common contaminants in soil at former industrial areas, especially at old gasworks sites, gas stations and former wood impregnation facilities. Risk assessments of PAHs in contaminated soils are usually based on chemical analysis of a small number of individual PAHs, which only constitute a small part of the complex cocktail of hundreds of PAHs and other related polycyclic aromatic compounds (PACs) in the soils. Generally, the mixture composition of PAH-contaminated soils is rarely known and the mechanisms of toxicity and interactions between the pollutants are far from fully understood. The main objective of this thesis was to characterize remediated PAHcontaminated soils by use of a chemical and bioanalytical approach. Bioassay specific relative potency (REP) values for 38 PAHs and related PACs were developed in the sensitive H4IIE-luc bioassay and used in massbalance analysis of remediated PAH contaminated soils, to assess the contribution of chemically quantified compounds to the overall aryl hydrocarbon receptor (AhR)-mediated activity observed in the H4IIE-luc bioassay. Mixtures studies showed additive AhR-mediated effects of PACs, including PAHs, oxy PAHs, methylated PAHs and azaarenes, in the bioassay, which supports the use of REP values in risk assessment. The results from the chemical and bioassay analysis showed that PAH-contaminated soils contained a large fraction of AhR activating compounds whose effect could not be explained by chemical analysis of the 16 priority PAHs. Further chemical identification and biological studies are necessary to determine whether these unknown substances pose a risk to human health or the environment. Results presented in this thesis are an important step in the development of AhR-based bioassay analysis and risk assessment of complex PAH-contaminated samples. / <p>Other funders: Sparbanksstiftelsen Nya and Ångpanneföreningen</p>
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Etude des phénomènes de biotransformation des hydrocarbures aromatiques polycycliques (HAP) par les organismes aquatiques (poissons) : relation exposition - génotoxicitéLe Dû-Lacoste, Marie 12 December 2008 (has links)
Afin d’étudier la santé d’un écosystème marin et le potentiel toxique d’une contamination telle que celle liée à la présence d’hydrocarbures aromatiques polycycliques (HAP), il est nécessaire, outre de connaître les niveaux de contamination du milieu, de pouvoir accéder à la fraction toxique à laquelle les organismes aquatiques ont été exposés et de connaître les effets toxiques des contaminants incriminés. L’exposition et la contamination des organismes aquatiques aux HAP ont généralement été évaluées par le dosage des HAP bioaccumulés dans les tissus. Or, cette approche est critiquable si l'on tient compte des capacités de biotransformation des organismes, notamment des vertébrés, et des propriétés toxiques des produits de transformation formés. Dans ce contexte, l’objectif de cette thèse est d’étudier les phénomènes de bioccumulation et de biotransformation des HAP chez les organismes marins via l’étude des métabolites de HAP. Un effort de validation de biomarqueurs pertinents pour évaluer la génotoxicité des HAP en lien avec la contamination chimique des tissus et la production de métabolites est nécessaire. Des méthodes de dosage des métabolites de HAP dans les matrices biologiques ont tout d’abord été mises au point. Ces outils analytiques sensibles, innovants et performants ont ensuite été appliqués lors d’expositions de poissons à des HAP via différentes voies de contamination en milieu contrôlé. Ils ont permis une meilleure connaissance des phénomènes de biotransformation des HAP. Enfin, des études de terrain ont été réalisées, notamment dans le cadre de l’étude de la contamination de la Baie de Seine, montrant l’applicabilité du dosage des métabolites de HAP dans l’évaluation de l’exposition des organismes aux HAP en milieu naturel. Dans le cadre d’une approche intégrée chimie/biologie, ces travaux ont permis d’apporter une contribution dans le transfert méthodologique des biomarqueurs de génotoxicité des HAP pour des applications en surveillance de l’Atlantique Nord et notamment dans la Manche. / In order to study the health of a marine ecosystem and the toxic potential of a contamination such as that related to the presence of polycyclic aromatic hydrocarbons (PAHs), it is necessary, in addition to the determination of environmental contamination levels, to have access to the fraction for aquatic organisms have been exposed to and to identify the toxic effects of the contaminants. The exposure and contamination of aquatic organisms to PAHs have generally been evaluated by the quantification of bioaccumulated PAHs in tissues. However, this approach is criticable when taking into account the biotransformation capabilities of organisms such as vertebrates and the toxic properties of biotransformation products. In this way, the aim of this study is to study PAH bioaccumulation and biotransformation phenomena through the PAH metabolites study. An effort for the validation of relevant biomarkers to evaluate the link between the genotoxicity of PAHs, PAHs body burden and PAH metabolites production, is necessary. Analytical techniques to quantify PAH metabolites in biological matrices have first been set up. Then, these sensible, innovating and powerful analytical tools have been applied to the study of fish exposures to PAHs through differents contamination sources in controlled conditions. This allowed to have a better understanding of PAH biotransformation phenomena. Finally, field studies have been led, notably to study the contamination of the Seine bay, demonstrating the applicability of the quantification of PAH metabolites to evaluate the exposure and the contamination of organisms to PAHs in natural environment. Within the framework of an integrated approach chemistry/biology, this work led to a contribution in the methodological transfer of biomarkers of PAH genotoxicity
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