Дисертації: "Contaminant of emerging concern"

1

Hernandez, Ruiz Selene. "Elucidation of Dissolved Organic Matter Interactions with Model Contaminants of Emerging Concern." Diss., The University of Arizona, 2011. http://hdl.handle.net/10150/145461.

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This study examined the interaction of model cationic, neutral and anionic endocrine disrupting compounds, pharmaceuticals and personal care products (EDC/PPCPs) with bulk and fractionated freshwater and waste water dissolved organic matter (DOM). The chemical composition of the freshwater DOM (Suwannee River, GA, SROM) proved to be rich in plant-derived hydrophobic aromatics, while the wastewater DOM (WWOM) contained a greater proportion of microbial biomolecular products, presumably resulting mainly from human waste. Studies focused on the fluorescence quenching of excitation-emission matrices (EEMs) of WWOM indicated that interaction with bis-phenol A (BPA), carbamazepine (CBZ), and ibuprofen (IBU) occurred preferentially with soluble protein-like and fulvic acid-like constituents. However, upon introduction to bulk SROM, BPA and CBZ were observed to quench humic acid-like regions of the EEMs, while negatively charged ibuprofen preferentially quenched the protein-like and fulvic acid components irrespective of DOM source and/or fraction. Despite this evidence of EDC/PPCP interactions with both DOM types, the strength of bonds formed was generally not sufficient to preclude full recovery and quantification of all three contaminants by liquid chromatography tandem mass spectrometry (LC-MSMS). An important exception, however, was for the hydrophilic acid fraction (HiA) of both DOM types, whose apparent bonding to cationic CBZ and anionic IBU significantly diminished LC-MSMS recovery. Thus, water sources rich in HiA character might produce a concentration underestimation of ionized EDC/PPCPs even with the use of sophisticated instruments such as LC-MSMS.The results of this research are consistent with the evolving ""supramolecular"" theory of natural organic matter, which postulates that organic matter itself is comprised of fragments of partially degraded biomolecules that are aggregated into ""supramolecular"" structures of apparent higher molar mass via relatively weak electrostatic, hydrophobic, and van der Waals interaction. Our findings suggest that EDC/PPCP contaminants, which comprise many of the same functional groups as waste water and freshwater DOM, may be incorporated into such DOM supramolecular structures, likely via the same types of intermolecular bonding, when they are present in natural waters under environmentally-relevant conditions.

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2

Ma, Yanjun. "Fate and Impacts of Contaminants of Emerging Concern during Wastewater Treatment." Diss., Virginia Tech, 2014. http://hdl.handle.net/10919/56633.

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The purpose of this dissertation was to broadly investigate the fate of antibiotic resistance genes (ARGs) and engineered nanomaterials (ENMs) as representative contaminants of emerging concern in wastewater treatment plants (WWTPs). WWTPs may have their performance impacted by ENMs and may also serve as a reservoir and point of release for both ENMs and ARGs into the environment. Of interest were potential adverse effects of ENMs, such as stimulation of antibiotic resistance in the WWTP, toxicity to microbial communities critical for WWTP performance, and toxicity to humans who may be exposed to effluents or aerosols containing ENMs and their transformation products. Response of nine representative ARGs encoding resistance to sulfonamide, erythromycin and tetracycline to various lab-scale sludge digestion processes were examined, and factors that drove the response of ARGs were discussed. Mesophilic anaerobic digestion significantly reduced sulI, sulII, tet(C), tet(G), and tet(X) with longer solids retention time (SRT) exhibiting a greater extent of removal. Thermophilic anaerobic digesters performed similarly to each other and provided more effective reduction of erm(B), erm(F), tet(O), and tet(W) compared to mesophilic digestion. Thermal hydrolysis pretreatment drastically reduced all ARGs, but they generally rebounded during subsequent anaerobic and aerobic digestion treatments. Bacterial community composition of the sludge digestion process, as controlled by the physical operating characteristics, was indicated to drive the distribution of ARGs present in the produced biosolids, more so than the influent ARG composition. Effects of silver (nanoAg), zero-valent iron (NZVI), titanium dioxide (nanoTiO2) and cerium dioxide (nanoCeO2) nanomaterials on nitrification function and microbial communities were examined in duplicate lab-scale nitrifying sequencing batch reactors (SBRs), relative to control SBRs received no materials or ionic/bulk analogs. Nitrification function was only inhibited by high load of 20 mg/L Ag+, but not by other nanomaterials or analogs. However, decrease of nitrifier gene abundances and distinct microbial communities were observed in SBRs receiving nanoAg, Ag+, nanoCeO2, and bulkCeO2. There was no apparent effect of nanoTiO2 or NZVI on nitrification, nitrifier gene abundances, or microbial community structure. A large portion of nanoAg remained dispersed in activated sludge and formed Ag-S complexes, while NZVI, nanoTiO2 and nanoCeO2 were mostly aggregated and chemically unmodified. Thus, the nanomaterials appeared to be generally stable in the activated sludge, which may limit their effect on nitrification function or microbial community structure. Considering an aerosol exposure scenario, cytotoxicity and genotoxicity of aqueous effluent and biosolids from SBRs dosed with nanoAg, NZVI, nanoTiO2 and nanoCeO2 to A549 human lung epithelial cells were examined, and the effects were compared relative to outputs from SBRs dosed with ionic/bulk analogs and undosed SBRs, as well as pristine ENMs. Although the pristine nanomaterials showed varying extents of cytotoxicity to A549 cells, and gentoxicity was observed for nanoAg, no significant cytotoxic or genotoxic effects of the SBR effluents or biosolids containing nanomaterials were observed. Studies presented in this dissertation provided new insights in the fate of ARGs in various sludge digestion processes and ENMs in nitrifying activated sludge system in lab-scale reactors. The study also yielded toxicity data of ENMs to biological wastewater treatment microbial communities and human lung cells indicated by a variety of toxicity markers. The results will aid in identifying appropriate management technologies for sludge containing ARGs and will inform microbial and human toxicity assessments of ENMs entering WWTPs.
Ph. D.

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3

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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4

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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5

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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6

Hamnca, Siyabulela. "Nanostructured polyamic acid electrocatalysts for reliable analytical reporting of sulphonamides as contaminants of emerging concern." University of the Western Cape, 2019. http://hdl.handle.net/11394/7014.

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Philosophiae Doctor - PhD
Polyamic acid (PAA) nanostructured materials were successfully produced by electrochemical deposition and electrospinning using polyvinlypyrrolidone (PVP) as supporting polymer. Polyamic acid thin film and nanofibers were deposited directly at the surface of a screen-printed carbon electrode (SPCE) as electro-catalysts for reliable analytical reporting of sulphonamide as contaminants of emerging concern by electrochemical techniques. Fourier transform infrared (FTIR) spectroscopy was used to confirm the structural integrity of the PAA electrospun nanofibers compared to the chemical synthesized PAA. Brunauer-Emmett-Teller (BET) was used to determine the surface area of the nanofibers. The surface morphology and surface thickness of the polyamic acid (PAA) nanofibers on the screen-printed electrodes was studied using scanning electron microscopy (SEM) and atomic force microscopy (AFM). Cyclic voltammetry (CV) was used to study redox behavior of the nanostructured PAA modified screen-printed carbon electrodes. Electrochemical parameters surface concentration, diffusion coefficient, formal potential and peak separation were determined. Three sulphonamides were selected based on the United States of protection agency (US EPA) and World Health Organization (WHO) list of emerging contaminants and detected sulphonamides in environmental waters in South Africa and other African regions. The selected sulfonamides were evaluated at the unmodified and modified screen-printed carbon electrodes. The sulphonamides were evaluated in three different supporting electrolytes at pH < 7 and >7 to enhance electrochemical signal reporting. Sulfadiazine (SDZ), sulfamethoxazole (SMX) and sulfamethazine (SMZ) displayed peaks at 0.80 V vs Ag/AgCl in 0.1 M tris-HCl using square wave voltammetry at the unmodified transducer. At the PAA thin film transducer, SDZ, SMX and SMZ displayed well-defined analytical oxidative peaks at 0.77 V 0.82 V and 0.83 V vs Ag/AgCl respectively. The LOD (n=3) for SDZ was found to be 12.14 ųM with a correlation coefficient of 0.9950. The LOD (n=3) for SMX and SMZ was found to 14.59 ųM (R2 =0.9928) and 10.41 ųM (R2 =0.9963). These sulphonamides were also electro-analytical evaluated at the screen-printed carbon PAA nanofiber modified transducer. SDZ, SMX and SMZ produced well-defined analytical signals at 0.79 V, 0.81 V and 0.78 V vs Ag/AgCl respectively. The determined LOD (n=3) for the individual sulphonamides was 8.26 ųM, 16.59 ųM and 8.81 ųM SDZ, SMX and SMZ respectively. The linearity correlation coefficient (R2) was determined to be 0.9977, 0.9956 and 0.9974 respectively. The efficacy of the proposed nanostructured PAA thin film modified screen-printed carbon sensor was evaluated by performing recovery studies for the selected sulphonamides using square wave voltammetry. Tap water was used to simulate environmental matrix. The recoveries of SDZ with respect to each concentration were 98.84% (RSD 4.98%) to 40.58% (RSD 6.74%). For SMX the recoveries were 154.17% (RSD 11.00%) to 111.03% (RSD 16.80%). The recoveries for SMZ with respect to each concentration were 184% (RSD 8.19%) to 90.26 (RSD 18.26%) indicating the reliability of the analytical results.
2021-09-01

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7

Platten, William E. III. "Fate of Emerging Contaminants in Biomass Concentrating Reactors (BCR) under Conventional Aerobic and Aerobic/Anoxic Treatment." University of Cincinnati / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1406881476.

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8

Ojemaye, Cecilia Yejide. "Identification and quantification of chemicals of emerging concern (persistent organic and inorganic pollutants) in some selected marine environments of cape town, South Africa." University of the Western Cape, 2020. http://hdl.handle.net/11394/7877.

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Philosophiae Doctor - PhD
The increasing evidence of chemicals of emerging concern (CECs) in water bodies is causing major concern around the world because of their toxicological effects upon humans and aquatic organisms. 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. These compounds are often persistent but not regularly monitored because they are mostly still excluded from environmental legislation. Their fate and persistence in the environment are not well understood.
2022-02-24

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9

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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10

Cullin, Joseph Albert. "Reach-scale predictions of the fate and transport of contaminants of emerging concern at Fourmile Creek in Ankeny, Iowa." Thesis, The University of Iowa, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=1560631.

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Contaminants of emerging concern (CECs) are an unregulated suite of constituents frequently detected in environmental waters, which possess the potential to cause a host of reproductive and developmental problems in humans and wildlife. Degradation pathways of several CECs are well-characterized in idealized laboratory settings, but CEC fate and transport in complex field settings is poorly understood. In the present study I use a multi-tracer solute injection to study and quantify physical transport and photodegradation in a wastewater effluent-impacted stream in Ankeny, Iowa. Conservative tracers are used to quantify physical transport processes in the stream. Use of reactive fluorescent tracers allows for isolation of the relative contribution of photodegradation within the system. Field data were used to calibrate a one-dimensional transport model, and forward modeling was then used to predict the transport of sulfamethoxazole, an antibiotic in the effluent which is susceptible to photolysis. Results show that accurate predictions of reactive CECs at the scale of stream reaches can be made using the fate and transport model based on field tracer studies. Results of this study demonstrate a framework that can be used to couple field tracer and laboratory CEC studies to accurately predict the transport and fate of CECs in streams.

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11

Thomas, Kevin Victor. "Understand the environmental fate, behaviour, effects and risks associated with contaminants of emerging concern (CECs) with the goal of protecting environmental and human health." Thesis, University of Plymouth, 2016. http://hdl.handle.net/10026.1/6515.

