MESCH / Department of Hydrology and Water Resources

Occurrence, accumulation and subsequent fate of pharmaceuticals in environment currently represent a very actual topic. Worldwide, thousands of tons of pharmaceutical substances are consumed every year. A large portion of pharmaceuticals is, in unchanged or metabolized forms, disposed via sewage systems and wastewater treatment plants. Considering the fact that wastewater treatment processes are not able to completely eliminate all active substances or their metabolites, pharmaceuticals are systematically washing out into the water system and increasingly contaminate the ground and surface waters. The problematics of continuous control and progressive elimination of pharmaceutical residues from environment are still not completely solved. Thus, the development and availability of accurate and fast commercial analyses are highly desired. The aim of this diploma thesis was the optimization and validation of multi-residue UHPLC- MS/MS analytical method designated for the determination of 52 pharmaceuticals in drinking and waste waters. The work was carried out in laboratories of ALS Czech Republic. An analytical method was subsequently used for monitoring of pharmaceuticals in both drinking and waste waters, as well as for the determination of efficiency of removing these compounds within the...

Water crises are predicted to be amongst the risks of highest concern for the next ten years, due to availability, accessibility, quality and management issues. Knowledge of the microbial communities indigenous to drinking water is essential for treatment and distribution process control, risk assessment and infrastructure design. Drinking water distribution systems (DWDSs) ideally should deliver to the consumer water of the same microbial quality as that leaving a treatment plant (“biologically stable” according to WHO). At the start of this Ph.D. program water microbiology comprised conventional culturedependent methods, and no studies were available on microbial communities from source to tap. A method combining 16S rRNA gene pyrosequencing with flow cytometry was developed to accurately detect, characterize, and enumerate the microorganisms found in a water sample. Studies were conducted in seven fullscale Dutch DWDSs which transport low-AOC water without disinfectant residuals, produced from fresh water applying conventional treatment. Full-scale studies were also conducted at the desalination plant and DWDS of KAUST, Saudi Arabia where drinking water is produced from seawater applying RO membrane treatment and then transported with chlorine residual. Furthermore, biological stability was evaluated in a wastewater reuse application in the Netherlands. When low-AOC water was distributed without disinfectant residuals, greater bacterial richness was detected in the networks, however, temporal and spatial variations in the bacterial community were insignificant and a substantial fraction of the microbiome was still shared between the treated and transported water. This shared fraction was lower in the system transporting water with chlorine residual, where the eukaryotic community changed with residence time. The core microbiome was characterized and dominant members varied between the two systems. Biofilm and deposit-associated communities were found to drive tap water microbiology regardless of water source and treatment scheme. Network flushing was found to be a simple method to assess water microbiology. Biological stability was not associated with safety. The biological stability concept needs to be revised and quantified. Further research is needed to understand microbial functions and processes, how water communities affect the human microbiome, and what the “drinking” water microbiome is like in undeveloped countries. / The research presented in this doctoral dissertation was financially supported by and conducted in collaboration with Delft University of Technology (TU Delft) and Evides Waterbedrijf in the Netherlands.

