In the reservoir conditions, a petroleum fluid is defined by its thermodynamic and volumetric properties and by its physicochemical properties. Their behaviors are modeled from experimental data in order to properly simulate the processing of these fluids during the production.   With the advent of new regulations and rigidity that exist at the custom regulations today, research centers have great difficulty in obtaining large amounts of samples. For these reason, although there are several methods to characterize the different components of crude oil, the laboratories are turning increasingly to techniques that requires lower amounts of samples: micro-distillation, gas chromatography (GC).   The micro-distillation is a fast and completely computerized technique made to substitute the standard distillation for analysis of liquid petroleum products. Advantages of the method compared to the standard distillation are the reduction of working time by at least a factor of 4, the small sample volumes required for distillation (few micro liters). [24]   This report is aimed to create a simple model that can predict yield curves of physical distillation, without using the micro-distillation technique. The results obtained through gas chromatography (GC) analysis by laboratory technicians enable the modeling of the fluid behavior. Having identified and treated practically all aspects of micro-distillation through simulations with PRO/II, I found out that, regardless of the setting and the thermodynamic method used, there are always significant differences between simulation results and those of the micro-distillation.   The result shows that it’s still difficult to create a model which can replace micro-distillation and gas chromatography (GC) because of the huge gap between the simulation results and micro-distillation. Furthermore, the dynamics revealed that the micro distillation is not accurate. I had hoped to get additional results by studies the correlations with more samples, but that did not turn out to be the case. Regardless of that, I think that it would be interesting to study more samples and use another simulator to properly represent micro distillation. This could be an interesting topic for further studies. / Under de föhållanden som reservoarens miljö erbjuder, definieras en petroleumvätska av dess termodynamiska och volymetriska egenskaper och av dess fysikalisk-kemiska egenskaper. För att korrekt simulera bearbetningen av dessa vätskor under produktion, deras beteende modelleras från experimentella data Med tillkomsten av nya regler och oflexibilitet som finns på tullbestämmelser vid gränserna idag, har forskningscenter stora svårigheter att få större mängder prover levererade. Av den anledningen, trots att det finns flera metoder för att karakterisera de olika komponenterna av råolja, tvingas laboratorier att vända sig mer och mer till alternativa analysmetoder som kräver mindre provvolymer: mikrodestillation, gaskromatografi, etc.   Mikrodestillation, som är en snabb och helt datoriserad teknik, visar sig kunna ersätta standarddestillation för analys av flytande petroleumprodukter. Fördelar med metoden jämfört med standarddestillering är minskad arbetstidsåtgång med minst en faktor 4. Därtill krävs endast en begränsad provvolym (några mikroliter) i jämförelse med standarddestillation.  [24]   Denna rapport syftar till att skapa en enkel modell som kan förutsäga avkastningskurvan av fysisk destillation, utan att använda mikrodestillationsteknik. De resultat som erhölls genom gaskromatografiska analyser möjliggjorde modelleringen av det vätskebeteendet hos det analyserade provet. Efter att ha identifierat och behandlat praktiskt taget alla viktiga aspekter av mikro destillation genom simuleringar med PRO/II, fann jag att, oberoende av inställningen och den termodynamiska metod som används,  det alltid finns stora skillnader mellan simulering och mikro destillation.   Resultatet visar att det fortfarande är svårt att skapa en modell som kan ersätta mikrodestillering och gaskromatografi på grund av differensen mellan simuleringsresultaten å ena sidan, och resultaten från mikrodestillering å andra sidan. Dessutom visade resultaten att mikrodestillation som analysmetod inte ger tillförlitliga resultat. Min förhoppning var att få ytterligare användbara resultat genom att studerar potentiella korrelationer emellan fler prover, men detta visade sig inte vara fallet. Jag anser att det skulle vara intressant att studera fler prover och använda en annan simulator för att bättre representera mikrodestillation. Detta skulle kunna vara ett intressant ämne för vidare studier.

