Synthetic musk compounds are artificial organic substances commonly used as fragrant constituents of personal care products as parfums, cosmetics, detergents, in-house cleaning and washing agents. Given their large area of applications and their ability to be persistent, they leaked into all parts of ecosystem, especially aquatic one. There have been a big focus on studiyng these compounds, their properties and fate in the different parts of ecosystems in the last years. The aim of master's thesis was carry out the determination of five representatives (habanolide, exaltolide, ambrettolide, musk MC4 and ethylene brassylate) of macrocyclic musk compounds in waste water samples from influent and effluent of three water treatment plants (WWTP Brno-Modřice, WWTP Lednice and WWTP Mikulov). One of the main tasks was to perform a method optimisation for the determination of selected musk compounds in waste water and evaluation and interpretation of the results. Solid phase microextraction (SPME) technique was used for the extraction of analytes, consequently gas chromatography-mass spectrometry was used for analysis of selected analytes. Following evaluation the removal efficiency of musk compounds in the waste water treatment plant was assessed.

This work was focused on the determination of musk compounds in various components of the environment. Synthetic musk compounds are organic substances commonly used as fragrant constituents of detergents, perfumes, cosmetics and other personal care products (PCPs). These compounds contaminate the aquatic environment through municipal wastewater from sewage treatment plants. The result is accumulation of these analytes in the environment and their occurrence in food chain. Synthetic fragrances are commonly detected also in human body; these substances generally belong among relatively new persistent organic pollutants (POPs) because of their persistence, bioaccumulation, and potential toxicity. The aim of this work was to optimize the methods for the determination of selected synthetic fragrances in wastewater (municipal, industrial) and in fish muscle. These analytes were determined in wastewater [the wastewater treatment plant (WWTP) Brno – Modřice, cosmetic manufacturing plant] and in fish Squalius cephalus that had been caught in the river Svratka. The selected analytes (14 substances) originate from the group of nitromusk, polycyclic musk and linear musk compounds. Solid phase microextraction (SPME) [for wastewater samples] and pressurized solvent extraction (PSE) [for fish samples] were used for isolation of analytes from real samples. The identification and quantification of analytes were carried out by high resolution gas chromatography coupled with mass spectrometry detection (GC-MS). The results show that galaxolide (g.L-1) and tonalide (tenths of g.L-1) were polycyclic musk compounds which were found at the highest concentration level in influent and also in effluent samples from the WWTP Brno – Modřice. The most extended nitromusk compound was musk ketone (hundredths of g.L-1). Linear musk compounds were detected in all influent samples (g.L-1). The overall removal efficiency of synthetic musk compounds from wastewater in the WWTP varies within the following ranges: nitromusk compounds 34.4 % – 85.4 %, polycyclic musk compounds 36.7 % – 53.3 % and linear musk compounds 90.5 % – 99.9 %. On the basis of the results it can be stated that wastewater (effluent from the WWTP) is the primary source of musk compounds, especially of the polycyclic ones in the environment. It has been also shown that ultrafiltration used in a cosmetic plant is a highly efficient technology for removing nitromusk and polycyclic musk compounds from industry wastewater. The results from evaluation of the fish contamination by musk compounds show that galaxolide was the substance which reached the highest concentration levels (tens of g.kg-1 l.w.). The results corroborate ubiquitous occurrence of musk compounds in the environment and reduction of using of nitromusk compounds due to their potential toxic properties. It has been shown that the insufficiency of the purifying procedures used in the WWTP Brno – Modřice has a significant influence on the concentration level of polycyclic musk compounds (tonalide, galaxolide) in fish caught from the river Svratka.