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Each and every one of us is exposed to chemicals on a daily basis and contributes to the global issue of chemical pollution. Humankind has become heavily dependent on the use of man-made chemicals in order to sustain the increased quality of life that is generally seen globally. There is however a price to pay in that we generally live in a world that is polluted by anthropogenic chemicals. From the water we drink to the food we eat there will be some trace of chemical residues; you just need to look closely enough and/or know what you’re looking for. With many hundreds of thousands of man-made chemicals approved within Europe for use in various ways, it is no surprise that we come into daily contact with them. What is also important to understand is that the presence of a man-made chemical is not enough to establish whether it poses a risk to environmental or human health; it needs to be present in sufficient amounts to elicit an effect. Over the past 20 years the focus of my research been on understanding which chemicals we should be concerned with, which pose the greatest risk and why do they pose such a risk. This work is of major societal and scientific significance as it protects the world we live in whilst teaching us about the better regulation of the chemicals we have become so dependent. To understand the nature of my research it is important to understand that prior to the mid-nineteen nineties hazardous organic chemicals were typically restricted to lists comprising of a number of banned (and typically chlorinated) pesticides, polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans and the antifouling biocide tributyltin (TBT). One of the major enigmas that faced environmental scientists at the time was that even though it was possible to quantify and monitor the presence of the above hazardous substances in the environment, they often didn´t explain the environmental quality measured though biological effects on organisms. Chemicals are globally regulated on an individual substance level and subsequently within the context of influencing these regulations, for the improved protection of environmental and human health, it is therefore essential to know which chemical contaminants are actually causing biological effects. It is also necessary to know the levels at which any organism will be exposed and what the consequences of these levels. My research subsequently became focused on two separate approaches; identifying which substances actually cause the biological effects unexplained by hazardous substances and evaluating the occurrence, environmental fate and ecotoxicity of those chemicals not routinely monitored or present on priority lists of hazardous substances; a group of chemical contaminants later termed contaminants of emerging concern (CECs). An effect-directed non-target approach A targeted approach to environmental analysis infers that we know exactly what we should be looking for. Whilst this is a suitable approach for chemicals that we suspect may be of concern, it does not help us understand which other contaminants may be present in the environment and potentially causing harm. When embryos of oysters exposed to estuarine surface waters developed deformities and this could not be attributable to the levels of priority hazardous substances a bioassay-directed non-target approach to environmental analysis was developed to identify chlorinated and alkylphenols as responsible [5, 6]. This approach has subsequently evolved into the approach termed effect-directed analysis (EDA) and is widely used globally for the identification of CECs. My own research has successfully applied the approach to identify for the first time a number of important environmental contaminants; steroidal androgens [10, 13, 14] as environmental contaminants, the phthalate ester bis(2-ethylhexyl)phthalate [10], cinnarizine, cholesta-4,6.dien-3-one [19], C1-C5 and C9 alkylphenols [21], petrogenic naphthenic acids [57] as environmental estrogen receptor agonists, C1-C5 and C9 alkylphenols [21], PAHs and petrogenic naphthenic acids [57] as androgen receptor antagonists and unresolved polar aromatic compounds as important environmental genotoxins [15]. Another focus of my effects-directed research has been identifying environmental contaminants that exert the same effects as dibenzo-p-dioxins and polychlorinated dibenzofurans in that they are aryl hydrocarbon receptor (AhR) agonists. Dioxin-like chemicals are ubiquitous in the environment and in addition to those that are routinely monitored there are a large number of other compounds that exert dioxin-like effects [26, 28, 32, 33, 37, 52, 64, 82, 93, 98, 99]. Better understanding of AhR agonists will in the long run help protect the environment and humans from a particularly hazardous group of chemicals. A targeted approach The early- to mid-nineteen nineties saw the widespread introduction of liquid chromatography coupled to mass spectrometry (LC-MS) to the environmental analytical toolbox. Robust instruments typically using electrospray and atmospheric pressure chemical ionisation were well suited to the analysis of the more polar CECs, such as alternative antifouling biocides to TBT, pharmaceuticals, personal care products, veterinary medicines, illicit drugs and rodenticides. Robust analytical methodology is key to my research [2, 4, 18, 31, 34, 35, 42, 49, 66, 69, 72, 73, 86, 94, 102] as it allows the better understanding of how contaminants behave and interact with the environment. Development of robust, specific and sensitive methods for the analysis of alternative antifouling biocides [2, 4] allowed for the first time an evaluation of their life-cycle from release at the paint surface, and the factors that influence this [3], their occurrence in the environment [7, 8, 12, 29], fate and behaviour [12, 16] and subsequent effects [36, 41]. Assessment of the environmental risks based upon these data showed that both Irgarol 1051 and diuron were a threat to freshwater and marine algae. The significance of this research is that it subsequently led to restrictions being placed on the use of Irgarol 1051 and diuron in antifouling products in a number of European countries [58] and an awareness of the hazards associated with the deliberate release of biocidal products into the environment [86]. Observations of human pharmaceutical residues in the chromatograms of wastewater effluent samples being analysed by EDA and reports of their occurrence in German wastewaters motivated the development of LC- tandem MS methods for the quantification of pharmaceutical residues in waste- and surface waters [18]. Pharmaceuticals, we showed, occur in treated wastewater effluents and marine and freshwater recipients [24, 25, 30, 42, 43, 51, 66] and that, to no great surprise, the per capita pharmaceutical loads from hospitals were greater than the general population [43, 51]. Other highlights include understanding the processes that occur within sewer systems and what influences pharmaceutical occurrence in the final treated effluent [59, 60, 81, 85, 105], all of which allow for a better assessment of the overall risk posed to the environment. Even though several hundred papers have been published on pharmaceuticals in the environment since my early work, this has almost exclusively been focused on the parent pharmaceutical ingredient in aqueous matrices from developed counties. To remedy this shortfall more recent work has focused on quantifying the proportion of pharmaceutical metabolites released as compared to the parent [66], pharmaceutical occurrence in sludges and sediments [69], as well as evaluating occurrence in less studied water cycles [101].

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12

Laczko, Stephen M. "Evaluation of the Thyroid Endocrine System in Two Flatfish Species in Relation to Exposures to Legacy Contaminants and Contaminants of Emerging Concern." Thesis, California State University, Long Beach, 2018. http://pqdtopen.proquest.com/#viewpdf?dispub=10826608.

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Anthropogenic contaminants have been well documented in Southern California coastal marine waters and are largely associated with point source pollution entities like waste water treatment plants (WWTPs). This study measured known and suspected contaminants capable of disrupting physiological and endocrine functions in marine organisms. Thyroid endocrine and hepatic contaminant concentrations were measured in English Sole (Parophrys vetulus) and Hornyhead Turbot (Pleuronichthys verticalis) residing at a WWTP outfall location and two other locations, up- and down-current from the outfall. Fish from the outfall and down current locations had higher levels of contaminant compounds and altered thyroid endocrine physiology compared to the up-current reference location. Selected contaminants were significantly correlated with thyroid endocrine parameters, consistent with observed differences in contaminant levels among sites.

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13

Batchu, Sudha Rani. "Photo Degradation of Cotnaminants of Emerging concern (CECs) under Simulated Solar Radiation: Implications for their Environmental Fate." FIU Digital Commons, 2013. http://digitalcommons.fiu.edu/etd/859.

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Contaminants of emerging concern (CECs) are continuously being released into the environment mainly because of their incomplete removal in the sewage treatment plants (STPs). The CECs selected for the study include antibiotics (macrolides, sulfonamides and ciprofloxacin), sucralose (an artificial sweetener) and dioctyl sulfosuccinate (DOSS, chemical dispersant used in the Deepwater Horizon oil spill). After being discharged into waterways from STPs, photo degradation is a key factor in dictating the environmental fate of antibiotics and sucralose. Photodegradation efficiency depends on many factors such as pH of the matrix, matrix composition, light source and structure of the molecule. These factors exert either synergistic or antagonistic effects in the environment and thus experiments with isolated factors may not yield the same results as the natural environmental processes. Hence in the current study photodegradation of 13 CECs (antibiotics, sucralose and dicotyl sulfosuccinate) were evaluated using natural water matrices with varying composition (deionized water, fresh water and salt water) as well as radiation of different wavelengths (254 nm, 350 nm and simulated solar radiation) in order to mimic natural processes. As expected the contribution of each factor on the overall rate of photodegradation is contaminant specific, for example under similar conditions, the rate in natural waters compared to pure water was enhanced for antibiotics (2-11 fold), significantly reduced for sucralose (no degradation seen in natural waters) and similar in both media for DOSS. In general, it was observed that the studied compounds degraded faster at 254 nm, while when using a simulated sunlight radiation the rate of photolysis of DOSS increased and the rates for antibiotics decreased in comparison to the 350 nm radiation. The photo stability of the studied CECs followed the order sucralose > DOSS > macrolides > sulfonamides > ciprofloxacin and a positive relationship was observed between photo stability and their ubiquitous presence in natural aquatic matrices. An online LC-MS/MS method was developed and validated for sucralose and further applied to reclaimed waters (n =56) and drinking waters (n = 43) from South Florida. Sucralose was detected in reclaimed waters with concentrations reaching up to 18 µg/L. High frequency of detection (> 80%) in drinking waters indicate contamination of ground waters in South Florida by anthropogenic activity.

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14

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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15

Schmidt, Natascha. "Environmental occurrence and fluxes of organic contaminants of emerging concern in the coastal NW Mediterranean sea and the Rhône river." Electronic Thesis or Diss., Aix-Marseille, 2019. http://www.theses.fr/2019AIXM0270.

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Les contaminants organiques d'intérêt émergent, tels que les phtalates (PAEs), les esters organophosphorés (OPEs), les bisphénols (BPs), les composés perfluorés (PFCs) et les microplastiques (MPs) sont aujourd'hui largement diffusés dans les milieux aquatiques. Leur présence dans la baie de Marseille, le Rhône et l'Atlantique Nord tropical est examinée dans cette étude. Il est démontré que le Rhône est une source d'apports de MPs et d'additifs plastiques dans le Golfe du Lion (Méditerranée NO) et que les intrusions de ses eaux sont suffisantes pour atteindre des concentrations de PFCs dépassant la norme annuelle moyenne de qualité environnementale dans la baie de Marseille. A Marseille, le zooplancton présent des concentrations de PAEs particulièrement élevées, ce qui soulève des questions sur les conséquences pour le réseau alimentaire marin et les ressources locales. Enfin, la possibilité d'un transport d’OPEs à longue distance est examinée à l'échelle de l'Atlantique Nord tropical
Organic contaminants of emerging concern, such as phthalates (PAEs), organophosphate esters (OPEs), bisphenols (BPs), perfluorinated compounds (PFCs) and microplastics (MPs) are nowadays widely distributed in aquatic environments. Their occurrence in the Bay of Marseille, the Rhône River and the tropical North Atlantic was investigated in this study. The Rhône River is shown to be a source of MP and plastic additive inputs to the Gulf of Lions (NW Mediterranean Sea) and intrusions of its waters are shown to be enough to attain PFC concentrations exceeding the annual average Environmental Quality Standard in the Bay of Marseille. In the Bay of Marseille, zooplankton samples exhibit particularly high PAE concentrations, raising questions concerning the consequences for the marine food web and local marine resources. Finally, the possibility of long-range OPE transport is examined at the scale of the tropical North Atlantic

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16

Hachgenei, Nico. "Transfert d'eau et de résidus pharmaceutiques vétérinaires dans un bassin versant agricole de méso-échelle soumis aux crues éclairs." Thesis, Université Grenoble Alpes, 2022. http://www.theses.fr/2022GRALU007.

