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1

Law, Cheuk Fung Japhet. "Catalytic advanced oxidation processes for degradation of environmental emerging contaminants." HKBU Institutional Repository, 2019. https://repository.hkbu.edu.hk/etd_oa/610.

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In recent years, the increasing release of trace organic chemicals to the aquatic environment have been problematic to both the ecosystem and the human society. These trace organic chemicals, regarded as emerging contaminants, include different categories of chemicals, which are either deemed to be safe for human consumption or they are naturally occurring compounds. As a newly recognized class of emerging contaminant, artificial sweeteners are proven to be one of the most ubiquitous classes of emerging contaminants in environmental waters. Its transformation to different suite of TPs during water treatment processes generated more toxic influence than the parent compound is problematic. The realization of the widespread of emerging contaminants, together with their ambiguous fate and impact to the environment have led to the development of advanced oxidation processes that can effectively attenuate this wide range of contaminants. In this work, several catalytic advanced oxidation processes were studied. On one hand, it aimed to evaluate their effectiveness on the removal of the artificial sweetener - acesulfame; and on the other hand, to shed lights on the future development of catalytic advanced oxidation processes. In the first part of this thesis, the photo-Fenton treatment was evaluated on its potential to effectively remove acesulfame together with the produced transformation products, and the post-treatment toxicity screening. The photo-Fenton treatment was found to be effective in removing both the parent compound and the transformation products, without leading to an increase in toxicity, which is largely related to the effective removal of the transformation products. In attempt to reduce the reliance on UV irradiation, newly synthesized carbon and nitrogen co-doped TiO2-based photocatalyst was applied to capture the simulated sunlight for the degradation of acesulfame. The heterogenous photocatalytic treatment was found to involve several different oxidative reactive species for both degradation and transformation by using several scavengers to alter the degradation profile. Unexpected transformation product was also formed upon treatment in actual water matrix, suggesting the impact of water constituents to the transformation of emerging contaminants. Toxicity results indicated the inability to achieve detoxification, suggesting that a more effective degradation process was needed. To accelerate the degradation process, and enhance the performance at neutral pH, the use of redox mediators for Fenton/Fenton-like system was evaluated. Developed novel Fenton-like system involving copper(II) as transition metal ion, persulfate as oxidant and mercaptosuccinic acid as redox mediator led to effective removal of different contaminants. Elucidation of the proposed oxidation mechanism suggested the role of each components of the system, and the generation of different reactive species for degradation as indicated by the different acesulfame transformation profile obtained. The implementation of redox mediators to Fenton/Fenton-like system was beneficial and an effective approach. In short, this work presents several kinds of catalytic advanced oxidation process and shed lights on improving the degradation performance with directions for the future development of better and more effective water treatment processes.
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2

Jiang, Yanan. "Emerging contaminants : environmental fate of artifical sweeteners." HKBU Institutional Repository, 2013. http://repository.hkbu.edu.hk/etd_ra/1508.

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3

Janna, Hussein. "Occurrence and removal of emerging contaminants in wastewaters." Thesis, Brunel University, 2011. http://bura.brunel.ac.uk/handle/2438/6097.

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Over the past decade, the occurrence and removal of emerging contaminants in the environment has received much attention. Both natural and synthetic progestogens, which are hormones, and also benzotriazoles are two examples of such emerging contaminants. Sewage treatment works are recognised as one of the main routes of these compounds to the environment. Low concentrations (nanograms per litre) of biologically active chemicals may exhibit an impact on aquatic organisms and human health. This study was undertaken to determine the occurrence and removal of these two classes of chemicals at sewage treatment works, along with an evaluation of the performance of advanced treatment and also to investigate their fate in the aquatic environment. Therefore, field-based sampling campaigns were undertaken at a sewage treatment works, rivers and potable water to achieve these aims. Solid phase extraction and LC/MS/MS were used in order to analyse the samples from these different locations, along with catchment modelling and assessment of how the use of benzotriazoles may contribute to their presence in the environment. The results have demonstrated that progestogens and benzotriazoles are in the sewage system; the natural hormone (progesterone) was the most predominant compound entering the sewage treatment work (46.9 ng/l) among the progestogens while concentrations of the benzotriazoles were two orders of magnitude higher than the progestogens. The conventional sewage treatment works were, to some extent, able to remove these compounds from wastewaters. However, this may not be adequate to afford protection to the environment. The investigation of advanced treatments, ozone, granular activated carbon and chlorine dioxide, indicated no further significant removal of progestogens, probably as a result of concentrations being close to method detection limits. However, there were indications that benzotriazoles were removed. A degradation study demonstrated that the natural hormone (progesterone) was degraded rapidly while benzotriazoles were not degraded. Catchment modelling indicated that high (up to 2,000 ng/l) concentrations of benzotriazoles would be present in surface waters used for potable supply, and consequently benzotriazoles were found in the tap water with mean concentrations of 30.9 ng/l (benzotriazole) and 15.1 ng/l for tolyltriazole. It is therefore apparent that although conventional treatment may be seen as effective, achieving over 90% removal, this may not be good enough. However, before investing in tertiary treatment, a number of factors, such as the effectiveness at different sites, the presence of degradation products and costs, both financial and in relation to energy use, need to be considered.
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4

Vesely, William C. "Emerging Contaminants: Occurrence of ECs in Two Virginia Counties Private Well Water Supplies and Their Removal from Secondary Wastewater Effluent." Thesis, Virginia Tech, 2018. http://hdl.handle.net/10919/83829.

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Emerging contaminants (ECs) are chemicals such as pharmaceuticals and personal care products that have been detected in various environmental matrices, including drinking water supplies at trace concentrations (ng/L-ug/L or ng/kg-ug/kg). Current wastewater treatment plant technology is largely ineffective at removing ECs. The objectives of this investigation were to: 1) determine the occurrence of ECs in private well water supplies in Montgomery and Roanoke County, VA 2) quantify the concentrations of three ECs in selected private water supplies; 3) examine the relationship between water quality constituents (nitrate, bacteria, pH and total dissolved solids) to EC occurrence in private water supplies; and 4) determine the ability of the MicroEvapTM, a novel wastewater treatment technology, to remove ECs from secondary wastewater effluent. In partnership with the Virginia Household Water Quality Program, 57 private water supplies were sampled and tested for the occurrence of 142 ECs and 43 other water quality constituents. Up to 73 ECs were detected in the sampled private water supplies. Higher numbers of ECs detected in the tested private water supplies were related with nitrate >1 mg/L, total dissolved solids >250 mg/L, and the presence of total coliform bacteria. Results indicate the MicroEvapTM technology had >99% removal effectiveness for all 26 tested ECs from three secondary wastewater effluent. With the increasing detection of ECs in water bodies, it is essential to understand the occurrence of ECs and environmental predictors of EC presence in different water matrices and continue to develop water treatment technology capable of treating wastewater for EC removal.
Master of Science
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5

Alvarez, Corena Jose Ricardo. "Heterogeneous Photocatalysis For The Treatment Of Contaminants Of Emerging Concern In Water." Digital WPI, 2015. https://digitalcommons.wpi.edu/etd-dissertations/320.

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"The simultaneous degradation of five organic contaminants: 1,4 dioxane, n-nitrosodimethylamine, tris-2-chloroethyl phosphate, gemfibrozil, and 17β estradiol, was investigated using a 1 L batch water-jacketed UV photoreactor utilizing titanium dioxide (TiO2) nanoparticles (Degussa P-25) as a photocatalyst. The primary objectives of this research were: (1) to experimentally assess the feasibility of heterogeneous photocatalysis as a promising alternative for the degradation of organic compounds in water; and (2) to model the chemical reactions by the application of two different approaches based on adsorption – surface reactions (Langmuir–Hinshelwood) and its simplification to a first order rate reaction. These objectives were motivated by the lack of information regarding simultaneous degradation of organic compounds in different categories as found in real aqueous matrices, and generation of specific intermediates that could eventually represent a potential risk to the environment. Contaminants were chosen based on their occurrence in water sources, their representativeness of individual sub-categories, and their importance as part of the CCL3 as potential contaminants to be regulated. Contaminant degradation was evaluated over time, and the TiO2 concentration and solution pH were varied under constant UV irradiation, oxygen delivery rate, mixing gradient, and temperature. 

 Specific accomplishments of this study were: (1) reaction kinetics data were obtained from the UV/TiO2 experiments and showed the potential that this UV/TiO2 process has for effectively removing different types of organic compounds from water; (2) a good fit was obtained between photocatalytic reaction kinetics models and the contaminant data using pseudo first-order and Langmuir-Hinshelwood (L-H) models; (3) results of the analytical methods developed in this study were validated by measurements performed by a certified laboratory; (4) the reaction kinetic parameters obtained in this study were normalized to electrical energy per order, reactor volume and surface area of the photocatalyst in order to provide rate constants with wider applicability for scale-up to more complex systems; and (5) degradation intermediates from the oxidation process and from interaction among compounds were identified and possible pathways for their formation suggested. This research has provided a better understanding of the photocatalytic process for the removal of organic contaminants from complex aqueous matrices."
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6

Bhattarai, Bikash. "Development of novel adsorbents for the removal of emerging contaminants from water." Master's thesis, Temple University Libraries, 2011. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/148072.

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Civil Engineering
M.S.E.
Emerging contaminants (ECs) such as estrogen hormones, perfluoro compounds (PFCs), bisphenol-A (BPA), and 1,4-dioxane have been detected in natural water at many places. The existing conventional wastewater treatment systems are not designed for the removal of these contaminants. This critical issue leads to the need for the development of advanced and effective technologies.β-cyclodextrin (β-CD) is a glucose-based molecule which has high affinity for different organic contaminants by the formation of host/guest inclusion complexes. In this research, water soluble β-CD was reacted with certain crosslinking agents and copolymers to form water insoluble β-CD and to coat β-CD onto silica particles. The development of such novel hybrid adsorbents provides high binding capacity with organic contaminants along with high mechanical strength. Three different approaches were used to develop adsorbents by using two crosslinking agents (epichlorohydrin (EPI) and hexamethylene diisocyanate (HMDI), two copolymers (glycidoxypropyl trimethoxysilane and aminopropyl triethoxysilane) and three solvents (NaOH, dimethyl formamide (DMF), and dimethyl sulfoxide (DMSO). The developed adsorbents were tested for the removal of ECs of interest (estrogens, PFCs, 1,4-dioxane, and BPA) under batch and column conditions from Milli-Q water. The adsorbent prepared by reacting β-CD with HMDI as crosslinking agent with the molar ratio of 1:8 showed best results in removing the target compounds. The adsorbent showed more than 95% removal of 17β-estradiol (in single component) and more than 90% of most of the estrogens (in multicomponent), more than 99% of PFOA, and a maximum of 90% removal in case of BPA. However, the developed adsorbent did not show any removal in case of 1,4-dioxane. The developed adsorbent showed a good regeneration capacity in removing PFOA over three successive cycles. The characterization of the adsorbents using FTIR, TGA, and TEM confirmed the coating of β-CD onto silica particles. The removal of ECs of interest was dependent on the nature of both adsorbents and adsorbates. The nature of adsorbent such as type of crossling agent, molar ratio between β-CD and crosslinking agents affect the removal of the contaminants. Similarly, the nature of adsorbates such as size, shape, and presence of functional groups affect the removal efficiency.
Temple University--Theses
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7

Upton, Ethan A. "Sinkhole Lake Infiltration of Contaminants of Emerging Concern from Onsite Water Treatment Systems." Scholar Commons, 2019. https://scholarcommons.usf.edu/etd/7977.

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The advancement in synthetic chemicals commonly referred to as contaminants of emerging concern (CECs) and their application has led to an increase in environmental pollution. The use of septic tanks otherwise referred to as onsite water treatment systems (OWTS), promotes the introduction of CECs into the environment while allowing little in the way of remediation. In order to study the impacts of CECs from OWTS as they infiltrate the environment and the aquifer system, water, sediment, and vegetation samples were collected around a sinkhole lake surrounded by residential housing using OWTSs. The main question of this research project is what is the fate of CECs from OWTSs effluent within the catchment of a sinkhole lake? Liquid chromatograph mass spectrometry was used to analyze the samples for the presence of CECs. It was found that the relative quantity of CECs in the individual constituents is dependent upon 1) the hydrophobicity and polarity of the individual compound, 2) the specific sampling site, 3) the topography gradient, and 4) for vegetation the connectedness of the sample type to the sediment. The implications derived from this study can be applied in environmental engineering, urban and suburban planning, environmental monitoring, and should be considered when residents use well water as their source of potable water.
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8

Bhattarai, Bikash. "DEVELOPMENT OF NOVEL ADSORBENTS FOR THE REMOVAL OF EMERGING CONTAMINANTS FROM WATER AND WASTEWATER." Diss., Temple University Libraries, 2015. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/332757.

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Civil Engineering
Ph.D.
There are many reports indicating the presence of various emerging contaminants (ECs) in treated wastewater and other water sources. The detection of such contaminants in the environment and the ability of these contaminants to pose potential threats to the environment at very low concentrations have led to a need for more efficient treatment technologies. Cyclodextrins (CDs) have gained significant interest as an alternative adsorbent for water and wastewater treatment because of their unique physico-chemical characteristics and excellent selectivity towards organic compounds. The property of CD to form inclusion complexes with various molecules through host-guest interactions has made it a useful compound for the removal of a number of contaminants from water and wastewater. The overall goal of the study is to identify and develop a novel adsorbent for the removal of ECs of interest. The specific objectives are a) to synthesize various beta-cyclodextrin (BCD) based adsorbents by coating BCD onto different supports such as silica, filter paper, iron oxide, and zeolite, b) to perform batch and column experiments using the developed adsorbents, c) to evaluate the performance of the adsorbents in different water matrices such as MQ water, simulated wastewater in presence of humic acid, and real municipal wastewater, d) to study the regeneration potential of the adsorbents. In this research, various (BCD) based hybrid adsorbents were synthesized and their performances were evaluated based on the removal of selected ECs. At first, chemically bonded BCD onto silica particles as hybrid adsorbents were synthesized by using crosslinking agents and copolymers. Three different methods were used to synthesize 14 different BCD coated silica adsorbents. The adsorbent prepared by reacting BCD with hexamethylene diisocyanate (HMDI) as crosslinking agent and dimethyl sulfoxide (DMSO) as solvent showed best results in removing the ECs studied. The adsorbent showed more than 95% removal of 17β-estradiol (in single component) and more than 90% of most of the estrogens (mixture of 12), more than 99% of perfluorooctanoic acid (PFOA) (in single component) and more than 90% of most of the PFCs (mixture of 10), and a maximum of 90% removal in case of BPA. The adsorption capacity of the developed adsorbent was observed to be higher for the removal of 17β-estradiol and PFOA than that of commercially available activated carbon (F400) in MQ water. In order to represent the real environmental scenario, further batch experiments were conducted for the removal of two PFCs (PFOA and PFOS (perfluorooctane sulfonic acid)), 17β-estradiol, and BPA at environmentally relevant concentrations from wastewater. The adsorbent was effective in removing the ECs that were spiked in the secondary effluent of a municipal wastewater treatment plant. Furthermore, the adsorbent was successfully regenerated with methanol over four cycles without significant loss in its adsorption capacity for the removal of PFOA and estrogens. Ozonation as an alternative method of regeneration was also used and the process was also very effective in regenerating the adsorbent over seven successive cycles for the removal of BPA and 17β-estradiol. The characterization of the adsorbents using FTIR, TGA, and TEM confirmed the coating of BCD onto silica particles. The TGA results showed high thermal stability of the adsorbent (upto 300oC). As an alternative to chemical impregnation, another method of synthesis was developed where various BCD based hybrid adsorbents were synthesized by physically impregnating hydroxypropyl BCD (hpBCD) polymer onto three different supports: iron oxides, zeolite, and filter paper. The hpBCD impregnated filter papers were synthesized by solvent evaporation method and different adsorbents were synthesized by varying the polymer loadings. The polymer loading was optimized based on the performance of the modified (polymer impregnated) filter paper in terms of its filtration capacity as well as adsorption capacity to remove PFOA and BPA. The magnetic adsorbent was prepared by mixing hpBCD polymer with iron oxide (Fe3O4) particles. It was observed that by increasing the mixing time of the support (Fe3O4) with the polymer from 48 to 96 hr, the adsorption capacity of the adsorbent (hpBCD polymer coated Fe3O4) could be significantly enhanced. The same approach was also used to synthesize hpBCD polymer coated zeolite adsorbent and both adsorbents (hpBCD/zeolite and hpBCD/Fe3O4) were effective in removing the selected ECs from MQ water, simulated water, and wastewater.
Temple University--Theses
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Jiang, Wenting, and 江文婷. "A systematic review of the cancer risks and industrial contamination in freshwater resources in China." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2013. http://hdl.handle.net/10722/193825.