La séparation dans le domaine pétrolier consiste a arranger ou déplacer des corps ou des classes d'espèces dans des régions différentes de façon a avoir plus de facilites a évaluer leurs propriétés ou bien a produire d'autres mélanges. Le travail, que nous présentons ici, est une contribution a la resolution numérique de certains problèmes rencontres dans l'étude de séparation du pétrole. Les problèmes étudiés, dans ce travail, concernent deux types de mélanges différents: mélanges complexes et mélanges simples. L'étude effectuée, sur différents problèmes de la gestion des mélanges, a conduit a mettre au point un logiciel interactif et visuel ainsi que plusieurs programmes d'expérimentation; ceci va permettre une exploitation numérique et graphique meilleure

In the eukaryotic nucleus, an immense length of DNA is compactly packaged to generate an ordered three-dimensional hierarchical structure called chromatin (van Holde, 1988; Wolffe, A.P, 1998). This organization forms a template for various DNA transaction processes like replication, transcription, recombination etc. The different stages of organization of the chromatin finally results in the 10,000-fold compaction observed in the metaphase chromosome. The problem of how the fibres of chromatin are folded has interested biologists and biochemists for decades. It has long been recognized that the Histones play a major part in this folding. However, the distinctly different roles of the Histones H2A, H2B, H3 and H4 on one hand and the lysine rich Histones such as Histone H1 and its cognates on the other, were not understood until after the discovery of the nucleosomes in the early 1970s. Some of the early insights into the structure of chromatin came through the digestion of nuclear chromatin with calcium-dependent endonucleases like micrococcal nuclease. A repeating kinetic intermediate of about 200 bp of DNA with Histones was obtained (Simpson, 1978). Based on repeating pattern of micrococcal nuclease digested chromatin and structural studies, Kornberg (1974) proposed that chromatin is composed of a flexible chain of repeating units of 100 A0 diameter. These units were termed as "nucleosomes" (Oudet et al, 1975). It then became clear that the Histones H2A, H2B, H3 and H4 were constituents of the nucleosome core particle whereas the lysine rich Histone H1 was somehow associated with the linker DNA between core particles. Hence, the formers are called core Histones and the latter as linker Histones. On further digestion of nucleosome, a nucleosome core was obtained in which wrapping of 146 bp of DNA about the Histone octamer to form the core particle provided the first level of folding. Electron microscopy and X-ray diffraction techniques suggested that this particle is a disk, 57 A0 thick and 110 A0 in diameter, and that the DNA is wound around the Histone core (Finch et al, 1977), But this cannot account for the many thousand-fold condensation of the DNA in the eukaryotic nucleus. The "string of beads" structure observed obviously could not satisfy the compaction requirement. It soon became evident that there exists some level of higher order folding of the chromatin fiber. In a classical paper, Finch and Klug (1976), showed that the extended nucleosomal filaments condense into irregular fibers of about 30 nm diameter in the presence of low concentrations of Mg 2+. Based on the data from earlier structural studies, these authors proposed a solenoid model in which nucleosomes were wrapped into a regular helix with a pitch of about 11nm. Later, it was observed that the formation of well defined fibers requires the presence of lysine rich Histones such as Histone H1.

Cette thèse avait pour objectif de développer de nouveaux systèmes d’extraction liquide-liquide compatibles avec le procédé Prayon pour la purification de l’acide phosphorique produit par voie humide. Une étude bibliographique complète des solvants d’extraction étudiés dans la littérature pour l’extraction liquide-liquide de l’acide phosphorique nous a permis d’identifier des candidats potentiellement intéressants. Une étude approfondie des propriétés d’extraction de ces systèmes et de leur sélectivité vis-à-vis des espèces métalliques nous a finalement permis de nous focaliser par la suite sur trois solvants d’extraction : le dibutyl éther (DBE), le diisobutyl carbinol (DiBC) dilué dans le diisopropyl éther (DiPE) et la Fentamine T0810 (ATS) dilué dans le DiPE. La formulation de ces mélanges a ensuite été optimisée en veillant à étudier le comportement de ces systèmes à chaque étape du procédé d’extraction liquide-liquide, c’est à dire l’extraction, la désextraction et le lavage. Cette étude a également permis de fixer les conditions opératoires optimales, notamment le rapport des volumes des phases. Au cours de cette étude, des phénomènes complexes de transitions de phases réversibles de la phase organique de monophasique vers biphasique (formation de troisième phase) et biphasique vers monophasique (retour à une phase organique unique) ont été mis en évidences expérimentalement. Pour finir, un modèle physicochimique d’extraction fondé sur des bilans de masse a été développé. Ce modèle s’avère très utile pour décrire l’extraction de l’acide phosphorique et de l’eau et la variation des volumes des phases au cours de l’extraction. / This PhD thesis was focused on the development of new extraction systems to purify phosphoric acid from wet phosphoric acid (WPA). The new system should be respectful of the current Prayon’s process flowsheet designed for the use of the mixture tri-n-butyl phosphate(TBP) and diisopropyl ether (DiPE) as extraction solvent. Firstly, extractants exhibiting different structures and functional groups were screened in order to assess their efficiency and selectivity towards phosphoric acid. Three new promising extraction systems were identified: diisobutyl ether (DBE), diisocarbinol (DiBC) in DiPE, and Fentamine T0810 (ATS) in DiPE. Secondly, our effort was directed to the comprehension of the physico-chemical phenomena involved in the extraction of phosphoric acid by the mixture TBP/DiPE at first, and enriched to describe the other systems studied later. Finally, a simulation model describing the solvent extraction of phosphoric acid by the solvent currently employed by Prayon is presented. This model accounts for the significant volume variation during the extraction of phosphoric acid and allows performing optimizations of extraction parameters even at very high phosphoric acid concentrations (6-14M).

