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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.
11

Occurrence, fate and effects of selected pharmaceuticals in sewage treatment plants.

January 2011 (has links)
Guan, Lijie. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2011. / Includes bibliographical references (leaves 139-161). / Abstracts in English and Chinese. / Acknowledgements --- p.i / Table of contents --- p.vii / List of Figures --- p.X / List of Tables --- p.xiii / Abbreviations --- p.xiv / Chapter 1. --- INTRODUCTION --- p.1 / Chapter 1.1 --- Source and Fate of Pharmaceuticals in the Environment --- p.1 / Chapter 1.2 --- Occurrence of Pharmaceuticals --- p.2 / Chapter 1.2.1 --- Wastewater --- p.2 / Chapter 1.2.2 --- Sewage sludge and soil --- p.5 / Chapter 1.2.3 --- "Surface water, ground water and seawater" --- p.6 / Chapter 1.2.4 --- Drinking water --- p.9 / Chapter 1.3 --- Effects on the Environment --- p.11 / Chapter 1.3.1 --- Antibiotic resistance --- p.11 / Chapter 1.3.2 --- Ecotoxicity on the aquatic organisms --- p.14 / Chapter 1.4 --- Removal in the Environment --- p.19 / Chapter 1.4.1 --- Adsorption --- p.20 / Chapter 1.4.2 --- Photodegradation and hydrolysis --- p.22 / Chapter 1.4.3 --- Biodegradation --- p.23 / Chapter 1.5 --- Analytical Method of Pharmaceuticals in Environmental Samples --- p.25 / Chapter 1.5.1 --- Solid-phase extraction --- p.25 / Chapter 1.5.2 --- Liquid chromatography mass spectrometry --- p.30 / Chapter 1.6 --- Objectives and Outline of Thesis --- p.33 / Chapter 2 --- OCCURRENCE AND FATE OF SELECTED PHARMCEUTICALS IN STPS --- p.35 / Chapter 2.1 --- Introduction --- p.35 / Chapter 2.2 --- Materials and Methods --- p.36 / Chapter 2.2.1 --- Choice of pharmaceuticals for study --- p.36 / Chapter 2.2.2 --- Description of sewage treatment plants (STPs) --- p.41 / Chapter 2.2.3 --- Experimental approach --- p.49 / Chapter 2.3 --- Results and Discussion --- p.55 / Chapter 2.3.1 --- Occurrence of azithromycin --- p.55 / Chapter 2.3.2 --- Fate of azithromycin --- p.59 / Chapter 2.3.3 --- Occurrence of erythromycin --- p.63 / Chapter 2.3.4 --- Fate of erythromycin --- p.67 / Chapter 2.3.5 --- Occurrence of roxithromycin --- p.70 / Chapter 2.3.6 --- Fate of roxithromycin --- p.74 / Chapter 2.3.7 --- Occurrence of atenolol --- p.75 / Chapter 2.3.8 --- Fate of atenolol --- p.79 / Chapter 2.3.9 --- Occurrence of simvastatin --- p.81 / Chapter 2.3.10 --- Fate of simvastatin --- p.84 / Chapter 2.3.11 --- Fate of pharmaceuticals during different treatment process --- p.85 / Chapter 2.3.12 --- Contribution of industrial (manufacturing) plants to STPs --- p.87 / Chapter 2.3.13 --- Seasonal variation --- p.87 / Chapter 2.4 --- Summary --- p.90 / Chapter 3 --- EFFECTS OF PHARMACEUTICALS ON ACTIVATED SLUDGE BACTERIA --- p.91 / Chapter 3.1 --- Introduction --- p.91 / Chapter 3.2 --- Materials and Methods --- p.92 / Chapter 3.2.1 --- Growth inhibition test --- p.92 / Chapter 3.2.2 --- Nitrification inhibition test --- p.94 / Chapter 3.3 --- Results and Discussion --- p.96 / Chapter 3.3.1 --- Growth inhibition of activated sludge bacteria --- p.96 / Chapter 3.3.2 --- Inhibition of nitrifying bacteria --- p.102 / Chapter 4 --- BIODEGRADATION PATHWAYS OF FOUR PHARMACEUTICALS --- p.106 / Chapter 4.1 --- Introduction --- p.106 / Chapter 4.2 --- Materials and Methods --- p.107 / Chapter 4.2.1 --- Test procedures --- p.107 / Chapter 4.2.2 --- Detection method --- p.108 / Chapter 4.3 --- Results and Discussion --- p.109 / Chapter 4.3.1 --- Degradation of atenolol --- p.109 / Chapter 4.3.2 --- Degradation of azithromycin --- p.117 / Chapter 4.3.3 --- Degradation of erythromycin --- p.129 / Chapter 4.3.4 --- Degradation of roxithromycin --- p.133 / Chapter 4.4 --- Summary --- p.134 / Chapter 5 --- GENERAL CONCLUSIONS --- p.136 / References --- p.139
12

