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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Enzymatic treatment of pharmaceuticals and personal care products (PPCPs) in municipal wastewater

Sharkey, Margaret E 29 October 2013 (has links)
Conventional wastewater treatment plants do not effectively remove pharmaceuticals and personal care products (PPCPs). As a result, PPCPs enter the environment via treated wastewater discharge. Enzymatic treatment, using the laccasemediator system, is a novel biochemical process that has been shown to effectively treat some PPCPs. This study investigates the efficacy of the laccase-mediator system to treat PPCPs using a process that can be easily implemented at an existing wastewater treatment plant. Enzymatic treatment will be most beneficial after primary sedimentation and before conventional biological treatment, where unoxidized PPCPs and byproducts could have the opportunity for further degradation in biological treatment. In this work, two enzymatic treatment configurations were studied. A step-wise optimization process was used that alternately varied treatment conditions: pH, enzyme activity, mediator concentration, and reactor detention time. In the optimization process of each configuration, successful oxybenzone removal (~90%) was achieved in municipal primary effluent. In a direct comparison of treatment configurations, both resulted in vi similar percent removals of oxybenzone. Therefore, the configuration with the simpler operation and reactor design was chosen for further study. During the optimization process, several noteworthy conclusions were made that might have full-scale enzymatic treatment implications. Specifically, successful oxybenzone removal occurred at unadjusted pH and without aeration, but increased biological oxygen demand of the wastewater increased the required mediator concentration. While the first finding would decrease enzymatic treatment costs, the latter would increase the costs associated with the mediator. Thus, an alternative mediator source, specifically one high in phenolic compounds, is desired. The use of wine, as a surrogate of winery wastewater, was in investigated and proved ineffective. Further investigation of alternative mediator sources is required. Treatment of another PPCP, sulfamethoxazole, was less efficient (65% removal) than that of oxybenzone, but nevertheless, the substantial removal might indicate that other PPCPs can be treated with the laccase-mediator system. The most promising result of this work was the simultaneous treatment of multiple PPCPs, oxybenzone and sulfamethoxazole. Simultaneous treatment proved to be as effective as when each PPCP was treated individually. / text
2

Assessment of Mosquitofish (Gambusia affinis) Downstream of Domestic Wastewater Effluents in the Bayous of Harris County

Watkins, Crystal 2011 December 1900 (has links)
The introduction of pharmaceuticals and personal care products (PPCPs) to aquatic systems has impacted development and reproductive health of fish in many regions of the world. This study investigated western mosquitofish in the bayou systems of Harris County, Texas for evidence of morphological and reproductive abnormalities. Mosquitofish were sampled above and below WWTPs on five streams during May and August 2010, and specimens were dissected and analyzed for reproductive (egg/embryo weight, embryo/egg number and embryos staging), morphological (liver and gonad weight, body length, gonadosomatic index and hepatosomatic index) and histological indicator variables. In addition, water samples were analyzed for concentrations of PPCPs. Spatial and temporal variation was observed among all indicator variables, however no consistent differences were found above versus below WWTP discharges. Histopathology showed no evidence of lesions or presence of intersex individuals. Chemical analysis revealed a variety of pharmaceuticals and anthropogenic chemicals present in the Houston area waterways, however all were at concentrations lower than those known to cause impacts to fishes. These results suggest that the current concentrations of chemicals being discharged from WWTPs into headwater reaches of streams in the suburban area of west Houston are below levels that impact the physiology of male and female mosquitofish.
3

The Chlorination of Pharmaceuticals and Other Phenolic Compounds in the Presence of Iodide