Astrocyte Elevated Gene 1 (AEG1) is an oncogene for hepatocellular carcinoma (HCC). Its role in HCC pathogenesis has been well studied. A pan cancer analysis of gene expression in multiple databases identified TATA-box binding protein associated factor 2 (TAF2) as the gene that is most frequently co-expressed with AEG1. TAF2 is a protein that is involved in transcription of genes by RNA polymerase II. It is a factor that is dispensable for basal transcription but, required for activated transcription. It has also been shown to be involved in regulating cyclin levels and hence cell cycle progression. Bioinformatic analysis on data from different cancer databases confirmed the positive correlation of TAF2 expression with AEG1 expression, the over expression of TAF2 in HCC patients and poor survival of HCC patients with increasing TAF2. We confirmed the over expression of TAF2 in HCC cell lines using western blotting and HCC liver using immunohistochemistry. We established cell lines with stable knockdown of TAF2 expression. These clones showed significant decrease in their ability to invade and migrate but not their proliferation ability. This is in contrast to what has been observed in previous studies. We hypothesize that the knockdowns do not show any decrease in cellular proliferation since the remaining TAF2 in the cells is sufficient to produce cyclins and keep cell cycle undisturbed. The knockdown of TAF2 causes an increase in E-cadherin level and decrease in Snail protein expression which is a known negative regulator of E-cadherin. Knockdown of TAF2 causes cells to become more epithelial leading to a decrease in their ability to migrate and invade. This study shows that TAF2 is a potential oncogene that needs to be further studied.

Revisorn ska verka för allmänhetens bästa (Volcker, 2002) men verkligheten är långt mer komplicerad. Den allokerade tiden per uppdrag (tidsbudget) har minskat till följd av revisionsbranschens kommersialisering. Revisionsbyråerna behöver därför ta ställning till huruvida de kan tänkas genomföra ett revisionsuppdrag till ett lägre pris utan att kompromissa med kvalitén. Revisorer utsätts således för tidspress i form av time budget pressure då de tvingas genomföra revisionsuppdrag på kortare tid. Dysfunktionellt beteende är ofta följden av TBP (time budget pressure) som i sin tur sänker revisionskvalitén. Det saknas forskning som explicit undersöker hur TBP kan minskas. Uppsatsens syfte är att förklara huruvida ett belöningssystem kan användas för att lindra revisorns upplevda TBP. Ett välutvecklat belöningssystem kan möjligen vara lösningen då belöningar motiverar personalen. Empirin samlades in med hjälp av en webbaserad enkätundersökning. 350 e-mail innehållandes en länk till enkäten skickades ut till godkända samt auktoriserade revisorer på de fem största revisionsbyråerna i Sverige. E-mailet innehöll även en uppmaning att sprida enkäten vidare på kontoret i hopp om att nå revisorsassistenterna. 58 svar erhölls. Resultatet påvisar att revisorerna inte upplever TBP i någon stor utsträckning. Det är inte vanligt förekommande med yttre monetära belöningar bland revisorerna men inre icke-monetära belöningar förekommer i stor utsträckning. Belöningssystemen som implementeras motiverar revisorerna men belöningssystem, i sin helhet, kan inte användas för att lindra en revisors upplevda TBP. / Accountants are intended to further the public interest (Volcker, 2002) but the reality of the business is far more complicated. The allocated time per audit assignment (time budget) have been reduced as a consequence of the commercialization of the accountancy market. Accountancy firms are required to either accept a lower client fee or possibly lose the client. The cost-quality issue means that accountancy firms have to balance cost savings and quality of service and consequently the accountants are forced to finalize audit assignments in a shorter period of time. Thus time budget pressure (TBP) arises. Dysfunctional behaviour is a common outcome of TBP consequently affecting audit quality. There are however no research whose aim is to explain the factors possible of reducing TBP. The purpose of this thesis is to explain whether a reward system can be utilized to reduce TBP affecting accountants. A well-designed reward system is a plausible solution to the problem of TBP because of the fact that rewards motivates personnel. The empirical evidence was gathered using an online-questionnaire. 350 e-mails were sent to approved and authorized accountants currently working at one of the five largest accountancy firms in Sweden. The e-mail contained a link to the questionnaire as well as an appeal too forward the questionnaire internally with the intent of reaching the firms’ assistant accountants. 58 respondents participated. The results show that accountants does not experience a high degree of TBP. Extrinsic monetary rewards are perceived as frequently occurring and intrinsic non-monetary rewards are perceived as less-frequently occurring by the accountants. The reward system currently implemented are contributing to the accountants’ motivation but reward systems cannot be utilized to reduce TBP affecting accountants.