The efficiency of constructed wetlands for the removal of the antimicrobial agent triclosan from wastewater

Zinn, Elizabeth R. 15 December 2012 (has links)
Access to abstract restricted until December 2014. / Review of relevant literature -- Efficiency of constructed wetlands to remove an antimicrobial agent triclosan from wastewater -- The removal of triclosan from laboratory scale constructed wetlands with four species of wetland plants -- Additional research : determination of the hydraulic retention time in an operational subsurface constructed wetland -- Additional research methods : the evaluation of the subsurface constructed wetland for the treatment of iron, phosphorus, ammonia, nitrite, nitrate, dissolved oxygen, pH and E. coli. / Access to thesis restricted until December 2014 / Department of Natural Resources and Environmental Management
13

Perfluorinated compounds, bishenol a and acetaminophen in selected waste water treatment plants in and around Cape Town, South Africa

Adeleye, Adeola Patience January 2016 (has links)
Thesis (MTech (Chemistry))--Cape Peninsula University of Technology, 2016. / The release of wastewater to the aquatic environment is most likely to introduce some trace levels of organic contaminants, some of which may be toxic, carcinogenic, or endocrine disruptors, as well as, persistent in the environment. Additionally, increasing contamination of surface waters by wastewater effluents has made water treatment processes more challenging and expensive. The presence of these pollutants in the receiving water body may have negative effects on aquatic species and often pose potential human health risks through the reuse of treated wastewater for drinking purposes and other household use. In countries like South Africa, Namibia, USA, Singapore and Australia, water agencies are intensifying wastewater reclamation/wastewater reuse as part of their water resource agenda: in order to meet the demands of the growing populations. Nowadays, water reuse is generally considered as a viable method of water supply management. This study focused on the identification of the occurrence, quantification of emerging contaminants and evaluation of removal efficiency in wastewater treatment processes of three classes of emerging contaminants (ECs) in wastewater: 1) six types of perfluorinated compounds (PFCs), namely; perfluorooctanoic acid (PFOA), Perfluorooctane sulphonate (PFOS), perfluoroheptanoic acid (PFHpA), perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), and perfluoroundecanoic acid (PFUDA); 2) bisphenol A (BPA); and 3) Acetaminophen (ACP). These contaminants were identified and quantified in four wastewater treatment plants in the Western Cape. These treatment plants include three WWTPs in Cape Town, namely: Bellville WWTP, Scottsdene WWTP and Zandvliet WWTP and one WWTP in the central Karoo (Beaufort West wastewater reclamation plant).
14

Microbial Structure- and Function-based Assessment of the Performance and Metabolic Versatility of Biological Nutrient Removal Systems