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Objectives To evaluate the association between exposures to the main chemical contaminants released by the industry in freshwater and the rise in cancer cases among the population in China. Methods A systematic review was undertaken of the scientific literature compiled in the MEDLINE (via PubMed©), Google scholar, Web of Knowledge. The descriptors used were "cancer", "water pollution”, “industry” and “chemical", limited to studies that relevant to the research questions. Articles selected were of any type in English, from the inception of the indexing of the primary source until July 28th of 2013. With the quantitative data, Health impact assessment formulas are developed and then applied to subsequent data to make estimate. Results The search generated 306 articles, from which 10 were selected after applying the inclusion and exclusion criteria. The analysis of freshwater contaminants that attributed to industry in this review included aromatic amine, vinyl chloride, benzene, hexavalent Chromium, dioxin, and others of industrial origin. The majority of the studies find a significant link between exposure to drinking water contaminants and the increase in cancer cases, especially in the rural areas. In some of the studied populations a significant dose-response relationship was observed. Discussion After reviewing the included studies and the estimation of health impact assessment, I concluded that the association between cancer risks and industrial contamination in freshwater resources in China does indeed exist. While there are several other factors that interact the cancer risks, such as agriculture related water pollution and rapid growth of population. Taking into account that most of the articles were located in western countries, more Chinese studies are required in order to know the effect of freshwater contamination on cancer risks, in particular among those who lived in rural industry area. Conclusion This study provides the first estimated health impacts based on the relationship between industrial freshwater pollution and cancer risks, supporting decision makers to formulate public health recommendations to ensure a safer and healthier environment in the future. However, further study is critically needed for the prevention of this form of contamination.
published_or_final_version
Public Health
Master
Master of Public Health
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10

Kwok, Wing-hin Kevin Patrick. "On the derivation of Water and Sediment Quality Guidelines : some pressing issues and their resolutions /." Click to view the E-thesis via HKUTO Click to view the E-thesis via HKUTO, 2009. http://sunzi.lib.hku.hk/hkuto/record/B2181963.

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11

De, Luca Antonella. "Fenton and Photo-Fenton like at neutral pH for the removal of emerging contaminants in water and wastewater effluents." Doctoral thesis, Universitat de Barcelona, 2016. http://hdl.handle.net/10803/399786.

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In the last decades, the scientific community has been involved in the research of new kinds of contaminants generally known as of “emerging concern” (CECs). The harmfulness of CECs, even at small concentrations as well as, property of bioaccumulation and persistence, makes them extremely dangerous for the human health. The scientific community is constantly researching about novel treatments able to achieve the removal of these contaminants. Advanced Oxidation Processes (AOPs) are considered one of the most useful treatments to achieve CECs degradation. Among the AOPs, Fenton and photo‐Fenton processes are particularly powerful, cheap and easily managed. Nevertheless, some setting requirements of Fenton processes have limited their application at industrial scale. One of the most important limits is the necessity to operate a tight control of the pH in order to avoid iron precipitation (optimum pH~2.8). Unfortunately, the optimum pH for Fenton reaction is essentially far from the normal values of the wastewater treatment plant (WWTP) effluents. Scientific community is then working on the improvement of the operating conditions of Fenton processes in order to improve the applicability in wastewater treatment. These modifications are essentially focused on the possibility to perform the treatment at circumneutral pH (Fenton and photo‐ Fenton like processes). Fenton like processes can be carried out in heterogeneous or homogeneous way according to the phase of the catalyst into the solution. In this study was firstly confirmed the suitability of Fenton based processes in recalcitrant compounds removal. Fenton, UV‐A photo‐Fenton and UV‐C photo‐Fenton were, in fact, applied for atrazine removal from secondary effluent (SE) of municipal wastewater treatment plant (MWWTP). UV‐A and UV‐C photo‐Fenton allowed remove 50% and 100% of the initial atrazine content respectively. The main objective of this thesis was then the assessment of photo‐Fenton’s suitability for recalcitrant contaminant at circumneutral pH. Thus, homogeneous photo‐Fenton like at neutral pH was applied for sulfamethoxazole (SMX) removal. In order to avoid iron precipitation, chelating agents were used to keep soluble the iron at circumneutral pH. The chelating ability of four chelating agents (ethylenediaminetetraacetic acid‐EDTA, nitrilotriacetic acid‐NTA, oxalic acid and tartaric acid) was tested. Then, once determined the optimum molar ratio L:Fe for iron chelation (1.5:1 for EDTA and NTA, 10:1 for tartaric acid and 20:1 for oxalic acid), their catalytic activity was evaluated when employed in photo‐Fenton like for SMX removal. The highest SMX percentage removal, together with the minimum chelating agents required and the better property of biodegradability and low toxicity, demonstrated the suitability of NTA for the purpose. A further study on the stability of the chelates under reaction was carried out. The operating conditions adopted for the treatment significantly influence the stability of the chelate solution. Thus, in order to proper control the parameter set up the behavior of chelates has been study under thermal, oxidative and photochemical stress. It was demonstrated as the temperature control can represent an interesting tool to extend the chelates lifetime under oxidative and photochemical stress. By adopting different H2O2 doses, a linear correlation between doses and chelate decomposition could be identified. The better suitability of UV‐A irradiation, against UV‐C and Xe lamp, to preserve the iron chelate solution was demonstrated. Moreover, the influence of the influent characteristics on the process efficiency needed to be also considered. Thus, different water matrices were used for the experiments. The efficiency of photo‐Fenton like catalyzed by Fe(III)‐NTA has been compared when applied to different aqueous matrixes (Milli‐Q water, tap water, secondary effluent wastewater and well water). It was demonstrated as the ions content, especially Ca2+ and Mg2+, significantly compromise the process of chelation. High alkalinities and organic matter, instead, mainly influenced the phase of process, when acting as radicals scavengers, reduced the amount available for SMX oxidation. Some strategies were then adopted to promote SMX removal. Between them, Mn2+ mediated photo‐Fenton like showed somehow possibility for improvement. Highest removal rate was in fact exhibited in the first minutes of reaction when adding Mn2+ to the solution in ratio molar Mn:Fe 0.5:1. The conclusive study of the thesis regarded the assessment of the Br‐ presence on the efficiency achievable in recalcitrant compounds removal when applying UV/PS/Fe2+ for removal of benzophenone‐4 (BZ4), nitrobenzene (NB), nitrobenzoic acid (NBA), atrazine (ATZ) and ampicilline (AMP). Br‐ demostrated to be a strong inhibitor in the removal of all the considered contaminants except for NB when, the removal was instead enhanced in bromide containing water.
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Sang, Ziye. "Probing the environmental fate of emerging contaminants and their ecological impacts on aquatic environment." HKBU Institutional Repository, 2016. https://repository.hkbu.edu.hk/etd_oa/295.

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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.
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Rojas, Cardozo Mario Roberto. "ADVANCED OXIDATION OF CHEMICALS OF EMERGING CONCERN: MODELING AND EXPERIMENTAL SIMULATION." Diss., The University of Arizona, 2011. http://hdl.handle.net/10150/202534.

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Every year, new trace chemicals are detected in natural waters as well as treated wastewater effluents all over the world. Public health and environmental concerns have driven the development of new technologies to treat water and eliminate chemicals that may pose risk to humans and wildlife. This work presents a detailed statistical analysis on the removal of some of the most widely occurring chemicals of emerging concern in wastewater based on information available in the literature. Results show that existing water treatment processes only partially eliminate most of these contaminants. Advanced oxidation processes (AOPs) are some of the technologies that have shown the most promising results for the removal of recalcitrant organics in water. Hydrogen peroxide photolysis (UV/H₂O₂) and Fenton’s reaction are some examples of AOPs that use hydroxyl radicals to oxidize organics. The kinetics of UV/H₂O₂ and Fenton’s reaction were studied from the experimental and mathematical points of view. Comprehensive models with no adjustable parameters successfully accounted for radical initiation via photolysis of H₂O₂ or radical initiation via Fenton’s mechanism; reaction of organic targets such as p-cresol and nonylphenol with hydroxyl radicals; and recombination mechanisms, as well as changes in solution pH due to evolution of carbon dioxide because of target mineralization. The presence of radical scavengers was successfully handled by the models, suggesting that they can be generalized to the treatment of complex matrices. The UV/H₂O₂ model was also extended to solar catalyzed applications. Using an atmospheric solar irradiation model (SMART) and data from the Giovanni-NASA online database, ground-level solar spectral irradiance were obtained and used as model inputs. The kinetic model provided an excellent fit to experimental results obtained with p-cresol and fluorescein targets using no fitted parameters. The UV/H₂O₂ process was also studied in commercial flow-through UV reactors with monochromatic and polychromatic light sources. Organic targets of interest such as pcresol can be degraded effectively in these reactors at relatively low peroxide concentrations. Results with wastewater effluents suggest that these commercial reactors can be used for AOP tertiary treatment as a way to reduce dissolved organic matter and eliminate potential harmful chemicals present in the water.
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Yamal, Turbay Evelyn. "Efficient operation of photo-Fenton process for the treatment of emerging contaminants in water solutions." Doctoral thesis, Universitat Politècnica de Catalunya, 2013. http://hdl.handle.net/10803/134805.

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The growth of population density in some areas of the planet and the increasing fast advances in technology and energy issues, have resulted in a remarkable increment in the necessity for goods and services, with a subsequent over-exploitation and pollution of the environmental resources. Water, a non-renewable resource, does not escape from the harmful effects of human activity and its increasing pollution levels threaten the normal development of ecosystems and life as well. In the last decades, the occurrence of a new generation of contaminants has been detected in wastewaters, surface and underground waters, and even in drinking water. These substances, called "emerging contaminants" or "emerging pollutants", are not subject to regulation, but their recalcitrant character and their effects as endocrine disruptors suggest that their bio-accumulation will have severe consequences to the environment. These non-biodegradable compunds cannot be removed in conventional wastewater treatment plants, and there is a need for chemical processes to oxidize them at least to bio-degradable or non-toxic species. Advanced oxidation processes (AOPs) have demonstrated to be particularly useful in degrading and eventually mineralizing emerging contaminants, but the complexity of their mechanisms and the high reagent and energy costs involved, make necessary to develop options to improve their performance. This thesis specifically addresses the photo-Fenton process, an advanced oxidation process which has been widely applied and has demonstrated to be efficient in the degradation of recalcitrant organic contaminants. The objective of this thesis is to investigate and to propose operating alternatives to improve the performance of photo-Fenton process. For that aim, it was necessary to fulfill some specific objectives: to perform a detailed study of the variables involved in the process, propose its enhancement throughout a systematic dosage of hydrogen peroxide along the treatment span, simulate the process and to investigate opportunities to optimize the process batch recipe. In the first stage of the investigation, with a clear experimental approach, the variables involved in the process were studied and a novel, flexible and easy-to-implement hydrogen peroxide systematic dosage protocol was proposed, improving the mineralization of three emerging contaminants, reaching almost total mineralization in some of the cases. However, the effectiveness of the protocol is strongly influenced by the crossed effect between the involved parameters. In a subsequent stage, a computational approach, the process involving the proposed dosage protocol is simulated and the performance of the process was predicted at different operational conditions. The opportunities for improving process performance when the parameters concerning the dosage protocol are conveniently adjusted can be addressed. Finally, taking a step forward, a first attempt to investigate the alternatives for process optimization was investigated, demonstrating that operational costs can be reduced without diminishing the quality of the final product. As a final remark, this thesis supposes a step forward in the improvement of advanced oxidation processes and it opens the door to continue developing strategies to model, simulate and optimize these complex processes.
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Raimundo, Cassiana Carolina Montagner 1981. "Contaminantes emergentes em água tratada e seus mananciais = sazonalidade, remoção e atividade estrogênica." [s.n.], 2011. http://repositorio.unicamp.br/jspui/handle/REPOSIP/249643.

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Orientador: Wilson de Figueiredo Jardim
Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Química
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Resumo: O objetivo deste trabalho foi avaliar, através de um perfil anual, a qualidade dos mananciais e da água tratada de Campinas (SP) em relação à presença de cafeína, estrona, 17b-estradiol, estriol, progesterona, testosterona, 17a-etinilestradiol, mestranol, levonorgestrel, dietilestilbestrol, triclosan, 4-n-octilfenol, 4-n-nonilfenol, bisfenol A, fenolftaleína e atrazina empregando extração em fase sólida (SPE) e cromatografia líquida acoplada ao espectrômetro de massas (LC-MS/MS), e verificar o potencial estrogênico das amostras usando o bioensaio Bioluminesce Yeast Estrogen Screening (BLYES). Os resultados mostraram a presença de seis dos 16 compostos investigados em pelo menos uma amostra de água tratada. A estrona foi detectada apenas uma vez. Concentrações de atrazina de até 687 ng L foram determinadas nas amostras provenientes do rio Capivari, e nas amostras de água tratada provenientes do rio Atibaia as concentrações não passaram de 42 ng L. A fenolftaleína foi determinada em apenas uma campanha em todas as amostras provenientes do rio Atibaia em concentrações de até 20 ng L. As concentrações médias de bisfenol A e triclosan foram 7 e 17 ng L, respectivamente. Nos mananciais foram determinados 13 dos 16 compostos investigados. Todas as amostras de água bruta e tratada apresentaram concentrações de cafeína que variaram significativamente entre os períodos de seca e cheia dos rios. As estações de tratamento de água de Campinas, operando no sistema convencional foram capazes de remover entre 30 e 99% dos contaminantes investigados. No mais, 40 % das amostras de água tratada apresentaram atividade estrogênica positiva (entre 0,01 e 1,33 ngE2equiv L) e todas as amostras de água bruta apresentaram estrogenicidade entre 0,06 e 6,54 ngE2equiv L. Sendo que estas foram maiores nos períodos de estiagem
Abstract: The purpose of this work was to evaluate an annual profile of both source of supply and drinking water quality in the city of Campinas (São Paulo State) in relation to the presence of caffeine, estrone, 17b-estradiol, estriol, progesterone, testosterone, 17a-ethynylestradiol, mestranol, levonorgestrel, diethylstilbestrol, triclosan, 4-n-octylphenol, 4-n-nonylphenol, bisphenol A, phenolphthalein and atrazine using Solid Phase Extraction (SPE) and Liquid Chromatography with Tandem Mass Spectrometry Detection (LC-MS/MS), and make sure the estrogenic potential of samples using Bioluminesce Yeast Estrogen Screening bioassay (BLYES). Results showed the presence of six of the 16 compounds investigated in least one sample of drinking water (estrone, triclosan, bisphenol A, phenolphthalein, atrazine and caffeine). Atrazine concentrations up to 687 ng L were found in drinking water samples from the Capivari River. In drinking water samples from the Atibaia River, the concentrations did not exceed 42 ng L. Phenolphthalein was determined in only one campaign in both raw and treated water from the Atibaia River at concentrations around 20 ng L. Average concentrations of bisphenol A and triclosan in drinking water samples were 7 and 17 ng L, respectively. Thirteen of the 16 investigated compounds were determined in surface waters. All samples of raw and treated water showed concentrations of caffeine that varied significantly between dry and wet seasons. The conventional water treatment plants in Campinas were able to remove between 30 and 99 % of the investigated contaminants. The estrogenic activity was evaluated using BLYES bioassay, where 40% of drinking water samples showed positive estrogenic activity (between 0.01 and 1.33 ngE2equiv L) and all samples of surface water presented estrogenic activity between 0.06 and 6.54 ngE2equiv L. These values were higher in dry winter periods
Doutorado
Quimica Analitica
Doutor em Ciências
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16

Saccà, Maria Ludovica <1982&gt. "Emerging contaminants in agricultural ecosystems: impact of selected pharmaceutical on water and soil ecology and pratical implications." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2010. http://amsdottorato.unibo.it/3083/.