Neste trabalho são apresentados dois modelos para o ensaio de destilação ASTM D-86, desenvolvidos no simulador EMSO e validados por dados experimentais de frações de petróleo disponíveis na literatura. Estes modelos apresentam índice algébrico-diferencial igual a um, diferentemente do primeiro modelo proposto na literatura que apresentava índice algébrico-diferencial igual a 2, o qual não possibilitava ser resolvido pelos simuladores atuais. As predições obtidas com os modelos propostos geraram resultados com desvio médio em torno de 0,6 % em relação aos dados experimentais da literatura. Em seguida, foi estudado o método proposto para determinação de mistura substituta de componentes reais e foram propostas algumas alterações. Esta metodologia pode ser dividida em duas etapas consecutivas. A primeira etapa determina um conjunto de componentes reais e a segunda calcula a composição da mistura substituta de componentes reais de modo a caracterizar misturas complexas de composição desconhecida, como frações de petróleo, substituindo o conceito de pseudo-componentes. Para isso, o algoritmo se baseia em dados experimentais tais como a curva PEV, o °API, a massa molar média da mistura e outras propriedades globais disponíveis. Foram obtidos resultados que se mostraram satisfatórios. Para finalizar este trabalho, foi proposto um novo método para determinação da mistura substituta que utiliza a primeira etapa do algoritmo de determinação de mistura substituta e modificado por este trabalho. Em seguida, é realizada uma estimação dinâmica de parâmetros de condição inicial utilizando um dos modelos desenvolvidos neste trabalho para o ensaio de destilação ASTM D-86. A estimação é baseada principalmente na curva experimental da destilação ASTM D-86 e na densidade à 60°F (ou °API). Os resultados desta nova metodologia foram comparados com outros métodos de determinação de mistura substituta e constatou-se uma melhora na aproximação das suas propriedades quando comparadas com a mistura original de composição desconhecida. / This work presents two models for the assay of distillation ASTM D-86, developed in the EMSO Simulator and validated using experimental data of petroleum fractions available in the literature. These models showed differential-algebraic index equal to one, differently from the first model proposed in the literature that showed differential-algebraic index equal to two. Problems with an index higher than one are usually impossible to solve by modern simulators. The predictions obtained with the proposed models generated results with average deviation of about 0,6% in relation to those in the literature. After this, a method proposed in the literature to determinate the substitute mixture of real compounds for petroleum fractions was studied and slightly modified. This methodology can be divided in the two following steps. The first one determines a group of real components and the second one calculates the composition of the substitute mixture of the real components in order to characterize a complex mixture of unknown composition, as petroleum fractions. This methodology aims at replace the pseudo-components concept. To make this, the algorithm is based in experimental data as the TBP curve, the °API, the average molar mass of the mixture and others global properties available. The obtained results showed to be suitable. Finally, this work proposes a new method to determine the substitute mixture that uses the first step of the algorithm of determination of substitute mixture and modified in this work. Next, it was used a dynamic estimation of parameters in initial conditions using one of the models proposed in this work for the distillation assay ASTM D-86. The estimation is mainly based on distillation experimental curve ASTM D-86 and the density at 60°F (or °API). The results of this new methodology were com pared to other methods of determination of substitute mixture and it was found an evolution in the similarity of its properties when compared to the original mixture with unknown composition.