Fiss, Edward Matthew 06 May 2009 (has links)
Pharmaceuticals and personal care products (PPCPs) include a wide range of chemicals such as prescription and over-the-counter drugs, fragrances, diagnostic agents, and a litany of other compounds commonly added to household products such as sunscreens, soaps, toothpastes, and deodorants. If present in natural waters, PPCPs can come into contact with disinfectants during drinking water treatment processes. PPCPs are already known to form a variety of disinfection byproducts (DBPs) when oxidized by free chlorine, including trihalomethanes (THMs) and haloacetic acids (HAAs), many of which are known carcinogens. Salts, such as iodide, are also often present in natural water systems. Iodide is known to form a much more reactive oxidant, free iodine, when it reacts with free chlorine. Free iodine can react with organic compounds in waters to form iodinated byproducts, many of which have been shown to form in higher yields and to be more toxic than their chlorinated analogues. For this reason, it is necessary to more fully understand the fate of PPCPs during drinking water processes. The overall goals of this study are to 1) elucidate reaction mechanisms and product formation potentials for PPCP oxidation by free chlorine in the presence of iodide and 2) develop a computer model that can act as a predictive tool to aid in the assessment of potential risks resulting from PPCPs in source waters. Through the course of this research, a model was developed that could fit reaction rate parameters and accurately predict solution reactivity for a range of substituted phenols as well as PPCPs including bisphenol-A and triclosan. Past studies utilizing pseudo-first-order rate constants to determine a reaction rate over-simplified the analysis of halogen substitution reactions. Free chlorine reaction rate constant values were updated from the literature since the mechanism for electrophilic substitution was found to be different than stated in currently published literature. The involvement of H₂OCl⁺ was found to be negligible. The mechanism for the electrophilic substitution of phenolic compounds by free iodide was also different from current literature findings. We found that I₂, rather than H₂OI⁺, was an extremely important species for free iodine reactions and must be considered when analyzing the reaction kinetics. Finally, we found that small amounts of iodide can significantly affect product formation pathways thereby causing preferential formation of iodinated products and a potential increase in the total product formation. In general, the reaction kinetics were highly dependent upon the pH, iodide to free chlorine ratio, and the reactivity of the phenolic compound, and our model was able to successfully address changes in each of these variables. An LFER was developed that showed a linear relationship between reaction rates and the pK<sub>a</sub> of a phenolic compound. It is believed that the model developed can be used as a predictive tool to estimate reactivity of natural waters for a range of phenolic PPCPs simply by using the compounds pK<sub>a</sub>. / Ph. D.
4

Pharmaceuticals, Personal Care Products, Illicit Drugs and Their Metabolites in Screened Municipal Wastewaters

Lowe, Christopher James 27 September 2013 (has links)
Two characterization studies were undertaken to assess the concentrations and environmental loadings of 125 pharmaceuticals, personal care products, illicit drugs and their metabolites (PPCPs) in screened municipal wastewaters being discharged into Juan de Fuca Strait from two marine outfalls in the Capital Regional District, British Columbia, Canada. Two up-stream pump stations were also sampled. The PPCP concentration profiles were generally similar between the four sampling locations. Qualitative seasonal patterns in PPCP concentrations were also observed, primarily due to rainfall events that diluted wastewater contaminants during the winter. Increases in wastewater flow volumes following a rain event appeared to result in consistent shifts in PPCP concentration profiles for at least three of the four sites. Results indicated that the concentrations of PPCPs were similar to those observed in influents from other jurisdictions. Predicted environmental concentrations were predominantly well below literature concentration thresholds known to induce acute or chronic effects in organisms in the environment. However, there was slight potential for adverse chronic effects as a result of the predicted environmental concentrations of ibuprofen around the outfalls based on comparison to literature environmental effects thresholds. In general, sub-lethal and chronic effects endpoints were relatively limited in availability in the literature, as were literature thresholds derived from exposures to PPCP mixtures. Additional adverse chronic effects of these substances may be discovered in the future. Comparisons were made to regional prescription rates and population demographics to determine whether these factors could be good predictors of PPCP concentrations or loadings. Although wastewater concentrations and loadings were proportional to both prescription rates and population size, the regression relationships were statistically weak or insignificant. As such, prescription rates and population size could not be used to accurately predict pharmaceutical wastewater concentrations and loadings on their own. No qualitative relationships were observed between wastewater PPCP concentrations and either population age or gender breakdown. Overall, wastewater flow volumes, derived population equivalents and analytical method variability were also important factors to consider. Minor proportional deviations were observed following a preliminary loading comparison based on the relative population equivalent sizes of each of the four wastewater system catchment areas. These deviations could have been a result of disproportional hospital loading inputs and/or wastewater system inflow and infiltration. Comparisons were also made between the concentrations of PPCPs and the concentrations of conventional wastewater parameters typically used to characterize bulk wastewater loadings (i.e., carbonaceous biochemical oxygen demand, biological oxygen demand, total suspended solids, volatile suspended solids). Only 18 of the 125 PPCPs were positively correlated with all four conventional parameters. This suggests that designing and optimizing treatment plants to efficiently reduce conventional parameter loadings may not lead to as efficient or consistent reductions in the concentrations of all of the assessed PPCPs. However, the PPCP results were based on analyses of the filtered aqueous fraction of the wastewater samples, whereas the conventional parameter results were based on whole unfiltered effluent samples. As such, there was no direct link between the two sets of results. / Graduate / 0306
5

Sonochemical Degradation of Pharmaceuticals and Personal Care Products

Xiao, Ruiyang 26 June 2012 (has links)
No description available.
6

PERFLUOROALKYL ACIDS AND OTHER TRACE ORGANICS IN WASTEDERIVED ORGANIC PRODUCTS: OCCURRENCE, LEACHABILITY, AND PLANT UPTAKE

