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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
201

[en] OPTIMIZATION OF QUECHERS METHOD IN MUSSEL FOR THE DETERMINATION OF POLYCYCLIC AROMATIC HYDROCARBONS (PAHS) / [pt] OTIMIZAÇÃO DO MÉTODO QUECHERS EM MEXILHÃO PARA DETERMINAÇÃO DE HIDROCARBONETOS POLICÍCLICOS AROMÁTICOS (HPAS)

05 October 2021 (has links)
[pt] Os hidrocarbonetos policíclicos aromáticos (HPAs) de origem antrópica representam uma classe de contaminantes de relevância ambiental por serem derivados de múltiplas fontes petrogénicas e/ou pirolíticas e por apresentarem efeitos tóxicos e carcinogênicos. Quando encontrados em pescados de consumo comercial, podem apresentar um risco adicional para a saúde humana. A análise de HPAs em biota é um desafio analítico, devido à complexidade da matriz e aos níveis baixos de concentração que representam risco para o consumo de pescados. Esse trabalho tem como objetivo otimizar e validar o método QuEChERS para análise de HPAs em tecidos biológicos como uma alternativa aos métodos convencionais. O método QuEChERS apresenta características importantes para a Química Verde, ou seja, reduz o consumo excessivo de solventes, reagentes, quantidade de amostra, tempo, entre outros fatores que diminuem o impacto ambiental. Os parâmetros que afetam a eficiência do método foram estudados e concluiu-se que a etapa de purificação constituída por Z-sep+ com uma coluna fina de sílica e alumina apresentou melhores condições de purificação do extrato. A determinação dos compostos por cromatografia a gás acoplada à espectrometria de massas (GC-MS) nos forneceu resultados com alta resolução, seletividade e detectibilidade. A linearidade e sensibilidade do método apresentou valores maiores que 0,990 para todos os HPAs, numa faixa de concentração de 1 ng mL-1 a 50 ng mL-1 no extrato final; limites de detecção e quantificação nos intervalos de 0,377 a 7,45 ng g-1 e 1,13 a 22,36 ng g-1. Os percentuais de recuperação do método ficaram na faixa de 70 a 130 porcento. O procedimento validado permite quantificar HPAs em biota marinha de forma rápida, a baixo custo, livre de interferentes na análise instrumental por GC-MS e em níveis de quantificação que permitem avaliar a qualidade de pescados para consumo humano segundo padrões internacionais. / [en] Polycyclic aromatic hydrocarbons (PAHs) of anthropogenic origin represent a class of contaminants of environmental relevance because they are derived from multiple petrogenic and/or pyrolytic sources and because they have toxic and carcinogenic effects. When found in commercially relevant fish, they can pose an additional risk to human health. The analysis of HPAs in biota is an analytical challenge, due to the complexity of the matrix and the low levels of concentration that pose a risk to fish consumption. This work aims to optimize and validate the QuEChERS method for analysis of PAHs in biological tissues as an alternative to conventional. The QuEChERS method presenting important characteristics for Green Chemistry, that is, reducing the excessive consumption of solvents, reagents, sample quantity, time, among other factors that reduce the environmental impact. The parameters that affect the efficiency of the method were studied and it was concluded that the purification step consisting of Z-sep+ with a thin column of silica and alumina presented better conditions for extract purification. The determination of compounds by gas chromatography coupled with mass spectrometry (GC-MS) provided us with results with high resolution, selectivity and detectability. The linearity and sensitivity of the method presented values greater than 0.990 for all PAHs, in a concentration range from 1 ng mL-1 to 50 ng mL-1 in the final extract; limits of detection and quantification in the ranges of 0.377 to 7.45 ng g -1 and 1.13 to 22.36 ng g -1. The method s recovery percentages ranged from 70 to 130 percent. The validated procedure allows quantifying PAHs in marine biota quickly, at low cost, free from interferences in the instrumental analysis by GC-MS and at quantification levels that allow the quality of fish for human consumption to be assessed according to international standards.
202