Neste trabalho são apresentados dois modelos para o ensaio de destilação ASTM D-86, desenvolvidos no simulador EMSO e validados por dados experimentais de frações de petróleo disponíveis na literatura. Estes modelos apresentam índice algébrico-diferencial igual a um, diferentemente do primeiro modelo proposto na literatura que apresentava índice algébrico-diferencial igual a 2, o qual não possibilitava ser resolvido pelos simuladores atuais. As predições obtidas com os modelos propostos geraram resultados com desvio médio em torno de 0,6 % em relação aos dados experimentais da literatura. Em seguida, foi estudado o método proposto para determinação de mistura substituta de componentes reais e foram propostas algumas alterações. Esta metodologia pode ser dividida em duas etapas consecutivas. A primeira etapa determina um conjunto de componentes reais e a segunda calcula a composição da mistura substituta de componentes reais de modo a caracterizar misturas complexas de composição desconhecida, como frações de petróleo, substituindo o conceito de pseudo-componentes. Para isso, o algoritmo se baseia em dados experimentais tais como a curva PEV, o °API, a massa molar média da mistura e outras propriedades globais disponíveis. Foram obtidos resultados que se mostraram satisfatórios. Para finalizar este trabalho, foi proposto um novo método para determinação da mistura substituta que utiliza a primeira etapa do algoritmo de determinação de mistura substituta e modificado por este trabalho. Em seguida, é realizada uma estimação dinâmica de parâmetros de condição inicial utilizando um dos modelos desenvolvidos neste trabalho para o ensaio de destilação ASTM D-86. A estimação é baseada principalmente na curva experimental da destilação ASTM D-86 e na densidade à 60°F (ou °API). Os resultados desta nova metodologia foram comparados com outros métodos de determinação de mistura substituta e constatou-se uma melhora na aproximação das suas propriedades quando comparadas com a mistura original de composição desconhecida. / This work presents two models for the assay of distillation ASTM D-86, developed in the EMSO Simulator and validated using experimental data of petroleum fractions available in the literature. These models showed differential-algebraic index equal to one, differently from the first model proposed in the literature that showed differential-algebraic index equal to two. Problems with an index higher than one are usually impossible to solve by modern simulators. The predictions obtained with the proposed models generated results with average deviation of about 0,6% in relation to those in the literature. After this, a method proposed in the literature to determinate the substitute mixture of real compounds for petroleum fractions was studied and slightly modified. This methodology can be divided in the two following steps. The first one determines a group of real components and the second one calculates the composition of the substitute mixture of the real components in order to characterize a complex mixture of unknown composition, as petroleum fractions. This methodology aims at replace the pseudo-components concept. To make this, the algorithm is based in experimental data as the TBP curve, the °API, the average molar mass of the mixture and others global properties available. The obtained results showed to be suitable. Finally, this work proposes a new method to determine the substitute mixture that uses the first step of the algorithm of determination of substitute mixture and modified in this work. Next, it was used a dynamic estimation of parameters in initial conditions using one of the models proposed in this work for the distillation assay ASTM D-86. The estimation is mainly based on distillation experimental curve ASTM D-86 and the density at 60°F (or °API). The results of this new methodology were com pared to other methods of determination of substitute mixture and it was found an evolution in the similarity of its properties when compared to the original mixture with unknown composition.