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Pharmaceuticals are useful tools to prevent and treat human and animal diseases. Following administration, a significant fraction of pharmaceuticals is excreted unaltered into faeces and urine and may enter the aquatic ecosystem and agricultural soil through irrigation with recycled water, constituting a significant source of emerging contaminants into the environment. Understanding major factors influencing their environmental fate is consequently needed to value the risk, reduce contamination, and set up bioremediation technologies. The antiviral drug Tamiflu (oseltamivir carboxylate, OC) has received recent attention due to the potential use as a first line defence against H5N1 and H1N1 influenza viruses. Research has shown that OC is not removed during conventional wastewater treatments, thus having the potential to enter surface water bodies. A series of laboratory experiments investigated the fate and the removal of OC in surface water systems in Italy and Japan and in a municipal wastewater treatment plant. A preliminary laboratory study investigated the persistence of the active antiviral drug in water samples from an irrigation canal in northern Italy (Canale Emiliano Romagnolo). After an initial rapid decrease, OC concentration slowly decreased during the remaining incubation period. Approximately 65% of the initial OC amount remained in water at the end of the 36-day incubation period. A negligible amount of OC was lost both from sterilized water and from sterilized water/sediment samples, suggesting a significant role of microbial degradation. Stimulating microbial processes by the addition of sediments resulted in reduced OC persistence. Presence of OC (1.5 μg mL-1) did not significantly affect the metabolic potential of the water microbial population, that was estimated by glyphosate and metolachlor mineralization. In contrast, OC caused an initial transient decrease in the size of the indigenous microbial population of water samples. A second laboratory study focused on basic processes governing the environmental fate of OC in surface water from two contrasting aquatic ecosystems of northern Italy, the River Po and the Venice Lagoon. Results of this study confirmed the potential of OC to persist in surface water. However, the addition of 5% of sediments resulted in rapid OC degradation. The estimated half-life of OC in water/sediment of the River Po was 15 days. After three weeks of incubation at 20 °C, more than 8% of 14C-OC evolved as 14CO2 from water/sediment samples of the River Po and Venice Lagoon. OC was moderately retained onto coarse sediments from the two sites. In water/sediment samples of the River Po and Venice Lagoon treated with 14C-OC, more than 30% of the 14C-residues remained water-extractable after three weeks of incubation. The low affinity of OC to sediments suggests that the presence of sediments would not reduce its bioavailability to microbial degradation. Another series of laboratory experiments investigated the fate and the removal of OC in two surface water ecosystems of Japan and in the municipal wastewater treatment plant of the city of Bologna, in Northern Italy. The persistence of OC in surface water ranged from non-detectable degradation to a half-life of 53 days. After 40 days, less than 3% of radiolabeled OC evolved as 14CO2. The presence of sediments (5%) led to a significant increase of OC degradation and of mineralization rates. A more intense mineralization was observed in samples of the wastewater treatment plant when applying a long incubation period (40 days). More precisely, 76% and 37% of the initial radioactivity applied as 14C-OC was recovered as 14CO2 from samples of the biological tank and effluent water, respectively. Two bacterial strains growing on OC as sole carbon source were isolated and used for its removal from synthetic medium and environmental samples, including surface water and wastewater. Inoculation of water and wastewater samples with the two OC-degrading strains showed that mineralization of OC was significantly higher in both inoculated water and wastewater, than in uninoculated controls. Denaturing gradient gel electrophoresis and quantitative PCR analysis showed that OC would not affect the microbial population of surface water and wastewater. The capacity of the ligninolytic fungus Phanerochaete chrysosporium to degrade a wide variety of environmentally persistent xenobiotics has been largely reported in literature. In a series of laboratory experiments, the efficiency of a formulation using P. chrysosporium was evaluated for the removal of selected pharmaceuticals from wastewater samples. Addition of the fungus to samples of the wastewater treatment plant of Bologna significantly increased (P < 0.05) the removal of OC and three antibiotics, erythromycin, sulfamethoxazole, and ciprofloxacin. Similar effects were also observed in effluent water. OC was the most persistent of the four pharmaceuticals. After 30 days of incubation, approximately two times more OC was removed in bioremediated samples than in controls. The highest removal efficiency of the formulation was observed with the antibiotic ciprofloxacin. The studies included environmental aspects of soil contamination with two emerging veterinary contaminants, such as doramectin and oxibendazole, wich are common parasitic treatments in cattle farms.
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Al, Anazi Abdulaziz H. "Synthesis of Recyclable Magnetic Metal-ferrite Nanoparticles for the Removal of Contaminants of Emerging Concern in Water." University of Cincinnati / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1543922143864275.

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18

Edziyie, Regina E. "Characterization of Triclocarban, Methyl- Triclosan, and Triclosan in Water, Sediment, and Corbicula Fluminea (Müller, 1774) Using Laboratory, in Situ, and Field Assessments." Thesis, University of North Texas, 2011. https://digital.library.unt.edu/ark:/67531/metadc67978/.

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In the last decade emerging contaminants research has intensified in a bid to answer questions about fate, transport, and effects as these chemicals as they get released into the environment. The chemicals of interest were the antimicrobials; triclocarban (TCC) and triclosan (TCS), and a metabolite of triclosan, methyl triclosan (MTCS). This research was designed to answer the question: what is the fate of these chemicals once they are released from the waste water treatment plant into receiving streams. Three different assessment methods; field monitoring, in-situ experiments, and laboratory studies were used to answer the overall question. TCS, TCC, and MTCS levels were measured in surface water, sediment and the Asiatic clam Corbicula fluminea. Field studies were conducted using four sites at Pecan Creek, Denton TX. Levels of all three chemicals in clams were up to fives orders of magnitude the water concentrations but an order of magnitude lower than in sediment. Highest sediment levels of chemicals were measured in samples from the mouth of Pecan Creek (highest organic matter). TCC was the most and TCS was the least accumulated chemicals. In-situ and lab studies both indicated that uptake of these chemicals into the clams was very rapid and measurable within 24hours of exposure. The after clams were transferred into clean water most of the compounds were depurated within 14 days.
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Jones, Steven Michael. "Nanofiltration Rejection of Contaminants of Emerging Concern from Municipal Water Resource Recovery Facility Secondary Effluents for Potable Reuse Applications." Thesis, University of Arkansas, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10107894.

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As reuse of municipal water resource recovery facility (WRRF) effluent becomes vital to augment diminishing fresh drinking water resources, concern exists that conventional barriers may prove deficient and the upcycling of contaminants of emerging concern (CECs) could prove harmful to human health and aquatic species if more effective and robust treatment barriers are not in place.

There are no federal Safe Drinking Water Act (SDWA) regulations in place specifically for direct potable reuse (DPR) of WRRF effluent. Out of necessity, some states are developing their own DPR reuse regulations. Currently, reverse osmosis (RO) is the default full advanced treatment (FAT) barrier for CEC control. However, the potential exists for tight thin-film composite (TFC) nanofiltration (NF) membranes to provide acceptable CEC rejection efficacies for less capital, operations and maintenance (O&M), energy, and waste generated.

Recognizing the inherent complexity of CEC rejection by membranes, this research program was designed to elucidate the vital predictive variables influencing the rejection of 96 CECs found in municipal WRRF effluents. Each of the CECs was cataloged by their intended use and quantitative structure activity relationship (QSAR) properties, and measured in secondary effluent samples from WRRFs in Texas and Oklahoma. These secondary effluent samples were then processed in bench-scale, stirred, dead-end pressure cells with water treatment industry-specified TFC NF and RO membranes.

A multi-level, multi-variable model was developed to predict the probable rejection coefficients of CECs with the studied NF membrane. The model was developed from variables selected for their association with known membrane rejection mechanisms, CEC-specific QSAR properties, and characteristics of the actual solute matrix. R statistics software version 3.1.3 was utilized for property collinearity analysis, outlier analysis, and regression modeling. The Pearson correlation method was utilized for selection of the most vital predictor variables for modeling. The resulting Quantitative Molecular Properties Model (QMPM) predicted the NF rejection CECs based on size, ionic charge, and hydrophobicity. Furthermore, the QMPM was verified against a CEC rejection dataset published by an independent study for a similar commercially available TFC NF membrane.

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Valls, Cantenys Carme. "Development of analytical methodologies for the determination of emerging contaminants and phosphorus compounds." Doctoral thesis, Universitat de Girona, 2014. http://hdl.handle.net/10803/284742.

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The presence of anthropogenic chemical substances in water resources can affect the ecological balance of aquatic systems, as well as human health, and therefore it is necessary to control their presence in water bodies. The objective of this thesis is the development of analytical methodologies for the determination of phosphorus species and organic micropollutants in water samples. Firstly, two speciation methods for the determination of simple and condensate phosphorus oxoanions have been developed, using HPLC separation coupled to ICP-AES in one methodology and to ICP-MS in the other. Two analytical methodologies have been developed for the determination of endocrine disrupting compounds using PDMS rod extraction. The determination was carried out by GC-MS for flame retardants and by HPLC-DAD for phenolic compounds. Finally, a multiresidue method based on SPE followed by LC-MS/MS have been developed for the determination of 35 analytes, including pharmaceuticals, corrosion inhibitors, and pesticides, in water samples
La contaminació de l’aigua per compostos d’origen antropogènic pot afectar tant al medi ambient com a la salut humana i per tant és necessari controlar-ne la presència. L’objectiu de la tesi és desenvolupar metodologies analítiques per a determinació de espècies de fòsfor i microcontaminants orgànics en mostres d’aigua. En primer lloc, s’han desenvolupat dos mètodes d’especiació per a la determinació de oxoanions de fòsfor simples i condensats, mitjançant separació per HPLC acoblada a ICP-AES en un mètode, i a ICP-MS en l’altre. També s’han desenvolupat dos mètodes utilitzant extracció amb cordó de PDMS per a la determinació de compostos que actuen com a disruptors endocrins. La determinació es va portar a terme per GC-MS per als retardants de flama bromats i per HPLC-DAD per als compostos fenòlics. Finalment es va desenvolupar un mètode multiresidu basat en SPE seguit de LC-MS/MS per a la determinació de 35 analits, incloent compostos farmacèutics, inhibidors de la corrosió i plaguicides
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Adeleye, Adeola Patience. "Perfluorinated compounds, bishenol a and acetaminophen in selected waste water treatment plants in and around Cape Town, South Africa." Thesis, Cape Peninsula University of Technology, 2016. http://hdl.handle.net/20.500.11838/2331.

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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).
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Solano, Marize de Lourdes Marzo [UNESP]. "Abordagem metodológica para a valuação do petencial desregulador endócrino de água de beber: estudo com amostras reais." Universidade Estadual Paulista (UNESP), 2014. http://hdl.handle.net/11449/123331.

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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
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Solano, Marize de Lourdes Marzo. "Abordagem metodológica para avaliação do potencial desregulador endócrino de água de beber : estudo com amostras reais /." Botucatu, 2014. http://hdl.handle.net/11449/123331.

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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
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24

White, Madeleine Michael Isabella. "Optimization and Longevity of Functionalized Multi-Walled Carbon Nanotube-Enabled Membranes for Water Treatment." DigitalCommons@CalPoly, 2020. https://digitalcommons.calpoly.edu/theses/2174.

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Water scarcity is a growing concern at the global scale. Large scale water reuse is growing both in necessity and popularity. Before water reuse can be performed efficiently on a large scale or be used for potable supply, even indirectly, contaminants of emerging concern (CECs) will need to be treated at the full scale. Advanced oxidation processes (AOPs) are a form of advanced water treatment capable of treating a wide range of CECs. This study contributes to the growing field of AOPs and more specifically AOPs using ozone combined with functionalized multi-walled carbon nanotubes (MWCNTs). Ozonation of MWCNTs has been found to increase hydroxyl radical production and improve AOP treatment. Novel MWCNT-enabled membranes were used as catalysts for ozonation to degrade the CEC Atrazine. Atrazine is an ozone recalcitrant CEC that is commonly found in herbicides. Atrazine removal results, found using a high-performance liquid chromatograph (HPLC), were inconsistent between membranes constructed using identical procedures. Further analysis using Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopes (SEM), and UV-Vis spectrophotometry was conducted to explore inconsistencies in construction of the membranes which might explain removal inconsistencies and predict membrane longevity. Removal was found to be influenced by filtration time and ozone exposure. Ozone exposure and filtration time influence percent removal because they both affect hydroxyl formation. The membrane test filtration duration, for equal filtered volumes, ranged from under 5 minutes to nearly an hour. It is believed that filtration time inconsistency was due to inconsistent MWCNT loading on the surface of the membranes. Extended exposure to ozone might change the surface chemistry of the MWCNTs on the membrane surface, affecting hydroxyl radical production. Additionally, repeated use of the membrane created surface defects that might reduce the membrane strength. This study found that the lifetime of the membrane is far past what was simulated in lab and further testing must be performed.
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Abdelraheem, Wael H. M. "Catalytic and Photocatalytic Removal of Contaminants of Emerging Concerns (CECs) and Per-/Polyfluoroalkyl Substances (PFAS) from Wastewater Effluents for Water Reuse Applications." University of Cincinnati / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1613751353837349.

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26

Garner, Emily Dawn. "Occurrence and Control of Microbial Contaminants of Emerging Concern through the Urban Water Cycle: Molecular Profiling of Opportunistic Pathogens and Antibiotic Resistance." Diss., Virginia Tech, 2018. http://hdl.handle.net/10919/93743.

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In an era of pervasive water stress caused by population growth, urbanization, drought, and climate change, limiting the dissemination of microbial contaminants of emerging concern (MCECs) is of the utmost importance for the protection of public health. In this dissertation, two important subsets of MCECs, opportunistic pathogens (OP) and antibiotic resistant genes (ARG), are studied across several compartments of the urban water cycle, including surface water, stormwater, wastewater, recycled water, and potable water. Collectively, this dissertation advances knowledge about the occurrence of OPs and ARGs across these water systems and highlights trends that may be of value in developing management strategies for limiting their regrowth and transmission. Field studies of two surface water catchments impacted by stormwater runoff demonstrated the prevalence of ARGs in urban stormwater compared to pristine, unimpacted sites, or to days when no precipitation was recorded. The role of wastewater reuse in transmitting OPs and ARGs was also investigated. Traditional tertiary wastewater treatment plants producing water for non-potable use were found to be largely ineffective at removing ARGs, but plants using advanced oxidation processes or ozonation paired with biofiltration to produce direct potable reuse water were highly effective at removing ARGs. Non-potable reclaimed water consistently had greater quantities of sul1, a sulfonamide ARG, and Legionella and Mycobacterium, two OPs of significant public health concern, present than corresponding potable systems. Limited regrowth of OPs and ARGs did occur in simulated premise (i.e., building) plumbing systems operated with direct potable reuse waters, but regrowth was comparable to that observed in systems fed with potable water derived from surface or groundwater. Advancements were also made in understanding the role of several hypothesized driving forces shaping the antibiotic resistome in natural and engineered water systems: selection by antimicrobials and other compounds, horizontal gene transfer, and microbial community composition. Finally, whole-genome and metagenomic characterization were applied together towards profiling L. pneumophila in clinical and water samples collected from Flint, Michigan, where an economically-motivated switch to an alternative water source created conditions favorable for growth of this organism and likely triggered one of the largest Legionnaires' Disease outbreaks in U.S. history.
PHD
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Rowsell, Victoria Francesca. "Estimating the removal of micropollutants and emerging contaminants from sewage treatment processes in preparation for the implementation of the Water Framework Directive." Thesis, Imperial College London, 2009. http://hdl.handle.net/10044/1/5567.