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Ce travail se concentre sur le transfert environnemental des résidus de médicaments vétérinaires qui pénètrent dans l'environnement via les excréments des animaux traités. Il est étudié dans les conditions d'un bassin versant à méso-échelle sous climat méditerranéen avec une agriculture extensive.Dans un premier temps, lors d’entretiens avec des éleveurs 14 composés pharmaceutiquement actifs (PhAC) ont été identifiés comme étant systématiquement utilisés dans le bassin versant, dont 10 antiparasitaires. Les antibiotiques n'étaient utilisés de manière significative que pour les chèvres. Nous avons choisi l'Ivermectine (IVM) comme molécule représentative de ces médicaments antiparasitaires et nous avons fait des expériences de transfert sur ce composé.Pour ces expériences, nous avons mis au point un dispositif permettant de prélever des monolithes de sol intacts et de les soumettre à des pluies simulées. Des bouses de vaches non traitées ont été dopées à une concentration réaliste telle que rapportée dans la littérature et placées sur le sol. Des événements pluvieux intenses consécutifs ont été simulés et le ruissellement de surface (OF) ainsi que le flux de drainage ont été mesurés et échantillonnés à haute fréquence. Des valeurs de concentration allant jusqu'à 3855 ng L-1 ont été observées dans l'OF. La concentration dans le flux de drainage était significativement réduite dans les sols provenant de la de la partie sédimentaire du site d'étude 150 ng L-1. Sur les sols du plateau basaltique du Coiron, l'hydrophobicité du sol a conduit à un fort écoulement préférentiel et la concentration d'IVM n'a pas été substantiellement réduite au passage à travers le sol. D'un autre côté, une humidité initiale du sol plus élevée a conduit à une rétention accrue de l'IVM à la fois par le drainage et par l'OF. En général, plus d'OF et une plus grande exportation d'IVM ont été observées sur les sols du plateau du Coiron. A cette échelle, l'hydrophobicité du sol semble jouer un rôle important dans la génération de l'OF.Enfin, afin de relier ces résultats à l'échelle du bassin versant et à la problématique globale de transfert des résidus pharmaceutiques vers les masses d'eau de surface, un modèle hydrologique conceptuel semi-distribué a été développé à l'échelle du bassin versant de la Claduègne afin d'estimer les distributions de temps de transit (TTD) sur un pas de temps horaire à l'aide de fonctions SAS et de suivi d'âge. Le modèle a été calibré par rapport au débit observé, à la concentration en silice et au rapport isotopique en deutérium de la molécule d'eau à l'exutoire. Le modèle prédit des fractions allant jusqu'à 60 % du débit à l'exutoire d'un âge inférieur à un jour pendant les événements de crue majeurs. Sur l'ensemble de la période d'observation, cette fraction représente 8.4 % de l'écoulement total. En moyenne, 25 % du volume d'eau sortant du bassin versant a un âge inférieur à 30 jours.L'analyse de quelques échantillons d'eau de ruisseau de la Claduègne pour trois produits pharmaceutiques vétérinaires a révélé que le Fenbendazole (FBZ) et le Mebendazole (MBZ) étaient présents à des concentrations détectables uniquement en période de crue, ce qui indique une forte importance de l'écoulement préférentiel pour leur transfert dans les ruisseaux. Des concentrations de l'antiparasite porcin FBZ allant jusqu'à 28.5 ng L-1 ont été observées lors d'un petit événement de crue en été, ce qui correspond à 355 fois la concentration prédite sans effet (PNEC) pour les poissons
This work focuses on environmental transfer of residues of veterinary drugs entering the environment via dung from treated animals. It is studied under the conditions of a meso-scale catchment under Mediterranean climate with extensive agriculture.In a first step, interviews with livestock breeders were conducted to identify the treatment practices. 14 pharmaceutically active compounds (PhAC) were identified to be systematically used in the catchment, 10 of which antiparasitic drugs. Antibiotics were of significant use only for goats. We chose Ivermectin (IVM) as a representative molecule for those antiparasitic drugs and did further transfer experiments on this compound.For these experiments, we developed a device to sample intact soil monoliths and subject them to simulated rainfall. Dung from untreated cows was spiked to a realistic concentration (3 mg kg−1) as reported in literature and placed on the soil. Consecutive intense rain events were simulated and surface runoff and drainage flow were measured and sampled at high frequency. Concentration values of up to 3855 ng L−1 were observed in overland flow (OF). The concentration in drainage flow was significantly reduced in soils from the sedimentary foothills part of the study site (< 150 ng L−1). On soils from the Coiron basaltic plateau, water repellency led to strong preferential flow and the concentration of IVM was not substantially reduced by leaching through the soil. Higher initial soil moisture led to increased retention of IVM through both drainage and OF. Overall, up to 1 % of the initial mass of IVM was exported during two consecutive rain events. In addition, we could show that drying of cow dung effectively reduces the mobilization of IVM. In general, more OF and a higher export of IVM were observed on soils from the Coiron plateau. On this scale, soil water repellency (SWR) seems to play a substantial role in the generation of OF.Finally, in order to link those results to the catchment scale and the overall problematic of transfer of pharmaceutical residues to surface water bodies, a semi-distributed conceptual hydrological model was developed on the scale of the Claduègne catchment using SAS functions and age tracking in order to estimate transit time distributions (TTD) on an hourly time step. The model was calibrated against observed discharge, silica concentration and deuterium isotope ratio of the water molecule at the outlet. The model predicts fractions of up to 60 % of discharge at the outlet of an age below one day during major flood events. Over the whole observation period, this fraction represents 8.4 % of the total runoff. In average, 25 % of the discharge are less than 30 d old.The analysis of a few stream water samples from the Claduègne catchment for three veterinary pharmaceuticals revealed that Fenbendazole (FBZ) and Mebendazole (MBZ) were only present at detectable concentrations throughout flood events, indicating a strong importance of preferential flow for their transfer into the streams. Concentrations of the pork antiparasitic FBZ of up to 28.4 ng L-1 were observed during a small flood event in summer, which is 355 time the predicted no effect concentration (PNEC) for fish.This thesis shows that high amounts of IVM can be mobilized from cow dung and transferred through and over soil at the plot-scale, despite the fact that IVM is generally considered immobile due to its hydrophobicity and therefore strong adsorption to the soil's organic matter. The highest mobilization of IVM was observed under the condition of intense precipitation on dry soil due to water repellency causing strong preferential flow (including OF). Preliminary results on the catchment scale suggest that this mechanism may as well be effective on this scale, despite the smaller amplitude of the hydrological response. An age tracking model reveals a high fraction of event water in the discharge at the Claduègne outlet during major flood events

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17

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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18

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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19

Huang, Ying. "Applications of UV/H2O2, UV/NO3–, and UV-vis/ferrite/sulfite Advanced Oxidation Processes to Remove Contaminants of Emerging Concern for Wastewater Treatment." University of Cincinnati / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1535703890003601.

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20

Hurtado, Cervera Carlos. "Fate and effects of waterborne contaminants of emerging concern in the soil-plant system : impact of biochar soil amendment to mitigate their plant uptake." Doctoral thesis, Universitat Politècnica de Catalunya, 2017. http://hdl.handle.net/10803/458444.

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Water scarcity is an issue of global concern due to the increase of the population and the climate change, which both increase the water demand. Many arid and semiarid countries are facing high water stress and the use of reclaimed water becomes a valuable resource. Many countries' economy is based on the agro-food sector, with amounts ca. the 70% of water demand. For this reason, reclaimed water represents an important component of wise water management. Wastewater treatment plants (WWTP) are designed to remove efficiently some biodegradable compounds, however, they are not able to remove a number of recalcitrant organic coñtamina0nts known as chemical oxygen demand (COD). There are many sources of water pollution, and contaminants of emerging concern (CECs) including many compounds that they are not legislated and recently some effects to the environment have been observed. For example, pharmaceuticals, personal care products, flame retardants, microplastics, etc. Consequently, plants are exposed to a huge number of chemical contaminants that are present not only in water, but also in air or soil. For this reason, it is important to understand the dynamics involved in the plant uptake of these CECs and more specifically in crops. In this Thesis, the uptake of some CECs, chosen by their occurrence in the environment and their physical-chemical properties, has been assessed. To elucidate the factors that are involved in the uptake of these contaminants, three different experiments were performed in a greenhouse. Therefore, this Thesis is divided in the three experiments. In the first one, the plant uptake of some CECs with a perlite:sand mixture and its modelling were assessed. Moreover, a mass balance was performed to evaluate the persistence of the CECs in the substrate. Then, by inverse modelling, the half-lives of CECs in the soil-plant system were estimated. In the second experiment, most of the CECs that were added in the irrigation water were taken up by lettuce. Hence, in this experiment, biochar, which is a soil improver, was assessed as a soil amendment to mitigate the uptake of these CECs in lettuce. To confirm this hypothesis, different biochar amendments were performed (O, 2.5 and 5% w/w biochar) to an agricultural soil from the Llobregat's Delta. Finally, it could be observed that the addition of biochar, reduced the concentration of CECs in lettuces. Since these two experiments demonstrated that CECs can be uptaken by crops and translocated to edible parts, and it well known that plants can metabolize xenobiotics through transformation, conjugation and sequestration steps, in the third experiment, an enzymatic digestion was performed to determine the conjugated CECs fraction. Interestingly, the conjugated fraction accounted up to more than 80%, which should be taken into account in risk assessment studies. Finally, in the same experiment, some effects of CECs to lettuce were elucidated. Visual differences between non-exposed and exposed lettuce were observed. For this reason, a metabolomic approach was applied to correlate the presence of CECs with the changes in the metabolome and the changes in chlorophyll content and plant morphology.
L'escassetat d'aigua és un tema de gran preocupació degut a l'augment de la població i el canvi climàtic, que tan que s’elevi la demanda d'aigua. Molts països amb un clima àrid o semiàrid s'enfronten a un elevat estrès hídric. En aquest context, l'ús d'aigua regenerada es converteix en una practica clau. L'economia de molts passos es basa en el sector agroalimentari, que requereix grans quantitats d'aigua pel seu desenvolupament. Per aquesta raó, l'aigua regenerada representa un component important en la gestió intel·ligent de l'aigua. Les estacions depuradores d'aigües residuals (EDAR) estan dissenyades per eliminar de manera eficient alguns compostos biodegradables. Tot i així, no són capaces d'eliminar una sèrie de contaminants orgànics. Hi ha molts tipus de contaminació en l'aigua i els contaminants emergent (CECs) inclouen molts compostos que no estan legislats i recentment s'han observat alguns efectes en el medi ambient. Alguns exemples de CECs són fàrmacs, productes de cura personal, retardants de flama, microplàstics, etc. En conseqüència, les plantes estan exposades a un gran nombre de contaminants que es troben presents no només en aigua, sinó també en l’aire o el sol. Per aquest motiu, és important entendre la dinàmica implicada en l'absorció d’aquests contaminants en plantes i cercar estratègies per mitigar aquesta possible absorció. Aquest treball de recerca té com a objectiu estudiar l'absorció de diversos CECs en enciams, que han estat seleccionats perla seva presencia en el medi ambient i les seves propietats fisicoquímiques. Per dilucidar els paràmetres que estan implicats en l’absorció d'aquests contaminants en enciams, tres experiments diferents s’han dut a terme en l’estació experimental Agròpolis pertanyent a la UPC. Per tant, aquesta Tesi es pot separar en els 3 experiments duts a terme. En el primer experiment, es va avaluar l'absorció d'alguns CECs en enciams emprant un substrat format per una mescla de sorra i perlita. L’experiment va dilucidar que la majoria deis CECs van ser absorbits pels enciams i translocats a les parts aèries deis enciams. D'altra banda, un balanç;: de masses es va realitzar per avaluar la persistència deis CECs en el substrat. Després, mitjançant models d’incorporació de contaminants en plantes, es van estimar les vides mitjanes deis CEC en el sistema sol-planta. En un següent experiment, l’ús de biocarbó (biochar) es va proposar com una esmena del sol per reduir l'absorció d'aquests CECs als enciams. Per dur confirmar aquesta hipòtesi, es van afegir diferents percentatges de biochar (O, 2,5 i 5% de biochar) en un sol agrícola de la zona agrícola del Delta del Llobregat. Finalment, es va poder observar que l’addició de biochar reduí la concentració deis CECs en els enciams. Aquests dos primers experiments van ser útils per evidenciar que aquests compostos es poden absorbir fàcilment perles plantes i arribar a les parts que comestibles. No obstant, en altres estudis s’ha demostrat que les plantes són capaços de metabolitzar xenobiòtics a través de tres passos: transformació, conjugació i segrest deis CECs. Per aquest motiu, es va realitzar una digestió enzimàtica per determinar la fracció de CECs que podrien ser conjugats. Curiosament i segons el contaminant, la fracció conjugada va representar més del 80% del compost parental, evidenciant que la fracció conjugada s'ha de tenir en compte en els estudis d'avaluació de risc humà. Finalment, en aquest mateix experiment, es varen observar diferencies morfològiques entre els enciams exposats a un còctel de CECs i els no exposats als contaminants. A més, la determinació de clorofil·les també va evidenciar diferencies entre tractaments. Per aquesta raó, es van extreure els metabòlits secundaris deis enciams emprant un enfocament metabolòmic juntament amb tècniques quimiomètriques per correlacionar la presencia d’aquests contaminants amb els canvis morfològics i en el contingut de clorofil·la i dels metabòlits secundaris

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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-TiO₂) 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 (TiO₂-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-TiO₂ 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 TiO₂. 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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22

Mézière, Marie. "Analytical strategy development for the analysis of chlorinated paraffins : Study of the fate of those contaminants of emerging concern in the laying hens and contribution of the evaluation of the human dietary exposure." Thesis, Nantes, Ecole nationale vétérinaire, 2020. http://www.theses.fr/2020ONIR146F.