Hoar, Catherine January 2020 (has links)
Biological nutrient removal (BNR) systems employ engineered biological processes—including nitrification, denitrification, and biological phosphorus removal—to remove nutrients from wastewater. Since their original implementation, BNR systems have adapted to challenges, such as the presence of inhibitory compounds and demands for more energy- and resource-efficient wastewater treatment. Advancements in alternative BNR technologies made in response to these demands have highlighted the metabolic versatility of microbial communities present in BNR systems. This versatility is also observed in the expanded capacity of BNR systems to remove not only human-derived carbon, but also complex trace organic emerging contaminants (ECs). Based on conventional monitoring alone, the roles of specific bacteria and metabolic mechanisms in the removal of nutrients and ECs remain unclear. A detailed understanding of the actors and mechanisms in BNR systems can be attained through application of molecular biology tools, including those targeting community (a) structure and potential function through DNA analysis and (b) extant function through RNA analysis. This dissertation encompasses three objectives, which seek to link detailed molecular-level information to the performance and metabolic versatility of several nutrient-removing communities. The first objective was to assess the utility of gene expression assays to indicate and predict nitrification inhibition by toxic heavy metals based on functional responses of nitrifying bacteria. Through this assessment, it was found that genes related to both catabolic and anabolic pathways could be used as indicators of nitrification inhibition. The second objective was to investigate the effects of reactor operating conditions on simultaneous nitrogen and phosphorus removal by examining the microbial community structure and metabolism of a survey of full-scale BNR systems. A variety of BNR configurations and operating conditions, all capable of sustained nutrient removal, selected for different nitrogen- and phosphorus-removing communities. The activity of these communities was also dependent on configuration and operating conditions, as indicated by analysis of gene expression. Finally, the third objective was to examine the expanded capacity of BNR systems to attenuate ECs by investigating the removal of the EC bisphenol A (BPA) by microbial communities involved in nutrient removal. Communities derived from both full-scale and lab-scale systems were capable of biodegrading BPA, though each community was uniquely influenced by reactor processes and BPA exposure conditions. Results from this work also offered insights into the utility of assessed genes as biomarkers for metabolic activity and the importance of accurately characterizing in-situ responses of BNR systems. In both lab-scale and full-scale studies, certain genes demonstrated increased sensitivity to nutrient-removing activity. At lab-scale, observed differences between inhibition of ammonia oxidation through discrete and continuous Cu(II) exposure indicated that conventional short-term, ex-situ batch assays may underestimate inhibition in a parent reactor of interest. The benefit of gene expression assays to accurately reflect in-situ responses was also examined in full-scale BNR systems removing both nitrogen and phosphorus. Findings from full-scale BNR systems revealed the long-term effects of changes to process configurations on microbial community structure and activity. Despite differences in operating conditions and the resulting nitrogen- and phosphorus-removing communities, a variety of configurations sustained nutrient removal. Long-term effects were also characterized in the context of EC removal. Differences in BPA degradation rates and microbial community profiles in lab-scale mixed culture communities after extended BPA exposure showed the lasting influence of both reactor processes and BPA exposure conditions. Assessment of microbial community structure was also used to identify BPA-degrading bacteria. Results from each of the three objectives could be used in the development of biomarkers to assess and predict (1) process upsets or inhibition, (2) nutrient removal process performance, or (3) capacity for EC removal. Integrating analysis of microbial community structure and function with reactor performance monitoring and mechanistic modeling that includes such advanced knowledge holds the potential to not only guide effective operation of BNR systems, but also identify opportunities for more efficient and even concomitant nitrogen, phosphorus, and EC removal.
15

Abordagem metodológica para a valuação do petencial desregulador endócrino de água de beber: estudo com amostras reais / A methodological aprroch to evaluate endocrine disrupting activity of drinking water: real samples study in rats

Solano, Marize de Lourdes Marzo [UNESP] 10 February 2014 (has links) (PDF)
Made available in DSpace on 2015-05-14T16:53:22Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-02-10Bitstream added on 2015-05-14T16:58:55Z : No. of bitstreams: 1 000829087.pdf: 399761 bytes, checksum: 6162c9ec05a5f035f48858f6dc7daf87 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / If contaminated waters are treated by conventional processes (WTP) emerging contaminants are not fully removed and will remain in the drinking water (DW). We investigated the potential for endocrine disruption of two DW samples collected in 2010 and 2012 from a WTP located in São Paulo, Brazil. Water samples were extracted and chemically analyzed for emerging substances and evaluated with an in vitro bioluminescent yeast assay containing estrogen/androgen human receptors (BLYES/BLYAS). In vivo assays were conducted with 21-day old female rats exposed to DW extracts for 03 (uterotrophic assay; OECD) or 20-days (pubertal assay, EPA). The exposure represented a daily ingestion of 2 L, 5 L and 10 L of DW by a 60 kg human being. Caffeine (5.8 - 21 ug/L), estrone (1 ng/L), atrazine (2.2 -11.2 ng/L), carbendazim (0.22 ng/L), azoxistrobina (0.23 ng/L) and tebuconazole (0.19 ng/L) were detected in DW by LC-MS/MS-ESI. There were no increase of the uterus wet weight in the uterotrophic assay, and no alteration of the vaginal opening moment in the pubertal assay. However, there was increased relative blotted uterus weight in animals treated for 3-days with both DW. Levels of LH and FSH presented a significant dose-response increase in the uterotrophic assay developed with the 2010 sample. This happened in association with a significantly increased incidence of vaginal keratinization after the 3-day exposure. Results suggest the DW tested exerted hypothalamic-hypofisis activity alteration in vivo. Additional end-points in standard protocols could be useful to evaluate the presence of endocrine disruptor activity in DW
16