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Public awareness on the impacts that micropollutants and emerging contaminants have on aquatic resources has increased in recent decades and has become a significant driver for reducing levels of contaminants in the environment. The most recent and comprehensive initiative of the European Union in the area of water protection is the Water Framework Directive (WFD), which entails the application of new technical standards for surface water quality. It has been reported that sewage treatment works (STWs) are a major source of micropollutants for receiving aquatic environments. As a result of this, STWs are increasingly becoming a target for regulatory and public pressure with regard to their discharges to the environment. The micropollutants and emerging contaminants considered in this thesis have been identified under the European Union as substances that are toxic, persistent, and likely to bioaccumulate. This thesis aimed to develop a model to estimate concentrations and loads of micropollutants and emerging contaminants at site specific STWs to aid the implementation of the WFD by 2015. The thesis also focused on a case study to evaluate the need for tertiary treatment to remove micropollutants and emerging contaminants using a detailed laboratory analysis to assess the removal ability of a selected tertiary treatment. The results of the model designed in this research were used as part of a risk assessment which focused on understanding the risk that site specific STWs posed to the environment, and on their removal efficiencies. The risk assessment enables the most at risk STWs to be prioritised for investment and will facilitate management options in seeking to satisfy the WFD. The thesis, through extensive research, also aimed to detail knowledge gaps present in the UK water industry regarding sources, pathways, fate, and behaviour of micropollutants and emerging contaminants. Finally, recommendations were outlined regarding future steps to help meet the requirements of the WFD.
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Herrero, Gil Pol. "Analytical methods for the determination and evaluation of emerging organic contaminants in environmental waters and sludge." Doctoral thesis, Universitat Rovira i Virgili, 2014. http://hdl.handle.net/10803/320184.

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Aquesta tesi doctoral se centra en el desenvolupament de mètodes analítics per determinar famílies poc estudiades de contaminants orgànics emergents en aigües ambientals i mostres de llots de depuradora. Els compostos inclosos en aquesta Tesi són els glucocorticoides, els ionòfors de polièter, les benzotriazoles, les benzotiazoles, les benzenosulfonamides i els ful·lerens. En aquesta Tesi, es demostren les capacitats ofertes per les tècniques de determinació d'avantguarda, tals com la "ultra-high performance liquid chromatography (UHPLC)" i la "Asymmetrical flow field-flow Fractionation (AF4 )" acoblades a analitzadors de masses de tipus triple quadrupol (QqQ) o Orbitrap per a l’anàlisi de mostres ambientals. A més, l'ús de tècniques d'extracció emergents en el camp mediambiental, com ara "pressurised hot water extraction (PHWE)" i QuEChERS, es van explorar per a l'anàlisi de mostres de llots de depuradora. Aquestes tècniques poden ser avantatjoses en comparació amb altres tècniques d'extracció emprades en l'actualitat en l'anàlisi mediambiental, també utilitzades en aquesta Tesi, com ara la "pressurised liquid extraction ( PLE)". També en aquesta Tesi, es proporciona informació de la presència d'aquests contaminants orgànics emergents en l'aigua de riu, les aigües residuals i mostres de llots de depuradores de diferents rius i EDARs de Catalunya. A més, s'informa de les dades sobre l'eliminació d'aquests compostos tant pels tractaments d'aigües residuals secundaris i terciaris i, alguns d’ells s’han determinat per primera vegada.
Esta Tesis Doctoral se centra en el desarrollo de métodos analíticos para determinar familias poco estudiadas de contaminantes orgánicos emergentes en aguas ambientales y muestras de lodos de depuradora. Los compuestos incluidos en esta Tesis son los glucocorticoides, los ionóforos de poliéter, las benzotriazolas, las benzotiazolas, las bencenosulfonamidas y los fulerenos. En esta Tesis, se demuestran las capacidades ofrecidas por las técnicas de determinación de vanguardia, tales como la “ultra-high performance liquid chromatography (UHPLC)” y la “asymmetrical flow field-flow fractionation (AF4)” acopladas a analizadores de masas de tipo triple cuadrupolo (QqQ) o Orbitrap para el análisis de muestras ambientales. Además, el uso de técnicas de extracción emergentes en el campo medioambiental, tales como “pressurised hot water extraction (PHWE)” y QuEChERS, se exploraron para el análisis de muestras de lodo de depuradora. Estas técnicas pueden ser ventajosas en comparación con otras técnicas de extracción empleadas en la actualidad en el análisis medioambiental, también utilizadas en esta Tesis, tales como “pressurised liquid extraction (PLE)”. También en esta Tesis, se proporciona información de la presencia de estos contaminantes orgánicos emergentes en el agua de río, las aguas residuales y muestras de lodos de depuradoras de diferentes ríos y EDARs de Cataluña. Además, se informa de los datos sobre la eliminación de estos compuestos tanto por los tratamientos de aguas residuales secundarias y terciarias y, algunos de ellos han sido determinados por primera vez.
This Doctoral Thesis focuses on the development of analytical methods to determine little studied families of emerging organic contaminants in environmental waters and sewage sludge samples. The compounds included in this Thesis are glucocorticoids, polyether ionophores, benzotriazoles, benzothiazoles, benzenesulfonamides and fullerenes. In this Thesis, the capabilities offered by cutting-edge determination techniques such as ultra-high performance liquid chromatography (UHPLC) or asymmetrical flow field-flow fractionation (AF4) coupled to triple quadrupole (QqQ) or Orbitrap-based mass spectrometry analysers are demonstrated. In addition, the use of emerging extraction techniques in the field of environmental analysis, such as pressurised hot water extraction (PHWE) and QuEChERS, were explored for the analysis of sewage sludge samples. These techniques can be advantageous as compared to other extraction techniques currently employed in environmental analysis and also used in this Thesis such as pressurised liquid extraction (PLE). Also in this Thesis, information of the occurrence of these emerging organic contaminants in river water, sewage and sewage sludge samples from different rivers and STPs from Catalonia is provided. Additionally, data about the removal of these compounds both by secondary and tertiary sewage treatments is reported and some of them were determined for the first time.
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Blanco, Ortiz Albert. "Detección y caracterización de virus emergentes en su ciclo ambiental." Doctoral thesis, Universitat de Barcelona, 2021. http://hdl.handle.net/10803/673934.

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Besides classic enteric viruses such hepatitis A virus and norovirus, there are other viruses that can reach water sources without being part of their transmission route. Some of these pathogens are enveloped viruses, which complicates their recovery with the usual concentration methods for the classic naked enteric viruses. Glass wool filtration followed by polyethylene glycol (PEG) 6000 precipitation is cheap and reliable for recovering non-enveloped viruses, but is inefficient for the concentration of enveloped viruses. Thus, the first goal of this Thesis was the optimization of the glass wool filtration method for the recovery of enveloped viruses without losing efficiency for the recovery of naked viruses. Once optimized, this protocol was used to concentrate viruses from multiple water types such drinking water, surface water, well water, wastewater and brackish pond water. The results presented suggest that the optimized glass wool filtration method is useful and reliable for recovering both enveloped and non-enveloped viruses. Of particular interest was the characterization of a norovirus outbreak of gastroenteritis associated to the consumption of bottled water. Remarkably, several emerging viruses, such as non- classical astroviruses, West Nile virus and rat coronaviruses, were detected in samples from Riyadh (Saudi Arabia), and Barcelona. Additionally, a monthly surveillance of enterovirus in the Barcelona wastewater was implemented for the control of the circulation of highly pathogenic species such as Enterovirus A71 and D68. The dominant consensus sequence and the ensemble of major and minor sequences were determined by Sanger and deep sequencing, respectively.
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Pais, Goyache Irene. "DEVELOPMENT OF A CHEMICAL FINGERPRINT FOR DETECTING UNTREATED HUMAN SEWAGE POLLUTION IN SURFACE WATER." Master's thesis, Temple University Libraries, 2015. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/360924.

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Civil Engineering
M.S.Env.E.
Untreated human sewage pollution in surface water is of concern because it contributes to the degradation of aquatic ecosystems and it could be a potential hazard to human health. Also, any pollution of surface water, which ultimately supplies drinking water, may affect the drinking water quality. Improper operation and maintenance of separate storm sewer systems are prominent contributors of untreated sewage to source waters, resulting from illicit connections, leakage of sewers, or cross-connections. This thesis studied anthropogenic markers to track untreated sewage in an urban watershed with separate storm sewer system, under dry weather conditions. The main feature of these chemical markers is their degradation behavior at municipal wastewater treatment plants: some markers are completely removed (labile markers), whereas others show only partial or no removal at all (conservative markers). A set of ubiquitous chemical markers with practical analytical detection limits was selected to exploit the labile vs conservative distinction, and determine if untreated human sewage was discharged from stormwater outfalls. The presence of labile markers alone was not enough to confirm the occurrence of untreated sewage in stormwater outfalls. The concentration ratios between labile and conservative markers from several chemical groups (pharmaceuticals and personal care products, over-the-counter medications, artificial sweeteners, and human metabolites) created a chemical fingerprint of untreated sewage, and it was statistically demonstrated to track untreated human sewage in local stormwater outfalls.
Temple University--Theses
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31

Gilart, Alzuria Núria. "Preparation and application of novel selective and polar materials for sorptive extraction of emerging contaminants from environmental waters." Doctoral thesis, Universitat Rovira i Virgili, 2014. http://hdl.handle.net/10803/275958.

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The aim of this Doctoral Thesis is the development of novel polymeric materials for different sorptive extraction techniques, such as solid-phase extraction (SPE) and stir bar sorptive extraction (SBSE). Both techniques were applied in liquid-chromatography and tandem mass spectrometry (LC-MS/MS) for determining a group of emerging contaminants, such as pharmaceuticals, illicit drugs and personal care products, from wastewater samples. To improve the detection of these contaminants in several environmental samples at low levels of concentrations, extraction techniques have to enable a high enrichment factor and high selectivity towards the analytes of interest removing interfering compounds. In this Doctoral thesis, a molecularly imprinted polymer (MIP) specific for a group of non-steroidal and anti-inflammatory drugs (NSAIDs) and other polymeric material with strong cation-exchange behaviour were evaluated as sorbents for SPE. Moreover, different monolithic materials with a polar nature were also synthesised to be used as coatings for SBSE and as a result, favour the extraction of more polar compounds
La present Tesi Doctoral té com a objectiu principal el desenvolupament de nous materials per a diferents tècniques d’extracció per sorció, com són l’extracció en fase sòlida i l’extracció mitjançant barres magnètiques agitadores. Ambdues tècniques van ser aplicades a la cromatografia de líquids seguida de l’espectroscòpia de masses en tàndem (LC-MS/MS) per a la determinació de diversos contaminants orgànics considerats com emergents, com són fàrmacs, drogues d’abús i productes d’higiene personal. Per tal de millorar la detecció d’aquests compostos en diferents mostres mediambientals a baixes concentracions, les tècniques d’extracció han de permetre un gran factor de preconcentració, selectivitat cap als analits d’interès i a la vegada eliminar interferències. En aquesta tesi, un polímer comercial d’empremta molecular específic per a un grup de fàrmacs (non-steroidal and antiinflammatory drugs (NSAIDs)) i un altre polímer d’intercanvi catiònic fort sintetitzat al laboratori van ser avaluats com a sorbents per a l’extracció en fase sòlida. A més a més, diferents materials monolítics de caràcter polar van ser també sintetitzats per recobrir barres magnètiques agitadores i així afavorir l’extracció de compostos de polaritat mitjana i elevada.
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Aceña, i. Sánchez Jaume. "Transformació i metabolisme de fàrmacs al medi aquàtic mitjançant l’espectrometria de masses d'alta resolució." Doctoral thesis, Universitat de Barcelona, 2017. http://hdl.handle.net/10803/462804.

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En la societat actual, els fàrmacs són imprescindibles per a millorar la qualitat de vida de les persones però la seva activitat biològica inherent a la seva naturalesa genera una creixent preocupació pels possibles efectes als ecosistemes. Els fàrmacs poden arribar al medi aquàtic i produir una exposició crònica d'organismes, els quals poden resultar afectats. Molts estudis conclouen que per una avaluació més completa és necessari tenir en compte les possibles transformacions que pateixen aquests compostos al medi ambient ja que els productes resultants poden retenir l’activitat biològica del pare o tenir efectes toxicològics superiors al compost original. En el desenvolupament d’aquests tesi s’han estudiat les principals transformacions dels fàrmacs al medi aquàtic, incloent processos biòtics i abiòtics. Aquests estudis s’han realitzat mitjançant metodologies basades en la cromatografia de líquids acoblada a l’espectrometria de masses d’alta resolució (LC-HRMS). Actualment, els espectròmetres de nova generació, han superat les limitacions tradicionals d’aquesta tècnica per a l’anàlisi quantitatiu, oferint linealitats i sensibilitats similars als instruments de triple quadrupol. Evidentment, les prestacions que ens ofereix aquesta tècnica per a l’elucidació estructural de compostos també la fa idònia per a aquestes finalitats. En els darrers anys s’han desenvolupat noves estratègies mitjançant instrumentació HRMS híbrida. Aquests mètodes permeten l’anàlisi dirigit de compostos coneguts, l’escombratge de compostos sospitosos a partir de bases de dades i fins i tot l’anàlisi no dirigit de compostos desconeguts. Moltes d’aquestes capacitats han estat utilitzades per a detectar i identificar els TPs dels diferents processos estudiats en aquesta tesi. Al capítol 3 s’ha avaluat l’efecte de la llum del sol sobre els fàrmacs, considerat el principal mecanisme de transformació abiòtic. Concretament s’ha avaluat les reaccions de foto-transformació dels inhibidors de la fosfodiesterasa V mitjançant simulacions a escala laboratori. La avaluació conjunta de les rutes de degradació del sildenafil i els seus anàlegs ens ha permès determinar un patró de fragmentació comú i identificar els TPs principals pels diferents compostos. Finalment, s’han analitzat mostres ambientals per a detectar els TPs identificats. Aquest estudi a significat la primera detecció de dos TPs del SDF i/o dels seus anàlegs al medi ambient. Per tal d’estudiar també els processos de biodegradació causats per microorganismes, s’han determinat els principals TPs per biodegradació de sulfonamides a escala laboratori. En aquesta ocasió la identificació dels TPs es va utilitzar per a poder realitzar un estudi quantitatiu dels mecanismes de resistència bacteriana a les sulfonamides. Els resultats constaten que a altes concentracions el paper de la degradació de les sulfonamides és més important, mentre que a baixes concentracions la adaptació dels bacteris mitjançant la propagació de gens resistents als antibiòtics cobra protagonisme. Al capítol 4 s’ha avaluat l’exposició de fàrmacs als organismes aquàtics mitjançant la identificació de metabòlits. En primer lloc s’han identificat els metabòlits de l’Ibuprofè i la carbamazepina mitjançant la injecció intraperitoneal a llenguados. La comparació de mostres control i mostres tractades i l’estudi dels patrons de fragmentació ha permès proposar les identitats dels metabòlits. Aquesta aproximació a permès identificar temptativament 13 metabòlits de l’ibuprofè i 11 de la carbamazepina. A continuació s’han identificat els metabòlits de l’ibuprofè en plantes aquàtiques (Lemna Gibba). En total s’han identificat 11 metabòlits de l’ibuprofè. Aquests estudis han permès demostrar la variabilitat en el metabolisme en diferents organismes i com això fa més complexa la seva avaluació, ja que un compost pot resultar inofensiu per a una espècie i molt tòxic per a una altre. Finalment, s’ha estudiat el metabolisme dels fàrmacs en peixos salvatges mitjançant un mostreig al riu Llobregat. Inicialment s’ha realitzat un escombratge dirigit de més de 2000 contaminants orgànics. Això ens ha permès detectar més de 12 productes farmacèutics dels 150 que contenia la llista. Dels fàrmacs detectats s’han seleccionat 6 fàrmacs i a través d’un software de predicció de metabòlits s’ha generat una base de dades de 150 metabòlits. Amb aquesta llista s’ha realitzat un escombratge de sospitosos permeten la detecció d’un gran nombre de candidats dels que mitjançant l’estudi dels patrons de fragmentació s’ha proposat les seves estructures.
In this thesis, the main transformations of drugs in the aquatic environment have been studied, including biotic and abiotic processes. These studies have been performed using liquid chromatography coupled to high resolution mass spectrometry (LC-HRMS).The different approaches by LC-HRMS in environmental samples have been reviewed in chapter 1. In chapter 3 the phototransformation reactions of phosphodiesterase V inhibitors have been studied through laboratory-scale simulations. Through these studies, common fragmentation pattern and the major TPs were identified. Finally, this study reported the first detection of two TPs of SDF and/or its analogues in the environment. Chapter 3 also shows a study of biodegradation of sulfonamides and the identification of main TPs at laboratory scale. The results show that at high concentrations the role of sulphonamide degradation is more important, while at low concentrations the adaptation of bacteria through the propagation of antibiotic resistant genes is more relevant. In chapter 4, the exposure of different aquatic organisms and their different metabolism was evaluated. Laboratory-scale studies have been performed to determine the metabolites of ibuprofen in plant and fish. With these approaches, 13 metabolites of ibuprofen and 11 metabolites of carbamazepine have been tentatively identified in bile of treated fish and 11 metabolites of ibuprofen in aquatic plants. These studies have demonstrated the variability of different aquatic organisms for the biotransformation of IBU. Finally, target screening of more than 2000 organic pollutants was carried out in wild fish. This approach allowed us to detect 12 pharmaceuticals out of the 150 contained in this list. Then, a database of more than 150 metabolites corresponding to the transformations of six of these drugs, through metabolite prediction software, has been generated. Suspect screening approach has been carried out for the detection and identification of pharmaceutical metabolites.
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Perréard, Camille. "Surface functionalization strategies for the design of a lab-on-a-chip integrating an aptamer-based molecular capture for the analysis of emerging water contaminants." Thesis, Paris 6, 2015. http://www.theses.fr/2015PA066352/document.