[pt] DESENVOLVIMENTO DE MÉTODO MULTIRESÍDUO EM GC-MS/MS E LÓGICA FUZZY NO ESTUDO DE PAHS, PCBS, PBDES E PESTICIDAS ORGANOCLORADOS E SUA APLICAÇÃO EM SISTEMAS COSTEIROS DO BRASIL / [en] MULTIRESIDUE METHOD DEVELOPMENT IN GC-MS/MS AND FUZZY LOGIC IN THE STUDY OF PAHS, PCBS, PBDES AND ORGANOCHLORINE PESTICIDES AND THEIR APPLICATION IN COASTAL SYSTEMS IN BRAZIL

LEONARDO GRIPP BOM AMORIM 31 August 2023 (has links)
[pt] O atual trabalho teve como objetivo o desenvolvimento de um método multiresíduo e aplicação em testemunhos sedimentares para uma análise geocronológica da contaminação da Baía de Sepetiba por quatro classes de contaminantes orgânicos: (i) hidrocarbonetos policíclicos aromáticos (HPAs), (ii) bifenilos policlorados (PCBs); (iii) éteres difenílicos polibromados (PBDEs) e (iv) pesticidas organoclorados (OCPs). Além dos analitos contemplados no método desenvolvido, foram analisados outros parâmetros (HPAs alquilados, Biomarcadores de petróleo, Hidrocarbonetos Alifáticos, Carbono Orgânico Total e Nitrogênio Total) para que fosse possível uma análise mais aprofundada das fontes e da origem da MO e de compostos associados ao petróleo. Os testemunhos sedimentares foram coletados entre julho e outubro de 2016 e foram datados pela análise da atividade do decaimento de 210Pb e validado usando perfis de Zn e Cd. O método desenvolvido é baseado na extração ultrassônica com uma mistura de diclorometano:metanol (9:1 v/v) e cromatografia gasosa acoplada com análise de espectrometria de massa em tandem (GC-MS/MS) no modo de monitoramento de reações múltiplas (MRM). Um total de 89 compostos, dentre HPAs, PCBs, OCPs e PBDEs, foram identificados usando dois padrões de íon produto/precursor para cada analito. O limite de detecção do método (MDL; 0,001 – 0,055 ng g-1) e limite de quantificação do método (MQL; 0,002 – 0,184 ng g-1) estão abaixo dos níveis de poluição aceitáveis adotados pelas diretrizes internacionais de qualidade de sedimentos. O método, que foi publicado na revista Analytical and Bioanalytical Chemstry em maio de 2022, mostrou-se seletivo, sensível, preciso e linear, com a vantagem de reduzir o tempo de manuseio da amostra e a quantidade utilizada de materiais como solvente e adsorventes. A fim de analisar de forma mais aprofundada as fontes e origens dos HPAs nos testemunhos analisados, foi aplicado uma análise de dados baseada na Lógica Fuzzy, mais especificamente pelo algoritmo Fuzzy C-Means (FCM). Para que tivéssemos um melhor embasamento teórico da aplicação dessa ferramenta, um artigo foi publicado na revista Ocean and Coastal Research em fevereiro de 2022, com base na reavaliação estatística dos dados de dois trabalhos sobre contaminação do sedimento de baías costeiras por HPAs. Resultados obtido por meio de ferramentas de avaliação tradicionais foram comparadas com aqueles obtidos por FCM, que apresentaram maior detalhamento qualitativo. Embora a Lógica Fuzzy não produza interpretações quantitativas, sua aplicação gera dados adequados para que se evite uma inferência enviesada de fontes de contaminação de HPAs. A aplicação do método na análise dos testemunhos sedimentares foi bem-sucedida e a maioria das camadas apresentou valores de OCPs e PBDEs abaixo do MQL. Os valores