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In this thesis, I report the gas phase infrared spectra of some polycyclic aromatic hydrocarbons (PAHs) namely 1, 5-, 1, 6-, and 2, 6-dimethyl naphthalenes (DMNs); 2, 4-, 2, 6-, 2, 7-, and 2,8-dimethyl quinolines (DMQs); and 1, 9-, 2, 4-, and 3, 9-dimethyl phenanthrenes (DMPs) and diols such as 1, 2-ethylene glycol (1,2-EG) and 1, 4-butanediol (1,4-BD). Assignment of the IR spectra has been done with the help of DFT calculations followed by scaled quantum mechanical force field calculations. Chapter 1 gives a brief introduction to PAHs and diols. A brief survey of literature pertinent to their sources, their importance, experimental techniques for identification of PAHs and different conformers of diols and intramolecular interactions between the two hydroxyl groups in the diols are presented. The scope and motivation of the present investigation have been described at the end of the chapter. In Chapter 2, I have discussed all the methods used in carrying out this work. The details of the experimental FT IR set-up and quantum-chemical calculations employed in this work have been elaborated in this chapter. The subsequent chapters 3 - 5 deal with the experimental and theoretical results obtained for DMNs, DMQs, and DMPs. In chapter 3, infrared spectra of 1,5-, 1,6-, and 2,6-DMN have been described. The spectra have been recorded using a multi-pass gas cell coupled with Nexus-870 spectrometer (Thermonicolet, US). Qualitatively, spectral assignments have been made with the help of calculated doubly scaled (one scaling factor for the C-H stretching and another factor for the non C-H stretching frequencies) harmonic frequencies at the B3LYP/6-31G* level of theory. The spectral features to distinguish three different isomers of DMN have been identified. In chapter 4, IR spectra of 2,4-, 2,6-, 2,7-, and 2,8-DMQ in the gas phase have been recorded using a high resolution Vertex-70 (Bruker Optics, Germany) FT-IR spectrometer. DFT calculations have been carried out in order to get harmonic and anharmonic frequencies and their intensities at the B3LYP/6-31G* level of theory. Unambiguous assignments of IR bands could not be made with the help of anharmonic or selectively scaled harmonic frequencies. Therefore, scaled quantum mechanical (SQM) force field calculations were performed where force fields in local coordinates were scaled for getting frequencies in close agreement with experiment. Potential energy distributions (PEDs) of the normal modes in terms of the local coordinates of the molecule using a modified UMAT program in the QCPE package were also obtained in order to identify the nature of the fundamental vibration modes. In chapter 5, I have presented the gas phase IR spectra of 1,9-, 2,4-, and 3,9-DMP. The harmonic and anharmonic frequencies and their intensities were obtained at the B3LYP/6-31G* and B3LYP/6-311G** levels of theory. I have carried out SQM calculations for the assignment of the experimental frequencies in a similar fashion as was done for the DMQs. In chapter 6, IR spectra of two diols namely 1,2-ethylene glycol and 1,4-butane diol are reported and discussed. DFT calculations have been carried out for the harmonic fundamental frequencies and intensities at the experimental temperatures with 10 unique chosen conformers of the diols at the B3LYP/6-311++G** level of theory. Gas phase equilibrium population analysis has been done in order to generate the theoretical spectrum with the weighted average contributions from the 10 conformers to match the experimental spectrum. The hydrogen bond enthalpy, strength and nature have been investigated in details. From this experimental and theoretical studies, it has been concluded that the intramolecular hydrogen bond is absent in 1,2-EG at ordinary temperatures whereas it is present in 1,4-BD. vi Chapter 7 is the concluding chapter where the main work done in this thesis is summarized and future direction is presented.