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Développés pour améliorer la santé et le bien-être, certains composés pharmaceutiques sont désormais sous haute surveillance car considérés comme des contaminants émergents des eaux. Pour répondre à ce nouvel enjeu, nous visons à développer un microsystème d'analyse permettant l'identification et la quantification de ces contaminants dans des échantillons d'eau. L'aspect original de ce microsystème repose sur l'intégration au sein du canal d'une zone de préconcentration dans laquelle sont immobilisés des ligands (aptamères dans notre étude), permettant l'extraction sélective de la cible et sa concentration. Pour développer ce microsystème, deux types de fonctionnalisation de surface doivent être mis en œuvre : (1) globale, sur toute la surface des canaux, pour contrôler leurs propriétés de surface et ainsi éviter l'adsorption et contrôler les écoulements de liquides, et (2) locale, pour greffer les ligands sélectifs dans une zone confinée du canal. Les polymères COC et THV, prometteurs pour la conception de puces microfluidiques grâce à leur transparence dans le domaine UV-visible et leur excellente résistance aux solvants, ont été sélectionnés pour la microfabrication du système. Cependant, leur inertie chimique rend difficile la fonctionnalisation de leur surface, et de nouvelles méthodes de traitement de surface ont été développées. Nous présentons ainsi plusieurs méthodes innovantes pour la fonctionnalisation de ces matériaux, basées sur un dépôt plasma, une modification électrochimique et/ou une réaction chimique. La possibilité d'encapsuler les ligands dans une phase monolithique à l'intérieur d'un microcanal grâce à un procédé sol-gel a également été évaluée
Developed to promote human health and well-being, certain pharmaceuticals are now attracting attention as crucial emerging water contaminants. To deal with this concern, we aim at developing an analytical microsystem for the identification and quantitation of these contaminants in water samples. The original aspect of this lab-on-a-chip relies on the integration inside the channel of a preconcentration zone in which ligands (aptamer in our study) are immobilized, in order to concentrate the target and extract it from the rest sample matrix. Development of this microsystem requires surface treatments to modify the microchannel surface at two scales: (1) globally (on the entire channel walls) to control surface properties and thus avoid adsorption as well as control fluid flows, or (2) locally to immobilize selective ligands in restricted areas for selective target extraction and preconcentration. Polymers COC and THV, attractive for the conception of microfluidic chips thanks to their UV-visible transparency and high resistance to aggressive solvents, were selected as the microchip material. However due their chemical inertness new functionalization techniques have to be developed to modify their surface. In this work, innovative surface treatment strategies have been developed for both materials, based on plasma, electrochemical and chemical approaches. The possibility of encapsulating aptamers in a monolithic phase inside microchannel by sol-gel process was also explored
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Han, Changseok. "Monitoring and Removal of Water Contaminants of Emerging Concern| Development of A Multi-Walled Carbon Nanotube Based-Biosensor and Highly Tailor-Designed Titanium Dioxide Photocatalysts." Thesis, University of Cincinnati, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=3622058.

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In this dissertation, as a monitoring technology for cyanotoxins, a multiwalled carbon nanotube (MWCNT)-based electrochemical biosensor was developed to determine microcystin-LR (MC-LR), a potent cyanobacterial toxin, in sources of drinking water supplies. The performance of the MWCNT array biosensor is evaluated using micro-Raman spectroscopy, X-ray photoelectron spectroscopy, cyclic voltammetry, optical microscopy, and Faradaic electrochemical impedance spectroscopy. A linear dependence of the electron-transfer resistance on the MC-LR concentration is observed in the range of 0.05 to 20 µg L-1, which enables cyanotoxin monitoring well below the World Health Organization provisional concentration limit of 1 µg L-1 for MC-LR in drinking water.

In addition to the development of monitoring tools for cyanotoxins, visible light-activated (VLA) TiO2 and monodisperse TiO2 were developed and evaluated for treatment of water contaminants of emerging concern. These materials were synthesized using modified sol-gel methods (i.e., wet chemistry-based methods) such as self-assembly-based and ionic strength-assisted techniques. For this study, first, VLA-sulfur-doped TiO2 (S-TiO 2) nanocrystalline films were synthesized by a self-assembly-based sol-gel method using nonionic surfactant to control nanostructure and an inorganic sulfur source for decomposing MC-LR under visible light illumination. Second, the effects of solvent on the synthesis of VLA-S-TiO2 films were scrutinized. Four different polar, protic solvents, isopropanol, 1-butanol, ethanol, and methanol, were chosen as the solvent in four titania sol-gel preparations. Third, monodisperse anatase titania nanoparticles with controllable sizes (typically 10-300 nm) were synthesized using an efficient and straightforward protocol via fine tuning of the ionic strength in the devised sol-gel methodology. Finally, noble metal Ag-decorated, monodisperse TiO2 (TiO 2-Ag) aggregates were successfully synthesized by an ionic strength-assisted, simple sol-gel method and were used for the photocatalytic degradation of the pharmaceutical oxytetracycline (OTC) under both UV and visible light irradiation. With a self-assembly-based sol-gel method, nanostructured anatase S-TiO 2 with high surface area (> 100 m2 g-1) and porosity (> 30 %) was synthesized and the sample calcined at 350 oC demonstrated the highest visible light absorption and visible light-induced photocatalytic activity in the decomposition of MC-LR. The structural and morphological properties of S-TiO2 could be also tailor-designed using different solvents in the sol-gel synthesis, while inducing negligible effects on the sulfur doping and the visible light activation of TiO 2. Thus, it can be concluded that the enhancement of photocatalytic activity of S-TiO2 films can be achieved by judicious choice of the main solvent for the sol-gel method. With an ionic strength-assisted sol-gel method, monodisperse spherical anatase TiO2 (10-300 nm in diameter) as well as monodisperse TiO2-Ag aggregates with 350 nm of diameter were synthesized. For TiO2-Ag, its visible light absorption increased due to the presence of Ag on the surface of monodisperse TiO2, which resulted in the enhancement of the photocatalytic degradation of OTC under both UV-visible light and visible light irradiation compared to pure TiO2. There was an optimal Ag content to obtain the highest photocatalytic degradation of OTC. These newly developed materials demonstrated the efficient decomposition of water contaminants of emerging concern, especially MC-LR and OTC, under UV-visible light and visible light illumination.

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López, Serna Rebeca. "Análisis y destino de residuos farmacéuticos en aguas subterráneas, superficiales y residuales." Doctoral thesis, Universitat de Barcelona, 2013. http://hdl.handle.net/10803/128799.

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Los fármacos, compuestos químicos con actividad biológica, y sus productos de transformación, metabolitos y otros derivados en las plantas de tratamiento y en el medio ambiente, con actividad farmacológica remanente, son contaminantes antropogénicos que, en muchos casos, están llegando al medioambiente a través de las aguas residuales, y son las aguas superficiales el primer y principal compartimento ambiental destino. Este es un hecho que, en la actualidad, es ya ampliamente reconocido por la comunidad científica, tras el desarrollo de métodos de análisis capaces de la determinación de estos microcontaminantes en el medio ambiente, y su posterior aplicación en estudios de presencia en diferentes matrices ambientales. Los científicos, por lo tanto, están demandando medidas de control de los mismos por parte de las autoridades. Aunque tímidos, se están dando pasos adelante en materia legislativa en la lucha contra este tipo de contaminación, lo que muestra la toma de conciencia de la importancia en el control de las fuentes de entrada de estos contaminantes emergentes, así como de su eliminación del medioambiente. Esto conlleva un aumento importante en el número de estudios y, por lo tanto, en las muestras a procesar por parte de los laboratorios medioambientales. De ahí nace la necesidad de optimizar la eficiencia y competitividad de los métodos analíticos actuales, de manera que progresen en fiabilidad y sensibilidad, aumentando al mismo tiempo su versatilidad, así como su capacidad y rendimiento. El desarrollo tecnológico en el sector es muy rápido, y en general, es la comunidad científica la que evalúa en primer término la viabilidad y bonanza de las diferentes propuestas tecnológicas. Con la presente tesis se ha pretendido dar respuesta a estas necesidades. Así se ha llevado a cabo: - El desarrollo y validación de métodos analíticos para la determinación de fármacos y sus derivados en aguas medioambientales y residuales, mostrando las ventajas y puntos débiles de cada uno de ellos. En concreto, se han usado dos fuentes de fiabilidad, que no son excluyentes y pueden ser utilizadas simultáneamente. La primera ha consistido en la introducción de la automatización en el tratamiento de muestra, llevando al mínimo la manipulación de las muestras por parte del analista. La segunda ha consistido en la introducción de surrogados y patrones internos adecuados que han puesto de manifiesto las incidencias producidas durante el proceso analítico, para que hayan podido ser corregidas. Por otro lado, se han conseguido métodos que presentan una elevada sensibilidad para la determinación de los microcontaminantes objeto de estudio presentes a bajas concentraciones en matrices complejas. Para ello se ha utilizado espectrómetros de masas de triple cuadrupolo de última generación, que trabajando en modo SRM (Selected Reaction Monitoring), han proporcionado una muy buena sensibilidad, además de una elevada selectividad, que ha allananado el camino de la fiabilidad comentada anteriormente. Además, se apostó también, por el desarrollo de métodos con la suficiente versatilidad como para que hayan podido ser aplicados sobre cualquier tipo de agua ambiental dulce continental, tanto superficial como subterránea, así como a agua residual y potable, con el fin de propiciar la intercalación de muestras de diferente naturaleza analizadas consecutivamente en una misma tanda. Finalmente, se propusieron métodos dotados de una elevada capacidad, de manera que un solo método haya sido capaz de analizar el mayor número de residuos de interés posibles, incluyendo fármacos y sus derivados, metabolitos y otros productos de transformación. Pero a la vez, se ha conseguido un aumento en el rendimiento analítico de estos métodos, es decir, se ha logrado una disminución del tiempo de análisis por muestra y un aumento del número de muestras por día. Para esto se apostó claramente por la automatización, eliminando algunas etapas en el proceso analítico, lo que, además de redundar en fiabilidad como se ha comentado anteriormente, ha proporcionado métodos analíticos más cortos y autónomos y, por lo tanto, capaces de trabajar en ausencia del analista. Otra enfoque en esta dirección fue la utilización de cromatografía rápida. - Otra parte importante de la presente tesis, ha sido la aplicación posterior de los métodos desarrollados, en estudios medioambientales de elevado interés científico por su innovación. En concreto en los siguientes: A) Estudio del impacto medioambiental a escala real, en un escenario de reutilización de agua residual para el mantenimiento del caudal ecológico de un río mediterráneo. Además, se valoró el riesgo ecotoxicológico y de estrogenicidad en las muestras del río. B) Estudio de presencia de fármacos y sus productos de transformación en las aguas superficiales de la cuenca del río Ebro. C) Estudio de la distribución tridimensional y origen de residuos farmacéuticos (fármacos y sus productos de transformación) en las aguas subterráneas bajo la ciudad de Barcelona (España). D) Determinación enantiomérica de 13 residuos farmacéuticos quirales en las aguas superficiales de la cuenca del río Guadalquivir, así como en las aguas de entrada y salida a las principales EDARs asociadas a la cuenca. Además, se discutieron las implicaciones en la toxicidad de las relaciones racémicas y no racémicas.
Pharmaceuticals are compounds with biological activity and their transformation products with remaining activity are arriving the environment through sewage waters, and superficial waters are the main receiving compartment. Some steps towards the fight this kind of contamination. This is creating an increase in the number of studies, and therefore, in the number of samples to be processed by the environmental laboratories. For this reason, the need to optimize the efficiency of current analytical methods, by improving the reliability, sensitivity, versatility, capacity and throughput, is a must. Technologic development is very fast in the sector, and the scientific community is generally the one that first assesses it. This thesis has tried to give answer to these requests. Thus, four multi-residue analytical methods for the analysis of pharmaceuticals and their transformation products in environmental and sewage waters, have been developed making use of cutting edge technology. The advantages and disadvantages of each of them have been discussed. Different online and offline pre-treatment technologies, fast and conventional liquid chromatographies and several kinds of triple quadrupoles for mass spectrometry, have been tested. Other important part of this thesis has been the application of the developed methods with high scientific studies, as follows: - Impact of the discharge of reclaimed sewage water in a Mediterranean river, and assessment of the eco-toxicological consequences. - Presence of pharmaceuticals and their transformation products in Ebro River basin, one of the main ones in the Iberian Peninsula. - Three-dimensional distribution of pharmaceuticals and their transformation products in the ground waters underlying Barcelona city (Spain). - Enantimeric determination of 13 chiral pharmaceutical residues in Guadalquivir River basin, one of the main ones in the Iberian Peninsula, and the assessment of the eco-toxicity issues related.
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36

Cruz, Alcalde Alberto. "Contribution to Performance Characterization and Kinetic Modelling of Micropollutants Abatement in Water and Wastewater by Ozone-based Oxidation Processes." Doctoral thesis, Universitat de Barcelona, 2019. http://hdl.handle.net/10803/667016.