<p>This dissertation investigates the factors which affect the removal of arsenic from groundwater by adsorption and coagulation technologies, including the interactions between As and natural organic matter (NOM). Humic acid (HA) was utilised as an NOM analogue, and was shown to be capable of both complexing and oxidising As, depending upon the prevailing conditions. The arsenic removing capabilities of three iron oxide coated sands (IOCS) were investigated, including IOCSW, a waste material from a local drinking water treatment plant generated during the removal of iron and manganese. IOCSW was highly effective at removing both As(V) and As(III) from synthetic water matrices (qmax = 78.3 &micro;g As(V)/g and 99.1 &micro;g As(III)/g). The negative effects of competitive anions (phosphates, silicates and HA) on arsenic removals were not significant enough to preclude the application of IOCSW for arsenic removal during drinking water treatment. The removals of both As and NOM by coagulation and enhanced coagulation with pH correction and preoxidation were also investigated. As(V) &nbsp;was more readily removed by coagulation than As(III), so that the most efficient coagulation treatment investigated for arsenic and NOM removal applied preozonation with subsequent combined coagulation with polyaluminium chloride and ferric chloride. Different groundwaters displayed large variations in the As and NOM removal behaviours. Response surface methodology (RSM) was therefore applied to investigate &nbsp;the interactions between As and NOM during ferric chloride coagulation and optimise their combined removals. Multiple interaction effects were observed during this investigation, highlighting the importance of utilizing RSM to optimise drinking water treatment technologies.</p> / <p>Ova disertacija ispituje faktore koji utiču na uklanjanje arsena iz podzemne vode primenom adsorpcija i koagulacije, uključujući i interakcije između arsena i prirodnih organskih materija (POM). Huminska kiselina (HA) je korisćena kao model za POM, a pokazano je da može i da kompleksira i da oksiduje As, u zavisnosti od eksperimentalnih uslova. Ispitivane su mogućnosti uklanjanja arsena za tri peska obložena gvožđe oksidom (IOCS), uključujući IOCSW, koji je dobijen sa postrojenja za tretman vode za piće i potiče iz procesa uklanjanja gvožđa i mangana. IOCSW se pokazao kao visoko efikasan za uklanjanje As(V) i As(III) iz sintetičkih vodenih matriksa (q_max = 78.3 &micro;g As(V)/g i 99.1 &micro;g As(III)/g). Negativni efekti kompetirajućih jona (fosfata, silikata i HA) na uklanjanje arsena nisu bili dovoljno značajni da bi se isključila primena IOCSW za uklanjanje arsena tokom tretmana vode za piće. Zajedničko uklanjanje As i POM koagulacijom i unapređenom koagulacijom uz pode&scaron;avanje pH i kombinovanje sa oksidacionim predtretmanima je takođe ispitivano. Bolje uklanjanje koagulacijom postignuto je za As(V) u odnosu na As(III), stoga se kao najefikasniji ispitivani koagulacioni tretman pokazalo uklanjanje arsena i POM primenom predozonizacije praćene kombinovanom koagulacijom sa polialuminijum hloridom i gvožđe hloridom. Ispitivanja na različitim podzemnim vodama, pokazala su velike varijacije u pona&scaron;anju As i POM tokom tretmana. Iz tog razloga je primenjena metodologija odzivne povr&scaron;ine (RSM) u cilju ispitivanja interakcija između As i POM tokom koagulacije gvožđe hloridom i optimizacije njihovog kombinovanog uklanjanja. Sagledavanje većeg broja interakcija primenom metodologije odzivne povr&scaron;ine potvrđuje važnost njegove primene pri optimizaciji tretmana vode za piće.</p>

The Council Directive 98/83/EC of 3 November 1998 on the quality of water intended for human consumption was released to ensure the quality of the drinking water within the European Union (EU). Since the directive got introduced the amount of chemicals has significantly increased. The purpose of this thesis is therefore to study how the chemicals are managed within the management of the drinking water in Stockholm to get an insight into different interactions within the science-policy sphere and how it creates obstacles in the improvements of the drinking water quality. A case study with qualitative interviews was made with people active in different levels of the drinking water management, including the research field. The result of the study identifies three areas where obstacles occurred. Through the theoretical framework for science-policy that include eight delay mechanisms an analyze of the existing obstacles in the management was made to identify if any of these eight occurs. The first obstacle is within communication where it shows that knowledge can be communicated more effectively between the concerned authorities. The delay mechanisms within the category that can be identified is science denial, scientific controversy, scientific uncertainty, science-based advice, decision thresholds, unclear goals and norms and implementation deficits. The second obstacle is within uncertainties in who bear the responsibility and where the delay mechanisms that can be identified is science denial, scientific uncertainty, policy formulation, decision thresholds, unclear goals and norms and implementation deficits. The third obstacle is the distribution of the financial resources where there are difficulties and an uneven distribution between municipalities of different sizes. The occurring delay mechanism that can be identified in this obstacle is scientific uncertainty, unclear goals and norms, decision thresholds and implementation deficits. / För att säkerställa dricksvattenkvaliteten inom Europeiska Unionen (EU) uppkom Europaparlamentets och rådets direktiv 98/83/EG av den 3 november 1998 om kvaliteten på dricksvatten. Sedan direktivet infördes har antalet kemikalier ökat markant. Syftet med studien är därför att undersöka hanteringen av kemikalier i Stockholms dricksvattenförvaltning för att få en insyn i hur olika interaktioner inom sciencepolicysfärerna skapar hinder i förbättring av dricksvattenkvaliteten. En fallstudie har genomförts med kvalitativa intervjuer där personer från olika nivåer inom förvaltningen har intervjuats vilket även innefattar forskningsområdet. Utifrån resultatet har tre områden identifierats där hinder förekommer. Genom det teoretiska ramverket för science-policy som innefattar åtta stycken fördröjningsmekanismer utfördes en analys av de förekommande hindren i förvaltningen för att identifiera om några av dessa åtta förekommer. Det första hindret är inom kommunikation där det framkommer att kunskap kan förmedlas mer effektivt mellan de berörda instanserna. Fördröjningsmekanismerna som förekommer inom hindret är vetenskapsförnekelse, vetenskapliga kontroverser, vetenskaplig osäkerhet, vetenskapsbaserad rådgivning, beslutströsklar, otydliga mål och normer och implementeringssvårigheter. Nästa identifierade hinder är inom ansvar. De fördröjningsmekanismer som förekommer inom hindret är vetenskapsförnekelse, vetenskaplig osäkerhet, policyformulering, beslutströsklar, otydliga mål och normer och implementeringssvårigheter. Det sista hindret är inom resurser där det finns svårigheter med att få finansiering till förbättring och att de är ojämnt fördelade mellan kommuner med olika storlek. Fördröjningsmekanismerna som förekommer inom hindret är vetenskaplig osäkerhet, otydligt formulerade mål och normer, beslutströsklar och implementeringssvårigheter.