Rooney Kim Lazcano (7038074) 14 August 2019 (has links)
<p>Waste-derived organic products are nutrient-rich materials often applied to agricultural land as a fertilizer to enhance agricultural production and soil quality. Commercially available biosolid-based products, which are sold and distributed in bags or bulk, are rapidly gaining popularity for urban and suburban use. Although biosolid-derived products have many benefits, they may contain trace organic contaminants such as per- and polyfluoroalkyl acids (PFAAs) and pharmaceutical and personal care products (PPCPs), in varying levels, depending on waste source composition. These organic compounds have been used in a variety of consumer and industrial products and are known to accumulate in biosolids due to their recalcitrance in conventional wastewater treatment processes. Thus, the application of commercially available biosolids-based products on urban and suburban gardens may lead to transfer and accumulation of organic contaminants into food crops, raising food safety concerns. Most studies to date have focused on municipal biosolids application on agricultural lands with very few studies focused on commercial products available for home and urban gardens. For the latter, the evaluations of bioavailability and subsequent plant uptake of organic contaminants from biosolids have also often been conducted by adding organic contaminants to the growing media (e.g., soil or hydroponic) at a concentration that greatly exceed environmentally relevant concentrations. Moreover, there are currently no studies evaluating leaching and plant uptake potential of contaminants from commercially available (e.g., local stores) biosolids. The research described in this dissertation 1) assessed the occurrence of PFAAs and representative PPCPs in commercially available biosolid-based products and their porewater concentrations in saturated media as a measure of bioavailability and leachability; 2) investigated how heat-treatment, composting, blending and thermal hydrolysis processes on biosolids to convert them to commercial biosolid-based products affect PFAA concentrations in the production of commercial biosolid-based product; and 3) assessed the bioavailability and plant uptake of PFAAs and targeted PPCPs by kale and turnips grown in soil-less potting media amended with Milorganite (a commercially available biosolids-based fertilizer product) at the recommended rate and four times the recommended rate.</p><p>The biosolid-based products displayed varying levels of organic contaminants. Higher PFAA concentrations were detected in biosolid-based products compared to nonbiosolid-based products. The common treatment processes used in taking biosolids to commercially available products were ineffective in reducing PFAA levels in the products except for blending with other essentially PFAA-free materials, thus served as a simple dilution. Porewater concentrations of PFAAs and PPCPs as an indicator of leachability and bioavailability were higher for the less hydrophobic compounds (e.g., short-chain PFAAs and diphenhydramine and carbamazepine with lower octanol-water partition coefficient). Leachability alone did not explain the observed plant uptake potential of PFAAs and PPCPs. With similar leachability and molecular weight/size between diphenhydramine and carbamazepine, higher uptake was observed with a positively charged compound (diphenhydramine compared to a neutral compound (carbamazepine). However, not all positively charged compounds were taken up by the plant. Azithromycin, a positively charged compound, had lower uptake than other contaminants which may be due to its large molecular size compared to diphenhydramine. Higher concentrations of miconazole, triclosan, and triclocarban were found in the biosolids-fertilizer; however, these compounds had low leachabilities and limited uptake by plants. Also, for PPCPs, the application rates of biosolid-based products did not necessarily correlate with the higher uptake and translocation of contaminants to the above-ground portion of plants. </p><p>This study provides an evaluation of commercially available waste-derived organic products under condition comparable to home and urban garden setting. Although biosolids-based products can serve as alternatives to synthetic fertilizers, they contain higher levels of trace organic contaminants than nonbiosolid-organic products. Common biosolids treatment processes are ineffective for reducing the levels of trace organic contaminants in biosolids, particularly for PFAAs. Thus, it is critical to control the sources contributing to the higher level of these contaminants in biosolids-based products. Also, regulations (e.g., triclosan and triclocarban) and replacements (e.g., longer-chain PFAAs to short-chain PFAAs) of persistent trace organic chemicals have led to a reduction in their levels in biosolids-based products. Although longer chain PFAAs are more likely to bioaccumulate and persistent than the replacement short-chain alternatives, the current study has shown that the short-chain PFAAs are more readily taken up to edible parts of plants than longer-chain PFAAs even when applying at the recommended fertilizer rate. Thus, the current movement to replace longer chain PFAAs with short chains has the potential to result in higher total PFAA concentrations being bioavailable for plant uptake, thus increasing the risk of food contamination by PFAAs. </p>
7

The occurrence of the pharmaceuticals and personal care products (PPCPs) and illicit drugs in western Hengchun Peninsula and Kenting tourist area of Taiwan