Indiana University-Purdue University Indianapolis (IUPUI) / Analyses of tobacco products and their usage are well-researched and have implications in analytical chemistry, forensic science, toxicology, and medicine. As such, analytical methods must be developed to extract compounds of interest from tobacco products and biological specimens in order to determine tobacco exposure. In 2009, R.J. Reynolds Tobacco Co. released a line of dissolvable tobacco products that are marketed as a smoking alternative. The dissolvables were extracted and prepared by ultrasonic extractions, derivatization, and headspace solid phase microextraction (SPME) with analysis by gas chromatography-mass spectrometry (GC-MS). The results show that the compounds present are nicotine, flavoring compounds, humectants and binders. Humectant concentrations vary among different tobacco types depending on the intended use. Humectants were quantified in various tobacco types by GC and “splitting” the column flow between a flame ionization detector (FID) and an MS using a microfluidic splitter in order to gain advantage from the MS’s selectivity. The results demonstrated excellent correlation between FID and MS and show that MS provides a higher level of selectivity and ensures peak purity. Chemometrics was also used to distinguish products by tobacco type. Hair is a common type of evidence in forensic investigations, and it is often subjected to mitochondrial DNA (mtDNA) analysis. Preliminary data was gathered on potential “lifestyle” markers for smoking status as well as any indications of subject age, gender, or race by investigating the organic “waste” produced during a mtDNA extraction procedure. The normally discarded organic fractions were analyzed by GC-MS and various lipids and fatty acids were detected. At this point, a total vaporization-SPME (TV-SPME) method was theorized, developed, and optimized for the specific determination of nicotine and its metabolite, cotinine. The theory of TV-SPME is to completely vaporize an organic extract which will eliminate the partitioning between the sample and the headspace, thereby simplifying the thermodynamic equilibrium. Parameters such as sample volume, incubation temperature, and extraction time were optimized to achieve the maximum analyte signal. Response surface methodology (RSM) is a statistical model that is very useful in predicting and determining optimum values for variables to ensure the ideal response. RSM was used to optimize the technique of TV-SPME for the analysis of nicotine and cotinine. Lastly, quantitation of nicotine and cotinine in human hair typically requires large sample sizes and extensive extraction procedures. Hence, a method using small sample sizes and a simple alkaline digestion followed by TV-SPME-GC-MS has been developed. Hair samples were collected from anonymous volunteers and nicotine and cotinine were identified and quantitated in the hair of tobacco users.

No description available.

L’industrie des produits de l’érable est particulièrement importante en Amérique du Nord. Elle est touchée par un phénomène naturel qui se produit en fin de saison de récolte. Il s’agit de l’altération du goût du sirop ; un goût fort désagréable se développe et se nomme goût de bourgeon vu qu’il coïncide au bourgeonnement des feuilles d’érable. Des coûts et du temps sont impliqués à sa récolte et sa production. Cependant, un sirop d’érable avec un goût de bourgeon est vendu à moindre prix. Il constitue donc une perte potentielle d'argent pour les producteurs. Au fil du temps, ils ont appris à se fier à des signes distincts de la nature pour déterminer le début du bourgeonnement. Néanmoins, il est important de le détecter hâtivement pour les producteurs et de mieux comprendre les changements moléculaires associés au défaut de saveur de type bourgeon. Plusieurs travaux sur les produits de l’érable ont été effectués durant le dernier siècle, mais ce n’est que récemment que des projets de recherche sont centrés sur le goût de bourgeon. La détection de celui-ci est certes importante, mais il y est aussi question de mieux connaître la variation de la composition du sirop ou de la sève d’érable, afin de mieux comprendre le phénomène. Tel que décrit dans l’introduction de ce mémoire, on connaît maintenant mieux la composition du sirop d’érable, même que quelques solutions ont été proposées à notre problème, mais beaucoup de questions restent sans réponse que ce mémoire tentera de résoudre. C'est dans ce contexte que cette étude se pose. En visant à identifier les molécules responsables du