Municipal wastewater treatment has a long history of local handling with recovery of toilet wastes for use in agriculture and to some extent energy recovery from biogas by use of local handling. This may be seen as ―the first way‖ further developed by septic tanks and infiltration and recovery as in Ecological Sanitation and use of urine separation toilets. However, problems related to water borne diseases and odor problems successively gave rise to ―the second way‖ with central wastewater systems with large investments in water and sewer nets and increasingly better technologies for water treatment and wastewater treatment. This technology may treat municipal wastewater to a drinking water quality and recover part of energy and nutrients contents for eco-cycling. The problems noted and which are quite obvious are affordability in poor countries and the need for much energy supply and with negative effects of emission of greenhouse gases. Ways should be better evaluated to obtain both an effluent wastewater of drinking water quality and at the same time be self-sufficient with energy, obtain products with a commercial value and comply with methods to reduce the amounts of released greenhouse gases. It is suggested that an intermediate dehydration step should be used by dividing the main stream into two streams, one to which water has been transferred by methods as forward osmosis or freezing and one remaining concentrated stream that could be treated more efficiently. New technologies should be considered for electricity production as use of fuel cell technology and forward osmosis. Methods to diminish greenhouse gas emissions include avoidance of such redox potentials and process conditions that lead to greenhouse gas emissions and binding of carbon dioxide in algae and plants and in clatharates.

No description available.

Continuous increases in the interest and implementation of wastewater reuse due to intensified water stress has escalated the concerns of emerging contaminants. Among emerging contaminants there are microbial (antibiotic resistance) and chemical (pharmaceuticals) elements which have been shown to survive wastewater treatment. This dissertation aims to mitigate emerging contaminants by means of understanding and/or developing the appropriate disinfection strategies, with the intention to provide knowledge that would facilitate towards safe and sustainable water reuse. The first part of this thesis explored microbial risk component of antibiotic resistance. Antibiotic resistance genes are abundant in treated wastewater, and only pose a risk if taken up by potential pathogens through natural transformation. Our results showed that solar irradiation can double natural transformation rates, mediated by reactive oxygen species generation, which led to upregulation in DNA repair and competence genes in Acinetobacter baylyi ADP1. Treatment with UV-C254 nm irradiation also resulted in upregulation in DNA repair genes, nevertheless we observed a decrease in natural transformation rates. These results imply that direct damage of antibiotic resistance genes (ARG) could inhibit their spread and therefore risk, despite other factors contributing to the contrary. The next chapter in this dissertation postulated that the UV/H2O2 combination would be ideal to treat microbial and chemical emerging contaminants in effluent generated from an anaerobic membrane bioreactor. We demonstrated that at an optimal UV intensity and H2O2 concentration, we were able to achieve a 2 and 6-log reduction of the two antibiotic resistance genes and bacteria and used in this study, respectively, and more than 90% removal of the three pharmaceutical compounds. These observations suggest that UV/H2O2 has great potential in treating effluent with high nitrogen concentrations, preserving the fertilization benefit of AnMBR effluent. Overall, this dissertation revealed the potential of UV-based treatments for treated wastewater intended for reuse. Post-membrane processes effluent allows one to deploy UV-C254 nm to selectively target DNA and therefore ARB and ARG that may be still present in the treated wastewater. At the same time, coupling chemical oxidants with UV-C (i.e., UV AOP) would further enhance the means to simultaneously oxidize and degrade potentially harmful chemical contaminants.

