الفهرس 
AbstractOnly 14 pages are availabe for public view
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Abstract
The environmental problems arising from emerging contaminants (ECs) have recently grown causing adverse effects to animals and humans. However, monitoring and quantifying ECs is highly challenging for several reasons : (i) the bad impact of most of the developed analytical methods to the environment, and (ii) not all ECs are known until now. The first challenge could be overcome by developing green and miniaturized analytical methods using novel green solvents for targeted monitoring and quantifying certain classes of ECs in water. I investigated the effectiveness of deep eutectic solvent, DES (tetrabutylammonium bromide: acetic acid) as a novel green disperser for the enrichment of steroids in water for the first time. Using DES as disperser attaining a higher recovery than the conventional ones. In addition, novel ternary DESs were synthesized by combining various fatty acids at different ratios and applied for the enrichment of different endocrine disruptors from river water. Adding a third component to classical two-component eutectic solvents allows to purposefully control density, melting point, and viscosity of the synthesized solvents. Ternary solvents provided excellent extraction efficiency (90.06–104.43%) compared with other binary ones. After that, I investigated the efficacy of different monoterpenes as relatively green bio-based solvents for the extraction of different NSAIDs from water. Results indicated that D-limonene could extract the hydrophobic compounds with higher %recovery compared with other halogenated solvents. Consequently, D-limonene was proven to be a good alternative to highly toxic solvents for hydrophobic NSAIDs extraction from water. Also, another bio-based solvent (diethyl carbonate, DEC) was tested for the microextraction of PAHs from water and beverage when combined with μ-QuEChERS procedure. DEC is considered as biodegradable (with octanol/water coefficient < 3, resulting in low potential of bioaccumulation), classified as a green solvent and considered as one of the recommended solvent alternatives. The method could enrich PAHs up to 166-folds. Finally, the greenness of all of these procedures was assessed, proving their excellent greenness with lower impact to both operator and environment. The four developed green methods would have other broader implications for detecting other contaminants from water applying the novel green solvents. However, target analysis of ECs focuses mainly on monitoring a small number of ECs and by far do not cover the full range of ECs classes. Therefore, the second challenge, a comprehensive non-target screening is needed to identify additional ECs and assess new and emerging risks. Non-target analysis using high resolution accurate mass LC-QTOF/MS could achieve this objective. Hence, a novel UPLC/QTOF–MS-based non-targeted metabolomics, with MSn data acquired through data-independent acquisition (DIA) mode in combination with the multivariate analysis was developed to analyze the variation of contaminants between wastewater influents and effluents and thus assess the treatment efficiency. Dozens of compounds were tentatively identified and several of them were also confirmed with standard compounds. At last, a multivariate [unsupervised principal component analysis (PCA)] model was applied for discrimination analysis to assess the wastewater treatment efficiency, proving the high efficiency of water treatment for removing most of ECs. In summary, our findings could overcome the main points of challenges in the analysis of ECs in the environment by developing both targeted and untargeted analytical methods. Target analysis provide sustainable tools for a cleaver combination of environment-friendly and cheap methodology. While applying non-target analysis provides a way for monitoring and identifying other unknown ECs with highlighting new and emerging risks of those contaminants. This, in terms, could provide valuable information for other scientists to study the occurrence, fate, transport, ecotoxicology and health impact assessment of ECs on the environment.