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Ozonation is nowadays a competent technology for micropollutant oxidation in wastewater effluents. The combination of ozone with hydroxyl radical formed through ozone decomposition is effective in the abatement of a number of organic compounds. However, there are still some points to be addressed for a more efficient application of ozone-based processes to wastewater treatment and reclamation. There are, for instance, several organic compounds that react very slowly with ozone. They are known as ozone-resistant micropollutants. If a high quality water is wanted to be obtained, these substances should be also removed from the effluent. In addition, modelling the abatement of micropollutants during wastewater ozonation is essential for process simulation, optimization and real-time control. To make this possible, performance characterization in terms of oxidation efficiency is required, as well as some kinetic information regarding the abatement of micropollutants. The first can be addressed by using normalizing parameters allowing the estimation, for instance, of hydroxyl radical availability as a function of the consumed ozone, or any other parameter whose measurement during the process is simple. The most accurate way of obtaining kinetic data of micropollutants oxidation is conducting individual studies on this chemicals degradation by ozone and hydroxyl radicals. Some complementary tests, in addition, may be useful to obtain valuable data regarding the mechanisms of degradation and the potential ecotoxicological effects of formed transformation products. This thesis was divided in two parts: first, individual batch ozonation studies of selected concerning micropollutants were conducted. Particularly, the pesticides methiocarb, acetamiprid and dichlorvos were selected for that work. The second part consisted of the application of single ozonation and the combination O3/H2O2 was tested in the removal of ozone-refractory micropollutants from actual wastewater effluents. The latter was done through semi-batch ozonation experiments. The objectives were, on one hand, obtaining kinetic, mechanistic and toxicological data of some priority/emerging concern chemicals. On the other, ozonation studies with real effluent samples were performed with the aim of exploring the removal of ozone-recalcitrant chemicals and potential strategies for the modelling and real-time control of this process. In addition, improvement strategies for O3/H2O2 process application were investigated. Different kinetics were observed for pesticides reaction with ozone, being acetamiprid the most recalcitrant compound. In addition, toxicity of some of the pesticides transformation products was revealed, especially in the case of methiocarb degradation. Regarding ozone-based processes application to actual wastewater effluents, the removal of model ozone-recalcitrant compounds was found difficult, concluding that ozone doses higher than the immediate ozone demand (IOD) value are required for a more effective abatement of these substances regardless of the process employed. In the case of the O3/H2O2 process application, dosing hydrogen peroxide simultaneously to ozone bubbling was found to potentially entail important energy savings related to oxidants use. The oxidation performance of ozone-based processes and thus the abatement of ozone-refractory compounds could be effectively modelled using kinetic parameters, the monitoring of water quality parameters and empirical relationships obtained for each effluent. Furthermore, side reactions of involved oxidants with effluent organic compounds was found to increase the content in small and oxidized organic compounds in all cases. In the case of effluents containing suspended solids, ozone application also caused a net increase in the dissolved organic load.
El proceso de ozonización constituye una de las tecnologías de tratamiento de aguas con mayor potencial para la eliminación de microcontaminantes de los efluentes de depuradoras municipales. Pese a ello, algunos aspectos como la eliminación de aquellos contaminantes resistentes al ataque del ozono y la modelización cinética de este proceso ofrecen aún amplias posibilidades de mejora. La formación de productos de transformación a partir de reacciones del ozono y el radical hidroxilo con la materia orgánica del efluente es otro aspecto escasamente considerado. Dados los problemas técnicos y ambientales que dichos subproductos pueden ocasionar, la investigación de este fenómeno es también de gran interés. En esta tesis se estudiaron en primer lugar los fundamentos (cinética, mecanismos de reacción y efectos toxicológicos de los productos de transformación) del proceso de degradación de tres microcontaminantes orgánicos de preocupación emergente mediante el proceso de ozonización. A continuación, éstos y otros compuestos típicamente detectados en aguas residuales urbanas se emplearon como sustancias modelo en el estudio de la aplicación del ozono en efluentes reales de depuradora de calidad variada, con el fin de evaluar la eficiencia del proceso y proponer estrategias para la modelización del mismo. En este sentido, se propuso la combinación de parámetros cinéticos y la monitorización de parámetros de calidad del agua para el control a tiempo real del proceso. Las predicciones de eliminación de contaminantes llevadas a cabo mediante esta metodología mostraron una gran concordancia con los datos experimentales, tanto para el proceso de ozonización simple como para la combinación ozono-peróxido de hidrógeno, que por otro lado exhibió una gran eficiencia en la eliminación de contaminantes resistentes al ozono cuando se aplicó con dosificación simultánea de ambos oxidantes. Finalmente, la evaluación de los cambios experimentados por la materia orgánica del efluente durante la aplicación del ozono reveló una acumulación de compuestos de bajo peso molecular en todas las aguas ensayadas, además de la solubilización de materia orgánica en suspensión en efluentes con mayor carga orgánica.
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37

Bunch, Aubrey R. "Abundance of nonprescription pharmaceuticals in central Indiana streams and effects on sediment microbial activity." Muncie, IN : Ball State University, 2009. http://cardinalscholar.bsu.edu/640.

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38

Beltran, Carbó Antoni. "Synthesis of novel molecularly imprinted polymers and their application to the solid-phase extraction of water-based matrices." Doctoral thesis, Universitat Rovira i Virgili, 2010. http://hdl.handle.net/10803/9049.

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La present tesi s'ha desenvolupat dintre de la línia de recerca que el grup té sobre el desenvolupament de nous sorbents polimèrics per a aplicar-los com a sorbents en extraccions en fase sòlida.
En aquest cas, els sorbents sintetitzats són altament selectius per a la molècula d'interès i es coneixen com a sorbents d'empremta molecular.
Pel que fa al mètode de síntesi s'han explorat diferent tipus de polimeritzacions així com diferents tipus d'interacció entre els components que constitueixen el polímer a fi de millorar tant el procés de síntesi com el reconeixement de la molècula objectiu un cop obtingut el polímer per tal d'obtenir extraccions altament selectives.
Aquest sorbents s'han aplicat per a l'extracció de compostos considerats com a contaminants orgànics emergents en mostres tant d'orina humana com aigües de riu o de depuradora amb resultats satisfactoris en tots els casos, demostrant que aquest sorbents són una bona opció a l'hora de realitzar extraccions altament selectives.
The present thesis has been developed within the research trend that the group has on the development of new polymeric materials for their used as sorbents in solid-phase extraction.
In this case, the sorbents synthesised are highly selective for the molecule of interest and are known as molecularly imprinted polymers.
Regarding the synthesis of these polymers, several polymerisation protocols as well as several kinds of interactions that can be established between all the components involved in the synthesis of the polymers have been exploited.
The sorbents obtained were further applied in the selective extraction of several compounds framed within the group of emerging organic pollutants from human urine, river water or effluent water from sewage plants. In any case, a successful extraction of the target analyte was easily achieved by using any of the sorbents developed, thus proving that these sorbents are a good option when aiming to selectively extract the compound of interest from highly complex matrices.
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39

Kwok, Wing-hin Kevin Patrick, and 郭穎軒. "On the derivation of Water and Sediment Quality Guidelines: some pressing issues and theirresolutions." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2009. http://hub.hku.hk/bib/B42181963.

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40

Souza, Maiara Priscilla de. "Determinação de contaminantes emergentes em água utilizando microextração adsortiva em barra (BAμE) e UHPLC-MS/MS." Universidade Federal de Santa Maria, 2016. http://repositorio.ufsm.br/handle/1/10632.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
The emerging pollutants are substances that enter continuously in the environment and are being more recognize due to the advancement of instrumental and sample preparation techniques. These contaminants include several chemical classes, such as pharmaceuticals, hormones, personal care products, flame retardants and others. Water is one of the most susceptible matrix since the sewage discharge is one of the main routes of environmental pollution. Bar adsorptive microextration (BAμE) has shown great analytical capacity for the analysis of organic compounds in residual level and has become a well-established analytical tool in sample preparation. In this work, a simple and low cost method was validated for the analysis of 13 emerging contaminants in water using BAμE with polymeric sorbent followed by ultra high performance liquid chromatography with tandem mass spectrometry (UHPLC-MS/MS). The preparation, stability tests and development of BAμE devices are also discussed. Eleven different coating phases were evaluated. In order to select the best combination of experimental conditions for extraction and back extraction, central composite design (CCD) with four variables was applied. Validation results were satisfactory, since the method presented recoveries between 74% and 118% with relative standard deviations (RSD) < 19%. The analytical performance presented detection and quantification limits of 0.012 to 0.6 and 0.04 to 2 μg L-1, respectively. The proposed method combines a simple and effective sample preparation for the determination of emerging contaminants in water using a microextraction technique (BAμE) followed by UHPLC-MS/MS analysis. The method applicability was evaluated using real samples of surface, drinking and tap water and 6 positive samples were found indicating the presence of bisphenol A (0.08-0.665 μg L-1) and paracetamol (0.104-4.2 μg L-1).
Os contaminantes emergentes são substâncias que entram continuamente no meio ambiente e que estão sendo reconhecidas com maior profundidade devido ao avanço de técnicas instrumentais e de preparo de amostra. Estes compostos englobam diversas classes químicas, como por exemplo, fármacos, hormônios, produtos de higiene e cuidado pessoal, retardantes de chama, dentre outros. Uma das matrizes mais suscetíveis à contaminação é a água tendo em vista que a descarga de esgoto é uma das principais vias de poluição ambiental. A microextração adsortiva em barra (BAμE) tem demonstrado grande capacidade analítica para a análise de compostos orgânicos em nível residual e vem se tornando uma ferramenta analítica bem estabelecida no âmbito de preparo de amostras. Neste estudo foi desenvolvido e validado um método simples e de baixo custo para a determinação de 13 contaminantes emergentes em água utilizando BAμE e empregando sorvente polimérico com posterior análise por cromatografia liquida de ultra eficiência acoplada à espectrometria de massas em série (UHPLC-MS/MS). O preparo das barras bem como os testes de estabilidade foram avaliados. Onze sorventes foram testados para revestir os dispositivos. A fim de avaliar a melhor combinação de parâmetros para a extração e dessorção dos analitos, utilizou-se um planejamento do composto central (CCD) com 4 variáveis. Os resultados da validação foram satisfatórios uma vez que as recuperações obtidas ficaram entre 74% e 118% com desvio padrão relativo RSD < 19%. Os limites de detecção e quantificação foram de 0,012 a 0,6 e 0,04 a 2,0 μg L-1, respectivamente. O método proposto combina uma etapa de preparo de amostra simples e eficaz para a determinação de contaminantes emergentes em água. A aplicabilidade do método foi avaliada utilizando amostras reais de água de superfície, de torneira e mineral e destas, 6 amostras apresentaram bisfenol A (0,08-0,665 μg L-1) e paracetamol (0,104-4,2 μg L-1).
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41

Ademoyegun, Olufemi Temitope. "Evaluation of some pharmaceutical and personal care products and pesticide residues in selected wastewater treatment plants and receiving watersheds in Eastern Cape, South Africa." Thesis, University of Fort Hare, 2017. http://hdl.handle.net/10353/2922.

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Emerging organic contaminants (EOCs) have been the focus of global environmental research for over three decades. EOCs have caused widespread concern due to their extensive use. As EOCs were designed to correct, enhance or protect a specific physiological, their target effects in humans and/or farm stocks are relatively well known and documented. However, there is limited knowledge about their unintended effects in the environment. To address the occurrence, distribution and fate of EOCs in the environment, efficient and reliable analytical methods are needed. The relatively low concentration, high polarity, and thermal lability of some EOCs, together with their interaction with complex environmental matrices, make their analysis challenging. Sample preparation followed by GC or HPLC separation and mass spectrometry (MS) detection has become the standard approach for evaluating EOCs in environmental samples. Physicochemical properties of EOCs range from highly water-soluble (hydrophylic) to highly water-insoluble (hydrophobic). Two groups of these EOCs were considered for study in this work. Pharmaceutical and personal care products (PPCPs) were comprehensively studied in five wastewater treatment plants and their receiving watersheds in Amathole districts in Eastern C ape, South Africa. PPCPs have been widely reported in wastewater influents, effluents, receiving rivers and biosolids, but reports of their occurrence in all these matrixes have been limited by the difficulty of analysis. Therefore, a comprehensive validation of methods was carried out on the influents, effluents, sludge and soil from the irrigated golf course where the effluent of one of the study sites was being used for over three decades now for irrigation. In all, thirteen PPCPs from five therapeutic groups were selected for study in this work because of their administering rate and availability of analytical instrument. Good limit of detection (LOD) and limit of quantification (LOQ) were achieved for the method used. The LOD for the aqueous Three different technologies were employed for the treatment of wastewater in the five selected wastewater treatment plants (WWTPs) and study was carried out to evaluate their ability to eliminate the selected compounds from the influents to the effluents using statistical analysis (ANOVA) at p<0.05 on the percentage removal rate across the three plants. The results had shown eight of the compounds having no significant difference among the treatment operations, whereas the remaining five compounds varied significantly among the treatment technologies under investigation. Principal component analysis was performed on the concentration of PPCPs, their removal rate and also on the physicochemical and treatment operation parameters. Hydraulic retention time (HRT) had correlation coefficient, r = 0.90 with the concentration of PPCPs and removal rates. Furthermore, occurrences, seasonal variation, mean concentration distribution pattern of the compounds, and temporal evaluation of the mean concentration of the pharmaceutical compounds in the five WWTPs during one year of sampling were considered. The results revealed that five products which were diclofenac, ibuprofen, paracetamol, triclosan and diethyl toluamide (DDET) were predominant among the PPCPs in all the WWTPs. The removal efficiency was highest in caffeine with 96 percent, and the lowest was obtained with carbamazepine (4 percent). Risk quotient of the concentration of PPCPs in the effluents and receiving waters was determined to assess their chronic toxicity at three trophic levels: fish, algae and matrixes studied ranged from 0.01 μg/L to 0.25 μg/L, and the LOQ from 0.02 μg/L to 0.78 μg/L. In the solid matrixes, LOD varied from 0.01 ng/g to 0.65 ng/g, and the LOQ between 0.08 ng/g and 5.17 ng/g. Better recovery efficiency was obtained with this mixture of solvents, acetone: dichloromethane (1:1), for the recovery of the five therapeutic groups in the solid matrixes using ultrasonication- assisted techniques. The results show percentage recovery values ranging from 68.8 percent to 107.5 percent diaphian. According to the environmental risk assessment results, ibuprofen and triclosan were found to be the most critical compounds due to their high risk quotient values. These findings will, therefore, help in the future evaluation of the efficiency of different treatment technologies in the removal of various PPCPs from the wastewater and their sustainable management in the aquatic resources in Eastern Cape, South Africa. For the lipophilic organochlorine pesticides (OCPs), the limits of detection (LODs) of the tested congeners varied from 0.04 ng/g (α-BHC) to 0.49 ng/g (endosulfan sulfate) and the limits of quantification ranging from 0.22 ng/g (aldrin) to 2.17 ng/g (δ-BHC).
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42

Pescara, Igor Cardoso 1983. "Ocorrência e remoção de contaminantes emergentes por tratamentos convencionais de água e esgoto." [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/249647.