Dans le cadre du présent travail, nous nous intéressons à l'étude de l'impact des conditions hydrodynamiques et des matériaux utilisés sur le développement de biofilm au niveau des conduites des systèmes de micro-irrigation. Cette étude contribue à l'amélioration de la compréhension de l'impact de ces paramètres dans la mise en place et la croissance du biofilm. Pour ceci, un montage expérimental aux conditions d'écoulement maîtrisées a été mis en place au laboratoire avec une eau usée modèle de forte concentration en DCO (200 mg.L-1). Le suivi des paramètres de qualité d'eau (COT et oxygène dissous) ont été réalisés au cours des expérimentations. La masse du biofilm récupéré dans les conduites a été mesurée après un séchage à l'étuve à 105°C pendant 24 heures. Les résultats montrent une cinétique de développement du biofilm dans les conduites et confirment l'influence de l'hydrodynamique sur le développement de biofilm. Trois vitesses d'écoulement ont été testées (0,4, 0,8 et 1,2 m. s-1), le biofilm a tendance à se développer dans les conduites à plus faible vitesse. Une valeur seuil, à partir de laquelle la croissance du biofilm est observée tardivement, a été également identifiée. Les résultats obtenus ont été utilisés pour paramétrer un modèle cinétique simple qui permet de décrire le développement de biofilm en fonction des conditions hydrodynamiques. D'autres expérimentations ont été réalisées en parallèle pour étudier l'impact des matériaux plastiques (PE et PVC) et la configuration des conduites du montage expérimental sur le développement de biofilm. / This work aims to improve our understanding on how these parameters impact biofilm establishment and growth. For this purpose, we carried out an experiment in controlled hydrodynamic conditions using a synthetic effluent (200 mg.L-1 of COD concentration). Some water quality parameters (TOC and dissolved oxygen) were monitored . Moreover, biofilm was removed from pipes and then weighed after drying at 105°C for 24 hours. The obtained results confirmed the influence of hydrodynamic on biofilm development. Three flow rates were tested (0,4 ; 0,8 and 1,2 m.s-1) and it was observed that biofilm tends to develop in pipes at lower velocities. A threshold velocity value, from which biofilm growth was observed later, was also identified. The experimental results were used to build a simple model to describe biofilm development as a function of hydrodynamic conditions. Additionnal experiments were performed to study the impact of plastic materials (PE and PVC) and pipes configuration on biofilm growth

Today billions of people live without access to basic sanitation facilities, and thousands die every week due to diseases caused by fecal contamination associated with improper sanitation. It has thus become crucial for decision makers to have access to relevant and sufficient data to implement appropriate solutions to these problems. The Global Water Pathogen Project http://www.waterpathogens.org/ is dedicated to providing an up-to-date source of data on pathogen reduction associated with different sanitation technologies that are important if the world is to achieve the Sustainable Development Goals (SDGs) related to health and sanitation provision. In this research, a subset of the Global Water Pathogen Project (GWPP) data is used to access the reduction of bacteria and viruses across different mechanical and natural sanitation technologies. The order of expected removal for bacteria during wastewater treatment was reported as highest for a membrane bioreactor (4.4 log10), waste stabilization pond (2.3 log10), conventional activated sludge (1.43 log10), anaerobic anoxic oxic activated sludge (1.9 log10), trickling filter (1.16 log10), and upflow anaerobic sludge blanket reactor (1.2 log10). Furthermore, the order of expected removal for viruses was reported as highest for a membrane bioreactor (3.3 log10), conventional activated sludge (1.84 log10), anaerobic anoxic oxic activated sludge (1.67 log10), waste stabilization pond (1 log10), upflow anaerobic sludge blanket reactor (0.3 log10) and trickling filter (0.29 log10). It was found that hydraulic retention time (HRT) had a statistically significant relation to the reduction of bacteria in an anaerobic, anoxic oxic treatment system. Similarly, a significant relation was found between the number of waste stabilization ponds in series and the expected reduction of bacteria. HRT was also found to be a significant factor in virus reduction in waste stabilization ponds. Additionally, it was observed that waste stabilization ponds, trickling filters, and UASB reactors could obtain a greater reduction in bacteria (5-7 log10) when combined with additional treatment (e.g., chemical disinfection or use of maturation ponds). Also, mechanized systems, such as activated sludge systems and membrane bioreactors, obtained a greater reduction (2-3 log10) of viruses when compared to a natural system. It was concluded that the selection of the best suitable technology for pathogen reduction depends on environmental, design, and operational factors as well as considering the performance of specific wastewater treatment systems individually as well as when combined with other treatment technologies that may provide added removal of microbial constituents.