With the rising demand for fossil fuels, Northern Canada has seen an unprecedented increase in petrochemical development. These developments are often associated with emissions of PAHs, a group of hydrophobic organic contaminants that are known to be carcinogenic and otherwise harmful to humans. Due to their hydrophobic nature, PAHs tend to bind to organic matter and can be produced through both anthropogenic and natural processes, making them ubiquitous in the environment. Therefore, in addition to impacts from petrochemical developments, changes to climatic conditions, such as increased forest fire disturbance and primary production also have the potential to alter delivery of organic carbon (OC) and PAHs to ecosystems. However, very little is known as to how the combined stressors of climate change and petrochemical development may affect environmental deposition of these contaminants. The concentrations and composition of parent and alkyl PAHs were analysed in radiometrically-dated sediment cores from lakes with one of four different types of petrochemical development in their catchments: (1) in-situ oil sands extraction (Cold Lake, AB); (2) open-pit oil sands extraction (Fort McMurray, AB); (3) abandoned conventional natural gas exploration (Mackenzie Delta Uplands, NWT); and (4) conventional gas and oil extraction (Cameron Hills, NWT). PAH deposition to lake sediments was also compared to climate reconstructions using climate proxies (diatom assemblages, inferred chlorophyll a and its diagenetic products, and Rock Eval carbon fractions as well as %OC). PAH sources were differentiated between potential pyrogenic and petrogenic origin over a period that extends to pre-industrial times using ratios of specific PAHs that can be traced to their potential source. Sediment cores from Cold Lake, AB showed concentrations of the sum of alkyl PAHs greater than those of parent PAHs, while all other cores show the reverse trend. A comparison of the % change of PAH concentrations from pre-development to post-development sediments between the four regions, showed that the greatest increase in concentrations of PAHs occurred in the Athabasca oil sands region. PAH profiles in the conventional regions have been historically dominated by mixed sources (pyrogenic PAHs from general background atmospheric inputs and petrogenic PAHs from the surrounding hydrocarbon-rich soils). While cores from the Fort McMurray area show a clear shift from pyrogenic sources (primarily wood and coal burning) in earlier sediments to petrogenic sources in more modern sediments, and the Cold Lake cores show some shifting sources to those dominated by pyrogenic sources in modern sediments. Organic carbon was significantly correlated with the sum of parent PAHs in 2 out of the 6 NWT cores that were examined for climate change impacts, while all other PAH parameters (concentration and composition) do not correlate significantly with any of the climate proxies. Establishing background concentrations and sources of PAHs in aquatic ecosystems is essential for understanding the natural environmental variations in these contaminants. Moreover, as both petrochemical activity and impacts from climate change are predicted to intensify in the future, studies such as this one allow us to build a solid understanding of how PAH deposition to northern lakes has responded to the warming climate and whether PAHs have been altered as a result of petrochemical activity.

Beaucoup de micropolluants organiques sont présents dans les boues. Leur possible impact sur l'environnement contribue à accroître leur intérêt scientifique et social. La digestion anaérobie présente un potentiel certain pour dégrader ces composés. Dans ce travail, il a été développé un modèle dynamique pour décrire le devenir de micropolluants hydrophobes au cours de la digestion anaérobie de boues contaminées. Le modèle est basé sur une distribution des composés dans quatre-compartiments et il a démontré que la transformation des micropolluants est bien simulée si l'on considère une cinétique de co-métabolisme pour la dégradation et si la phase aqueuse constitue le compartiment biodisponible. Dans ce modèle, la sorption des micropolluants hydrophobes est envisagée sur deux phases différentes: la matière particulaire et la matière dissoute/colloïdale (DCM), car la sorption sur le compartiment DCM peut influencer la disponibilité des composés et donc leur biodégradation. Il a été conclu que le transfert de micropolluants hydrophobe ne limite pas leur biodégradation, et que leur devenir est régi par l'état d'équilibre de sorption-désorption. Afin d'identifier quelle(s) étape(s) de la digestion permet le co-métabolisme, de nouvelles expérimentations ont été menées en utilisant des inhibiteurs des Méthanogènes. Elles suggèrent que la dégradation anaérobie des micropolluants implique principalement des microorganismes non-méthanogènes. En effet, la transformation co-métabolique des micropolluants serait principalement liée à la population acidogènes, comme le montre le modèle avancé proposé. Le modèle proposé est potentiellement utile pour mieux comprendre la distribution des micropolluants, prédire leur devenir dans des conditions anaérobies et aider à optimiser le processus de fonctionnement pour leur épuisement. / Many organic micropollutants are present in sludge. Their possible impact on the environment contributes to their increasing scientific and social interest. Anaerobic digestion has been shown as a potential biological process for removing these compounds. In this work, a dynamical fate model is developed for hydrophobic micropollutant under anaerobic digestion of contaminated sludge. The model is based on a four-compartment distribution and demonstrated that the micropollutant transformation is well simulated if considering a co-metabolic kinetic and the aqueous phase as the bioavailable compartment. In this model, the sorption of hydrophobic micropollutants is considered on two different phases: particulate matter and dissolved/colloidal matter (DCM). Indeed, the sorption onto DCM can influence the availability of compounds for biodegradation. It was concluded that hydrophobic micropollutant transfer does not limit their biodegradation, and that their fate is governed by sorption-desorption equilibrium state. In order to evaluate which step of the anaerobic pathway is implied in the co-metabolism of micropollutants, experimental set-ups were designed using different way to inhibit the Methanogens. The experimental inhibition of methanogenic activity suggests that the anaerobic degradation of micropollutants mainly involves non-methanogenic microorganisms. Indeed, the co-metabolic transformation of micropollutants would be mainly linked to acidogens population as it was shown through the proposed advanced model. This latter is potentially useful to better understand the micropollutant distribution, predict their fate under anaerobic condition and help to optimize the operation process for their depletion.