Neste trabalho são apresentados dois modelos para o ensaio de destilação ASTM D-86, desenvolvidos no simulador EMSO e validados por dados experimentais de frações de petróleo disponíveis na literatura. Estes modelos apresentam índice algébrico-diferencial igual a um, diferentemente do primeiro modelo proposto na literatura que apresentava índice algébrico-diferencial igual a 2, o qual não possibilitava ser resolvido pelos simuladores atuais. As predições obtidas com os modelos propostos geraram resultados com desvio médio em torno de 0,6 % em relação aos dados experimentais da literatura. Em seguida, foi estudado o método proposto para determinação de mistura substituta de componentes reais e foram propostas algumas alterações. Esta metodologia pode ser dividida em duas etapas consecutivas. A primeira etapa determina um conjunto de componentes reais e a segunda calcula a composição da mistura substituta de componentes reais de modo a caracterizar misturas complexas de composição desconhecida, como frações de petróleo, substituindo o conceito de pseudo-componentes. Para isso, o algoritmo se baseia em dados experimentais tais como a curva PEV, o °API, a massa molar média da mistura e outras propriedades globais disponíveis. Foram obtidos resultados que se mostraram satisfatórios. Para finalizar este trabalho, foi proposto um novo método para determinação da mistura substituta que utiliza a primeira etapa do algoritmo de determinação de mistura substituta e modificado por este trabalho. Em seguida, é realizada uma estimação dinâmica de parâmetros de condição inicial utilizando um dos modelos desenvolvidos neste trabalho para o ensaio de destilação ASTM D-86. A estimação é baseada principalmente na curva experimental da destilação ASTM D-86 e na densidade à 60°F (ou °API). Os resultados desta nova metodologia foram comparados com outros métodos de determinação de mistura substituta e constatou-se uma melhora na aproximação das suas propriedades quando comparadas com a mistura original de composição desconhecida. / This work presents two models for the assay of distillation ASTM D-86, developed in the EMSO Simulator and validated using experimental data of petroleum fractions available in the literature. These models showed differential-algebraic index equal to one, differently from the first model proposed in the literature that showed differential-algebraic index equal to two. Problems with an index higher than one are usually impossible to solve by modern simulators. The predictions obtained with the proposed models generated results with average deviation of about 0,6% in relation to those in the literature. After this, a method proposed in the literature to determinate the substitute mixture of real compounds for petroleum fractions was studied and slightly modified. This methodology can be divided in the two following steps. The first one determines a group of real components and the second one calculates the composition of the substitute mixture of the real components in order to characterize a complex mixture of unknown composition, as petroleum fractions. This methodology aims at replace the pseudo-components concept. To make this, the algorithm is based in experimental data as the TBP curve, the °API, the average molar mass of the mixture and others global properties available. The obtained results showed to be suitable. Finally, this work proposes a new method to determine the substitute mixture that uses the first step of the algorithm of determination of substitute mixture and modified in this work. Next, it was used a dynamic estimation of parameters in initial conditions using one of the models proposed in this work for the distillation assay ASTM D-86. The estimation is mainly based on distillation experimental curve ASTM D-86 and the density at 60°F (or °API). The results of this new methodology were com pared to other methods of determination of substitute mixture and it was found an evolution in the similarity of its properties when compared to the original mixture with unknown composition.

Global consumption of organophosphate esters (OPs), which are used as flame retardants and plasticizers, is rapidly increasing. Their use as additives in diverse applications poses a risk as they may be emitted from the products they are added to and be further transported in the environment. Therefore, the levels, distribution, and possible sources of 15 OPs, some of which are reported to be toxic, were investigated in indoor and outdoor environments. An exposure assessment was performed, and the exposure to OPs via inhalation was examined for five occupational groups. In addition, based on the findings of the studies, the total flow of OPs in Sweden was estimated. In indoor environments, the OPs detected in air and dust varied between the sites, but generally reflected the building materials, furniture etc. used in the premises. A majority of the analysed OPs were detected in all samples, and public buildings tended to have higher levels than domestic buildings. The chlorinated OPs dominated in indoor air and wipe samples from vehicles. They were also abundant in the dust samples. Some occupational groups were significantly more exposed to OPs than others. Aircraft technicians, for example, were exposed to about 500 times more tributyl phosphate than day care centre personnel. Upon domestic and industrial cleaning, OPs are discharged with the wastewater via the sewage system to sewage treatment plants (STPs). Irrespective of the size of the STPs investigated, they had similar levels of OPs