Submitted by Neusa Fagundes (neusa.fagundes@unioeste.br) on 2018-02-05T18:26:08Z No. of bitstreams: 2 James_ Morais2018.pdf: 2489413 bytes, checksum: 8a6f574d868e585f5e6e2fef836e47fb (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-02-05T18:26:08Z (GMT). No. of bitstreams: 2 James_ Morais2018.pdf: 2489413 bytes, checksum: 8a6f574d868e585f5e6e2fef836e47fb (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2018-07-07 / The processes that take part of poultry slaughter are responsible for a great amount of water consumption and, consequently, a generation of large volumes of wastewater, which are usually disposed on soil without any control of uniformity regarding its distribution. Thus, this study aimed at evaluating a drip irrigation system, applied to dispose treated poultry slaughterhouse effluent on soil, using three effluent application rates of 100, 200 and 300 m³ ha-1 day-1. Besides the irrigation system, the effluent quality was also evaluated according to its physical-chemical characteristics. The evaluation of the results was given by the following coefficients: Christiansen Uniformity (CUC), Uniform Distribution (UDC), the Statistical Uniformity Coefficient (SUC) as well as quality control techniques. This trial was carried out in an eucalyptus reforestation area from the Industrial Poultry Slaughterhouse of Lar Agroindustrial Cooperative, in Matelândia city, PR. According to data obtained in this research, it was concluded that drip irrigation system, using the proposed rates, can be considered adequate, since it has shown uniformity in distribution of flows, pH and electrical conductivity. For pH and electrical conductivity, all the evaluated uniformity coefficients, CUC, UDC and SUC, were estimated in more than 90% and considered excellent. For the flow rates, all the coefficients were estimated as superior to 90% for 100 m³ ha-1 day-1 treatment and above 80% for treatments of 200 and 300 m³ ha-1 day-1. Usually, the distributions showed the highest coefficient of uniformity for the three parameters evaluated in the three studied treatments, for the highest tested rate of application. Regarding the effluent characterization, it was concluded that its main characteristics are the concentrations of nitrogen, phosphorus and carbon. And during the experiment, the industry kept the standards of disposal in the environment, which were determined by the environmental agencies. Finally, it was concluded that the statistical process control is adequate to evaluate the effluents as well as irrigation uniformity in tests area. / Os processos inerentes ao abate de aves respondem por um grande consumo de água e, consequentemente, a geração de grandes volumes de efluentes que, em geral, são dispostos no solo sem qualquer controle de uniformidade sobre a distribuição. Assim, o objetivo deste estudo foi avaliar um sistema de irrigação por gotejamento, aplicado à disposição de efluente tratado de abatedouro de aves no solo, utilizando três taxas de aplicação de efluente: 100, 200 e 300 m³ ha-1 dia-1. Além do sistema de irrigação, a qualidade do efluente também foi avaliada em função das características físico-químicas. A avaliação dos resultados foi dada pelos Coeficientes de Uniformidade de Christiansen (CUC), de Uniformidade de Distribuição (CUD), de Uniformidade Estatístico (CUE), bem como pelas técnicas de controle de qualidade. O experimento foi realizado na área de reflorestamento com eucalipto da Unidade Industrial de Aves da Lar Cooperativa Agroindustrial, em Matelândia, PR. De acordo com os dados obtidos neste trabalho, concluiu-se que o sistema de irrigação por gotejamento, utilizando-se as taxas propostas, pode ser considerado apropriado, pois apresentou uniformidade na distribuição das vazões, do pH e da condutividade elétrica. Para o pH e a condutividade elétrica, todos os coeficientes de uniformidade avaliados, CUC, CUD e CUE, foram estimados em mais de 90%, considerados excelentes. Para as vazões, todos os coeficientes foram estimados acima dos 90% para o tratamento de 100 m³ ha-1 dia-1 e acima dos 80% para os tratamentos de 200 e 300 m³ ha-1 dia-1. Em geral, as distribuições apresentaram maior coeficiente de uniformidade, para os três parâmetros avaliados, nos três tratamentos, para a maior taxa de aplicação testada. Em relação à caracterização do efluente, concluiu-se que suas principais características são as concentrações de nitrogênio, fósforo e carbono. E, durante o experimento, a indústria manteve os padrões de lançamento no ambiente, determinados pelos órgãos ambientais. Por fim, concluiu-se que o controle estatístico de processo é adequado à avaliação, tanto de efluentes quanto de uniformidade na irrigação, em testes a campo.