de PCBs variaram de <MQL a 1,47 ng g-1 (média de 0,24 ± 0,38 ng g-1) em T18 e de 0,35 a 6,24 ng g-1 (média de 1,82 ± 1,37 ng g-1) em T26. Os HPAs variaram de 67,97 a 404,61 ng g-1 (média de 192,38 ± 98,48 ng g-1) em T18 e de 154,59 a 685,47 ng g-1 (média de 382,55 ± 168,45 ng g-1) em T26. / [en] The present work aimed at developing a multiresidue method and application in sedimentary testimonies for a geochronological analysis of the contamination of Sepetiba Bay by four classes of organic contaminants: (i) polycyclic aromatic hydrocarbons (PAHs), (ii) polychlorinated biphenyls (PCBs); (iii) polybrominated diphenyl ethers (PBDEs) and (iv) organochlorinated pesticides (OCPs). In addition to the analytes contemplated in the method developed, other parameters were analyzed (alkylated PAHs, petroleum biomarkers, aliphatic hydrocarbons, total organic carbon and total nitrogen) to allow a more in-depth analysis of the sources and origin of organic matter and compounds associated with petroleum. Sediment cores were collected between July and October 2016 by Gonçalvez et al. (2020) and were dated by analysis of 210Pb decay activity and validated using Zn and Cd profiles. The developed method is based on ultrasonic extraction with a mixture of dichloromethane:methanol (9:1 v/v) and gas chromatography coupled with tandem mass spectrometry analysis (GC-MS/MS) in multiple reaction monitoring (MRM) mode. A total of 89 compounds, among PAHs, PCBs, OCPs, and PBDEs, were identified using two product/precursor ion standards for each analyte. The method detection limit (MDL; 0.001 - 0.055 ng g-1) and method quantification limit (MQL; 0.002 - 0.184 ng g-1) are below acceptable pollution levels adopted by international sediment quality guidelines. The method, which was published in the journal Analytical and Bioanalytical Chemstry in May 2022, was shown to be selective, sensitive, accurate, and linear, with the advantage of reducing sample handling time and the amount used of materials such as solvent and adsorbents.In order to further analyze the sources and origins of PAHs in the analyzed core samples, we applied a data analysis based on Fuzzy Logic, more specifically the Fuzzy C-Means (FCM) algorithm. In order to have a better theoretical basis for the application of this tool, an article was published in the journal Ocean and Coastal Research in February 2022, based on the statistical re-evaluation of data from two studies on sediment contamination of coastal bays by PAHs. Results obtained through traditional assessment tools were compared with those obtained by FCM, which showed greater qualitative detail. Although Fuzzy Logic does not produce quantitative interpretations, its application generates adequate data to avoid biased inference of PAH contamination sources. The application of the method in the analysis of the sediment cores was successful and most layers showed OCPs and PBDEs values below the MQL. PCBs values ranged from <MQL to 1.47 ng g-1 (mean 0.24 ± 0.38 ng g-1) in T18 and from 0.35 to 6.24 ng g-1 (mean 1.82 ± 1.37 ng g-1) in T26. PAHs ranged from 67.97 to 404.61 ng g-1 (mean 192.38 ± 98.48 ng g-1) at T18 and from 154.59 to 685.47 ng g-1 (mean 382.55 ± 168.45 ng g-1) at T26.
203