Tu, Bo-Wen 26 September 2012 (has links)
This study investigated the spatial distribution and seasonal variation of pharmaceuticals and personal care products (PPCPs) and illicit drugs in western Hengchun peninsula and Kenting coastal tourist area in Taiwan. We used solid phase extraction (SPE) followed by liquid-chromatography tandem mass spectrometry (HPLC-MS/MS) to determine 22 PPCPs and 10 illicit drugs in water samples. The detected concentrations of PPCPs and illicit drugs ranged from below detection limit to 9350 ng/L, and the most frequently five detected compounds in this area were ampicillin (79%), codeine (63%), caffeine (62%), carbamazepine (61%) and pseudoephedrine (57%). The impact of the special event- Kenting music festival, such as ¡§spring scream¡¨ was also discussed in this study, and the results from PCA and HCA both showed that the concentrations and distributions of PPCPs and illicit drugs were affected by the tourists. In addition, two wastewater treatments plants (WWTPs) were also investigated for seven days during Kenting music festival period. The results indicated that WWTPs did not show enough removal efficiencies in Kenting tourist area during the special event. The impact of the PPCPs and illicit drugs to the aquatic environment and ecology still needs to be further monitored.
8

Applicability of UV-based and O3-based Processes for the Reduction of Pharmaceuticals and Personal Care Products(PPCPs) / PPCPsの除去のための紫外線、オゾンおよび促進酸化処理の適用性に関する研究 / PPCPs ノ ジョキョ ノ タメ ノ シガイセン オゾン オヨビ ソクシン サンカ ショリ ノ テキヨウセイ ニ カンスル ケンキュウ

Kim, Ilho 24 September 2008 (has links)
Kyoto University (京都大学) / 0048 / 新制・課程博士 / 博士(工学) / 甲第14146号 / 工博第2980号 / 新制||工||1442(附属図書館) / 26452 / UT51-2008-N463 / 京都大学大学院工学研究科都市環境工学専攻 / (主査)教授 田中 宏明, 教授 津野 洋, 教授 清水 芳久 / 学位規則第4条第1項該当
9

Assessment of the Occurrence and Potential Effects of Pharmaceuticals and Personal Care Products in South Florida Waters and Sediments

Wang, Chengtao 18 July 2012 (has links)
A LLE-GC-MS method was developed to detect PPCPs in surface water samples from Big Cypress National Park, Everglades National Park and Biscayne National Park in South Florida. The most frequently found PPCPs were caffeine, DEET and triclosan with detected maximum concentration of 169 ng/L, 27.9 ng/L and 10.9 ng/L, respectively. The detection frequencies of hormones were less than PPCPs. Detected maximal concentrations of estrone, 17β-estradiol, coprostan-3-ol, coprostane and coprostan-3-one were 5.98 ng/L, 3.34 ng/L, 16.5 ng/L, 13.5 ng/L and 6.79 ng/L, respectively. An ASE-SPE-GC-MS method was developed and applied to the analysis of the sediment and soil area where reclaimed water was used for irrigation. Most analytes were below detection limits, even though some of analytes were detected in the reclaimed water at relatively high concentrations corroborating the fact that PPCPs do not significantly partition to mineral phases. An online SPE-HPLC-APPI-MS/MS method and an online SPE-HPLC-HESI-MS/MS method were developed to analyze reclaimed water and drinking water samples. In the reclaimed water study, reclaimed water samples were collected from the sprinkler for a year-long period at Florida International University Biscayne Bay Campus, where reclaimed water was reused for irrigation. Analysis results showed that several analytes were continuously detected in all reclaimed water samples. Coprostanol, bisphenol A and DEET’s maximum concentration exceeded 10 µg/L (ppb). The four most frequently detected compounds were diphenhydramine (100%), DEET (98%), atenolol (98%) and carbamazepine (96%). In the study of drinking water, 54 tap water samples were collected from the Miami-Dade area. The maximum concentrations of salicylic acid, ibuprofen and DEET were 521 ng/L, 301 ng/L and 290 ng/L, respectively. The three most frequently detected compounds were DEET (93%), carbamazepine (43%) and salicylic acid (37%), respectively. Because the source of drinking water in Miami-Dade County is the relatively pristine Biscayne aquifer, these findings suggest the presence of wastewater intrusions into the delivery system or the onset of direct influence of surface waters into the shallow aquifer.
10

Removal Characteristics and Predictive Model of Pharmaceutical and Personal Care Products (PPCPs) in Membrane Bioreactor (MBR) Process / 膜分離活性汚泥法における残留医薬品類の除去特性と予測モデルの開発

Junwon, Park 23 September 2016 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第19984号 / 工博第4228号 / 新制||工||1654(附属図書館) / 33080 / 京都大学大学院工学研究科都市環境工学専攻 / (主査)教授 田中 宏明, 教授 米田 稔, 講師 山下 尚之 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM

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