in their influents, indicating that products containing OPs are widely used by the communities they serve. In some cases, it was possible to trace elevated levels of individual OPs to specific sources. The OPs were poorly removed from the wastewater, and the chlorinated OPs especially tended to pass through the STPs without being removed or degraded. Thus, levels of OPs in their effluents were also similar, as were the levels in their sludge. Of the total amounts of OPs entering the STPs, 50% was emitted to the recipients via the effluent. Hence, there is room for significant improvement in the treatment processes. Carps living in a pond, receiving STP effluent were found to contain relatively high levels of OPs compared to perch collected in lakes from background locations. Air and road traffic were also identified as sources of OPs: the concentration of total OPs in snow samples decreased with increasing distance from a major road intersection, and OPs were detected in aircraft lubricants and hydraulic fluids and in waste oil from cars and lorries. OPs are emitted from both diffuse and direct sources to the environment and may then be spread by long-range air transport, rivers and streams. This probably explains why OPs were also detected in air and fish from background locations. Finally, OPs are ubiquitous substances in both indoor and outdoor environments. The possibility that prolonged exposure to OPs at the levels found may cause adverse effects, for instance in aqueous organisms, cannot be excluded. For example, the OP levels in snow were of the same magnitude as reported effect concentrations. Similarly, in some premises, indoor exposure to OPs was close to the suggested guideline value. However, since these studies include only a limited number of samples, and data regarding the health and environmental effects of OPs are sparse, no definitive conclusions regarding their possible environmental effects can be drawn. / Den globala konsumtionen av organiska fosfatestrar (OP) för användning som flamskyddsmedel och mjukgörare har ökat kraftigt på senare tid. Det breda användningsområdet för dessa additiv medför en risk att de kan avges från de produkter de är satta till och transporteras vidare ut i miljön. Följaktligen undersöktes källor till, halter av, och fördelning i inom- och utomhusmiljöer av 15 OP, varav en del har toxiska effekter. Vidare har exponering för OP i bl.a bostäder och offentliga byggnader beräknats. Utöver detta undersöktes exponeringen för OP via inandning hos 5 yrkesgrupper. Slutligen användes resultaten för att uppskatta det totala flödet av OP i Sverige. I de olika inomhusmiljöerna uppmättes ett flertal OP i varierande halter i damm och luft, men generellt speglade halterna byggnadsmaterial, möbler etc. som fanns i lokalerna. De offentliga lokalerna tenderade att uppvisa högre halter än privata hus, förmodligen beroende på högre brandskyddskrav. Klorerade OP dominerade i inomhusluft samt i avstrykningsprov från fordon och förekom även i höga halter i damm. Vissa yrkesgrupper var exponerade för betydligt högre halter OP än andra, t.ex. exponerades flygtekniker för upp till 500 ggr högre lufthalter av tributylfosfat jämfört med förskollärare. I samband med våtskurning i inomhusmiljöer (hushåll, industrilokaler, osv.) släpps avsevärda mängder OP ut i avloppet och når till sist reningsverk. Oberoende av storlek på reningsverken var halterna av OP relativt lika, i vardera ingående vatten och slam, vilket indikerar en bred användning av OP i samhället. I vissa fall kunde specifika källor till OP i avloppsvattnet spåras. Exempelvis hade två av reningsverken högre halter av en klorerad OP jämfört med övriga reningsverk. Dessa behandlade vatten från en skumplastfabrik, respektive en fabrik som tillverkar flamskyddad färg. Avskiljningsgraden av OP från avloppsvatten visade sig generellt vara dålig, i synnerhet klorerade OP tenderade att passera genom reningsverken utan att degraderas eller avskiljas från vattnet. Av den mängd OP som nådde reningsverken släpptes 50 % ut till miljön via utflödet. Som ett resultat av detta uppvisade karpar från en damm påverkad av utflödet från ett reningsverk höga halter OP jämfört med abborrar från referenssjöar. Det finns därför anledning att förbättra tekniken på reningsverken. Flyg- och vägtrafik kunde också identifieras som källor till OP i miljön. OP uppmättes i hydrauloljor och smörjmedel för flygplan samt i spillolja från bilar och lastbilar. Vidare minskade totalhalten OP i snöprov med ökat avstånd från en större vägkorsning. OP släpps således ut från både diffusa och direkta källor och kan sedan spridas vidare via luft och vattendrag. Därmed var det inte förvånande att OP även påträffades i luft och fisk från bakgrundslokaler. Avslutningsvis förekommer OP i varierande halter i såväl inom- som utomhusmiljöer. Det kan inte uteslutas att långvarig exponering för de halter av OP som uppmätts skulle kunna orsaka negativa effekter hos t.ex vatten- eller jordlevande organismer. I smälta snöprov från en flygplats uppmättes exempelvis halter av OP i samma storleksordning som rapporterade effektkoncentrationer. Dessutom visade sig den beräknade exponeringen av OP, i några av de provtagna inomhuslokalerna, uppgå till halter nära det föreslagna riktvärdet för OP i Tyskland. Dessa studier inkluderar dock ett begränsat antal prov och provtyper och kunskapen om dessa föreningars miljö- och hälsoeffekter är bristfällig. Därför bedöms underlaget som för litet för att några definitiva slutsatser ska kunna dras angående OPs eventuella effekter på miljön.