défaut de goût de type bourgeon que l’on peut retrouver dans le sirop d’érable, nous espérons aider à mieux cibler le problème et à mieux comprendre le métabolisme et, éventuellement, comprendre comment ce goût se développe. Dans un second temps, la découverte de molécules pas encore rapportées, au meilleur de notre connaissance, comme étant présentes dans le sirop d’érable est aussi visée, sans égard à la classification du sirop. Les travaux de ce mémoire contribueront, ultimement, à trouver une façon d’empêcher la formation de ce goût et surtout un moyen de l’éliminer. Pour ce, une première partie correspondant à l’analyse des composés volatils a été effectuée par SPME et GC-MS sur 78 échantillons de sirop d’érable. L’analyse statistique des résultats par PCA cible 42 composés et associe chacun d’entre eux au sirop d’érable avec le défaut de saveur ou alors au sirop sans défaut de saveur. Parmi elles, seules 36 ont pu être identifiées par leurs spectres de masse. La seconde partie correspond à l’analyse des composés non volatils par UPLC-QTOF et UPLCMS/MS. La méthode a été optimisée pour cibler les molécules relativement apolaires par rapport aux sucres et aux acides aminés présents dans le sirop d’érable. Au total, 20 échantillons de sirop ont été analysés, dont 10 à défaut de saveurs de type bourgeon et 10 sans défaut. Pour cette partie, l’analyse de composantes principales a encore une fois été utilisée pour classer les types de sirop à l’étude selon les composés détectés. Ainsi, le mémoire avance les connaissances moléculaires liées à l’émergence du défaut de bourgeon dans le sirop d’érable. / The maple products industry is particularly important in North America. It is affected by a natural phenomenon that occurs at the end of the harvest season. It’s the alteration of the taste of the syrup; a very unpleasant taste develops and is called buddy flavour since it coincides with the budding of maple leaves. Costs and time are involved in its harvest and production. When maple syrup is associated with the buddy taste, its commercial value is lower. Therefore, it contributes to a loss of money for producers. Over time, they have learned to rely on distinct signs from nature to determine the onset of budding. However, methods are needed to detect it and research is needed to better understand the molecular changes in maple syrups. Several research projects on maple products have been carried out during the last century, but it is only recently that research projects have focused on the buddy flavour. They focus on determining the variation in the composition of maple syrup or sap, but also on better understanding of the phenomenon. We now know more than ever about the composition of maple syrup, on top of that some solutions have been proposed to our problem, but many questions remain unanswered and it is obvious that there is still so much to discover. It is in this context that this study arises. By aiming to identify the molecules responsible for the buddy flavour defects that can be found in maple syrup, we hope to help on targeting the problem and better understanding the metabolism of maple trees and, eventually, how the buddy taste develops. Secondly, it is aimed at discovering molecules not yet reported, to the best of our knowledge, as being present in maple syrup regardless of the classification of the syrup. This will contribute, ultimately, in finding a way to prevent the formation of this taste and a way to eliminate it. Thus, the first part of this master’s thesis corresponds to the analysis of volatile compounds by SPME and GC-MS on 78 maple syrup samples. Statistical analysis of the results targets 42 compounds and associates them with either maple syrup with flavour defects or with maple syrup with regular flavour maple syrup. Among these, 36 molecules could be identified by mass spectrometry. To extract correlations from our data, the principal component analysis (PCA) ensued. The second part corresponds to the analysis of non-volatile compounds by UPLC QTOF and UPLC-MS/MS. The method has been optimized to target molecules that are relatively apolar compared to sugars and most of the amino acids present in maple syrup. A total of 20 syrup samples were analyzed, including 10 with bud-like flavour defects and 10 with no defects. For both parts, PCA was once again used to determine which types of syrup under study are the compounds associated with. Taken together, the results presented in this master’s thesis advances knowledge on the molecular origins of the buddy flavour defect in maple syrups.