EVALUATING THE EFFECTIVENESS OF A HAND-WASHING INTERVENTION ON DERMAL ABSORPTION OF POLYCYCLIC AROMATIC HYDROCARBONS, DNA ADDUCTS, AND 1-HYDROXYPYRENE LEVELS IN AUTOMOTIVE MECHANIC TRAINEES

BOOTH-JONES, ANGELA DAMITA 22 May 2002 (has links)
No description available.
204

THE IMPACT OF CADMIUM ON A MULTI-SPECIES BIOFILM DEGRADING NAPHTHALENE AND THE ROLE OF HYDROGEN PEROXIDE IN CADMIUM-BIOFILM INTERACTION

JIN, PENG 02 July 2007 (has links)
No description available.
205

Semipermeable membrane devices as integrative tools for monitoring nonpolar aromatic compounds in air

Söderström, Hanna January 2004 (has links)
<p>Air pollutants pose a high risk for humans, and the environment, and this pollution is one of the major environmental problems facing modern society. Active air sampling is the technique that has been traditionally used to monitor nonpolar aromatic air pollutants. However, active high volume samplers (HiVols) require a power supply, maintenance and specialist operators, and the equipment is often expensive. Thus, there is a need to develop new, less complicated sampling techniques that can increase the monitoring frequency, the geographical distribution of the measurements, and the number of sites used in air monitoring programs. In the work underlying this thesis, the use of semipermeable membrane devices (SPMDs) as tools for monitoring gas phase concentrations of nonpolar aromatic compound was evaluated using the compound classes polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), alkylated PAHs (alkyl-PAHs) and nitrated PAHs (nitro-PAHs) as test compounds. </p><p>High wind-speeds increased the uptake and release in SPMDs of PAHs and PCBs with log K<sub>OA</sub> values > 7.9, demonstrating that the uptake of most nonpolar aromatic compounds is controlled by the boundary layer at the membrane-air interface. The use of a metal umbrella to shelter the SPMDs decreased the uptake of PAHs and PCBs by 38 and 55 percent, respectively, at high wind/turbulence, and thus reduced the wind effect. Further, the use of performance reference compounds (PRCs) to assess the site effect of wind on the uptake in SPMDs reduced the between-site differences to less than 50 percent from as much as three times differences in uptake of PCBs and PAHs. However, analytical interferences reduced the precision of some PRCs, showing the importance of using robust analytical quality control.</p><p>SPMDs were shown to be efficient samplers of gas phase nonpolar aromatic compounds, and were able to determine local, continental and indoor spatial distributions of PAHs, alkyl- PAHs and nitro-PAHs. In addition, the use of the SPMDs, which do not require electricity, made sampling possible at remote/rural areas where the infrastructure was limited. SPMDs were also used to determine the source of PAH pollution, and different approaches were discussed. Finally, SPMDs were used to estimate the importance of the gas phase exposure route to the uptake of PAHs in plants. The results demonstrate that SPMDs have several advantages compared with HiVols, including integrative capacity over long times, reduced costs, and no need of special operators, maintenance or power supply for sampling. However, calibration data of SPMDs in air are limited, and spatial differences are often only semi-quantitatively determined by comparing amounts and profiles in the SPMDs, which have limited their use in air monitoring programs. In future work, it is therefore important that SPMDs are properly sheltered, PRCs are used in the sampling protocols, and that calibrated sampling rate data, or the SPMD-air partition data, of specific compounds are further developed to make determination of time weighted average (TWA) concentrations possible.</p>
206

Semipermeable membrane devices as integrative tools for monitoring nonpolar aromatic compounds in air