Abordagem metodológica para avaliação do potencial desregulador endócrino de água de beber : estudo com amostras reais /

Solano, Marize de Lourdes Marzo. January 2014 (has links)
Orientador: João Lauro Viana de Camargo / Coorientador: Gisela de Aragão Umbuzeiro / Banca: Ione Pellegatti Lemonica / Banca: Patrícia Carvalho Garcia / Banca: Anderson Joel Martino Andrade / Banca: Daniela Cristina Ceccatto Gerardin / Resumo: Não disponível / Abstract: If contaminated waters are treated by conventional processes (WTP) emerging contaminants are not fully removed and will remain in the drinking water (DW). We investigated the potential for endocrine disruption of two DW samples collected in 2010 and 2012 from a WTP located in São Paulo, Brazil. Water samples were extracted and chemically analyzed for emerging substances and evaluated with an in vitro bioluminescent yeast assay containing estrogen/androgen human receptors (BLYES/BLYAS). In vivo assays were conducted with 21-day old female rats exposed to DW extracts for 03 (uterotrophic assay; OECD) or 20-days (pubertal assay, EPA). The exposure represented a daily ingestion of 2 L, 5 L and 10 L of DW by a 60 kg human being. Caffeine (5.8 - 21 ug/L), estrone (1 ng/L), atrazine (2.2 -11.2 ng/L), carbendazim (0.22 ng/L), azoxistrobina (0.23 ng/L) and tebuconazole (0.19 ng/L) were detected in DW by LC-MS/MS-ESI. There were no increase of the uterus wet weight in the uterotrophic assay, and no alteration of the vaginal opening moment in the pubertal assay. However, there was increased relative blotted uterus weight in animals treated for 3-days with both DW. Levels of LH and FSH presented a significant dose-response increase in the uterotrophic assay developed with the 2010 sample. This happened in association with a significantly increased incidence of vaginal keratinization after the 3-day exposure. Results suggest the DW tested exerted hypothalamic-hypofisis activity alteration in vivo. Additional end-points in standard protocols could be useful to evaluate the presence of endocrine disruptor activity in DW / Doutor
17

Probing the environmental fate of emerging contaminants and their ecological impacts on aquatic environment

Sang, Ziye 23 June 2016 (has links)
In recent years, new classes of aquatic pollutants have received growing concerns from the environmentalists due to their unclear effects and increasing release into the water environment. Generally, before entering the aquatic ecosystem, many of these emerging contaminants are deemed safe active ingredients in the commercial products. This may lead to the underestimation of their potential impacts to the environment, once these substances were drained into the natural waters. So far, a wide range of emerging contaminants are still not well studied. In this thesis work, the environmental behaviors for two typical groups of emerging contaminants, which are frequently used in personal care products, are systematically probed in the aquatic ecosystem. One is the hydrophilic compounds - artificial sweeteners and the other one is the moderate hydrophobic compounds - ultraviolet (UV) filters. Acesulfame and sucralose are two of the most commonly used artificial sweeteners, which are a newly recognized class of emerging contaminants due to their widespread occurrence and extreme persistence in water environment. To date, however, their environmental behaviors, fates as well as long term ecotoxicological contributions in our water resources still remain largely unknown. In this work, a photodegradation investigation with UV/TiO2 was performed on these two artificial sweeteners, which projected their potential impacts under prolonged exposure to intensive solar irradiation. Real-time observation of the degradation profiles in both sweeteners illustrated that formation of new photo by-products under prolonged UV irradiation is highly viable. For the first time, acute toxicity for the degradates of these two sweeteners were measured and the enhancement in their ecotoxicity has been observed during the irradiation. In an attempt to neutralize this prolonged environmental threat, the feasibility of UV/TiO2 as an effective mineralization process in wastewater treatment was evaluated for both sweeteners. As a result, relatively higher removal efficiencies for acesulfame and sucralose were achieved in this study. For UV filters, a comprehensive investigation on their environmental behaviors and impacts was described in this thesis, covering the occurrence study in surface water and biota, environmental fate and their ecological risks. In the first step, an analytical method based on ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was developed for the simultaneous determination of twelve UV filters in the environmental waters, which achieved good sensitivity to sub-ng/L levels. To monitoring their occurrence in local marine environment, the regional distribution of these sunscreen compounds was monitored along the coastline of Hong Kong. At the same time, considering the intensive consumption of sunscreen products in hot weathers, seasonal variation of UV filters between summer and winter was taken into consideration in our occurrence study. Additionally, we also monitored their occurrence in the drinking water supply system of Hong Kong, including the source water in Dongjiang, raw water in local reservoirs and tap water collected from urban communities, to support a good management on the reliable water supply. Furthermore, the distribution results indicated that the incomplete removal of UV filters in the effluents could be a major source for their release into the environmental waters. Aiming to achieve the complete removal of such compounds, a powerful technique of ozonation was employed in this study and the preliminary operational conditions were further provided. Secondly, in order to gain a better understanding of their environmental fate in surface water, a simulative catalytic photodegradation study with UV/TiO2 were performed to investigate the photostability, phototoxicity and the transformation pathways of seven selected UV filters. During the photodegradation, several transformation products were primarily identified. Thirdly, since lipophilic sunscreens were easily accumulated in the biota, we also made efforts to monitor their occurrence in marine organisms of different species, including farmed fish, wild mussels, prawns and sea urchin, which were collected from local offshore areas. Last but not the least, according to the measured concentrations of UV filters in Hong Kong marine environment, we further performed the ecological risk assessment with the approach specific to the marine aquatic compartment, so as to provide the overall understanding on the environmental impacts of these UV filters.
18