Environmental and health aspects of road materials have been discussed for a long time, mostly regarding bitumen and bitumen fumes. However, just a few studies on other types of road materials have been reported. In this doctoral study, two types of materials, asphalt release agents and bituminous sealants, were investigated with regard to chemical characterization and emission profiles. Besides conventional test methods, solid-phase microextraction (SPME) technique was applied for emissions profiles screening and quantitative analysis. General description of main characteristics of asphalt release agents and bituminous sealants is given, and a comprehensive state-of-the-art on SPME technique is presented, especially on methodologies for analyzing mono- and polycyclic aromatic hydrocarbons (MAHs and PAHs) in different sample matrices. In the experimental study, chemical characterization of the two material types was performed using conventional methods, including fourier transform infrared spectroscopy - attenuated total reflectance (FTIR-ATR), gel permeation chromatography (GPC), mass spectrometry (MS) and gas chromatography – mass spectrometry (GC-MS). General patterns regarding functional groups and molecular weight distribution were studied. In the case of asphalt release agents, more detailed information on chemical compositions, especially the contents of MAHs and PAHs, was obtained. General information on emission proneness of asphalt release agents was obtained using thermogravimetric analysis (TGA) and MS. Using headspace(HS)-SPME and GC-MS, emission profiles of asphalt release agents were characterized at different temperatures, whereas the profiles of bituminous sealants were obtained solely at room temperature. The results presented were used for ranking the materials with regard to degree of total emission as well as emission of hazardous substances. The applicability of HS-SPME for quantitative analysis of MAHs in asphalt release agents and emulsion-based bituminous sealants was investigated. The use of a surrogate sample matrix was concerned, and experimental parameters influencing the HS-SPME procedure, such as equilibration and extraction time, as well as effects of sample amount and matrices, were studied. The methods were evaluated with regard to detection limit, accuracy as well as precision. Different calibration approaches including external calibration, internal calibration and standard addition were investigated. The determination of MAHs in asphalt release agents and emulsion-based bituminous sealants using HS-SPME-GC-MS was conducted. / QC 20100913

Chromatography and extraction techniques, and also chemiluminescence have been utilized to develop new rapid and informative tools in the evaluation of long-term properties and environmental effects of polymeric materials. Methods were developed for classification of materials and for early and rapid degradation detection. Degradable polyethylene films were classified on the basis of their incorporated prooxidant systems using chromatographic fingerprinting of carboxylic acids, the dominating type of degradation product. The fingerprints were also shown to be useful for prediction of the degradation states and evaluation of the degradation mechanisms. Classification and prediction models were obtained by Multivariate Data Analysis, where the diacids were grouped according to both their type of prooxidant system and their state of degradation. The use of total luminescence intensity (TLI) measurements was also investigated as a means of classifying films and for the early detection of degradation. Comparisons were carried out with common techniques, e.g. FTIR and DSC, after both thermal and UV oxidation. TLI gave an earlier detection of degradation and was more sensitive than carbonyl index and crystallinity measurements to relative differences in degradation between the materials. It furthermore offered complementary information regarding changes in activation energies during the course of the degradation. The results were compared with the chromatographic fingerprints. A new way to evaluate the low temperature long-term stabilisation efficiency of antioxidants was investigated. A prooxidant was used to obtain catalytic oxidation, instead of using thermal acceleration, to evaluate the stabilisation efficiency of antioxidants at low temperatures but still during reasonably short aging times. Comparisons were made between polypropylene films stabilised with primary antioxidants (Irganox 1076, Irganox 1010 and α-tocopherol) with and without the prooxidant manganese stearate at different temperatures. The relative efficiencies of the antioxidants obtained under prooxidant acceleration test correlated better than thermal acceleration test with the results of a long-term low temperature test. Additives in plastic packaging materials may affect the