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Les chloroparaffines (CP) sont des chaînes de n-alcanes polychlorées, utilisées en tant que plastifiants, retardateurs de flamme ou lubrifiants. Alors que leur ubiquité dans l’environnement a été démontrée par diverses études, l’évaluation du risque associé à l’exposition de l’homme à ces contaminants en Europe demeure très limitée. Le manque de données s’expliquant notamment par de nombreux défis analytiques, la présente thèse a été initiée pour développer une stratégie analytique innovante puis pour fournir des données nouvelles sur le comportement des CP le long de la chaîne alimentaire et sur leur prévalence dans les aliments. Une stratégie analytique basée sur un couplage LC-HRMS a d’abord été mise en place, avec une attention particulière portée à leur séparation chromatographique et à leur ionisation. La stratégie analytique finalisée, incluant une préparation d’échantillon optimisée et un traitement de données automatisé, permet d’analyser les CP de C10 à C36 à l’état de traces (ppb) dans des matrices biologiques complexes. Cette méthode a été appliquée à l’étude du comportement des CP chez la poule pondeuse en fonction de la longueur de chaîne et du degré de chloration, après exposition alimentaire. Il a pu ainsi être démontré que tous les CP sont biodisponibles. De plus, les CP ont été retrouvés dans les organes internes de la poule démontrant leur circulation dans l’organisme, à l’exception des chaînes les plus longues à taux de chlore élevé. Enfin, l’analyse d’un jeu d’aliments représentant le panier de la ménagère a permis de présenter une première évaluation de l’exposition alimentaire en France
Chlorinated paraffins (CPs) are polychlorinated n-alkane chains, used as plasticizers, flame retardants or lubricants. While their ubiquity in the environment has been evidenced in various studies, the risk assessment related to the human exposure to those contaminants in Europe remains incomplete. As the lack of data arises from many analytical challenges, this thesis was initiated to develop an innovative analytical strategy and to provide new insight on the behaviour of CPs along the food chain and their occurrence in food. An analytical strategy based on LC-HRMS coupling was first implemented, with particular attention paid to their chromatographic separation and ionization efficiency. The finalised analytical strategy, including an optimized sample preparation and automated data processing, enables trace analysis (ppb) of CPs from C10 to C36 in complex biological matrices. This method was applied to study the behaviour of CPs in the laying hen according to chain length and degree of chlorination after dietary exposure. It was thus demonstrated that all CPs are bioavailable. Moreover, the CPs were found in the internal organs of the hen demonstrating their circulation in the organism, with the exception of the longest chains with a high chlorine content. Last, the analysis of various foodstuffs representing the household basket has allowed to present a first assessment of dietary exposure in France

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23

Munoz, Gabriel. "Ecodynamique des composés poly- et perfluoroalkylés dans les écosystèmes aquatiques." Thesis, Bordeaux, 2015. http://www.theses.fr/2015BORD0414/document.

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Les tensioactifs poly- et perfluoroalkylés (PFAS) sont des composés d’origine anthropique produits à partir des années 1950 et qui sont désormais considérés comme des polluants ubiquistes. La première partie de ce travail a consisté à optimiser et valider des procédures pour l’analyse ultra-trace des PFAS. Ces méthodes ont ensuite été utilisées afin d’apporter de nouveaux éléments de réponse sur l’occurrence et la dynamique des PFAS dans les environnements aquatiques. Une attention particulière a été accordée aux valeurs censurées (
Poly- and perfluoroalkyl surfactants (PFAS) are anthropogenic compounds that have been used sincethe 1950s in a variety of applications and that have emerged as ubiquitously distributed contaminants.The first aim of this work was to optimize and validate analytical procedures for the trace-leveldetermination of PFAS. These methods were then applied to various sets of environmental samples,providing new elements to document the occurrence and environmental fate of PFAS in aquaticecosystems. In terms of statistical analyses, a special care has been devoted to incorporate nondetects(data 1 for PFOS and several long-chain PFAA, providing new evidence for theirbiomagnification. The last theme addressed in this work was the analysis of newly-identified cationicand zwitterionic PFAS ; preliminary evidence seem to dispel concerns about the bioaccumulationpotential of the latter

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24

Hobson, Chad. "Exploring tungsten in the environment: geochemical study of an emerging contaminant." Thesis, Kansas State University, 2013. http://hdl.handle.net/2097/16991.

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Master of Science
Department of Geology
Saugata Datta
Tungsten (W) has become an element of greater concern in recent years. Investigations by the Centers for Disease Control implicated W as a possible link to several cases of childhood acute lymphatic leukemia (ALL) clusters in the western United States. In Fallon NV, 17 cases of ALL were reported from 1997-2001. Previously, it was difficult to attain knowledge about the geochemical behavior of W due to low concentrations and difficulties in detection in natural environments. Modern analytical techniques allow for a greater range of sensitivity, allowing for in depth W analysis. Elucidating information on the factors contributing to the fate and transport of W in low temperature environments will provide insight into how W moves through the environment and provide information to help mitigate W contamination in the future. Three sites were chosen for comparison of W concentration and how that may be linked to local geochemical factors. Fallon NV, Sierra Vista AZ, and Cheyenne Bottoms Refuge KS were chosen based on published literature and personal communications. The objectives for this study were to characterize W concentrations in these three climatologically distinct areas followed by using methods to speciate and semi-quantitatively characterize W phase association within the surficial sediments and using synchrotron X-Ray methods to define W valencies and elemental associations within the sediments. Tungsten occurs in varying concentrations in the study areas, from 17.8 mg/kg to ~25,907 mg/kg. Fallon has the highest average W concentration of the three sites as well as the highest amount of W associated with phases other than the organic matter or residual phase. Speciation of soluble W revealed no polytungstates, however tungstates are present in the samples as well as undefined W species, suggesting there are other forms of W that are readily soluble in water, hence bioavailable. Tungsten has a very heterogeneous distribution in sediments, creating dispersed but highly concentrated clumps of W hotspots. Spot analyses under X-Ray mapping reveal W may co-localize with other metals such as Ti, Co, and Zn.

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25

Lauzent, Mathilde. "Etude de l’écodynamique des polluants organiques persistants et des micropolluants halogénés d’intérêt émergent dans les milieux aquatiques." Thesis, Bordeaux, 2017. http://www.theses.fr/2017BORD0733/document.

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Les PCB (polychlorobiphényles), PBDE (éthers de biphényles polybromés) et OCP (pesticides organochlorés) sont des composés d’origine anthropique classés comme POP (polluants organiques persistants) dont l’usage a progressivement été restreint ou interdit. Ces composés, de par leur caractère ubiquiste, persistant et bioaccumulable, sont néanmoins toujours présents dans l’environnement, d’où l’importance de continuer à étudier leur présence, leur dynamique et leur impact. Du fait de la restriction de leurs usages, d’autres composés sont maintenant utilisés pour les remplacer, tels que les retardateurs de flamme alternatifs (RFA). Ces composés bromés et chlorés ont des propriétés physico-chimiques comparables à celles des POP précités et peuvent potentiellement constituer un danger chimique pour l’environnement. Par ailleurs, les RFA sont attendus à des niveaux de concentration plus faibles que les PCB et les PBDE que ce soit dans les compartiments biotiques et abiotiques. Ainsi, l’un des enjeux de ce travail de thèse était de développer une méthode multi-résidus, associant chromatographie en phase gazeuse et spectrométrie de masse à temps de vol, permettant d’analyser simultanément 17 RFA à des niveaux inférieurs au ng.g-1. Les niveaux et profils de contamination en POP et RFA ont ensuite été renseignés dans les compartiments biotiques et abiotiques de différents systèmes aquatiques contrastés. Le caractère bioamplifiable de ces composés a été étudié grâce à la détermination de facteurs d’amplification trophique (TMF) dans l’estuaire de la Gironde et dans le bassin du Rhône, à l’aide d’outils statistiques innovants. Dans l’estuaire de la Gironde il a été mis en évidence que certains RFA étaient autant voire plus bioamplifiables que certains POP historiques. Par ailleurs, dans le bassin du Rhône, l’utilisation des TMF comme outil prédictif, pour le BDE-47 ou la ΣPBDE-DCE par exemple, a été discutée et parait envisageable dans un cadre réglementaire
PCBs (polychlorinated biphenyls), PBDEs (polybrominated biphenyl ethers) and OCPs (organochlorine pesticides) are anthropogenic compounds classified as POPs (Persistent Organic Pollutants), their use was restricted or prohibited. These compounds are ubiquitous, persistent and bioaccumulative and they are still present in the environment; this is the reason why it is important to continue the study of the fate and impact in the environment. Due to their usage restriction, other compounds are now used to replace them, such as alternative flame retardants (RFAs). These brominated and chlorinated compounds have physicochemical properties comparable to those of POPs and can thus be potentially hazardous to the environment. In addition, RFAs are expected to occur at lower concentrations than PCBs and PBDEs, whether in the biotic and abiotic compartments. Thus, one of the challenges of the present work was to develop a multiresidue method, based on gas chromatography coupled with a time-of-flight mass spectrometer, allowing for the simultaneous analysis of 17 RFAs at levels below ng.g-1. The levels and patterns of POP and RFA contamination were reported in the biotic and abiotic compartments of selected hydrosystems. The biomagnification potential of these compounds was also studied by determining trophic magnification factors (TMF) in the Gironde estuary and in the Rhône basin. In the Gironde estuary, it was shown that some RFA biomagnify as much or more than some historical POPs. Furthermore, in the Rhône basin, the use of TMF for predictive purpose, for BDE-47 or ΣPBDEs-WFD for example, was discussed and found possible

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26

Parladé, Molist Eloi. "Microbial communities driving emerging contaminant removal. Impact of treated wastewater on the ecosystem." Doctoral thesis, Universitat Autònoma de Barcelona, 2018. http://hdl.handle.net/10803/650400.

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Actualment, un dels nous reptes de la comunitat científica és fer front a l'increment de contaminants emergents als ambients naturals. La bioremediació s'ha perfilat com una bona alternativa per donar resposta a aquesta necessitat. El propòsit d'aquesta tesi ha estat estudiar les comunitats microbianes responsables de l'eliminació de contaminants emergents en diversos sistemes artificials, així com determinar l'impacte dels efluents resultants quan s'utilitzen com a aigua regenerada. Diferents tècniques moleculars i eines bioinformàtiques han permès caracteritzar els cultius d'enriquiment establerts, així com els bioreactors amb bacteris, algues i fongs, capaços d'eliminar contaminants. Els generes bacterians Dehalogenimonas i Dehalobacterium s'han identificat com a responsables de la degradació d'organohalonenats en dos cultius d'enriquiment i la seva microbiota acompanyant ha estat estat avaluada per posar de manifest possibles sinèrgies. Paral·lelament, s'ha caracteritzat la comunitat desenvolupada en un fotobioreactor a escala pilot durant l'eliminació de contaminants i productes farmacèutics a partir d'aigües residuals urbanes. Pel que fa a compostos estrogènics, s'ha demostrat una millor capacitat d'eliminació per part dels cultius d'enriquiment de microorganismes fototròfics en comparació amb cultius purs. A més a més, s'ha relacionat la presència de cianobacteris filamentosos amb una recuperació ràpida i eficaç de la biomassa fotosintètica. D'altra banda, s'ha analitzat la dinàmica de bacteris i fongs, així com de Trametes versicolor inoculat en bioreactors continus i biopiles fúngiques utilitzats per tractar aigues residuals hospitalàries i llots de depuradora. Tant el fong inoculat com algunes de les comunitats bacterianes indígenes s'han correlacionat amb l'eliminació d'alguns grups de fàrmacs. Finalment, s'ha evaluat l'impacte dels efluent obtinguts a partir de diferents tractaments d'aigues residuals hospitalàries irrigant microcosmos que mimetitzàven el sòl. Els resultats obtinguts han posat de manifest que els efluents fúngics es comporten de manera similar als controls negatius sense productes farmacèutics.
Rising awareness of pollutants not previously detected or monitored (emerging contaminants) has brought new challenges to the scientific community focused in environmental remediation. This thesis aimed to assess the microbial communities responsible of emerging contaminant removal in a variety of human-engineered systems as well as to evaluate the impact of the resulting effluents when they are used as reclaimed water. Molecular microbiology methods were used along with bioinformatic tools to assess the development of enrichment cultures and bioreactors driven by bacteria, algae and fungi, capable of pollutant removal. The bacterial genera Dehalogenimonas and Dehalobacterium were identified as the responsible of organohalide degradation in two enrichment cultures and their concomitant microbiota was assessed to denote putative synergies. The specialized community developed in a pilot-scale photobioreactor was also elucidated during urban wastewater treatment, with efficient removal of pollutants and pharmaceuticals. Efficiency of enrichment cultures, obtained from natural environments, over algal pure cultures was demonstrated in the removal of estrogenic compounds. Moreover, filamentous cyanobacteria were linked to a fast and efficient recovery of photosynthetic biomass. The dynamics of indigenous bacteria, fungi, and the inoculated strain of Trametes versicolor were assessed in continuous bioreactors and fungal biopiles treating hospital wastewater and sewage sludge, respectively. Both the inoculated fungus and some bacterial communities were correlated to the removal of pharmaceutical families. Finally, the effect of effluents obtained from fungal treatment over soil ecosystems were compared to conventionally-treated wastewater in laboratory model systems (microcosms), showing up a similar behavior to the negative controls that did not contain pharmaceuticals.

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Rementeria, Ugalde Ane. "Understanding the impact of silver as an emerging contaminant in the Ibaizabal and Gironde estuaries." Thesis, Bordeaux, 2016. http://www.theses.fr/2016BORD0443/document.