Oil spills, especially in water have happened throughout the years. The consequences from this kind of incident have always been a threat to marine life and take a lot of money and time to clean up. The forensic investigations of oil usually focus on oil spill in water, however, this kind of investigation can be applied on more areas, such as in sexual offense cases and arson. The oil from the crime scene and the oil from the suspected source are analyzed and compared to each other to see if the compositions match. The aim of this thesis was to optimize the clean-up process of heavy fuel oil (HFO) using solid-phase extraction (SPE) according to the European Committee for standardization (CEN) 15522-2 method. HFOs are black oils, containing particles and soot which will decrease injector performance. Thus, a cleanup procedure is attractive when analyzing such samples. The three factors of optimization in this study were elution volumes, solvents, and SPE sorbents.The SPE method used in this study was to use the cartridges as a filter; therefore, the samples were both loaded and eluted with an organic solvent, in this case dichloromethane (DCM) or dichloromethane/heptane (DCM/Hp). The gas chromatography mass spectrometry (GC-MS) analysis method used is described in Annex B in the CEN 15522-2 method.Concluding, increasing the eluent volume did not indicate improvement on the extraction method. In terms of the solvents, both dichloromethane and dichloromethane/heptane showed similar results. The percentage weathering plots (PW-plots) showed that the SPE sorbents (dual layer florisil/Na2SO4, florisil and silica gel sorbents) worked similar. The overall conclusion from this thesis work was that further optimization must be made before implementing the method.

Biochar is created during the pyrolysis of organic biomass. Once added into the soil, it can improve its features. Biochars made from sewage sludge have various compositions. It is because of the vast difference between entrance materials. Organic pollutants can be absorbed into its surface during the cooling proces sof pyrolysis. If released into the enviroment, these compounds can cause inhibition of plant growth, get into food chains and adversely affect living organisms. Organic pollutans are determined most often by GC/MS after organic solvent extraction.

This thesis deals with a contaminated area in the municipality of Östersund where a gas plant has previously been operating from 1914 to 1951. Operations at the property where the gas plant has been located currently consist of a workshop and commercial premises with associated car parking. In order to be able to build on the gas plant area, the municipality intends to implement post-treatment measures in the area. The substances found in the contaminated area (hotspot area E) are polycyclic aromatic hydrocarbons (PAH), aromatics, arsenic, nickel, lead and benzene. Measurement data indicate that these substances have been found at high levels, above the Swedish Environmental Protection Agency's guideline values for contaminated soil. Many areas today are polluted to the level that they pose great risks to the environment and people, and this thought requires the treatment of contaminated soil. A risk assessment for hotspot area E determined that PAH, aromatics, arsenic, nickel, lead and benzene pose an unacceptable risk, and the area is therefore deemed to need remediation. Based on nearby buildings, in-situ soil remediation is a suitable approach that fits. This study summarizes the progress made in remediation research and shows that soil remediation methods have different advantages and disadvantages, and different strains on human health and the environment. Based on this study, it may be more appropriate to wait for more efficient or cheaper remediation techniques to be developed, but with the idea that these substances are volatile, toxic, and dangerous to us humans and the environment. This means that they pose a potential risk to society and a tendency to spread easily. Conclusions that can be drawn are that all in-situ methods included in this work can be applied in Sweden based on the geological conditions. In order to achieve optimum in-situ soil remediation, site-specific conditions, such as large groundwater flow or heterogeneous soil, control the choice of remediation method.

Thesis are aimed to the optimization and validation of the QuEChERS method for determination of polycyclic aromatic hydrocarbons in solid matrices of hydrosphere. The QuEChERS method was also used for determination of polycyclic aromatic hydrocarbons in real samples and for comparison of measured results, time and material costs of the method with currently employed methods: (1) accelerated solvent extraction connected with gel permeation chromatography (ASE/GPC), and (2) ultrasonic extraction connected with solid phase extraction (UZ/SPE). According to the validation criteria, the QuEChERS method is suitable for the determination of polycyclic aromatic hydrocarbons in solid matrices of hydrosphere. The QuEChERS technique provides comparable results to ASE/GPC and UZ/SPE. In terms of price and time for sample preparation, the QuEChERS method allows (unlike the methods ASE/GPC and UZ/SPE) fast and inexpensive determination of polycyclic aromatic hydrocarbons in solid samples of hydrosphere.

