Darbo tikslas yra įvertinti Raseinių rajono savivaldybės nuotekų sukeliamą taršą ir priemones jai mažinti. Raseinių rajone gyvena 43,7 tūkst. gyventojų, iš kurių apie 79 % prisijungę prie geriamojo vandens tiekimo ir apie 64 % - prie nuotekų šalinimo sistemos. Kiti individualūs gyventojai turi įsirengę vietinius nuotekų sukauptuvus arba turi vietinius nuotekų valymo įrenginius. Dėl blogos sukauptuvų priežiūros dažnai įvyksta persiliejimai, ir nevalytos nuotekos patenka į aplinką. Prieš 30-40 metų įrengtos centralizuotos nuotekų šalinimo sistemos rajone yra susidėvėjusios, todėl jose neišvengiama avarijų. Siekiant sumažinti avarijų, taršos židinių skaičių, būtina rekonstruoti senus vamzdynus, išplėsti nuotekų surinkimo tinklą, prijungiant kuo daugiau gyventojų prie centrinės nuotekų šalinimo sistemos. Vandentvarkos ūkio renovacija ir plėtra Raseinių rajone vykdoma Europos Sąjungos (ES) fondų, Lietuvos ir savivaldybės biudžetų lėšomis. Darbe nagrinėjama vandentvarkos ūkio būklė, ES fondų, Lietuvos ir Raseinių savivaldybės biudžeto remiamų priemonių įtaka aplinkosaugos būklei. / The purpose of this work is to evaluate the wastewater pollution in Raseiniai district and to sugest means to reduce it. Raseiniai district has a population of 43,7 thousand people. 79% of them are connected to the centralized drinking water system, and 64% of them use wastewater disposal system. The remaining individual householders usually use their own wastewater tanks or their local wastewater treatment equipment. Because of the poor wastewater system condition there are the leaks of wastewater to the environment. Since the wastewater treatment systems are 20 – 30 years old, a lot of happening accidents are inevitable. The old pipeline must be renovated in order to decrease the number of accidents and the sources of waste. In addition, more householders should be connected to the centralized wastewater system. The renovation and expansion of the Water – treatment network is financed from the budget of Raseiniai local administration, the structural funds of European Union(EU), and the Cohesion fund. The work includes the inspection of the current state of water-treatment network in Raseiniai district also the influence of the EU structural funds and other means which are used to improve the state of the environment.

Less than 10% of the world’s domestic wastewater is disinfected prior to discharge into surface waters; therefore, human exposure to diverse wastewater-related pathogens results in millions of cases of illness each year. Among the enteric pathogens, viruses represent an important group of emerging pathogens and are frequently the cause of food- and water-borne outbreaks of illness. Although the World Health Organization and many government agencies mandate the use of bacterial indicators to identify poor microbial water quality, it is well known that these indicators poorly correlate with fecal pollution contamination events and risk of disease. The field of public health-related environmental microbiology has made significant advances over the last twenty years; however, there is still a need for improved methods to identify poor microbial water quality and manage health risks associated with water-related activities (e.g., recreation, shellfish harvesting, irrigation). Furthermore, it is imperative to effectively detect fecal pollution in the environment as well as determine the extent of pathogen removal during (waste)water treatment to meet the Sustainable Development Goals associated with water and food security as well as the water reuse recommendations by the U.S. National Research Council. This dissertation directly addressed the need to identify an improved viral indicator by exploring the application of pepper mild mottle virus (PMMoV), a virus of dietary origin that is extremely abundant in human feces, as a surrogate for enteric viruses in diverse settings and contexts. Using a reverse transcription quantitative polymerase chain reaction (RT-qPCR) method, PMMoV was compared with other indicators, index surrogates, and reference pathogens for assessing surface water quality in a developed country (Appendix A) and developing country context (Appendix B and C). In addition, the applicability of PMMoV as a (waste)water treatment process indicator was demonstrated in natural treatment systems in developing countries (Appendix C and D) and artificial treatment systems (Appendix E). In all settings, PMMoV always co-occurred with at least one reference pathogen, index organism, and/or indicator; additionally, PMMoV was detected more frequently and in higher concentrations than other reference pathogens and indicators. Three investigations also associated PMMoV detection with predicted human health risks greater than the health benchmark for recreation and water reuse activities (Appendix A, C, and D). Additionally, PMMoV facilitated an improved understanding of virus-particle interactions in wastewater treatment pond systems (Appendix D) and allowed for an improved understanding of virus removal with respect to riverbank filtration systems and wastewater reuse in agriculture (Appendix C). PMMoV was established as a valuable component of the microbial source tracking toolbox in Costa Rica (Appendix B) and appeared to be useful in Bolivia (Appendix C). Finally, a paradigm shift in (waste)water management is occurring, in which routine monitoring is being replaced by a more holistic approach that includes sanitary surveys, targeted water quality monitoring, and exploratory quantitative microbial risk assessment. To support and complement this paradigm shift, field-based, laboratory-free methods are needed to identify and/or infer the presence of enteric viruses (Appendix F). Collectively, all the investigations presented here confirm the use of PMMoV as a surrogate for enteric viruses; however, its utility depends on the context and research question.

Content: Leather manufacturing industry uses a lot of water and chemicals, and it discharges large amounts of wastewater. The processing a large amounts of wastewater requires a huge cost. Therefore, reduction of amount of a pollution load in wastewater is a theme in many countries around the world. During the leather process, a lot of pollutants occur in the unhairing process. Some estimate that the amount of pollution generated in the unhairing process accounts for 70% of the entire leather manufacturing process. In this unhairing process, usually a large amount of sulfide is used. Sulfide is known to generate hydrogen sulfide and cause damage to the drain pipe. In Tokyo, strict criteria are set for draining sulfide to sewers. Therefore, reducing the amount of sulfide used is an important task for tanner. In addition, since sulfide has no degreasing effect, a large amount of surfactant is required in the unhairing process. However, to reduce the cost and the load of the wastewater, it is also required to reduce the amount of the surfactant used. Furthermore, in recent years, the types of usable surfactants have also been limited. Therefore, development of a method of effectively removing hair loss and degreasing without using a sulfide is urgent for the leather manufacturing industry. On the other hand, pelts are widely used as raw materials for foods such as gelatin and collagen casing, cosmetics, and pharmaceuticals. However, sulfides are not originally recognized as food additives. Therefore, some companies are concerned about using pelts as a raw material for food using sulfide in the unhairing process. Also from this point of view, it is necessary to develop an unhairing method without using sulfides. The method using sodium hydroxide has been studied for a long time. However, this method is hard in handling, and is difficult to set conditions such as concentration and temperature. That is, while successful at the experimental level, it has not been put to practical use. Therefore, we studied a method to solve the above problem using sodium hydroxide. The method developed this time can reduce the pollutant in waste water, and the amount of water used in the unhairing process to 1/10 or less of the conventional one. Moreover, since it is not influenced by water temperature, it made it possible to stably remove hair irrespective of the season. The finished leather kept sufficient strength. In addition, sodium hydroxide reacts with fat in the skin and turns it into soap, so it shows the degreasing effect and contributes to reduce the dosage of degreasing agent. Take-Away: development of unhairing method without using sulfide contributes to reduce the dosage of degreasing agent reduce the pollutant in waste water