This project seeks to assess the impact of the sachet water industry on the health, socio-economic and the environmental situation of the inhabitants of Accra, the capital city of Ghana. In addressing the situation, the driving forces which have fuelled the shift of consum-er taste from the normal tap water and the traditional hand-tied-ice water products to the plastic sachet water (commonly known in as "Pure Water") are identified. Lack of access to continuous flow of improved water and the perceived poor quality of the urban water supply system as results of poor management structure are identified as some of the factors for the shift in consumers’ taste for plastic sachet and bottled drinking water. The quality of the plastic sachet is also assessed through the review of previous research results. These are confirmed by laboratory analysis of about six brands of plastic sachet water and two brands bottled drinking water. The laboratory analysis carried out assessed the microbial, physical and chemical quality of the various samples. To assess the health impacts of the products, the results from the analysis are compared with WHO guideline values and other international guideline values. Questionnaires are also administered to ascertain the socio-economic impacts of the products on the life of the young men and women as well sachet water manufacturers. From this, some measures are suggested as to how to mitigate the activities of the sachet water business to reduce its negative effects on the health, the environment and the socio-economic status of the inhabitants of the city.

In Virginia, over one million households rely on private water supplies (e.g. well, spring, cistern). Previous literature acknowledges bacterial contamination in private water supplies as a significant public health concern in the United States. The present study tested private wells and springs in 20 Virginia counties for total coliforms (TC) and E. coli (EC) along with a suite of chemical contaminants. Sample collection was organized by the Virginia Household Water Quality Program (VAHWQP), a Virginia Cooperative Extension effort managed by faculty in the Biological Systems Engineering Department. Microbial and chemical source tracking were used to identify possible sources of contamination. A logistic regression was employed to investigate potential correlations between TC contamination and chemical parameters (e.g. NO3-, turbidity) as well as homeowner provided survey data describing system characteristics and perceived water quality. TC and EC contamination were quantified via the Colilert (www.idexx.com) defined substrate method for most probable number (MPN) of EC and TC per 100 mL of water. Of the 538 samples collected, 41% (n=221) were positive for TC and 10% (n=53) for EC. Chemical parameters were not statistically predictive of microbial contamination. Well depth, water treatment, and farm location proximate to the water supply were factors in a regression model that predicted presence/absence of TC with 74% accuracy. Microbial and chemical source tracking techniques (Polymerase Chain Reaction (PCR) and fluorometry, respectively) identified 4 of 26 samples as likely contaminated with human wastewater. Application of these source-tracking analyses on a larger scale will prove useful in defining remediation strategies. / Master of Science