Söderström, Hanna January 2004 (has links)
Air pollutants pose a high risk for humans, and the environment, and this pollution is one of the major environmental problems facing modern society. Active air sampling is the technique that has been traditionally used to monitor nonpolar aromatic air pollutants. However, active high volume samplers (HiVols) require a power supply, maintenance and specialist operators, and the equipment is often expensive. Thus, there is a need to develop new, less complicated sampling techniques that can increase the monitoring frequency, the geographical distribution of the measurements, and the number of sites used in air monitoring programs. In the work underlying this thesis, the use of semipermeable membrane devices (SPMDs) as tools for monitoring gas phase concentrations of nonpolar aromatic compound was evaluated using the compound classes polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), alkylated PAHs (alkyl-PAHs) and nitrated PAHs (nitro-PAHs) as test compounds. High wind-speeds increased the uptake and release in SPMDs of PAHs and PCBs with log KOA values &gt; 7.9, demonstrating that the uptake of most nonpolar aromatic compounds is controlled by the boundary layer at the membrane-air interface. The use of a metal umbrella to shelter the SPMDs decreased the uptake of PAHs and PCBs by 38 and 55 percent, respectively, at high wind/turbulence, and thus reduced the wind effect. Further, the use of performance reference compounds (PRCs) to assess the site effect of wind on the uptake in SPMDs reduced the between-site differences to less than 50 percent from as much as three times differences in uptake of PCBs and PAHs. However, analytical interferences reduced the precision of some PRCs, showing the importance of using robust analytical quality control. SPMDs were shown to be efficient samplers of gas phase nonpolar aromatic compounds, and were able to determine local, continental and indoor spatial distributions of PAHs, alkyl- PAHs and nitro-PAHs. In addition, the use of the SPMDs, which do not require electricity, made sampling possible at remote/rural areas where the infrastructure was limited. SPMDs were also used to determine the source of PAH pollution, and different approaches were discussed. Finally, SPMDs were used to estimate the importance of the gas phase exposure route to the uptake of PAHs in plants. The results demonstrate that SPMDs have several advantages compared with HiVols, including integrative capacity over long times, reduced costs, and no need of special operators, maintenance or power supply for sampling. However, calibration data of SPMDs in air are limited, and spatial differences are often only semi-quantitatively determined by comparing amounts and profiles in the SPMDs, which have limited their use in air monitoring programs. In future work, it is therefore important that SPMDs are properly sheltered, PRCs are used in the sampling protocols, and that calibrated sampling rate data, or the SPMD-air partition data, of specific compounds are further developed to make determination of time weighted average (TWA) concentrations possible.
207

Compost bioremediation of oil sludge by using different manures under laboratory conditions

Ubani, Onyedikachi 06 1900 (has links)
This study was conducted to measure the reduction in polycyclic aromatic hydrocarbons (PAHs) content in oil sludge by co-composting the sludge with pig, cow, horse and poultry manures under laboratory conditions. Four kilograms of soil spiked with 800g of oil sludge was co-composted differently with each manure in a ratio of 2:1 (w/w) spiked soil: manure and wood-chips in a ratio of 2:1 (w/v) spiked soil: wood-chips. Control was set up similar as the one above but without manure. Mixtures were incubated for 10 months at room temperature. Compost piles were turned weekly and moisture level was maintained at between 50% and 70%. Moisture level, pH, temperature, CO2 evolution and oxygen consumption were measured monthly and the ash content at the end of experimentation. Bacteria capable of utilizing PAHs were isolated, purified and characterized by molecular techniques using polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE), amplification of the 16S rDNA gene using the specific primers (16S-P1 PCR and 16S-P2 PCR) and the amplicons were sequenced. Extent of reduction of PAHs was measured using automated soxhlet extractor with Dichloromethane as the extraction solvent coupled with gas chromatography/mass spectrometry (GC/MS). Temperature did not exceed 27.5OC in all compost heaps, pH ranged from 5.5 to 7.8 and CO2 evolution was highest in poultry manure at 18.78μg/dwt/day. Microbial growth and activities were enhanced. Bacteria identified were Bacillus, Arthrobacter and Staphylococcus species. Results from PAH measurements showed reduction between 77 and 99%. The results from the control experiments may be because it was invaded by fungi. Co-composting of spiked soils with animal manures enhanced the reduction in PAHs. Interestingly, all bacteria isolated and identified in this study were present in all treatments, including the control. / Environmental Sciences / M.Sc. (Environmental Sciences)
208

Integrated processes for removal of persistent organic pollutants : soil washing and electrochemical advanced oxidation processes combined to a possible biological post-treatment