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Les estuaires ont été soumis à une forte pression humaine qui a entraîné la présence de polluants dans leurs eaux et sédiments, par exemple les métaux traces. Les estuaires du Golfe de Gascogne n’en sont pas une exception et les estuaires d’Ibaizabal et de la Gironde sont bien connus pour avoir des concentrations élevées de métaux. Dans ce contexte, les programmes de surveillance de l’environnement se sont appuyés sur l’utilisation des moules et des huîtres comme espèces sentinelles, car les analyses chimiques et biologiques de leurs tissus permettent d’évaluer l’état général de santé de leur environnement. Dans le but d’acquérir une meilleure compréhension des interactions entre la bioaccumulation et des effets toxiques du cuivre (Cu) et de l’argent (Ag) dans les huîtres Crassostrea gigas, ainsi que l’influence de facteurs environnementaux, le présent travail présente une étude de terrain et trois expériences de laboratoire. Parmi les résultats obtenus, on peut souligner que : (I) même si les huîtres et les moules peuvent indiquer correctement l’état de santé des estuaires du Golfe de Gascogne, une accumulation clairement plus élevée de métaux se produit dans les huîtres que dans les moules, (II) la voie d’exposition (directe ou alimentaire)induit des réponses de différentes intensités dans les huîtres, (iii) la toxicité de l’Ag est renforcée par la présence accrue de Cu dans les huîtres et (IV) la salinité a un faible effet sur la toxicité des métaux dans les huîtres
Estuaries have been subjected to a high human pressure which has led to the presence of pollutants in their waters and sediments including trace metals. The estuaries in the Bay of Biscay do not constitute an exception of this situation and the Ibaizabal and Gironde Estuaries are both very well known for having high metal concentrations in different compartments. In this context, environmental health monitoring programmes have relied on the use of mussels and oysters as sentinel organisms because chemical and biological analyses of their tissues allow assessing the general health status of their surrounding environment. The present work aims at acquiring a deeper understanding of the interactions between bioaccumulation and the toxic effects of copper (Cu) and silver (Ag) in oysters Crassostrea gigas, as well as the effects that environmental factors may have on them, For this, one field study and three laboratory experiments have been carried out. Among the most relevant results obtained it can be highlighted that: (I) both oysters and mussels are useful to properly indicate the health status of estuaries of the Bay of Biscay, yet higher accumulation of metals occurs in oysters than in mussels, (II) the intake pathway (watercolumn and/or food) induces different response intensities in oysters (III) the toxicity of Ag is enhanced in the presence of Cu in oysters and (IV) salinity has a low effect on the toxicity of both metals in oysters

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28

Barber, Dillon E. "Recovering social concern in the evangelical gospel." Theological Research Exchange Network (TREN), 2006. http://www.tren.com/search.cfm?p004-0127.

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29

Duan, Xiaodi. "Destruction of Chemicals of Emerging Concern using Homogeneous UV-254 nm Based Advanced Oxidation Processes." University of Cincinnati / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1535703502670581.

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30

Newton, Seth. "Legacy persistent organic pollutants and chemicals of emerging concern in Sweden : from indoor environments to remote areas." Licentiate thesis, Stockholms universitet, Institutionen för tillämpad miljövetenskap (ITM), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-97094.

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Bulk atmospheric deposition samples were taken every two months for a year in 2009-2010 at two sites in northern Sweden and analyzed for a suite of legacy and emerging persistent organic chemicals including legacy organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and novel flame retardants (NFRs). To further investigate the urban occurrence and contribution to remote contamination of flame retardants, indoor air, ventilation system air, and dust were sampled in several microenvironments in Stockholm during the winter of 2012 for analysis of PBDEs, isomer-specific hexabromocyclododecane (HBCDD), and NFRs. Outdoor air and soil samples were also sampled around the same time period for analysis of the same compounds. Five emerging pollutants were detected in atmospheric deposition: the current-use pesticides trifluralin and chlorothalonil; and the NFRs 1,2-dibromo-4-(1,2-dibromoethyl)cyclohexane (TBECH), 1,2-bis(tribromophenoxy)ethane (BTBPE), and Dechlorane Plus (DP). A decrease in the fraction of the anti isomer of DP was observed at the more remote site, indicating isomer-selective degradation or isomerization during long range atmospheric transport. The more remote site also received more total deposition of organic pollutants despite its receiving less precipitation. Although PBDEs and emerging organic pollutants were detected, the bulk of the deposition consisted of PCBs and hexachlorocyclohexanes (HCHs) at both sites. Several NFRs were identified in indoor and ventilation air samples including TBECH, pentabromotoluene (PBT), hexabromobenzene (HBB), 1,2-bis(pentabromodiphenyl)ethane (DBDPE), 2-ethylhexyl-2,3,4,5-tetrabromobenzoate (EHTBB), and bis(2-ethylhexyl)-3,4,5,6-tetrabromo-phthalate (TBPH). There was no significant difference between concentrations of contaminants in ventilation system air and indoor air indicating that the flame retardants included in this study reach the outdoor environment via ventilation systems. Dust and outdoor air samples have only been analyzed for HBCDDs so far. HBCDD concentrations in apartments, offices, and schools were lower than reported concentrations for other countries in similar microenvironments. However, an enrichment of α-HBCDD compared to γ-HBCDD was observed in dust taken from near treated products in stores when compared to dust taken directly from those products. Very low concentrations of HBCDDs were detected in outdoor air.

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Hussain, Sajjad. "Comparação entre diferentes processos de degradação do antibiótico sulfametoxazol." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/75/75134/tde-04072014-080157/.

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A ocorrência de produtos farmacêuticos e de cuidados pessoais no meio ambiente tem levado a preocupações sobre seu impacto ambiental e à saúde pública. O sulfametoxazol (SMX) é um fármaco que tem sido encontrado amplamente no ambiente. Neste estudo foi verificada a eficácia de vários processos, a saber eletroquímico, eletroquímico foto assistido, fotoquímico, Fenton e foto-Fenton, para a degradação de SMX em solução aquosa. A degradação eletroquímica e eletroquímica foto assistida foram realizadas em uma célula de fluxo do tipo filtro-prensa, usando um ânodo dimensionalmente estável comercial com composição nominal Ti/Ru0,3Ti0,7O2. Durante ambos os processos, efeitos de diferentes parâmetros foram analisados, como a natureza do eletrólito, a concentração de eletrólito suporte (NaCl) e a densidade de corrente aplicada. Os experimentos fotoquímicos, Fenton e foto-Fenton foram realizados em um reator de vidro cilíndrico de compartimento único. O efeito das concentrações inicias de Fe2+ e de H2O2 foram estudados para os processos Fenton e foto-Fenton. Similarmente, o efeito do pH inicial, a concentração inicial do SMX e a temperatura foram investigados para todos os processos. A variação da concentração de SMX foi determinada por cromatografia líquida de alta eficiência (CLAE) e a quantidade de matéria orgânica foi monitorada por análise de carbono orgânico total (COT). Os resultados obtidos indicaram que o SMX foi completamente degradado, porém, o COT foi apenas parcialmente removido em todos os processos. No período de tempo de ensaio estabelecido o aumento da densidade de corrente e da concentração de NaCl mais eficiente para a degradação e remoção de COT nos processos eletroquímicos. A quantidade de Fe2+ e H2O2 aumenta a eficiência do processo Fenton e foto-Fenton, e meio ácido foi favorável para todos os processos. O consumo de energia elétrica, baseado no parâmetro EEO (energia por ordem) mostrou que os processos eletroquímicos são energeticamente mais eficientes do que os fotoquímicos. As degradações acompanhadas por CLAE acoplado à espectrometria de massas, permitiu que vários intermediários fossem identificados, sendo então proposta uma sequência reacional para a degradação do SMX. O radical hidroxila e o cloro ativo atacam os anéis benzílico e isoxazólico, tendo sido demonstrado que os compostos iniciais formados foram os compostos hidrolisados e clorados. Os íons inorgânicos, tais como: NO3-, NH4+ e SO42-, também foram identificados durante os processos de degradação.
The occurrence of pharmaceuticals and personal care products in the environment has raised concerns about their impact upon environmental and public health. Sulfamethoxazole (SMX) is a pharmaceutical that has been found widely in the environment. This study investigated the effectiveness of various processes such as electrochemical, photo assisted electrochemical, photochemical, Fenton photo-Fenton to SMX degradation in aqueous solution. The electrochemical and photo-assisted electrochemical degradations were performed in a filter press type flow cell using a dimensionally stable anode with nominal composition of Ti/Ru0.3Ti0.7O2. During both these processes the effects of different parameters were analyzed, such as, nature of the electrolyte concentration of the supporting electrolyte (NaCl) and the applied current density. The photochemical, Fenton and photo - Fenton experiments were carried out in a single compartment cylindrical glass reactor. The effects initial iron concentrations and H2O2 were studied for Fenton and photo-Fenton processes. Similarly the effect of initial pH, initial concentration of SMX and temperature were investigated for all processes. The variation of SMX concentration was determined by high performance liquid chromatography (HPLC) and the amount of organic matter was monitored by analysis of total organic carbon (TOC). The results indicated that SMX was completely degraded, but TOC was partially removed in all processes studied, during experimental period the increase of the current density and NaCl concentration enhanced the degradation and TOC removal in the electrochemical processes. The amount of iron and H2O2 increases the efficiency of Fenton and photo-Fenton processes and acidic media was favorable for all processes. The electrical energy consumption parameter based on EEO (energy per order) was also evaluated and it was observed that the electrochemical processes are more energetically efficient than the photochemical. The degradations followed by HPLC coupled with mass spectrometry, in which several intermediates were identified and proposed a reaction sequence for the degradation of SMX. The hydroxyl radical and active chlorine attack benzene and isoxazólico rings, and has been demonstrated that the initial compounds formed were hydrolyzed and chlorinated compounds. Inorganic ions such NO3-, NH4+ and SO42- were also identified during degradation processes.

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32

Dhaniram, Danelle. "Chemicals of emerging concern in household products : a case study on the disposal of cosmetics in the United Kingdom." Thesis, Imperial College London, 2011. http://hdl.handle.net/10044/1/9281.

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Household products may contain chemicals of emerging concern (CECs) and their use and disposal can contribute to CECs being released to the environment with the potential to cause concern. Cosmetic products were used to exemplify the source-pathway-effect relationship for CECs, by investigating the use of cosmetics as a prospective pollutant source, their disposal, as a pathway for environmental contamination and, the potential need for effective management of CECs in products. Emphasis was placed on the Registration, Evaluation and Authorisation of Chemicals (REACH) legislation as a framework to consider the use of regulation to facilitate the assessment and management of CECs in household products. The CECs present in cosmetic products were identified, validated and quantified and, their potential environmental risks were assessed using a methodology developed under the REACH legislation guidelines. Findings demonstrated that once released in the environment, nanomaterials and triclosan have the potential to affect both aquatic and terrestrial organisms. Multi-criteria analysis was used to assess alternative risk management options for the use and disposal of these CECs in cosmetic products. The analysis indicated the need to manage some CECs in cosmetics to minimize the potential for environmental contamination. REACH has the potential to facilitate the management of these chemicals by shifting the legislative focus from disposal to prevention and minimization. The guidelines under REACH could be amended to improve the risk assessment and management process for CECs. This research demonstrated the efficacy of modifying the guidelines to produce sound assessments, whilst emphasising the need for effective management of CECs in cosmetic products.

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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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34

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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Martin, Sébastien. "Mécanismes de sorption et d'oxydoréduction à l'interface oxyde/solution : couplage chimie / transport." Thesis, Rennes 1, 2015. http://www.theses.fr/2015REN1S157.

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Au vu de l'omniprésence des oxydes de fer dans le milieu naturel, et en particulier la goethite et l'hématite qui sont les formes les plus stables, mais aussi de la prolifération des contaminants émergents dans l'environnement, comme les fluoroquinolones, notre objectif a été d'étudier leur réactivité et de définir les mécanismes de sorption et d'oxydoréduction à l'interface oxyde/solution dans des conditions statiques (batch) et hydrodynamiques contrôlées (colonne) en couplant une étude macroscopique (techniques chromatographiques, LC/MS, LC/UV) avec une approche microscopique (spectroscopie vibrationnelle et XPS) et de modélisation mécanistique (TPM et CD-MUSIC). Ces travaux mettent en évidence les principaux mécanismes responsables de la transformation des molécules organiques à la surface d'un oxyde de fer, et donc fournissent des informations nécessaires à la compréhension du devenir des contaminants émergents dans l'environnement
Given the ubiquity of iron oxides in environmental settings, particularly goethite and hematite, the most stable forms, but also the proliferation of emerging contaminants, such as fluoroquinolones, in the environment, our goal was to study their reactivity and describe mechanisms of sorption and redox at oxide /solution interfaces in static batch) and hydrodynamic conditions (column) by coupling a macroscopic study (LC/MS, LC/UV) with a microscopic/molecular approach (vibrational spectroscopy and XPS) and mechanistic modeling (TPM and CD-MUSIC).. These works highlight the main mechanisms responsible of the transformation of organic molecules on iron oxide surfaces and thus provide valuable information necessary for the understanding of the fate of emerging contaminants in the environment

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Ojemaye, Cecilia Yejide. "Identification and quantification of chemicals of emerging concern (persistence organic and inorganic pollutants) in some selected marine environments of Cape Town, South Africa." University of Western Cape, 2020. http://hdl.handle.net/11394/7697.