In der vorliegenden Arbeit wurde die elektronische Struktur verschiedener undotierter und mit Alkalimetallen beziehungsweise 2,3,5,6-Tetrafluoro-7,7,8,8-tetracyanoquinodimethan (F 4 TCNQ) dotierter, polyzyklischer aromatischer Kohlenwasserstoffe (PAK) untersucht. Diese Untersuchungen waren motiviert durch verschiedene Veröffentlichungen in denen supraleitendes Verhalten an unterschiedlichen alkalimetalldotierten PAK beschrieben wurde. Erste Studien erfolgten an undotiertem 1,2:8,9-Dibenzopentacen (DBP) und Pentacen unter Nutzung von Photoelektronenspektroskopie (PES), Elektronenenergieverlustspektroskopie (EELS) und Dichtefunktionaltheorie (DFT). Die spektroskopischen Methoden zeigten für beide Materialien eine große Ähnlichkeit der elektronischen Zustände, vor allem im niederenergetischen Bereich, welche durch die theoretischen Ergebnisse bestätigt wurde. Die elektronische Ähnlichkeit beider Materialien ist im starken Gegensatz zu dem in der Literatur bei Dotierung beobachteten Verhalten, bei dem Pentacen zum Mott-Isolator wird, während DBP Supraleitung zeigt. Weitere Untersuchungen erfolgten an Picen und Coronen. Bandstrukturrechnungen zeigten, dass Picen vermutlich ein stark korreliertes Elektronensystem besitzt. Neben dem mit PES ermittelten Ionisationspotential und der Austrittsarbeit waren auch die mit EELS gemessenen optischen Bandlücken der beiden Materialien sehr ähnlich. Unterschiede zeigten sich hingegen vor allem in der Dichte der gemessenen Zustände von Picen und Coronen am Ferminiveau. Bei der Untersuchung der elektronischen Eigenschaften von mit Kalium-dotierten Picen und Coronen wurde trotz der erfolgreichen Dotierung in keinem der untersuchten Filme eine Zustandsdichte am Ferminiveau beobachtet somit wurde auch keiner der untersuchten Filme metallisch. Dasselbe Verhalten konnte auch für Natrium-dotierte Filme beobachtet werden. Eine Diskussion dieses Ergebnisses, welches im Gegensatz zu der von anderen Gruppen in dotierten Molekülen beobachteten Supraleitung steht, erfolgte im Hinblick auf die Bildung unterschiedlich dotierter Phasen, Elektron-Phonon-Kopplung, der Formierung von Bi-Polaronen und Korrelationseffekten. Für ein weitergehendes Verständnis der dotierungsinduzierten elektronischen Eigenschaften in den untersuchten Molekülen wurden diese nicht nur mit Alkalimetallen, sondern teilweise auch mit elektronenziehenden Molekülen wie F 4 TCNQ interkaliert. Dabei entstanden Kristalle verschiedener Ladungstransfersalze. Eine ausführliche Charakterisierung erfolgte für Picen/F 4 TCNQ-Kristalle, welche im Rahmen dieser Arbeit zum ersten Mal hergestellt und untersucht wurden. Dabei wurde zunächst deren Kristallstruktur mit Röntgendiffraktometrie (XRD) bestimmt. Eine Abschätzung der Größe des Ladungstransfers innerhalb der Molekülpaare aus Picen/ F 4 TCNQ erfolgte über Infrarot- und Bindungslängendaten, die auf diese Weise gefunden Werte wurden zusätzlich durch DFT-Rechnungen untermauert. Transportmessungen zeigten außerdem, dass die hergestellten Kristalle entlang ihrer Hauptwachstumsrichtung Isolatoren sind. Die Untersuchung der elektronischen Eigenschaften wurde mit EELS und PES an Picen/ F 4 TCNQ -Dünnfilmen durchgeführt, welche durch die Verdampfung der Einkristalle hergestellt wurden. Die Molekülpaare zeigen einen Ladungstransfer, der neue elektronische Anregungen im Niederenergiebereich der mit EELS gemessenen Verlustfunktion hervorruft. Im weiteren Verlauf der Arbeit erfolgte eine Diskussion bezüglich des Charakters und der Lokalisierung dieser neuen Anregungen. Bei den PES-Messungen zeigte sich der Ladungstransfer durch energetische Verschiebungen in den gemessen Rumpfniveauspektren sowie durch im Vergleich zu den reinen Materialien deutlich veränderte Ionisationspotentiale. Trotz des erfolgreichen Ladungstransfers und der damit verbundenen Füllung von unbesetzten Zuständen mit Elektronen in F 4 TCNQ wurde jedoch in den Valenzbandspektren keine Emission am Ferminiveau beobachtet. DFT-Rechnungen ermöglichten schließlich Aussagen über den Charakter des Ladunstransfers und die daraus resultierende, fehlende Zustandsdichte am Ferminiveau.