Synchoronised physical, chemical and microbial analysis of wastewater from University of Limpopo food- court

Rapeta, Mokgadi Gladness January 2021 (has links)
Thesis (M.Sc. (Chemistry)) -- University of Limpopo, 2021 / The present research work deals with the study of some of the important physicochemical parameters of restaurant wastewater effluents collected from Mankweng business centre along the University of Limpopo road. Studies revealed that restaurants, food preparation facilities, engineering, paper mill, fine chemical, dyes, paint, pharmaceutical, petrochemical and textile industries are some of the major industries responsible for polluting the aquatic environments. This research attempts to review the physical, chemical, and microbial analysis of wastewater from food service establishments (FSEs) and extraction of fats, oil, and grease (FOG) and its characterization using different analytical techniques. The elemental analysis revealed that the concentration of elements such as zinc, lead and manganese were 6.44 mg/L, 0.02 mg/L and 0.53 mg/L, respectively. The concentration of these elements was above the required South African National Standards 241 (SANS241) limit, that is, ≤5mg/L, ≤0.01mg/L and ≤0.4mg/L for Zn, Pb and Mn, respectively. The elevated concentrations may be due to corrosion, acidic pH found in some samples and high organic load. High organic content in wastewater influenced the production of oxygen by microorganisms in-order to degrade the amount of waste in the wastewater and this has led to high chemical oxygen demand (COD) level ranging from 1784-7196 mg/L and biochemical oxygen demand (BOD5) from 1101.32 to 3222.32 mg/L. The study has demonstrated that the wastewater samples are contaminated with faecal coliforms because the concentration of microbes Escherichia Coli (E.coli) with a Most Probable Number (MPN) >200.5 in most samples, P. aeruginosa, Pseudomonas spp. were too numerous to count (TNC) and total coliforms at the highest concentration of 9.1x103 CFU/ml which was influenced by change in pH of the wastewater, the FOG content consists of both triglycerides and acrolein. The overall results highlight the discharge of highly polluted wastewater effluent, these FSE have resulted in pollution of nearby rivers thereby affecting the growth of vegetation and aquatic life. The results of the present investigation point out the need to implement common objectives, compatible policies, and programmes for improvement in the FSEs wastewater treatment methods. / National Research Foundation and Sasol-Inzalo Foundation
19

On the derivation of Water and Sediment Quality Guidelines: some pressing issues and theirresolutions

Kwok, Wing-hin, Kevin Patrick., 郭穎軒. January 2009 (has links)
published_or_final_version / Biological Sciences / Doctoral / Doctor of Philosophy
20

Abundance of nonprescription pharmaceuticals in central Indiana streams and effects on sediment microbial activity

Bunch, Aubrey R. January 2009 (has links)
Access to abstract permanently restricted to Ball State community only / Indirect effects of human population growth on stream ecosystem function : sediment respiration and nutrient uptake response to nonprescription pharmaceuticals -- Frequency and distribution of nonprescription pharmaceuticals in central Indiana streams. / Access to thesis permanently restricted to Ball State community only / Department of Biology

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