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Orientador: Wilson de Figueiredo Jardim
Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Química
Made available in DSpace on 2018-08-26T13:39:08Z (GMT). No. of bitstreams: 1 Pescara_IgorCardoso_D.pdf: 5286232 bytes, checksum: 74793adc4ea590e2eb8fdeb51a796399 (MD5) Previous issue date: 2014
Resumo: Este trabalho teve como objetivo avaliar a eficiência dos tratamentos empregados em cinco estações de tratamento de esgoto (ETE) e duas estações de tratamento de água (ETA) na remoção dos hormônios endógenos estrona (E1), 17?-estradiol (E2), estriol (E3), testosterona (TTN) e progesterona (PROG), hormônios sintéticos 17a-etinilestradiol (EE2), dietilestilbestrol (DES), norgestrel (NGT) e mestranol (MEE), produtos de uso industrial bisfenol A (BPA), fenolftaleína (PhPh), n-nonilfenol (nNP), n-octilfenol (nOP) e triclosan (TCS), o fármaco cafeína (CAF) e o pesticida atrazina (ATZ). Foi possível quantificar BPA, E1, E3, CAF e ATZ em esgoto bruto e BPA, E1, CAF e ATZ em água bruta. Para cada composto, tanto os tratamentos realizados pelas ETE quanto os realizados pelas ETA apresentaram eficiências de remoção variáveis. A cafeína foi o composto-alvo mais frequentemente encontrado nas amostras, sendo escolhida como indicador químico para avaliar a eficiência dos tratamentos. Foi encontrada uma taxa média de 99% para a remoção de CAF pelas ETE, sendo as etapas com tratamentos biológicos as mais eficientes. Os tratamentos anaeróbios apresentaram remoções médias superiores a 80% na remoção de CAF, e os tratamentos aeróbios foram capazes de remover cerca de 20% da carga do composto. Nas ETE, os tratamentos de coagulação e desinfecção foram pouco eficientes nas remoções dos compostos-alvo. Já para as ETA, foram observadas remoções de até 80% de CAF pelos tratamentos empregados, sendo a etapa de coagulação a responsável pela maior remoção de CAF da água bruta. A etapa de filtração em carvão ativado apresentou eficiências de remoção menores que 10%, enquanto a desinfecção demonstrou baixa eficiência na remoção de CAF. Na cidade de São José do Rio Preto ¿ SP foi possível quantificar, ao menos uma vez, BPA, E1, E3, PhPh, CAF, TCS e ATZ em água superficial, BPA, TCS e CAF em água subterrânea e BPA, CAF e ATZ em água de abastecimento.
Abstract: Water and wastewater conventional treatments are often considered inefficient to remove micropollutants. The aim of this work was to evaluate the removal efficiency of the endogenous hormones estrone (E1), 17? estradiol (E2), estriol (E3), testosterone (TTN), and progesterone (PROG), the synthetic hormones 17a-ethinylestradiol (EE2), diethylstilbestrol (DES), norgestrel (NGT), and mestranol (MEE), the industrial chemicals bisphenol A (BPA), phenolphthalein (PhPh), n nonylphenol (nNP), n octylphenol (nOP), and triclosan (TCS), the pharmaceutical caffeine (CAF), and the pesticide atrazine (ATZ) by five wastewater treatment plants (WWTP) and two drinking water treatment plants (DWTP). The target compounds BPA, E1, E3, CAF, and ATZ were found in raw sewage, while BPA, E1, CAF, and ATZ in raw water. Both WWTP and DWTP treatments presented variable removal efficiency. Caffeine was the target compound more often detected in samples, thus it was chosen as a chemical indicator to evaluate treatment efficiencies. The average removal of CAF by WWTP was 99%, in which the biological treatment was more efficient. The anaerobic treatment presented an average removal of CAF above 80%, and around 20% for the aerobic treatments. Coagulation and disinfection treatments of WWTP showed low efficiency to remove the target compounds. DWTP treatment efficiency reached up to 80% removal, with coagulation step presenting highest removals of CAF. The activated carbon filtration showed removal efficiency under 10%, whereas the disinfection step presented low efficiency to remove CAF. At São José do Rio Preto city were found, at least once, BPA, E1, E3, PhPh, CAF, TCS, and ATZ in surface water; BPA, TCS, and CAF in groundwater, and BPA, CAF, and ATZ in drinking water
Doutorado
Quimica Analitica
Doutor em Ciências
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43

Čelić, Mira. "Target analysis and suspect screening of wastewater derived contaminants in receiving riverine and coastal areas and assessment of environmental risks." Doctoral thesis, Universitat de Girona, 2020. http://hdl.handle.net/10803/671225.

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The main objective of this thesis is to evaluate the impact of wastewater discharges on receiving riverine and coastal ecosystems by studying the occurrence and fate of emerging contaminants (ECs). Since there is a myriad of ECs present in the environment, this thesis mostly focused on two main groups of compounds: (i) endocrine disrupting compounds (EDCs), including natural and synthetic hormones, alkylphenols (APs), such as nonylphenol (NP) and octylphenol (OP), and the plasticizer bisphenol A (BPA), and (ii) pharmaceutically active compounds (PhACs). These compounds were selected because they are one of the ECs of major input into the environment, thus being considered as “pseudo-persistent” pollutants, and for their potential deleterious effects to non-target organisms. Besides these target ECs, this thesis also evaluated the occurrence of other groups of contaminants by using high resolution mass spectrometry (HRMS). Finally, an assessment of the environmental risks posed by the identified ECs has been done in order to select the compounds of major ecological concern and those that could be used as relevant markers of wastewater contamination in freshwater and marine ecosystems. To accomplish the thesis objectives, two different analytical approaches have been used: (i) quantitative target analytical methods to determine the two groups of selected ECs (13 target EDCs and 81 PhACs that belong to nineteen different therapeutic groups) using reference analytical standards, and (ii) suspect screening using HRMS and exact mass compound databases (360 ECs)
La finalitat principal d'aquesta tesi és l’avaluació de l'impacte de les aigües residuals en els ecosistemes d'aigua dolça i costaners, mitjançant l'estudi de la presència i destí de contaminants emergents (CEs). Atès que hi ha una gran quantitat de CEs presents en el medi ambient, aquesta tesi s'ha centrat principalment en dos grups de contaminants: (i) compostos disruptors endocrins (EDC), que inclouen les hormones naturals i sintètiques, alquilfenols (AP), com el nonilfenol (NP) i el octilfenol (OP), i el plastificant bisfenol A (BPA); ii) fàrmacs (PhACs). Aquests compostos es van seleccionar perquè pertanyen als CEs amb major entrada al medi ambient, de manera que es consideren com a contaminants "pseudo persistents", a banda dels seus possibles efectes adversos per als organismes aquàtics. Apart d'aquests CEs, en aquesta tesi també s’ha estudiat la presència d'altres grups de contaminants mitjançant l'ús d'espectrometria de masses d'alta resolució (HRMS). Finalment, s'ha realitzat una avaluació dels riscos plantejats per la presència dels CEs identificats, amb l'objectiu de seleccionar els compostos de major rellevància ecològica i que es podrien utilitzar com a marcadors de contaminació d'aigües residuals en els ecosistemes d'aigua dolça i marins. Per aconseguir aquests objectius, s'han utilitzat dos enfocaments analítics diferents: (i) l’ús de mètodes analítics target per determinar els dos grups de CEs seleccionats (13 EDCs i 81 PhACs que pertanyen a dinou grups terapèutics diferents), utilitzant estàndards analítics de referència; (ii) suspect screening mitjançant l’ús de HRMS i bases de dades de massa exactes (360 ECs)
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44

Heuett, Nubia Vanesa. "Target and Non-target Techniques for the Quantitation of Drugs of Abuse, Identification of Transformation Products, and Characterization of Contaminants of Emergent Concern by High Resolution Mass Spectrometry." FIU Digital Commons, 2015. http://digitalcommons.fiu.edu/etd/2194.

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Development and application of target and non-target techniques for routine analysis, identification of transformation products, and characterization of unknown compounds in water matrices using liquid-chromatography high-resolution mass spectrometry (HRMS) were explored in this dissertation. A novel analytical method based on online-SPE-LC-HRMS was developed for the detection of 18 drugs of abuse (DOAs) in raw sewage water from a college campus. Results showed the presence of 14 DOAs for which amphetamine and 11-nor-9-carcoxy-THC (THC metabolite) were the most prevalent and had the highest potential consumption rates. A second study dedicated to the identification of transformation products (TPs) generated from DOAs was conducted using a combination of HR-MS/MS and metabolic identification and structural elucidation software. Findings confirmed the presence of multiple phase I and II DOA TPs (n=35) in raw sewage influents. Concentrations of all TPs were estimated based on the parent DOAs response factors, and used to calculate the percent mole fraction contributions of each TP to the parent concentrations. High abundance and frequency (compared to the parent drug) was determined for 9 of the TPs coming from drugs like oxycodone, morphine, codeine, methadone, LSD, cocaine, and MDEA. Non-target analysis using HRMS was explored as a tool to characterize, and compare a series of interconnected water matrices along a river system. Several thousands of formulae were generated using automated heuristic rules from the full-scan acquisition at 140,000 resolution. Samples were part of a trajectory covering upstream, effluent, effluent mixing zone, downstream, drinking water intake, and treated drinking water locations. Graphical representations of the data were used to evaluate commonalities among the system. Using this approach, a total of 64 recalcitrant components were identified throughout the samples downstream of the effluent release point. Using a combination of MS/MS and computer-aid software techniques 4 out of the 64 compounds were tentatively confirmed. In addition, comparison of drinking water intake and finalized treated drinking water sites showed the presence of 1,152 chemical entities that were common to both locations; and 1,857 that were unique to the treated drinking water. Therefore, this non-target technique could be used to identify the potential formation of treatment byproducts.
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45

Minakata, Daisuke. "Development of aqueous phase hydroxyl radical reaction rate constants predictors for advanced oxidation processes." Diss., Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/37127.

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Emerging contaminants are defined as synthetic or naturally occurring chemicals or microorganisms that are not currently regulated but have the potential to enter the environment and cause adverse ecological and/or human health effects. With recent development in analytical techniques, emerging contaminants have been detected in wastewater, source water, and finished drinking water. These environmental occurrence data have raised public concern about the fate and ecological impacts of such compounds. Concerns regarding emerging contaminants and the many chemicals that are in use or production necessitate a task to assess their potential health effects and removal efficiency during water treatment. Advanced oxidation processes (AOPs) are attractive and promising technologies for emerging contaminant control due to its capability of mineralizing organic compound via reactions with highly active hydroxyl radicals. However, the nonselective reactivity of hydroxyl radicals and the radical chain reactions make AOPs mechanistically complex processes. In addition, the diversity and complexity of the structure of a large number of emerging contaminants make it difficult and expensive to study the degradation pathways of each contaminant and the fate of the intermediates and byproducts. The intermediates and byproducts that are produced may pose potential effects to human and aquatic ecosystems. Consequently, there is a need to develop first-principle based mechanistic models that can enumerate reaction pathway, calculate concentrations of the byproducts, and estimate their human effects for both water treatment and reuse practices. This dissertation develops methods to predict reaction rate constants for elementary reactions that are identified by a previously developed computer-based reaction pathway generator. Many intermediates and byproducts that are experimentally identified for HO* induced reactions with emerging contaminants include common lower molecular weight organic compounds on the basis of several carbons. These lower carbon intermediates and byproducts also react with HO* at relatively smaller reaction rate constants (i.e., k < 109 M-1s-1) and may significantly affect overall performance of AOPs. In addition, the structures of emerging contaminants with various functional groups are too complicated to model. As a consequence, the rate constant predictors are established based on the conventional organic compounds as an initial approch. A group contribution method (GCM) predicts the aqueous phase hydroxyl radical reaction rate constants for compounds with a wide range of functional groups. The GCM is a first comprehensive tool to predict aqueous phase hydroxyl radical reaction rate constants for reactions that include hydrogen-atom abstraction from a C-H bond and/or a O-H bond by hydroxyl radical, hydroxyl radical addition to a C=C unsaturated bond in alkenes and aromatic compounds, and hydroxyl radical interaction with sulfur-, nitrogen-, or phosphorus-atom-containing compounds. The GCM shows predictability; factor of difference of 2 from literature-reported experimental values. The GCM successfully predicts the hydroxyl radical reaction rate constants for a limited number of emerging contaminants. Linear free energy relationships (LFERs) bridge a kinetic property with a thermochemical property. The LFERs is a new proof-of-concept approach for Ab initio reaction rate constants predictors. The kinetic property represents literature-reported and our experimentally obtained hydroxyl radical reaction rate constants for neutral and ionized compounds. The thermochemical property represents quantum mechanically calculated aqueous phase free energy of activation. Various Ab initio quantum mechanical methods and solvation models are explored to calculate the aqueous phase free energy of activation of reactantas and transition states. The quantum mechanically calculcated aqueous phase free energies of activation are within the acceptable range when compared to those that are obtained from the experiments. These approaches may be applied to other reaction mechanisms to establish a library of rate constant predictions for the mechanistic modeling of AOPs. The predicted kinetic information enables one to identify important pathways of AOP mechanisms that are initiated by hydroxyl radical, and can be used to calculate concentration profiles of parent compounds, intermediates and byproducts. The mechanistic model guides the design of experiments that are used to examine the reaction mechanisms of important intermediates and byproducts and the application of AOPs to real fields.
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46

Sagristà, i. Puig Ester. "Hollow fiber liquid-phase microextraction in the determination of pharmaceuticals and personal care products." Doctoral thesis, Universitat de Girona, 2012. http://hdl.handle.net/10803/101412.

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Extensive amounts of pharmaceuticals and personal care products (organic emerging pollutants) are introduced into the environment mainly through wastewater treatment plants discharges either effluent wastewater reaching into the aquatic environment or sewage sludge which is spread onto agricultural land. These compounds are not regulated and their negative effects on humans and wildlife are unknown. One of the main challenges of analytical chemistry is to develop selective and sensitive methods for the detection and quantitation of pharmaceuticals and personal care products and their transformation products in complex matrices. The research presented in the thesis is focused on the development of new methods based on the use of hollow fiber liquid- phase microextraction (HF-LPME) technique and liquid chromatography for the determination of some of the most consume pharmaceuticals and personal care products in wastewaters, environmental waters and sewage sludge.
Tones de substàncies biològicament actives són alliberades contínuament al medi ambient, a través de la descàrrega d’aigües residuals als medis aquàtics o de biosòlids en l’agricultura. La presència d’aquestes substàncies (contaminants emergents) en el medi ambient ha generat una gran preocupació perquè es desconeix com actuen i quins són els mecanismes implicats en la seva transformació i/o transport. Un dels reptes de la química analítica és dissenyar mètodes selectius i sensibles per a la determinació de contaminants emergents en matrius complexes. La recerca presentada en aquesta tesi es centra en el desenvolupament de nous mètodes analítics basats en l’ús de la microextracció enfase líquida amb fibra buida (HF-LPME) i la cromatografia líquida per a la determinació d’alguns fàrmacs i productes d’higiene personal en aigües residuals, medis aquàtics i biosòlids.
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47

Nieto, Cebrián Antonio. "Emerging organic contaminants in sewage sludge." Doctoral thesis, Universitat Rovira i Virgili, 2010. http://hdl.handle.net/10803/9048.

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El objetivo de esta tesis es el desarrollo de métodos analíticos para la determinación de un grupo de contaminantes emergentes entre los cuales se incluyen los fármacos y los compuestos de cuidado personal en lodos de depuradora.
Los métodos desarrollados se basan en la extracción presurizada con solventes (PLE) y, debido a la polaridad de estos contaminantes, la cromatografia de líquidos. Como técnicas de detección se han utilizado la espectrometría de masas (con quadrupolo y tiempo de vuelo como analizadores) y la espectrometría de masas en tandem (con triple quadrupolo como analizador) utilizando la interfase de electrospray.
A parte del desarrollo de los métodos para la determinación de fármacos, hormonas y compuestos de cuidado personal, se han analizado muestras de dos plantas de tratamiento de aguas residuales de la zona de Tarragona. Se han obtenido resultados de la presencia de estos compuestos en lodos de depuradora que hasta la fecha no existían sobre las muestras de esta zona.
The scope of this thesis is to develop analytical methods to determine a group of pharmaceuticals and personal care products included in the list of so called "emerging organic contaminants".
The methods are based on pressurized liquid extraction as extraction technique and due to the polarities of these contaminants, liquid chromatography was the selected separation technique. Because the low concentration of these contaminants in sewage sludge, sensitive and selective detection technique have to be used such as mass spectrometry (with quadruople or time of flight analyzers) and tandem mass spectrometry (with triple quadrupole analyzer) using in all cases the electrospray interface.
The methods developed have been used to monitor several groups of pharmaceuticals and personal care products from sewage sludge from two different sewage treatment plants. The samples have been collected in Tarragona, where no studies related to the control of these compounds have been done.
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48

Núñez, Marcé Mireia. "Emerging organic contaminants in aquatic organisms." Doctoral thesis, Universitat Rovira i Virgili, 2017. http://hdl.handle.net/10803/456825.