Mousset, Emmanuel, Mousset, Emmanuel 02 December 2013 (has links) (PDF)
Soils contaminated by hydrophobic organic pollutants like polycyclic aromatic hydrocarbons (PAHs) are a common concern since they are extremely difficult to remove and their potential toxicological impacts are significant. As an alternative to traditional thermal or physical treatments, soil washing and soil flushing processes appear to be conceivable and efficient approaches, especially for higher level of pollution. However, the treatment of highly loaded soil washing/flushing solutions is another challenge to overcome. In that way, a new integrated approach is suggested: soil washing/flushing processes combined to an electrochemical advanced oxidation process (EAOP) in a combination with a recirculation loop (to save extracting agents) and/or a biological post-treatment step (to minimize energy cost).Extraction efficiency of the extracting agent like hydroxypropyl-beta-cyclodextrin (HPCD) is compared to the traditional non-ionic surfactant Tween 80 in synthetic and real soil washing solutions. A new simple fluorescent sensitive and selective quantification method is developed to monitor Tween 80 oxidation. Two EAOPs were compared: electro-Fenton (EF) and anodic oxidation (AO). Platinum (Pt) (in EF process) and boron doped diamond (BDD) (in both treatment) anodes are the respective electrodes employed to recycle effluents and to consider a biological post-treatment, respectively. Regarding the extracting agent recovery, the biodegradability evolution of effluent and the energy consumption (in kWh (kgTOC)-1) during EAOP, HPCD is more advantageous than Tween 80. However, in terms of extraction efficiency, costs of extracting agents and impact on soil respirometry, Tween 80 is much more efficient. By considering all these advantages and drawbacks, Tween 80 could still appear to be the best option
209

Etude expérimentale de la dégradation hétérogène des Composés Aromatiques Polycycliques (CAP) d'intérêt troposphérique

Miet, Killian 05 December 2008 (has links)
Ce travail a eu pour objectif d’étudier l’oxydation hétérogène de composés aromatiques polycycliques (CAP) adsorbés sur des particules solides, exposés à des oxydants troposphériques. Après adaptation et validation des protocoles analytiques, deux aspects ont été abordés : les cinétiques de dégradation avec O3, NO2 et OH dans un premier temps, puis l’étude des produits d’oxydation formés au cours de ces réactions. Les constantes de vitesse mesurées ont permis de comparer les différences de réactivité entre les composés étudiés (pyrène, 1-nitropyrène, 1-hydroxypyrène, 9,10-anthraquinone). L’influence de différents paramètres sur la réactivité (nature des particules, concentration en HAP…) a aussi été étudiée. Enfin, la détermination des produits d’oxydation et leur quantification, quand cela a été possible, a permis de mieux comprendre le devenir de ces composés particulaires dans l’atmosphère, à travers les mécanismes réactionnels proposés. / This work deals with the study of the atmospheric heterogeneous oxidation of polycyclic aromatic compounds (PACs) adsorbed on particles. After the development and the validation of the different analytical procedures, degradation kinetics and oxidation products were investigated for the reactions of NO2, OH and O3 with pyrene, 1-nitropyrene, 1-hydroxypyrene and 9,10-anthraquinone. The measured rate constants allowed to compare the reactivity of the different compounds. The influence of some parameters on the reactivity (nature of particles, PAC concentration…) has also been studied. Finally, the corresponding oxidation products were also measured, and quantified when possible, allowing to a better understanding of the fate of particulate PACs in the atmosphere, through the proposed chemical mechanisms.
210

Développements méthodologiques pour l’extraction et l’analyse des polluants organiques d’intérêt pour l’environnement marin : application aux hydrocarbures aromatiques polycycliques