environment after migration from the packaging to e.g. their contents, especially if they consist of organic aqueous solutions or oils. The use of Solid-Phase Microextraction (SPME) for the specific task of extraction from an organic aqueous solution such as a simulated food or pharmaceutical solution consisting of 10 vol-% ethanol in water was investigated. Methods were developed and evaluated for extraction both with direct sampling and with headspace sampling. If the extraction method and temperature were selected to suit the concentration levels of the analytes, it was possible to quantify several degradation products simultaneously. Comparisons made with Solid Phase Extraction showed the advantage of SPME for this purpose. / QC 20100929

Hippocrates predicted many years ago that breath could tell something related with our health. On his treaties, he indicated that when the body starts moving after sleeping, and breathe with more frequency, something hot and acid is expelled with air. It is possible to predict a disease from breath, but it has not been until recent years that last developments in breath analysis has allowed to detect compounds precisely and to associate the presence of these compounds to certain diseases. The use of breath analysis in clinical diagnosis and exposure to contaminants presents great advantages as this is a non-invasive technique, compared with other techniques such as blood or urine analyses. Two new instrumental methodologies have been developed in the present thesis, which are based on adsorbent micro-traps, specifically designed for the analysis of volatile compounds in breath and environmental samples. These equipments are versatile and low cost, compared to other commercially available instrumentations. One of the methodologies developed has been designed for the analysis volatile compounds in breath samples, showing efficiency and resolutions unknown up to know. It has allowed detecting exposure to volatile contaminants in a range of concentrations that the current techniques cannot achieve. The second equipment has been developed for the analysis of the same contaminants in other biological matrixes, in this case blood. It has been used to assess the mechanism followed by the inhaled compounds when entering the human body. These new methodologies were evaluated in different exposure studies. 2,5-dimethylfurean was detected with a high sensitivity and allowed to determine the smoking habits of a wide group of individuals, also 48 hours after smoking. The levels of contamination due environmental tobacco smoke were also evaluated in different environments. The high sensitivity of the developed techniques allowed us to demonstrate the contamination of passive smokers by environmental tobacco smoke (ETS) after few hours of being in contact with. Breath levels of the smoking biomarker after few hours in contact with ETS where at the same level that those found in smokers who smoke few cigarettes per day / Que l’alè ens deia alguna cosa de la nostra salut ja ho va intuir Hipòcrates. Al Tractat Mèdic hi va escriure: “Així, doncs, quan el cos es posa en moviment després de dormir i respira amb més freqüència, quelcom calent i àcid és expulsat amb l’aire. D’això en venen malalties si hom no pren precaucions.” Sí, de l’olor de l’alè s’intuïen malalties però no ha estat fins als darrers anys, que els nous avanços en les tècniques d’anàlisi no han proporcionat els mecanismes adients per detectar els compostos de forma inequívoca i poder associar la seva presència a l’alè a determinades malalties. Tant des d’un punt de vista mèdic com d’exposició a contaminants, el principal avantatge de poder disposar d’una anàlisi d’alè consisteix en la metodologia diagnòstica, que no és invasiva i, per tant, no presenta els inconvenients associats a altres tècniques convencionals, com son l’anàlisi de sang i d’orina. En aquesta tesi s’han desenvolupat dos noves metodologies instrumentals, basades en micro-trampes d’adsorció, especialment dissenyades per a l’anàlisi de compostos volàtils en mostres gasoses, principalment mostres ambientals i mostres d’alè humà. Aquests nous equipaments es caracteritzen per la seva versatilitat i molt baix cost, si es comparen amb els equips comercials actuals. Un dels prototips s’ha dissenyat per a l’anàlisi de mostres d’alè, mostrant una eficàcia i resolució desconeguda fins ara, el que ha permès detectar l’exposició a contaminants volàtils a uns nivells que les tecnologies actuals no permeten assolir. El segon equipament ha estat desenvolupat per permetre analitzar els mateixos contaminants en matrius biològiques, en aquest cas sang, i poder determinar de quina manera i en quin percentatge els compostos que inhalem per exposició arriben a entrar en el cos humà. Aquestes noves metodologies s’han avaluat en diferents estudis d’exposició. S’ha pogut detectar un compost, el 2,5-dimetilfuran, amb una elevada sensibilitat per a la detecció de l’hàbit fumador de les persones, inclús després de més de 48 h d’haver fumat una cigarreta. També s’han estudiat els nivells de contaminació pel fum ambiental del tabac que tenen lloc en diferents ambients (locals de fumadors i no-fumadors). L’elevada sensibilitat de les tècniques desenvolupades ha permès demostrar “in-situ” per primera vegada que els fumadors passius només requereixen unes poques hores de contacte en un ambient contaminat pel fum del tabac per presentar nivells de contaminació a l’alè similars als dels fumadors de poques cigarretes al dia