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Aquesta Tesi Doctoral se centra en el desenvolupament de nous mètodes analítics per determinar diferents contaminants orgànics emergents, com ara productes farmacèutics de consum generalitzat, els medis iodat de contrast per a raigs-X (un altre grup de productes farmacèutics emprats en la medicina de diagnòstic), i un grup d'edulcorants d'alta intensitat en organismes aquàtics. Dues tècniques d'extracció (extracció mitjançant líquids pressuritzats i QuEChERS) van ser avaluades per extreure els compostos seleccionats i diferents neteges també van ser provades. La determinació es va realitzar mitjançant cromatografia de líquids acoblada a espectrometria de masses.D'altra banda, també es va dur a terme un estudi ecotoxicològic en l'espècie Gammarus pulex, on s' avaluà la toxicitat del triclosan en aquesta espècie i, a més a més, es van estudiar poblacions procedents de diferents ambients amb diferents graus de contaminació per determinar si la seva resistència era similar o no.
Esta tesis doctoral se centra en el desarrollo de nuevos métodos analíticos para determinar diferentes contaminantes orgánicos emergentes, como productos farmacéuticos de consumo generalizado, medios yodados de contraste para rayos-X (otro grupo de productos farmacéuticos empleados en medicina de diagnóstico) y un grupo de edulcorantes de alta intensidad en organismos acuáticos. Para ello se evaluaron dos técnicas de extracción (extracción con líquidos presurizados y QuEChERS) para extraer los compuestos seleccionados y también se ensayaron diferentes limpiezas. La determinación se realizó mediante cromatografía de líquidos acoplada a espectrometría de masas. Además, se realizó un estudio ecotoxicológico en la especie Gammarus pulex, donde se evaluó la toxicidad del triclosán para esta especie y, además, se estudiaron poblaciones procedentes de diferentes ambientes con diferentes grados de contaminación para determinar si su resistencia era similar o no.
This Doctoral Thesis focuses on the development of new analytical methods to determine different emerging organic contaminants such as pharmaceuticals of widespread consumption, iodinated X-ray contrast media (another group of pharmaceuticals employed in diagnostic medicine), and a group of high-intensity sweeteners, in aquatic organisms. To do so two extraction techniques (pressurised liquid extraction and QuEChERS) were evaluated to extract the selected compounds and different clean-ups were also tested. The determination was perfomed with liquid chromatography coupled with mass spectrometry. Moreover, another objective is to conduct an ecotoxicological study in the amphipod species Gammarus pulex, where the toxicity of triclosan to this species was evaluated. Moreover, populations that come from different environments with different degrees of pollution were evaluated in order to establish whether their resistance was similar or not.
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49

Andaluri, Gangadhar. "Ultrasound induced destruction of emerging contaminants." Diss., Temple University Libraries, 2011. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/111771.

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Civil Engineering
Ph.D.
There are many reports indicating the presence of emerging contaminants such as: estrogen hormones, 1,4-dioxane and perfluoro-octanoic acids in the natural environment. Estrogen hormones are considered important emerging class of contaminants due to their endocrine disrupting effects. These compounds are invariably found in the environment originating mostly from natural sources. Trace concentrations of estrogen hormones (low µg/L concentrations) have been detected in municipal wastewater treatment plants and observed in receiving water bodies. 1,4-Dioxane (C4H8O2) is used as an organic solvent and solvent stabilizer numerous in chemical processes. The United States Environmental Protection Agency (US-EPA) has recognized 1,4-dioxane as a toxic chemical and a possible human carcinogen. 1,4-dioxane has been detected as a contaminant in the natural environment, drinking water supplies, superfund sites, public groundwater sources in the United States, Canada and Japan at concentrations greater than the permissible standards. Perfluorinated chemicals such as perfluoro-octanoic acid (PFOA) and perfluorooctane-sulfonate (PFOS) have been manufactured for use in a variety of industrial and consumer applications. Due to their environmental persistence, PFOAs have been detected in surface waters at a number of locations at concentrations ranging from pg/L to ng/L. Elevated concentrations of PFOAs have been measured in surface and ground waters near specific point sources. Through this project, successful attempts have been made for the destruction of emerging contaminants using ultrasound. This study deals with the optimization of various process parameters for the destruction of estrogen hormones. The influence of process parameters such as power density, reactor geometry, power intensity, ultrasound amplitude, and external mixing was investigated. Artificial neural network (ANN) approach was used to describe the interactions between optimized parameters. The important findings obtained in the present work for the optimized estrogen degradation can help tackle the challenges of scale up such as operational optimization and energy consumption. The effect of process conditions such as pH and presence of oxidizing agents on the ultrasonic destruction of 1,4-dioxane and PFOA was studied. Acidic conditions favored the destruction of both the compounds. The presence of activated sulfate radicals enhanced the reaction rate kinetics. An innovative technology using electric potential and ultrasound for the removal organic contaminants was developed. The existence of organic contaminants in ionic form under certain process conditions has led to the development of this technology. Applying a low electric potential across the probe enhances the mass transfer of the contaminants into effective reaction zone, thereby enhancing the total destruction. A two-fold increase in the reaction rates was observed. This study shows ultrasound as an efficient and effective treatment technology for the destruction of emerging contaminants.
Temple University--Theses
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50

Mora, Gómez Julia. "Eliminación de contaminantes orgánicos emergentes mediante procesos electroquímicos de oxidación avanzada." Doctoral thesis, Universitat Politècnica de València, 2021. http://hdl.handle.net/10251/158751.

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[ES] La presente Tesis Doctoral se centra en el estudio del comportamiento electroquímico de nuevos electrodos cerámicos basados en SnO2 dopado con Sb2O3. El estudio está orientado a la posterior aplicación de estos electrodos en procesos electroquímicos de oxidación avanzada. Inicialmente, se consideraron diferentes temperaturas de sinterización (entre 1050°C y 1250°C) y se observó que un aumento en la temperatura de sinterización favorecía la deposición del Sb2O3 en la superficie anódica, disminuyendo así la resistividad del electrodo. Posteriormente, se estudió el comportamiento electroquímico de estos nuevos electrodos obteniendo el potencial de descarga del oxígeno mediante la técnica de voltametría de barrido lineal. Los resultados obtenidos revelaron que el valor del potencial de descarga del oxígeno disminuye con el aumento de la temperatura de sinterización. Además, estos electrodos presentaron un comportamiento intermedio entre el ánodo de Pt y el ánodo de BDD. Este último electrodo se emplea habitualmente en los procesos electroquímicos de oxidación avanzada debido a su elevada capacidad para generar radicales hidroxilo, los cuales son capaces de oxidar los compuestos orgánicos a dióxido de carbono y agua. A continuación, se llevaron a cabo ensayos de oxidación electroquímica con estos electrodos cerámicos para seleccionar la temperatura de sinterización. Los resultados mostraron que con el electrodo cerámico sinterizado a 1250°C se alcanza una menor degradación del compuesto orgánico, mientras que los electrodos sinterizados a menores temperaturas presentan un comportamiento similar entre ellos. Por tanto, se seleccionó el electrodo cerámico sinterizado a 1200°C ya que presenta una baja resistividad y un buen comportamiento electroquímico para ser utilizado como ánodo en los procesos electroquímicos de oxidación avanzada. Seguidamente se analizó la vida útil de estos electrodos cerámicos, y se comprobó que la matriz cerámica incrementa en gran medida la estabilidad a la polarización anódica de los electrodos basados en SnO2. Posteriormente, se llevaron a cabo procesos de electro-oxidación en modo galvanostático de distintos contaminantes difíciles de eliminar por las técnicas convencionales utilizando como ánodo los nuevos electrodos cerámicos y el electrodo de BDD, para así poder comparar los resultados obtenidos. Se observó que, aunque con los electrodos cerámicos se consigue degradar el 100% de los distintos contaminantes, el electrodo de BDD es el más eficiente ya que genera mayor cantidad de especies oxidantes activas en su superficie. Para un mismo electrodo, se observó que un aumento en la densidad de corriente aplicada mejora la velocidad de degradación y mineralización de cada contaminante, mientras que la eficiencia eléctrica disminuye. Por otro lado, se estudió el efecto de la presencia de una membrana de intercambio catiónico entre ánodo y cátodo. Los resultados mostraron que el uso de la membrana beneficia la degradación y la mineralización del contaminante, ya que mejora la cinética de reacción anódica y evita la reducción de las especies oxidantes electrogeneradas. A continuación, se analizó la influencia de la concentración del Na2SO4 como electrolito soporte. En este estudio se observó que un aumento en la concentración del Na2SO4 mejora la mineralización del contaminante para el electrodo de BDD y, por el contrario, empeora para el electrodo cerámico. Esto se debe a la capacidad de cada electrodo para oxidar los sulfatos a persulfatos. Por último, se llevaron a cabo ensayos de ecotoxicidad de las muestras tratadas, y se demostró que, en presencia de membrana, a mayor densidad de corriente y con el electrodo de BDD la toxicidad de la muestra es mayor debido a la mayor presencia en disolución de iones persulfato. Por tanto, con el electrodo cerámico, además de alcanzar un elevado grado de degradación del contamina
[CAT] La present Tesi Doctoral es centra en l'estudi del comportament electroquímic de nous elèctrodes ceràmics basats en SnO2 dopat amb Sb2O3. L'estudi està orientat a la posterior aplicació d'aquests elèctrodes en processos electroquímics d'oxidació avançada. Inicialment, es van considerar diferents temperatures de sinterització (entre 1050°C i 1250°C) i es va observar que un augment en la temperatura de sinterització afavoria la deposició de Sb2O3 en la superfície anòdica, disminuint així la resistivitat de l'elèctrode. Posteriorment, es va estudiar el comportament electroquímic d'aquests nous elèctrodes obtenint el potencial de descàrrega de l'oxigen mitjançant la tècnica de voltametria de passada lineal. Els resultats obtinguts van revelar que el valor del potencial de descàrrega de l'oxigen disminueix amb l'augment de la temperatura de sinterització. A més, aquests elèctrodes ceràmics van presentar un comportament intermedi entre l'ànode de Pt y l'ànode de BDD. Aquest últim elèctrode s'utilitza habitualment en els processos electroquímics d'oxidació avançada a causa de la seua elevada capacitat per a generar radicals hidroxil, els quals són capaços d'oxidar els compostos orgànics a diòxid de carboni i aigua. A continuació, es van dur a terme assajos d'oxidació electroquímica amb aquests elèctrodes ceràmics per a seleccionar la temperatura de sinterització. Els resultats van mostrar que amb l'elèctrode ceràmic sinteritzat a 1250°C s'aconsegueix una menor degradació del compost orgànic, mentre que els elèctrodes sinteritzats a menors temperatures presenten un comportament similar entre ells. Per tant, es va seleccionar l'elèctrode ceràmic sinteritzat a 1200 °C ja que presenta una baixa resistivitat i un bon comportament electroquímic per a ser utilitzat com a ànode en els processos electroquímics d'oxidació avançada. Seguidament, es va analitzar la vida útil d'aquests elèctrodes ceràmics, i es va comprovar que la matriu ceràmica incrementa en gran mesura l'estabilitat a la polarització anòdica dels elèctrodes basats en SnO2. Posteriorment es van dur a terme processos d'electro-oxidació en mode galvanostàtic de diferents contaminants difícils d'eliminar per les tècniques convencionals utilitzant com a ànode els nous elèctrodes ceràmics i l'elèctrode de BDD, per a així poder comparar els resultats obtinguts. Es va observar que, encara que amb els elèctrodes ceràmics s'aconsegueix degradar el 100% dels diferents contaminants, l'elèctrode de BDD és el més eficient ja que genera una major quantitat d'espècies oxidants actives en la seua superfície. Per a un mateix elèctrode, es va observar que un augment en la densitat de corrent aplicada millora la velocitat de degradació i mineralització de cada contaminant, mentre que l'eficiència elèctrica disminueix. D'altra banda, es va estudiar l'efecte de la presència d'una membrana d'intercanvi catiònic entre ànode i càtode. Els resultats van mostrar que l'ús de la membrana beneficia la degradació i la mineralització del contaminant, ja que millora la cinètica de reacció anòdica i evita la reducció de les espècies oxidants electrogenerades. A continuació, es va analitzar la influència de la concentració del Na2SO4 com a electròlit suport. En aquest estudi es va observar que un augment en la concentració del Na2SO4 millora la mineralització del contaminant per a l'elèctrode de BDD i, per contra, empitjora per a l'elèctrode ceràmic. Això es deu a la capacitat de cada elèctrode per a oxidar els sulfats a persulfats. Finalment, es van dur a terme assajos d'ecotoxicitat de les mostres tractades, i es va demostrar que, en presència de membrana, a major densitat de corrent i amb l'elèctrode de BDD la toxicitat de la mostra és major a causa de la major presència en dissolució d'ions persulfat. Per tant, amb l'elèctrode ceràmic, a més d'aconseguir un elevat grau de degradació del con
[EN] The present Doctoral Thesis focuses on the study of the electrochemical behaviour of new ceramic electrodes based on SnO2 doped with Sb2O3. The study is oriented at the subsequent application of these electrodes in electrochemical advanced oxidation processes. Initially, different sintering temperatures were considered (between 1050°C and 1250°C) and it was observed that an increase in the sintering temperature favoured the deposition of Sb2O3 on the anodic surface, thus decreasing the resistivity of the electrode. Later, the electrochemical behaviour of these new electrodes was studied by means of the oxygen discharge potential using the linear sweep voltammetry technique. The results obtained revealed that the value of the oxygen discharge potential decreases with increasing the sintering temperature. Furthermore, these electrodes showed an intermediate behaviour between the Pt anode and the BDD one. This last electrode is commonly used in advanced electrochemical oxidation processes due to its high capacity to generate hydroxyl radicals, which are capable of oxidizing the organic compounds to carbon dioxide and water. Then, electrochemical oxidation tests were carried out with these ceramic electrodes to select the sintering temperature. The results showed that with the ceramic electrode sintered at 1250°C, a lower degradation and mineralization of the organic compound is achieved, while the electrodes sintered at lower temperatures showed a similar behaviour. Therefore, the ceramic electrode sintered at 1200°C was selected as it presents low resistivity good electrochemical behaviour to be used as anode in electrochemical advanced oxidation processes. Next, the service life of these ceramic electrodes was analyzed, and it was found that the ceramic matrix greatly increases the anodic polarization stability of the electrodes based on SnO2. Subsequently, electro-oxidation processes were carried out in galvanostatic mode for different contaminants that are difficult to remove by conventional techniques, using the new ceramic electrodes and the BDD electrode as anodes, in order to compare the results obtained. It was observed that ceramic electrodes can be used as anodes for electrochemical oxidation, since for high current densities it is possible to degrade a 100% of the different contaminants. However, the BDD electrode is the most efficient one since it generates more active oxidant species on its surface. For a given electrode, an increase in the current density improves the degradation and mineralization of each contaminant, while the electrical efficiency decreases. On the other hand, the effect of the presence of a cation-exchange membrane between anode and cathode was studied. The results showed that its use benefits the degradation and mineralization of the contaminants, since it improves the kinetics of the anodic reaction and avoids the reduction of the electrogenated oxidant species. Next, the influence of the concentration of Na2SO4 as supporting electrolyte was analyzed. In this study it was observed that an increase in the Na2SO4 concentration improves the mineralization of the contaminant for the BDD electrode and, on the contrary, worsens for the ceramic electrode. This is due to the ability of each electrode to oxidize sulfates to persulfates. Finally, ecotoxicity tests on the treated samples were carried out, and it was shown that, in the presence of the membrane, at higher current density and with the BDD electrode, the toxicity of the sample is greater due to the higher presence of persulfate ions. Therefore, with the ceramic electrode, in addition to achieving a high degree of contaminant degradation, the treated samples are less toxic than the samples treated with the BDD electrode.
Agradezco al Ministerio de Economía y Competitividad por la financiación recibida mediante los proyectos CTQ2015-65202-C2-1-R y RTI2018-101341-B-C21, y a la cofinanciación con los fondos FEDER, que han permitido llevar a cabo la investigación en la Universitat Politècnica de València para la realización de la presente Tesis. También agradecer a Sergio Mestre Beltrán por proporcionarnos los nuevos electrodos cerámicos en los que se ha basado este trabajo.
Mora Gómez, J. (2020). Eliminación de contaminantes orgánicos emergentes mediante procesos electroquímicos de oxidación avanzada [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/158751
TESIS
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