Kanan, Rami 20 December 2012 (has links)
La présence d’hydrocarbures dans l’environnement que ce soit suite à un déversement accidentel de pétrole en mer ou suite à des apports chroniques, est une préoccupation majeure en raison de leur écotoxicité et de leur potentiel à être bioaccumulés, et ainsi, pénétrer la chaîne alimentaire. Par conséquent, ces molécules sont sous haute surveillance et il est nécessaire de disposer de méthodes analytiques permettant de les identifier et de les quantifier, et ceci, pour des concentrations allant du mg/L au ng/L. Cependant et dans la plupart des cas, les analyses en laboratoire des hydrocarbures, notamment aromatiques, se limitent à la quantification des 16 hydrocarbures aromatiques polycycliques (HAP) identifiés par l’Agence américaine de Protection Environnementale (US-EPA) comme étant dangereux pour l’environnement du fait de leur caractère cancérigène. Or, les hydrocarbures aromatiques polycycliques soufrés (HAPS) ainsi que leurs homologues substitués sont, sur le plan chimique, structurellement proches des HAP, et peuvent donc présenter des risques environnementaux similaires, à savoir être cancérigènes ou mutagènes. Le travail de recherche réalisé s’inscrit dans ce contexte avec pour objectif des développements méthodologiques permettant l’extraction et l’analyse d’une gamme plus large de HAP, des HAPS et leurs dérivés alkylés directement dans les produits pétroliers ou dissous en phase aqueuse. Des protocoles d’extraction par "stir bar sorptive extraction" (SBSE) et par microextraction sur phase solide (SPME), et des méthodes d’analyse par chromatographie en phase gazeuse couplée à la spectrométrie de masse simple (GC-MS) et en tandem (GC-MS-MS) ont été développés. Les résultats obtenus plaident en faveur de ces méthodologies aussi bien en termes de linéarité de la réponse qu’en termes de sensibilité, méthodologies qui ont été appliquées avec succès pour la détermination des analytes d’intérêt dans des fractions solubles préparées au laboratoire (WAF et WSF). Pour la CG-MS-MS, si elle se révèle particulièrement adaptée car elle apporte un degré de certitude élevé, elle n’en reste pas moins une technique délicate à mettre en oeuvre, notamment dans le cas des composés alkylés pour lesquels des solutions étalons ne sont pas disponibles. Pour pallier cette difficulté, un produit de référence contenant l’ensemble des analytes d’intérêt a été caractérisé. Pour les composés alkylés non disponibles commercialement, des appro-ximations ont été effectuées par MS simple en se basant sur une analyse comparée des coefficients de réponse en mode MRM et SIM. La méthodologie ainsi mise au point a permis de caractériser le fioul de l’Erika avec une faible variabilité des résultats. Ce produit peut servir de référence pour l’analyse quantitative de l’ensemble des familles de composés identifiés dans cette étude. / The presence of hydrocarbons in the environment either as a result of oil spills at sea or due to chronic discharge is a major concern because of their ecotoxicity and their potential to bioaccumulate and thus enter the food chain. Therefore, these molecules are closely monitored and reliable analytical methods are required to identify and quantify them, for concentrations ranging from mg/L to ng/L. However, in most cases, laboratory analyses of hydrocarbons, especially aromatic hydrocarbons, are limited to the quantification of 16 polycyclic aromatic hydrocarbons (PAHs) identified by the U.S. Environmental Protection Agency (U.S. EPA) as hazardous to the environment due to their carcinogenic nature. However, polycyclic aromatic sulphur heterocycles (PASHs) and their substituted homologs are, in chemical terms, structurally similar to PAHs, and therefore can pose similar environmental risks, i.e. they can be carcinogenic or mutagenic. In this context, the research work carried out aims to develop methodologies for the extraction and analysis of a wider range of PAHs, PASHs and their alkyl derivatives directly in oil or dissolved in the aqueous phase. Extraction protocols by stir bar sorptive extraction (SBSE) and solid phase microextraction (SPME), and methods of analysis by gas chromatography coupled with mass spectrometry (GC-MS) and with tandem mass spectrometry (GC-MS-MS) have been developed. The results argue in favor of these methodologies both in terms of linearity of the response and in terms of sensitivity. These methodologies that have been successfully applied for the determination of analytes of interest in the water accommodated fraction and water soluble fraction prepared in the laboratory (WAF and WSF). For GC-MS-MS, while it is particularly suitable because it provides an additional level of selectivity, it is a difficult technique to implement, in particular in the case of molecules for which no calibration solutions are available. To overcome this difficulty, a reference oil containing all the target molecules was characterized. For alkylated compounds that are not commercially available, approximations were made by simple MS, based on comparative analysis of response coefficients in MRM (Multiple Reaction Monitoring) and SIM (Single Ion Monitoring) modes. The finalized method was used to characterize the Erika fuel oil, with low variability in the results. This product can be used as a reference for the quantitative analysis of all the families of molecules identified in this study.

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