As climate change progresses, the number of extreme weather events are predicted to rise and generate an increase in climate related humanitarian emergencies. These emergencies result in complex displacements of populations, unsanitary conditions, and a corresponding increase in diarrheal disease risks within affected communities. Because diarrheal disease ranks as one of the major contributors to overall morbidity and mortality rates following a disaster, it is critically important that aid agencies are prepared to make informed decisions regarding the prevention of disease transmission. As water is one of the main transmission routes of diarrheal disease, providing clean and safe drinking water is acknowledged as one of the most important and effective interventions. Once we acknowledge the importance of this resource, we also acknowledge the need for quick, simple, and effective water treatment solutions. The term point-of-use (POU) water treatment defines water treatment systems and technologies that are used at the point of consumption. These systems often treat relatively small batches of water and are operated by the consumer or head of household. POU water treatment systems and safe storage techniques have been shown to improve water quality and decrease diarrheal disease incidence and are therefore an effective option in humanitarian emergencies. One type of POU water treatment product - coagulant/disinfection products (CDPs) which are also known as flocculant/disinfectants, have been increasingly used in response to humanitarian emergencies. CDPs are shown to provide microbial and aesthetic (i.e. turbidity reductions) water quality improvements and post-treatment protective free chlorine residuals (FCRs). The relative simplicity of CDPs allows quick intervention for communities with few resources plus CDPs are durable, small, and ready for quick deployment. However, limited research has been completed on the different CDPs on the market or on methods to improve them. This thesis explores CDPs and their role in emergency response through two interlinked perspectives: 1. First, in an overall review compiled as Manuscript #1 (Chapter 2), I assess the existing and current CDPs, how they perform in comparison to global water treatment guidelines, and where their limitations lie. The outcomes of this study provide a simple analysis for aid agencies to carefully select the CDPs used in emergency interventions; and 2. I take the findings from the research completed in Chapter 2 to develop a computational modelling approach to improving the residual protective capacity of the CDPs. These results are presented in Manuscript #2 (Chapter 3) . The outcomes are intended to serve two purposes: (1) to provide a baseline computational model to guide and encourage improvement and testing of these products by manufacturers; and (2) to provide an educational tool to facilitate understanding of these products and the key functions taking place during their treatment. This thesis addressed the research objective of invoking conversation surrounding effective emergency response through developing solutions to provide clean drinking water in at-risk communities during complex humanitarian emergencies. / Graduate

Les bactéries sont une composante indissociable des réseaux de distribution d’eau potable qui, en les colonisant, forment des communautés complexes. Il est émis l’hypothèse que des variations de structure et de composition de ce microbiome pourraient refléter des changements de la qualité de l’eau liés à différents phénomènes (stagnation, biocorrosion, changement de pression, ...). Une importante campagne de prélèvements menée sur le réseau d’eau potable de Paris a permis d’apprécier la dynamique de ces communautés bactériennes selon trois méthodes différentes : la description de la communauté par metabarcoding, la culture de la flore hétérotrophe totale et la quantification par PCR de trois pathogènes opportunistes, Mycobacterium spp. L. pneumophila, et P. aeruginosa. Cette étude a mis en évidence une certaine diversité au sein des communautés bactériennes de l’eau potable malgré une prédominance des genres Hyphomicrobium et Phreatobacter. Les méthodes de culture et de PCR quantitative mettent également à jour l’importance écologique du genre Mycobacterium. L’intégration aux analyses des paramètres spatio-temporels et physico-chimiques de l’eau potable a permis de constater une relative stabilité des communautés bactériennes. Cependant, suite à d’importants évènements climatiques, des variations dans la structure des communautés sont visibles sans conséquence sur la qualité sanitaire de l’eau. Ces travaux suggèrent que l’utilisation en parallèle de différentes méthodologies, et notamment l’apport du metabarcoding, permet d’améliorer la connaissance sur le réseau de distribution d’eau potable et de mieux observer des changements fins, invisibles aux méthodes classiques. / Bacteria are an indivisible component of drinking water distribution systems which, by colonizing them, form complex communities. It is assumed that variations in the structure and composition of this microbiome could reflect a change in water quality related to different events (stagnation, biocorrosion, pressure change, etc.). A major sampling campaign was conducted within the Paris drinking water distribution systems allowing to assess the diversity and the dynamic of these bacterial communities using three different methods: description of the community by metabarcoding, heterotrophic plate count and quantification by PCR of three opportunistic pathogens, Mycobacterium spp. L. pneumophila, and P. aeruginosa. This study revealed some diversity within the drinking water bacterial communities. Culture and quantitative PCR methods also reveal the ecological importance of the Mycobacterium genus. The integration of spatio-temporal and physico-chemical parameters of drinking water into analyses has highlighted a relative stability of bacterial communities. However, variations in the structure of the communities are visible following important climatic events, without consequences on the sanitary quality of the water. Altogether, our work suggests that the use in parallel of different methodologies, particularly metabarcoding, has improved our knowledge of the bacterial communities within the Paris drinking water distribution systems and better observe subtle changes, invisible to conventional methods.

As water resources are rapidly being exhausted, more and more interest is focused on the desalination of sea water and brackish water. Increasing amounts of fresh water will be required in the future due to the rise in population rates, increasing living standards and the expansion of industrial and agricultural activities. The thesis is concentrated on current issues of treatment of sea water, mainly the desalination based on the distillation principle, in order to develop a unit for seawater treatment. The aim is to develop a compact modular unit for seawater desalinate on based on the implementation and evaluation of experimental tests on the experimental unit. The solution includes an overview of systems for treatment of seawater, a discussion of structural and material aspects of the units, design and manufacture of the experimental unit and confrontation the calculated values with the results of experimental measurements.