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.

Made available in DSpace on 2017-07-20T12:40:16Z (GMT). No. of bitstreams: 1 Grasiele Cavallini tese.pdf: 2849739 bytes, checksum: 3a66c1a0f56779dc9b4b25e36a7e4b63 (MD5) Previous issue date: 2015-10-23 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / This study evaluates the use of a pilot filtering double unit, comprising an ascending draining gravel filter and a rapid descending sand filter for the treatment of UASB reactor effluent. As a preliminary phase to the double filtering, coagulation/oxidation was used aiming at helping degradation and flocculation of contaminants, facilitating their retention on the filters. In this phase, three combinations were used: ferrous sulfate (FS) and peracetic acid (APA); ferrous chloride (FC) and CF and APA, all with the same iron concentration. After treatability tests, the efficacy of the system was assessed through the physical-chemical and microbiological parameters. In all treatments carried out in the pilot unit, the suspended solids (SST) were totally removed, which resulted in over 90% turbidity reduction. The treatments in the presence of APA demonstrated higher removal of the effluent color, however, the treatment with FS and APA cannot be recommended due to the high concentration of sulfate ions in the final effluent. Regarding microbiological parameters, the presence of oxidant contributed to the partial inactivation of microorganisms. The alternative to carry out a disinfection phase with APA after double filtering using the coagulant/oxidant FC/APA can be employed without any addition phase to irrigate orchards, pastures and cereal crops according to the NBR 13969/97. By adding the pH adjustment phase and chloride addition to the treatment proposed, the treated effluent can be reused in: agriculture, restrictive agriculture; damming, restrictive damming, environment, industry and the replenishment of underground water (except for drinking purposes), according to the recommendations of the USEPA (2012) Recommendation Manual. / Este trabalho avalia o uso de uma unidade piloto de dupla filtração, composta por filtro de pedregulho de escoamento ascendente e filtro rápido descendente de areia para pós-tratamento de efluente de reator UASB. Como etapa preliminar à dupla filtração utilizou-se a coagulação/oxidação, com o objetivo de auxiliar na degradação e na floculação dos contaminantes, facilitando sua retenção nos filtros. Nesta etapa foram utilizadas três combinações: Sulfato ferroso (SF) e ácido peracético (APA); Cloreto férrico (CF) e CF e APA, todas com a mesma concentração de ferro. Após os ensaios de tratabilidade a eficiência do sistema foi avaliada através de parâmetros físico-químicos e microbiológicos. Em todos os tratamentos realizados na unidade piloto os sólidos em suspensão (SST) foram totalmente removidos o que refletiu em reduções superiores a 90% de turbidez. Os tratamentos com a presença do oxidante APA demonstraram uma remoção maior da cor do efluente, porém o tratamento com SF e APA não pode ser recomendado pela alta concentração de íons sulfato no efluente final. Quanto aos parâmetros microbiológicos, a presença do oxidante contribuiu para a inativação parcial dos microrganismos. A alternativa de realizar a etapa de desinfecção com APA após a dupla filtração com CF também foi avaliada e possibilitou desinfecção total do efluente quanto aos indicadores de contaminação avaliados. Considerando a possibilidade de reúso, o efluente UASB pós-tratado pela dupla filtração utilizando o coagulante/oxidante CF/APA pode ser utilizado sem nenhuma etapa adicional para irrigação de pomares, pastagens e cultivo de cereais de acordo com a NBR 13969/97. Acrescentando a etapa de ajuste de pH e adição de cloro no tratamento proposto o efluente tratado pode ser utilizado para reúsos: agrícola; agrícola restritivo; represamento; represamento restritivo; ambiental; industrial e reabastecimento de águas subterrâneas (reutilização não potável), de acordo com as recomendações do manual de reúso da USEPA (2012).

Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-05-29T14:21:19Z No. of bitstreams: 1 DANILO RODRIGUES MARTINS - DISSERTAÇÃO PPGSA PROFISSIONAL 2018..pdf: 646787 bytes, checksum: 17b1a9fda99ec0a453a01f96019b7935 (MD5) / Made available in DSpace on 2018-05-29T14:21:19Z (GMT). No. of bitstreams: 1 DANILO RODRIGUES MARTINS - DISSERTAÇÃO PPGSA PROFISSIONAL 2018..pdf: 646787 bytes, checksum: 17b1a9fda99ec0a453a01f96019b7935 (MD5) Previous issue date: 2018 / A pesquisa tem por escopo trazer a discussão da necessidade de legislação específica para o reuso de águas residuárias que é uma prática de gestão sustentável dos recursos hídricos. Tendo como principal vantagem a redução da demanda por água potável, mitigando a pressão sobre os mananciais. Assim, tal redução decorre da aplicação das águas de reuso às finalidades que podem ser atendidas por águas com características menos restritivas do que às características exigidas para consumo humano, no viés da tecnologia agroindustrial e industrial. Devido aos riscos tanto à saúde pública quanto ao meio ambiente, decorrentes da prática do reuso de água residuária, o desenvolvimento do uso de tal tecnologia exigirá enérgica intervenção do Estado, na forma da lei, onde existe projeto, sem contudo finalizá-lo. O objetivo desta intervenção será maximizar os benefícios auferidos com a prática e reduzir os malefícios associados à sua gestão. De modo que a presente pesquisa tem como objetivo discutir a normatização da prática do reuso de água residuária no Brasil. As competências legislativas dos entes federativos e casos exitosos desta colmatação. Para tanto, procedeu-se à revisão bibliográfica do conceito de reuso de água, abordando seus tipos e aplicações, elencando, ainda, as finalidades de aplicação das águas de reuso. A revisão bibliográfica também teve como objetivo o levantamento do marco legal do reuso de água no Brasil. A partir do conceito de reuso de água pode ser estabelecida a relação entre a prática do reuso de água e os objetivos preconizados pela Política Nacional de Recursos Hídricos. Deste modo, se fará a pesquisa qualitativa com à utilização de dados no método hipotético-dedutivo observando as normas já existentes e à necessidade de legislação específica, analisando o projeto de Lei Federal sobre o tema e pontuando as especificações necessárias para minúcias, bem como fazendo uma pesquisa exploratório entrevistando atores que estão inseridos nesta necessidade de norma específica, dado o que se observa no entrave burocrático em razão da ausência de legislação específica. / The research aims to bring the discussion of the need for specific legislation for the reuse of wastewater, which is a practice of sustainable management of water resources. With the main advantage being the reduction of the demand for drinking water, mitigating the pressure on the sources. Thus, this reduction results from the application of the reuse water to the purposes that can be served by waters with characteristics less restrictive than the characteristics required for human consumption, in the bias of the agro-industrial technology, that is, use for the production of agricultural inputs. Due to the risks to both public health and the environment arising from the practice of reuse of wastewater, the development of the use of such technology will require vigorous State intervention, in the form of the law, where a project exists, without, however, finalizing it. The objective of this intervention will be to maximize the benefits of the practice and reduce the harm associated with its management. Therefore, the present research aims to discuss the standardization of the practice of wastewater reuse in Brazil. The legislative powers of federative entities and successful cases of this closure. In order to do so, a bibliographic review of the concept of water reuse was carried out, addressing its types and applications, also listing the purposes of reuse water application. The bibliographic review also had as objective the survey of the legal framework of the reuse of water in Brazil. From the concept of water reuse, the relationship between the practice of water reuse and the objectives advocated by the National Water Resources Policy can be established. In this way, qualitative research will be done using data in the hypothetical-deductive method, observing the existing norms and the need for specific legislation, analyzing the draft Federal Law on the subject and punctuating the necessary specifications for details, as well as making an exploratory research interviewing actors that are inserted in this need of specific norm, given what is observed in the bureaucratic obstacle due to the absence of specific legislation.