<p>Technology has become increasingly more prevalent in all aspects of society since the age of the computer. The United States Military has successfully integrated the powerful processing capabilities of computers to increase the proficiency and lethality of its Soldiers, Sailors, Marines, and Airmen. However, this increased lethality comes at risk due to the inherent vulnerabilities of computer systems to spyware, malware, and counterfeit components. Inspired by the ability of canines to seek out and find electronic devices, this research sought methods to characterize components by their “scent” using precise analytical tools. Using these tools, this thesis sought to develop and utilize non-invasive methods to show proof-of-concept for electronic device classification by volatile compounds unique to different types of components. The findings of this research proved that electronic components that vary by age, origin, type, or manufacturer emit different volatile compounds available for detection using modern two-dimensional gas chromatography and solid-phase microextraction technologies. If developed further, the methods used in this research have the potential for application in the United States Department of Defense to ensure that all electronic components installed in their systems are authentic, come from a trusted source, and can be relied upon in even the most stressful operating conditions.</p>

Indiana University-Purdue University Indianapolis (IUPUI) / Pipe bombs are a common form of improvised explosive device, due in part to their ease of construction. Despite their simplistic nature, the lethality of pipe bombs should not be dismissed. Due to the risk of harm and their commonality, research into the pipe bomb deflagration process and subsequent chemical analysis is necessary. The laboratory examination of pipe bomb fragments begins with a visual examination. While this is presumptive in nature, hypotheses formed here can lead to subsequent confirmatory exams. The purpose of this study was to measure the mass and velocity of pipe bomb fragments using high speed video. These values were used to discern any trends in container type (PVC or black/galvanized steel), energetic filler (Pyrodex or double base smokeless powder), and ambient temperature (13°C and -8°C). The results show patterns based on container type, energetic filler, and temperature. The second stage of a laboratory exam is chemical analysis to identify any explosive that may be present. Legality calls for identification only, not quantitation. The purpose of this study is to quantitate the amount of explosive residue on post-blast pipe bomb fragments. By doing so, the instrumental sensitivities required for this type of analysis will be known. Additionally, a distribution of the residue will be mapped to provide insight into the deflagration process of a device. This project used a novel sampling technique called total vaporization solid phase microextraction. The method was optimized for nitroglycerin, the main energetic in double base smokeless powder. Detection limits are in the part per billion range. Results show that the concentration of residue is not uniform, and the highest concentration is located on the endcaps regardless of container type. Total vaporization solid phase microextraction was also applied to automotive racing samples of interest to the National Hot Rod Association. The purpose of this project is two-fold; safety of the race teams in the form of dragstrip adhesive consistency and monitoring in the form of fuel testing for illegal adulteration. A suite of analyses, including gas chromatography mass spectrometry, infrared spectroscopy, and evaporation rate, were developed for the testing of dragstrip adhesives. Gas chromatography mass spectrometry methods were developed for both nitromethane based fuel as well as racing gasolines. Analyses of fuel from post-race cars were able to detect evidence of adulteration. Not only was a novel technique developed and optimized, but it was successfully implemented in the analysis of two different analytes, explosive residue and racing gasoline. TV-SPME shows tremendous promise for the future in its ability to analyze a broad spectrum of analytes.