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Philosophiae Doctor - PhD
The increasing evidence of chemicals of emerging concern (CECs) in water bodies is causing major concern around the world because of their toxicological effects upon humans and aquatic organisms. 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. These compounds are often persistent but not regularly monitored because they are mostly still excluded from environmental legislation. Their fate and persistence in the environment are not well understood

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Bertoldi, Crislaine Fabiana. "Fotodegradação do contaminante emergente 2-(tiocianometiltio) benzotiazol (TCMTB) por meio de fotólise direta." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2017. http://hdl.handle.net/10183/169770.

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Os contaminantes emergentes são considerados compostos onipresentes em águas, portanto investigar a degradação e comportamento dessas substâncias torna-se necessária, pois é reportado que estes compostos causam efeitos adversos em seres vivos. O composto 2-(tiocianometiltio) benzotiazol (TCMTB), considerado um contaminante emergente, é amplamente empregado na indústria do couro como biocida com a finalidade de inibir o desenvolvimento de microrganismos na pele. Sendo assim, o objetivo do presente trabalho foi estudar a degradação do contaminante emergente TCMTB, por meio das técnicas de fotólise direta com radiação UV, radiação solar e oxidação com ozônio. Experimentos de fotólise direta do TCMTB, em soluções aquosas com diferentes concentrações, em efluente do processo de remolho e efluente simulado do remolho, foram conduzidos em reator com lâmpada de vapor de mercúrio (250 W). O teste de hidrólise foi realizado protegido da luz, a temperatura ambiente com diferentes concentrações do TCMTB para observar o comportamento do contaminante na ausência de luz. O maior coeficiente de absorção molar foi medido e identificado em 220 e 280 nm como 20489 e 11317 M-1 cm-1, respectivamente, para pH 5,0. Os resultados experimentais da fotodegradação mostraram que TCMTB foi rapidamente degradado por fotólise direta em soluções aquosas em 30 min de tratamento fotolítico. Os resultados do estudo do pH, demonstraram que pH interfere no processo fotoquímico, uma vez que em condições alcalinas o composto é mais estável e a taxa de fotodegradação diminui. Os ensaios com o efluente do processo de remolho mostraram que a degradação do TCMTB tem comportamento semelhante às soluções aquosas. O efluente simulado do remolho mostrou que uma alta concentração do contaminante leva a um maior tempo de irradiação de luz para a degradação. A aplicação de luz natural evidenciou degradação mais lenta, mas ainda assim, foi possível observar degradação de até 96% para a concentração de 6 mg L-1 em 420 min. A utilização do oxidante ozônio como tratamento, alcançou 40% de remoção do contaminante em 30 min, assinalando a alta estabilidade do composto. Portanto, este trabalho aponta o potencial do uso de fotólise direta (luz v artificial), ou radiação solar (luz natural) para a degradação de contaminantes emergentes como o 2 (tiocianometiltio) benzotiazol (TCMTB).
Emerging contaminants are considered omnipresent compounds in water, thus investigate the degradation and behavior of these substances becomes necessary as it is reported that these compounds cause adverse effects on living beings. The 2- (thiocyanomethylthio) benzothiazole compound (TCMTB), considered an emerging contaminant, is widely used in the leather industry as a microbicide for the purpose of inhibiting the development of microorganisms in the skin and leather. In this context, the purpose of the present work was to study the degradation of the emerging contaminant TCMTB by direct photolysis with UV radiation, solar radiation and ozone. Experiments of direct photolysis of the TCMTB in aqueous solutions with different concentrations, in the effluent from the soaking process were conducted in a reactor with mercury vapor lamp (250 W). The hydrolysis test was performed protected from light at room temperature with different concentrations of TCMTB to observe the behavior of the contaminant in the absence of light. The highest molar absorption coefficient was measured and identified at 220 and 280 nm as 20489 and 11317 M-1 cm -1, respectively, at pH 5.0. The experimental results of photodegradation showed that TCMTB was rapidly degraded by direct photolysis in aqueous solutions in 30 min of photolytic treatment. The results of the pH study showed that pH interfered in the photochemical process, since under alkaline conditions the compound is more stable and the photodegradation rate decreases. Assays of the direct photolysis in effluent from the soaking process have shown that TCMTB degradation behaves similarly to aqueous solutions. The direct photolysis of the the simulated effluent from the soaking showed that a high concentration of the contaminant leads to a longer time of light irradiation for degradation. The application of natural light evidenced slower degradation, however, it was possible to observe degradation of up to 96% for the 6 mg L-1 concentration with 420 min. The use of the ozone oxidant as a treatment, achieved 40% removal of the contaminant for 30 min of treatment, indicating the high stability of the compound. Therefore, this work highlights the potential of the use of direct photolysis (artificial light), or solar radiation (natural light) for the vii degradation of emerging contaminants such as 2 (thiocyanomethylthio) benzothiazole (TCMTB).

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Kandie, Faith Jebiwot [Verfasser], Werner [Gutachter] Brack, Henner [Gutachter] Hollert, and Jörg [Gutachter] Oehlmann. "Analytical screening of organic chemicals of emerging concern in western Kenya and their contribution to the prevalence of schistosomiasis / Faith Jebiwot Kandie ; Gutachter: Werner Brack, Henner Hollert, Jörg Oehlmann." Frankfurt am Main : Universitätsbibliothek Johann Christian Senckenberg, 2021. http://d-nb.info/122843252X/34.

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Kosera, Vitor Sena. "ESTUDO DA DEGRADAÇÃO DE TRICLOSAN VIA FOTOCATÁLISE HETEROGÊNEA UTILIZANDO SEMICONDUTOR LIVRE E IMOBILIZADO." UNIVERSIDADE ESTADUAL DE PONTA GROSSA, 2017. http://tede2.uepg.br/jspui/handle/prefix/2050.

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Made available in DSpace on 2017-07-24T19:37:55Z (GMT). No. of bitstreams: 1 Vitor Sena Kosera.pdf: 2784094 bytes, checksum: 960f241504b5d1829f16f8713f9dddad (MD5) Previous issue date: 2017-03-08
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
Triclosan is a compound with bactericidal effect that is frequently used in personal hygiene products. Recently, it has been found in surface water and wastewater even after conventional treatment. In the search for efficient alternative methods of degradation, are studied among them Oxidative Advanced Processes (AOPs), which are based on hydroxyl radical generation (HO), which is a strong oxidizing agent. The objective of this work was to study the degradation of triclosan using Heterogeneous Photocatalysis (HP), characterized by the use of a free and immobilized photocatalyst. In this work titanium dioxide (TiO2) and zinc oxide (ZnO) were used as photocatalysts. An analytical routine was established using High Performance Liquid Chromatography (HPLC) followed by partial validation. The determination of the TCS in aqueous solution was performed in the linear range of 0.1 to 10.0 mg L-1, with R2 = 0.999, limit of detection (LOD) 0.3 mg L-1 and limit of quantification (LOQ) 1. 0 mg L-1. The characterization of the catalysts allowed to identify for the TiO2 the anatase phase, with a bandgap of 3.22 eV. The immobilization of this catalyst in calcium alginate does not cause great damage to its activity, since the characterization of the spheres demonstrated that in fact the TiO2 was present in them, in an amount of 0,267 ± 0,058 mg per sphere, according to FEG images, had a rough surface. Complementing the characterization, the images by EDS also showed that the catalyst was evenly distributed throughout the surface. In the studies with ZnO as catalyst, we identified the wurtzite phase, with bandgap of 3.14 eV. In the same way as previously, the immobilization does not cause damage to its catalytic activity, as well as the morphology of its spheres are being very close to TiO2 and also with surface distribution in all the analyzed areas (0.267 ± 0.058 mg ZnO per sphere). Also, a factorial design of experiments was carried out, where the best conditions found for both catalysts were pH 10 and 30 mg L-1. The kinetics of degradation demonstrated that the photolysis followed a first-order reaction whereas for the others the order followed was of pseudo-first order. The half-life times between free and immobilized studies did not show large variations, but TiO2 was slightly higher than ZnO. As good results with artificial radiation were achieved, studies with solar radiation were performed. The photolysis continued with a first order of reaction (t1/2 = 16.98 min) while the FH with immobilized TiO2 continued to follow a pseudo-first order (t1/2 = 22.88 min). The ZnO changed to second order (T1/2 = 11.72 min), demonstrating good efficiency using a renewable source of radiation. In the mineralization studies, TOC analysis were used to monitor the total organic matter removal of the samples. In these studies TiO2 presented a great advantage in relation to photolysis, because with about 18h of reaction, the photocatalysis was able to mineralize amounts greater than 90% while the photolysis was only about 40%. This difference was not so great for ZnO, because with this time there was a gain of approximately 10%, but it also showed superiority. These differences are easily observed using the half-life times, where for the photolysis the mineralization followed a first-order reaction with t1/ 2 = 1565 min, while the TiO2 and ZnO followed a second-order reaction with t1/2 = 76.14 min and t1/2 = 1354 min respectively.
O triclosan é um composto com ação bactericida e bastante utilizado em produtos de higiene pessoal. Recentemente, tem sido encontrado em águas superficiais e efluentes mesmo após tratamento convencional. Na busca de métodos mais eficientes de degradação, métodos alternativos têm sido estudados, estando entre eles os Processos Avançados de Oxidação (PAOs), os quais são baseados na geração do radical hidroxila (HO•), que é um forte agente oxidante. Sendo assim o objetivo deste trabalho foi estudar a degradação do triclosan utilizando a Fotocatálise Heterogênea (FH), caracterizada pelo uso de um fotocatalisador em suspensão e imobilizado. Neste trabalho foram utilizados como fotocatalisadores o dióxido de titânio (TiO2) e o óxido de zinco (ZnO). Foi realizado o estabelecimento de uma rotina analítica utilizando-se cromatografia líquida de alta eficiência (CLAE) seguido da validação parcial. A determinação do TCS em solução aquosa foi realizada na faixa linear de 0,1 a 10 mg L-1, com R2=0,999, limite de detecção (LD) 0,3 mg L-1 e limite de quantificação (LQ) 1,0 mg L-1. A caracterização dos catalisadores permitiu identificar para o TiO2 a fase anatase, com bandgap de 3,22 eV. A imobilização deste catalisador em alginato de cálcio não trouxe grandes prejuízos a sua atividade, pois a caracterização das esferas demonstrou que de fato o TiO2 estava presente nelas, numa quantidade de 0,267±0,058 mg por esfera, a qual possuía, segundo imagens por FEG, uma superfície rugosa. Complementando a caracterização as imagens por EDS demonstraram também que o catalisador estava distribuído de forma uniforme por toda a superfície. Nos estudos com o ZnO como catalisador, identificou-se a fase wurtzita, com bandgap de 3,14 eV. Da mesma maneira que anteriormente, a imobilização não acarretou em prejuízos na sua atuação catalítica, além da morfologia de suas esferas serem muito próximas das do TiO2 e também com distribuição superficial por todas as áreas analisadas (0,267±0,058 mg de ZnO por esfera). Também foi realizado um planejamento fatorial de experimentos onde para ambos catalisadores as melhores condições encontradas foram de pH 10 e 30 mg L-1. As cinéticas de degradação demonstraram que a fotólise segue uma reação de primeira ordem enquanto que para as demais a ordem foi de pseudo-primeira ordem. Os tempos de meia-vida entre os estudos em suspensão e imobilizados não apresentaram grandes variações, mas o TiO2 foi ligeiramente superior ao ZnO. Como bons resultados com radiação artificial foram alcançados, estudos com radiação solar foram realizados. Nestes a fotólise segue uma cinética de reação de primeira ordem (t1/2 = 16,98 min) enquanto que as FH com TiO2 imobilizado segue uma reação de pseudo-primeira ordem (t1/2= 22,88 min). Para o ZnO a ordem da reação encontrada foi de segunda ordem (t1/2=11,72 min), demonstrando boa eficiência quando utiliza-se uma fonte renovável de radiação. Nos estudos de mineralização, avaliou-se a remoção do carbono orgânico total (COT) após tempos pré-determnados. Nestes estudos o TiO2 utilizado como semicondutor em suspensão apresentou ampla vantagem em relação a fotólise, pois com cerca de 18h de reação, a fotocatálise conseguiu mineralizar quantidades superiores a 90% enquanto que a fotólise foi de apenas cerca de 40%. Esta diferença não foi tão significativa para o ZnO, pois neste a diferença foi aproximadamente 10%, mas demonstrou também superioridade em relação a fotólise. Estas diferenças são facilmente observadas utilizando os tempos de meia-vida, onde para a fotólise a mineralização seguiu uma reação de primeira ordem com t1/2 = 1565 min, enquanto que o TiO2 e o ZnO seguiram uma reação de segunda ordem com t1/2 = 76,14 min e t1/2=1354 min, respectivamente.