Human excreta contain plant nutrients and have the potentialto be used as a fertiliser in agriculture. Urine contributesthe major proportion of the nutrients (N, P and K) in domesticwastewater whereas faeces contribute a smaller amount andinvolves greater health risks if reused due to the possiblepresence of enteric pathogens. Human urine does not generallycontain pathogens that can be transmitted through theenvironment. Source-separation of urine and faeces is possible by usingurine-separating (or urine-diverting) toilets, available assimple dry toilets or porcelain flush toilets with dividedbowls. The risk for transmission of disease when handling andreusing the urine is largely dependent on thecross-contamination by faeces. In this research, the presenceof human faeces in urine samples was successfully determined byanalysing for faecal sterols. Cross-contamination was evidentin 22% of the samples from urine collection tanks, and in thesequantified to an average (± SD) of 9.1 ± 5.6 mgfaeces per litre urine. Testing for indicator bacteria wasshown to be an unsuitable method for determining faecalcontamination in human urine sinceE. colihad a rapid inactivation in the urine and faecalstreptococci were found to grow within the system. The fate of any enteric pathogens present in urine iscrucial for the risk for transmission of infectious diseases.Gram-negative bacteria (e.g.SalmonellaandE. coli) were rapidly inactivated (time for 90%reduction, T90&lt;5 days) in source-separated urine at itsnatural pH-value of 9. Gram-positive faecal streptococci weremore persistent with a T90of approximately 30 days. Clostridia sporenumbers were not reduced at all during 80 days. Similarly,rhesusrotavirus andSalmonella typhimuriumphage 28B were not inactivated inurine at low temperature (5°C), whereas at 20°C theirT90-values were 35 and 71 days, respectively.Cryptosporidiumoocysts were less persistent with a T90of 29 days at 4°C. Factors that affect thepersistence of microorganisms in source-separated human urineinclude temperature, pH, dilution and presence of ammonia. By using Quantitative Microbial Risk Assessment (QMRA), therisks for bacterial and protozoan infections related tohandling and reuse of urine were calculated to be&lt;10-3for all exposure routes independent of the urinestorage time and temperature evaluated. The risk for viralinfection was higher, calculated at 0.56 for accidentalingestion of 1 ml of unstored urine. If the urine was stored at20°C for 6 months the risk for viral infection was reducedto 5.4 × 10-4. By following recommendations for storage and reuse, whichare dependent on the type of crop to be fertilised, it ispossible to significantly decrease the risk for infections. Sofar, the level of risk that is acceptable is unknown. Theacceptable risk will be one of the main factors determining thefuture utilisation of source-separated human urine inagriculture. <b>Keywords:</b>urine-separation, urine, wastewater systems,wastewater reuse, recycling, enteric pathogens, faecal sterols,indicator bacteria, hygiene risks, microbial persistence,microbial risk assessment, QMRA, fertiliser, crop.