Canadian bitumen is mainly transported in a diluted form via pipeline and train, all posing a risk as they can lead to the release of diluted bitumen (dilbit) in the environment. In the summer of 2018, a collaborative large-scale field experiment was conducted at the International Institute for Sustainable Development - Experimental Lakes Area (IISD-ELA), a world-renowned aquatic research facility. The research objectives of the Boreal lake Oil Release Experiment by Additions to Limnocorrals (BOREAL) project were to understand the fate, behaviour, and potential toxic effects of dilbit in a freshwater Boreal lake to inform evidence-based management strategies for the transport of dilbit. A range of controlled dilbit spills was performed in seven 10 m diameter limnocorrals (~100,000 L of water) resulting in environmentally realistic dilbit:water dilutions ranging from 1:69,200 to 1:504, representing the upper half of the distribution of oil spill sizes in North America in the last decade. Additionally, two limnocorrals not treated with dilbit were studied as controls. This thesis identifies the bioaccumulating compounds derived from naturally weathered dilbit in adult giant floater mussels (Pyganodon grandis), to determine the rates at which they were accumulated and excreted. More specifically, the bioaccumulation potential and toxicokinetic parameters of polycyclic aromatic compounds (PACs) and various metals were assessed in mussels exposed ex situ for 41 days (25 days of exposure and 16 days of depuration) to water from the limnocorrals. These compounds have shown to be toxic, carcinogenic, and mutagenic to aquatic organisms. Mussels exposed to dilbit-contaminated water experienced significantly greater TPACs concentrations (0.40 – 0.90 µg L-1, n=12) compared to mussels from the Control (0.017 µg L-1, n=4). Furthermore, dilbit-contaminated water had a higher proportion of alkylated PACs compared to their parent counterpart, demonstrating petrogenic PAC profiles. We detected significantly greater TPACs concentrations in mussels exposed to dilbit-contaminated water (25.92 – 27.79 µg g-1, ww Lipid, n=9, at day 25 of the uptake phase) compared to mussels from the Control (average of 2.62 ± 1.95 µg g-1, ww Lipid; ±SD, n=17). Alkylated PACs represented 96.4 ± 1.8%, ±SD, n=12 of TPACs in mussels from dilbit-contaminated treatments at day 25 of the uptake phase, indicating the importance of conducting a more inclusive assessment of petrochemical mixtures as most studies only focus on parent PACs. From first-order one-compartment models derived from nonlinear curve fitting of the accumulation phase or sequential modelling method, uptake (0.66 – 24.65 L g-1 day-1, n=87) and depuration (0.012 – 0.37 day-1, n=87) kinetic rate constants, as well as bioconcentration factors (log values from 3.85 – 6.12 L kg-1, n=87) for the 29 PACs that bioaccumulated in mussels suggested that alkylated PACs have greater bioaccumulation potential compared to their parent PAC counterpart. Results from this study also demonstrated that giant floater mussels could be used to biomonitor PAC contamination following oil spills as PACs accumulated in mussel tissue and were still present following the 16 day depuration phase. The results of this study are the largest, most comprehensive set of toxicokinetic and bioaccumulation information of PACs (44 analytes) in freshwater mussels obtained to date. Metal contamination following the controlled dilbit spill was minimal, but mussels exposed to water contaminated with naturally weathered dilbit experienced elevated concentrations of dissolved zinc (30.26 – 38.26 µg L-1, n=12) compared to the mussels in the uncontaminated water (6.75 ± 3.31 µg L-1, n=4), surpassing the Canadian water quality guidelines for the protection of aquatic life. However, it is not clear if dilbit contamination caused elevated zinc concentrations in the water as other factors, such as limnocorral building materials and/or galvanized minnow traps used in the limnocorrals, could have contributed to zinc contamination. Nonetheless, giant floater mussels did not accumulate zinc in their tissues.