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Murad, Hassan. "Membranbioreaktorer och deras förmåga att avlägsna prioriterade mikroföroreningar." Thesis, Uppsala universitet, Institutionen för teknikvetenskaper, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-366881.

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Spridning av läkemedelsrester och andra prioriterade mikroföroreningar i miljön har uppmärksammats och stor oro väckts kring problematiken. Bland observationer som forskare har noterat till följd av antibiotika, hormoner och läkemedel i vattenmiljöer är bland annat bakteriell resistens, könsbyte och sterilitet hos fisk och groddjur. Persistenta föroreningar som per- och polyfluor alkalysyror (PFAS) bryts inte heller ner i naturen och mikroskräppartiklar kan anrikas i vattendrag och orsaka negativa effekter på vattenlevande organismer. Gemensamt för mikroföroreningar är att dessa förekommer oftast i små halter och kan härstamma från olika mänskliga aktiviteter. Avloppsreningsverk (ARV) är inte primärt anpassade för att avskilja mikroföroreningar utan främst för att avlägsna kväve, fosfor och organiskt material. Uppströmsarbete är inte heller tillräckligt effektivt för att avlasta reningsprocessen vilket medför att mängden mikroföroreningar ökar i vattenmiljöer och sätter ytterligare påtryckningar på ARV. Utmaningar som ARV står inför idag med nya mikroföroreningar och förekomsten av dessa i miljön har väckt frågor både nationellt och internationellt. Stockholm Vatten och Avfalls (SVOA) beslut att implementera membranbioreaktor (MBR) på Henriksdals reningsverk av porstorleken 0,04 μm är en åtgärd för att rusta upp inför framtida hydrauliska volymer men även potentiella striktare reningskrav. Fördelen med MBR-processen är att den förhindrar föroreningar som förekommer partikulärt att passera membranen och på så sätt hindras skadliga ämnen att passera reningsprocessen. I dagsläge saknas krav på ARV att rena avloppsvatten från de flesta mikroföroreningar. Det förväntas dock att kommande lagstiftning omfattar läkemedel och andra organiska föroreningar. I detta projekt undersöktes mikroföroreningar i form av läkemedelsrester, antibiotika, hormoner, PFAS och mikroskärp i en MBR-process samt förekomsten av adsorberbara och extraherbara organiska halogener (AOX, EOX) som potentiellt bildas under rengöring av membranen till följd av reningsprocessen. Resultat från detta projekt med MBR-processen visade en generell högre reduktion av prioriterade mikroföroreningar i avloppsvatten än tidigare undersökningar på konventionella ARV, med undantag för några substanser som visade på en liknande sämre reduktion. Läkemedlen diklofenak, oxazepam, citalopram med flera visade på en sämre reduktion och lika så för antibiotikumen clindamycin, claritomycin och erytromycin där reduktionen var negativ och visade på en återkommande trend. Östrogena hormoner reducerades i reningsprocessen och likaså för mikroskräp där 60 partiklar/m3 mikroplast av porstorleken större än 300 μm passerade membranen. Mikroplast av en porstorlek i intervallet mindre än 300 men större än 50 μm passerade 140 partiklar/m3 membranen. För AOX och EOX var halten i MBR-processen typiska och i nivå med tidigare undersökningar genomförda på konventionella ARV. Eftersom membranen inte kan avskilja partiklar på molekylnivå visades sig även att det passerade fortfarande mikroföroreningar som undersöktes. En slutsats från detta projekt är att endast ett få tal ämnen reducerades helt medan majoriteten av de prioriterade mikroföroreningarna reducerades delvis i avloppsvatten. För att kunna reducera dessa prioriterade mikroföroreningar i reningsprocessen ytterligare om striktare reningskrav skulle bli aktuella krävs vidare efterbehandling efter MBR-processen.
Release of pharmaceutical residues and other emerging substances in the environment has been highlighted and raised a great concern regarding the issue. Among observations that scientists have noted as a result of antibiotics, hormones and pharmaceutical residues in the aquatic environment are bacterial resistance, sex change and sterility in fish and batrachians. Persistent pollutants such as perfluorinated-alkylated substances (PFAS) are also not degraded in nature, and microscopic debris particles can be enriched in aquatic systems and cause adverse effects on aquatic organisms. The common aspect with these substances is that they usually occur in small quantities and can derive from different human activities. Wastewater treatment plants (WWTP) are not primarily designed to separate emerging substances of concern (ESOC), but primarily to remove nitrogen, phosphorus and particulate organic matter. Upstream work is also not sufficiently effective to relieve the purification process, which means that the amount of pollutants increases in aquatic environments and puts additional pressure on the WWTP. The challenges facing WWTP today with ESOC and their presence in the environment has raised issues both nationally and internationally. Stockholm Vatten och Avfall (SVOA) decision to implement a membrane bioreactor (MBR) with poresize of 0,04 μm at Henriksdal WWTP is a step to prepare for future hydraulic volumes, but also potentially stricter treatments requirements regarding ESOC. The advantage of the MBR process is that it prevents contaminants that appear to be particulate to pass the membranes and end up in the receiving waters. Today, WWTP are not required to treat wastewater in order to remove pharmaceutical residues, antibiotics, hormones, PFAS or microscopic debris particles. However, it is expected that future legislations will include pharmaceuticals and other organic pollutants. In this project, ESOC such as pharmaceutical residues, antibiotics, hormones, PFAS and microscopic debris in the MBR-process are studied as well as the presence of adsorbable and extractable organic halogens (AOX, EOX) that are possibly formed during the cleaning or maintains of the membranes. Results from this study showed a higher general reduction of the studied ESOCs in wastewater with the MBR-process than previous studies in conventional WWTP, except of some substances that showed a poor reduction. Pharmaceuticals such as diclofenac, oxazepam and citalopram showed a weak reduction as well as the antibiotics clindamycin, clarithromycin and erythromycin where they showed a higher outcome levels than the incoming to the treatment process. Estrogenic hormones were reduced in the purification process as well as microplastics where only 60 particles/m3 of pore size higher than 300 μm passed the membranes. Microplastics of the pore size smaller than 300 and larger than 50 μm were detected to 140 particle/m3 in the effluent water. For AOX and EOX, the level of MBR process showed typical values and were in line with previous studies on conventional ARV. However, since the membranes cannot treat contaminants at molecular level, it was also shown that some ESOC that were studied bypassed the treatment process. A conclusion from this project is that only a few numbers of substances were fully reduced while the majority of ESOCs were partially reduced in wastewater. In order to reduce further ESOCs and in case of stricter treatment were to be applied, additional post-treatment is also needed for the MBR process.

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Sousa, João Carlos Gonçalves de. "Determination of Contaminants of Emerging Concern in Surface Water." Dissertação, 2016. https://hdl.handle.net/10216/89720.

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Sousa, João Carlos Gonçalves de. "Determination of Contaminants of Emerging Concern in Surface Water." Master's thesis, 2016. https://hdl.handle.net/10216/89720.

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"Use of Ozonation and Constructed Wetlands to Remove Contaminants of Emerging Concern from Wastewater Effluent." Doctoral diss., 2013. http://hdl.handle.net/2286/R.I.20797.

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abstract: Contaminants of emerging concern (CECs) present in wastewater effluent can threat its safe discharge or reuse. Additional barriers of protection can be provided using advanced or natural treatment processes. This dissertation evaluated ozonation and constructed wetlands to remove CECs from wastewater effluent. Organic CECs can be removed by hydroxyl radical formed during ozonation, however estimating the ozone demand of wastewater effluent is complicated due to the presence of reduced inorganic species. A method was developed to estimate ozone consumption only by dissolved organic compounds and predict trace organic oxidation across multiple wastewater sources. Organic and engineered nanomaterial (ENM) CEC removal in constructed wetlands was investigated using batch experiments and continuous-flow microcosms containing decaying wetland plants. CEC removal varied depending on their physico-chemical properties, hydraulic residence time (HRT) and relative quantities of plant materials in the microcosms. At comparable HRTs, ENM removal improved with higher quantity of plant materials due to enhanced sorption which was verified in batch-scale studies with plant materials. A fate-predictive model was developed to evaluate the role of design loading rates on organic CEC removal. Areal removal rates increased with hydraulic loading rates (HLRs) and carbon loading rates (CLRs) unless photolysis was the dominant removal mechanism (e.g. atrazine). To optimize CEC removal, wetlands with different CLRs can be used in combination without lowering the net HLR. Organic CEC removal in denitrifying conditions of constructed wetlands was investigated and selected CECs (e.g. estradiol) were found to biotransform while denitrification occurred. Although level of denitrification was affected by HRT, similar impact on estradiol was not observed due to a dominant effect from plant biomass quantity. Overall, both modeling and experimental findings suggest considering CLR as an equally important factor with HRT or HLR to design constructed wetlands for CEC removal. This dissertation provided directions to select design parameters for ozonation (ozone dose) and constructed wetlands (design loading rates) to meet organic CEC removal goals. Future research is needed to understand fate of ENMs during ozonation and quantify the contributions from different transformation mechanisms occurring in the wetlands to incorporate in a model and evaluate the effect of wetland design.
Dissertation/Thesis
Ph.D. Civil and Environmental Engineering 2013

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Barbosa, Marta Sofia Oliveira. "Determination of priority substances and contaminants of emerging concern in drinking water and their removal by chemical processes." Dissertação, 2015. https://repositorio-aberto.up.pt/handle/10216/88742.

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Barbosa, Marta Sofia Oliveira. "Determination of priority substances and contaminants of emerging concern in drinking water and their removal by chemical processes." Master's thesis, 2015. https://repositorio-aberto.up.pt/handle/10216/88742.

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"Contaminants of Emerging Concern in U.S. Sewage Sludges and Forecasting of Associated Ecological and Human Health Risks Using Sewage Epidemiology Approaches." Doctoral diss., 2013. http://hdl.handle.net/2286/R.I.20885.

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abstract: Many manmade chemicals used in consumer products are ultimately washed down the drain and are collected in municipal sewers. Efficient chemical monitoring at wastewater treatment (WWT) plants thus may provide up-to-date information on chemical usage rates for epidemiological assessments. The objective of the present study was to extrapolate this concept, termed 'sewage epidemiology', to include municipal sewage sludge (MSS) in identifying and prioritizing contaminants of emerging concern (CECs). To test this the following specific aims were defined: i) to screen and identify CECs in nationally representative samples of MSS and to provide nationwide inventories of CECs in U.S. MSS; ii) to investigate the fate and persistence in MSS-amended soils, of sludge-borne hydrophobic CECs; and iii) to develop an analytical tool relying on contaminant levels in MSS as an indicator for identifying and prioritizing hydrophobic CECs. Chemicals that are primarily discharged to the sewage systems (alkylphenol surfactants) and widespread persistent organohalogen pollutants (perfluorochemicals and brominated flame retardants) were analyzed in nationally representative MSS samples. A meta-analysis showed that CECs contribute about 0.04-0.15% to the total dry mass of MSS, a mass equivalent of 2,700-7,900 metric tonnes of chemicals annually. An analysis of archived mesocoms from a sludge weathering study showed that 64 CECs persisted in MSS/soil mixtures over the course of the experiment, with half-lives ranging between 224 and >990 days; these results suggest an inherent persistence of CECs that accumulate in MSS. A comparison of the spectrum of chemicals (n=52) analyzed in nationally representative biological specimens from humans and MSS revealed 70% overlap. This observed co-occurrence of contaminants in both matrices suggests that MSS may serve as an indicator for ongoing human exposures and body burdens of pollutants in humans. In conclusion, I posit that this novel approach in sewage epidemiology may serve to pre-screen and prioritize the several thousands of known or suspected CECs to identify those that are most prone to pose a risk to human health and the environment.
Dissertation/Thesis
Ph.D. Civil and Environmental Engineering 2013

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"Organic Matter Occurrence in Arizona and Innovative Treatment by Granular Activated Carbon." Doctoral diss., 2012. http://hdl.handle.net/2286/R.I.14687.

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abstract: Population growth and fresh water depletion challenge drinking water utilities. Surface water quality is impacted significantly by climate variability, human activities, and extreme events like natural disasters. Dissolved organic carbon (DOC) is an important water quality index and the precursor of disinfection by-products (DBPs) that varies with both hydrologic and anthropogenic factors. Granular activated carbon (GAC) is a best available technology for utilities to meet Stage 2 D/DBP rule compliance and to remove contaminants of emerging concern (CECs) (e.g., pharmaceutical, personal care products (PCPs), etc.). Utilities can operate GAC with more efficient and flexible strategies with the understanding of organic occurrence in source water and a model capable predicting DOC occurrence. In this dissertation, it was found that DOC loading significantly correlated with spring runoff and was intensified by dry-duration antecedent to first flush. Dynamic modeling based on reservoir management (e.g., pump-back operation) was established to simulate the DOC transport in the reservoir system. Additionally, summer water recreational activities were found to raise the level of PCPs, especially skin-applied products, in raw waters. GAC was examined in this dissertation for both carbonaceous and emerging nitrogenous DBP (N-DBP) precursors (i.e., dissolved organic nitrogen (DON)) removal. Based on the experimental findings, GAC preferentially removes UV254-absorbing material, and DOC is preferentially removed over DON which may be composed primarily of hydrophilic organic and results in the low affinity for adsorption by GAC. The presence of organic nitrogen can elevate the toxicity of DBPs by forming N-DBPs, and this could be a major drawback for facilities considering installation of a GAC adsorber owing to the poor removal efficiency of DON by GAC. A modeling approach was established for predicting DOC and DON breakthrough during GAC operation. However, installation of GAC adsorber is a burden for utilities with respect to operational and maintenance cost. It is common for utilities to regenerate saturated GAC in order to save the cost of purchasing fresh GAC. The traditional thermal regeneration technology for saturated GAC is an energy intensive process requiring high temperature of incineration. Additionally, small water treatment sites usually ship saturated GAC to specialized facilities for regeneration increasing the already significant carbon footprint of thermal regeneration. An innovative GAC regeneration technique was investigated in this dissertation for the feasibility as on-site water treatment process. Virgin GAC was first saturated by organic contaminant then regenerated in-situ by iron oxide nanocatalysts mixed with hydrogen peroxide. At least 70 % of adsorption capacity of GAC can be regenerated repeatedly for experiments using modeling compound (phenol) or natural organic matter (Suwannee River humic acid). The regeneration efficiency increases with increasing adsorbate concentration. Used-iron nanocatalysts can be recovered repeatedly without significant loss of catalytic ability. This in-situ regeneration technique provides cost and energy efficient solution for water utilities considering GAC installation. Overall, patterns were found for DOC and CEC variations in drinking water sources. Increasing concentrations of bulk (DOC and DON) and/or trace organics challenge GAC operation in utilities that have limited numbers of bed-volume treated before regeneration is required. In-situ regeneration using iron nanocatalysts and hydrogen peroxide provides utilities an alternative energy-efficient operation mode when considering installation of GAC adsorber.
Dissertation/Thesis
Ph.D. Civil and Environmental Engineering 2012

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"Predicting De Facto Reuse Impacts on Drinking Water Sources at Small Public Water Systems." Doctoral diss., 2020. http://hdl.handle.net/2286/R.I.63089.

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abstract: De facto potable reuse (DFR) occurs when surface water sources at drinking water treatment plants (DWTPs) contain treated effluents from upstream wastewater treatment plants (WWTPs). Contaminants of emerging concerns (CECs) originate from treated effluents (e.g., unregulated disinfection by-products, pathogenic microorganisms as Cryptosporidium oocyst, Giardia cyst, and Norovirus) can be present in surface water and pose human health risks linked to CECs. Previously developed De facto Reuse Incidence in our Nations Consumable Supply (DRINCS) model predicted DFR for the national largest DWTPs that serve >10,000 people (N = 2,056 SW intakes at 1,210 DWTPs). The dissertation aims to quantify DFR at all surface water intakes for smaller DWTPs serving ≤10,000 people across the United States and develop a programmed ArcGIS tool for proximity analysis between upstream WWTPs and DWTPs. The tested hypothesis is whether DWTPs serving ≤10,000 people are more likely to be impacted by DFR than larger systems serving > 10,000 people.The original DRINCS model was expanded to include all smaller DWTPs (N = 6,045 SW intakes at 3,984 DWTPs) in the U.S. First, results for Texas predicted that two-thirds of all SW intakes were impacted by at least one WWTP upstream. The level of DFR at SW intakes in Texas ranged between 1% to 20% under average flow and exceeded 90% during mild droughts. Smaller DWTPs in Texas had a higher frequency of DFR than larger systems while < 10% of these DWTPs employed advanced technology (AT) capable of removing CECs. Second, nationally over 40% of surface water intakes at all DWTPs were impacted by DFR under average flow (2,917 of 6,826). Smaller DWTPs had a higher frequency (1,504 and 1,413, respectively) of being impacted by upstream WWTP discharges than larger DWTPs. Third, the difference in DFR levels at smaller versus larger DWTPs was statistically unclear (t-test, p = 0.274). Smaller communities could have high risks to CECs as they rely on surface water from lower-order streams impacted by DFR. Furthermore, smaller DWTPs lack more than twice as advanced unit processes as larger DWTPs with 52.1% and 23%, respectively. DFR levels for DWTPs serving > 10,000 people were statistically higher on mid-size order streams (3, 5, and 8) than those for smaller DWTPs. Finally, DWTPs serving > 10,000 people could pose risks to a population impacted by DFR > 1% as 40 times as those served by smaller DWTPs with 71 million and 1.7 million people, respectively. The total exposed population to risks of CECs served by DWTPs impacted by upstream WWTP discharges (DFR >10%) was estimated at 12.3 million people in the United States. Future studies can use DRINCS results to conduct an epidemiological risk assessment for impacted communities and identify communities that would benefit from advanced technology to remove CECs.
Dissertation/Thesis
Doctoral Dissertation Civil, Environmental and Sustainable Engineering 2020

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49

Silva, Adriano S. "Treatment of wastewater containing pharmaceutical compounds by catalytic wet peroxide oxidation using clay-based materials as catalysts." Master's thesis, 2018. http://hdl.handle.net/10198/19537.

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Dupla diplomação UTFPR
This work deals with the treatment of wastewater containing paracetamol, used as a model pharmaceutical emergent pollutant, by catalytic wet peroxide oxidation using clay-based materials as catalysts. The catalysts prepared in this work were clays activated through acid treatment and clays pillared with Co and Fe. For the preparation, natural clays from four different regions of Kazakhstan were used: Akzhar, Asa, Karatau and Kokshetau. The FTIR analysis showed that the pillared clays have a higher amount of iron in its structure when compared with the natural materials, suggesting that the intercalation of iron was successful. The N2 adsorption isotherms obtained were classified as Type II, typical of macroporous materials. The acid characterization showed that the procedures used for the preparation of the acid activated clays and of the pillared clays caused structural modifications. After the preparation and characterization, the pillared materials were tested in the degradation of paracetamol by catalytic wet peroxide oxidation (CWPO). Paracetamol concentration, hydrogen peroxide concentration and total organic carbon analysis (TOC) were followed against time. The material with the best activity was the Kokshetau pillared clay (KOP), with a complete conversion of the pollutant being obtained between 240 and 360 minutes of reaction, followed by a negligible iron leaching of 0.011 %. This leaching left the reaction system with a concentration of 0.089 mg/L of Fe, which is lower than the limit established by the European legislation for discharge in natural water courses (2 mg/L). Since the Kokshetau pillared clay presented the best result, other Kokshetau-based samples (activated, calcined and natural) were also tested in the CWPO of paracetamol. The higher efficiency of KOP in the CWPO of paracetamol can be explained by the fact that this material has a higher acidity, basicity and surface area when compared to the other pillared samples.
Este trabalho aborda o tratamento de águas residuais que contém paracetamol, como poluente emergente modelo, por oxidação humida com peróxido de hidrogênio usando argilas como catalisadores. Os catalisadores a base de argila preparados neste trabalho foram as argilas ativadas mediante tratamento com ácido e as argilas pilarizadas com Cobalto e Ferro. Para o preparo, foram utilizadas argilas naturais de quatro regiões diferentes no Cazaquistão: Akzhar, Asa, Karatau e Kokshetau. A análise de FTIR mostrou que as argilas pilarizadas possuem uma maior quantidade de Ferro na sua estrutura quando comparado com os outros materiais, o que pode indicar que o processo de intercalação do metal na estrutura da argila obteve sucesso. Os resultados obtidos para as isotermas de adsorção de N2 foram usados para classificar o material como Tipo II, atribuída a materiais macroporoso. A caracterização ácida mostrou que os procedimentos usados para preparar a argila pilarizada e a argila ativada causaram modificações estruturais no material. Após a preparação e caracterização, as argilas pilarizadas foram testadas na degradação do paracetamol por meio da catálise húmida com peróxido de hidrogênio. A fim de avaliar a variação da concentração de paracetamol, peróxido de hidrogênio e a variação do teor de carbono orgânico total, amostras foram coletadas em diferentes tempos. O material com a melhor atividade foi a amostra de argila Kokshetau pilarizada (KOP), apresentando uma conversão completa do poluente entre 240 e 360 minutos de reação e uma quantidade de Ferro lixiviado de 0.011%. Essa porcentagem de lixiviação deixou o sistema reativo com uma concentração de Ferro de 0.089 mg/L, um valor menor que o valor limite estabelecido pela legislação (2 mg/L). Como entre as pilarizadas a amostra de Kokshetau demonstrou o melhor resultado, outras amostras a base de Kokshetau (ativada, calcinada e natural) também foram testadas na CWPO do paracetamol. O melhor desempenho da Kokshetau pilarizada pode ser justificado pelo fato de o material possuir uma maior quantidade de acidez, basicidade e área superficial com relação as outras argilas pilarizadas.
To VALORCOMP for the financial support and to LSRE-LCM for the opportunity to acquire knowledge in the catalysis field.

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50

Yen, Chia-Heng, and 顏嘉亨. "The Use of Simultaneous Electrocoagulation and Electrofiltration Process Coupled with Lab-Prepared Tubular Carbonaceous/Ceramic Composite Membranes for the Removal of Contaminants of Emerging Concern in Aqueous Solutions." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/96749978954602673536.

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博士
國立中山大學
環境工程研究所
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This study investigated the occurrence and removal efficiencies of 8 phthalate esters, Bisphenol A, Nonylphenol, 18 antibiotics, and 10 non-antibiotics present in the influent of a sewage treatment plant (STP), tap water, and drinking fountain water on a selected campus in southern Taiwan. To this end, a monitoring program was conducted and a novel laboratory-prepared tubular carbonaceous/alumina composite membrane (TCACM) was incorporated into the simultaneous electrocoagulation and electrofiltration (EC/EF) treatment module to remove the emerging contaminants (ECs) from water samples. The monitoring results showed that at least three kinds of ECs present in each of the abovementioned aqueous solutions. It was found that the influent of selected campus STP contained cephalexin and caffeine with concentrations up to 5199 ng/L and 915 ng/L, respectively. Three PAEs (i.e., di-n-butyl phthalate (DnBP), di-(2-ethylhexyl) phthalate (DEHP), and di-iso-nonyl phthalate (DiNP)) were usually detected in tap water and drinking fountain water of concern with average concentrations ranging from 16 to 93 ng/L. Four kinds of lab-perpared membrane, including tubular alumina membrane (TAM), tubular hydrophobically modified TAM, tubular titania/alumina composite membrane (TTACM), and TCACM, were used to investigate relevant removal mechanisms for ECs of concern in model solution. It was found that the removal efficiencies were significantly higher (10-20%) for the tubular hydrophobically modified TAM as compared with TAM. When carbon nanofibers (CNFs) layer was grown on TAM, this membrane would yield a much greater removal efficiency as compared with TTACM, for example, the removal efficiency of caffeine could increase from 46% to 69%. The test results of the EC/EF process coupled with the TCACMs were also discussed. In model solution, removal efficiencies of over 60% were obtained for all ECs of concern. The synergistic effect of electrocoagulation and electrofiltration was considered as a probable mechanism. For the influent of campus STP, the said synergistic effect yielded the removal efficiencies up to 93% for DnBP, 95% for DEHP, 92% for DiNP, 96% for cephalexin, 95% for ciprofloxacin, 95% for caffeine, and 90% for sulfamethoxazole. Additionally, natural organic matter (NOM) was believed to enhance the removal of ECs from the influent of campus STP. It was also found that 69-72% removal efficiencies of ECs could be obtained in treatment tests of tap water. Effects of electrocoagulation and adsorption of CNFs are believed to be responsible for this finding. According to the analysis based on the resistance in series model, the EC/EF process coupled with the TCACM yielded a lower irreversible resistance of membrane, resulting in a longer membrane life.

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