The interaction of microorganisms with sediments can enhance their survival by reducing exposure to various stressors and thus marine sediments may act as reservoirs for pathogenic microorganisms. In coastal waters there can be an increased risk of infection to humans due to the possible re-suspension of these microorganisms during recreational activities. This research attempts to more accurately identify environmental exposure in the first stage of a health risk assessment in recreational coastal waters. Techniques were developed to successfully separate microorganisms from sediment particles. Of the methods investigated, subjecting diluted sediment samples to a sonication bath for 10 minutes was found to be the most efficient separation technique over a range of sediment types. This method was therefore used in the subsequent studies to enumerate organisms from the surface sediment layer, as distinct from the water column. Faecal coliforms were enumerated by membrane filtration in both water and sediment from three Adelaide metropolitan recreational coastal sites, chosen to represent different physical sediment characteristics, over a 12-month period. All sites investigated met current National Health and Medical Research Council Guidelines for primary contact recreation. Faecal coliform concentrations were generally greater in sediment compared with overlying water for all samples. This was most evident in sediment consisting of greater silt/clay and organic carbon content (with up to 1000 times higher concentrations in the surface sediment layer compared with overlying water). For coastal recreational sites impacted by stormwater or river discharges, high faecal coliform concentrations were found to be associated with rainfall. A laboratory-based microcosm study utilising intact sediment cores was undertaken to determine the decay rates of faecal indicator organisms (E. coli, enterococci and somatic coliphage) and pathogens (Salmonella derby and S. typhimurium) in both overlying water and in various sediment types. For all organisms tested, temperature had an inverse relationship with survival. Greater decay was observed in the overlying water compared to the surface sediment layer. Small particle size and high organic carbon content was found to be more conducive to microbial survival. In general, decay rates of E. coli were significantly greater than enterococci and coliphage. Although no significant correlations were observed between decay rates of the pathogens and indicator organisms, decay of Salmonella spp. in overlying water more closely resembled that of E. coli than that of other indicators. Using decay rates measured in the microcosm study and available dose-response data, a quantitative microbial risk assessment (QMRA) utilising Monte Carlo simulation was undertaken to estimate the risk of infection to Salmonella spp. and rotavirus following exposure to recreational coastal water subject to a range of faecal contamination levels. For modelling purposes, the assumption was made that rotavirus decay was equivalent to coliphage decay. The probability of infection from rotavirus due to exposure to contaminated recreational coastal water was greater than that for Salmonella spp. under all scenarios. This increased probability of infection is linked to the high infectivity of rotavirus compared to Salmonella spp. Results of this research highlight the limited effectiveness of using prescribed faecal coliform concentrations in the water column alone to estimate the risk of exposure to pathogenic microorganisms during recreational activity at coastal areas. It demonstrated that coastal sediments act as a reservoir for both indicator and pathogenic organisms released into the coastal environment. This suggests an increased exposure risk if these organisms are resuspended back into the water column during recreational activity. A combined risk-based monitoring program would provide a more robust and reliable estimate of health risk associated with coastal recreational areas.

Orientadores: Ricardo Lima Isaac, Marli de Fatima Fiore / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-10T01:46:02Z (GMT). No. of bitstreams: 1 Agujaro_LiviaFernanda_D.pdf: 8426074 bytes, checksum: 8e36c9f4c6c51501d00f8d43de2d0d37 (MD5) Previous issue date: 2007 / Resumo: Florações de cianobactérias potencialmente tóxicas têm sido detectadas em vários reservatórios no Estado de São Paulo, muitos deles com intenso uso recreacional, como o reservatório Salto Grande (Americana, SP). Poucos estudos no Brasil enfocam aspectos de balneabilidade e saúde pública por exposição a estes organismos em corpos d'água interiores. Planos de monitoramento para a avaliação dos riscos associados são inexistentes. Diante dos potenciais problemas de saúde pública, foi desenvolvido um estudo com o objetivo de: efetuar um levantamento qualitativo e quantitativo das cianobactérias, associar os fatores ambientais condicionantes de sua ocorrência, avaliar o potencial toxicológico destas águas e utilizar abordagens moleculares inéditas para o local estudado e ainda pouco empregadas no País. As coletas foram mensais, no período de abril de 2005 a fevereiro de 2006, nas margens e sempre aos domingos. Realizaram-se a contagem e a identificação de organismos e células de cianobactérias, contagem das principais classes fitoplanctônicas, determinação de clorofila a, avaliação de microcistinas pelo método ELISA e microcistina-LR por CLAE e determinação de parâmetros fisicos e químicos. Paralelamente isolaram-se treze linhagens em culturas uniespecíficas para o aprofundamento dos estudos taxonômicos por meio do seqüenciamento do gene rDNA 16S. Linhagens de cianobactérias e amostras ambientais foram submetidas à detecção do gene mycA por PCR e foi verificada a distribuição dos genes NRPS e PKS nos isolados...Observação: O resumo, na íntegra, poderá ser visualizado no texto completo da tese digital / Abstract: Potentially toxic cyanobacteria blooms have been detected in several water reservoirs' with intense recreational use such as in Salto Grande Reservoir, Sao Paulo State, Brazil. Very few studies in this country focus on the related public health aspects. There are no monitoring plans developed by public authorities to evaluate the associated risks. A qualitative and quantitative cyanobacteria research was carried out at the recreational area of the reservoir, connected to the environmental factors which regulate its occurrence in order to evaluate the toxicological potential of these waters, using molecular approaches that have just recently been used in Brazil. The results obtained led to a Cyanobacteria Monitoring Plan for freshwater ecosystems in Sao Paulo State aiming to allow the safe recreational use of these water bodies. It was taken eleven monthly samples during the wet and dry seasons from April 2005 to February 2006 at Namorados Beach and at Iate Clube de Americana, on Sundays, when intense recreational use occurs. The following environmental variables were analyzed: water temperature, precipitation, water flow into the reservoir, Secchi depth, pH, total phosphorus and nitrogen levels, in addition to 'numbering and identifying organisms and cyanobacteria cells, main phytoplankton Classes, chlorophyll-a, besides microcystins assessment by ELISA method and microcystin-LR by HPLC-MS. Simultaneously, thirteen strains were isolated in uni-specific cultures in order to deepen the taxonomic studies through sequencing of rDNA 16S gene. To evaluate the toxigenic potential, the strains of cyanobacterias and the environmental samples were tested to detect mycA by PCR and it was investigated the distribution of NRPS and PKS genes in the isolated strains ...Note: The complete abstract is available with the full electronic digital thesis or dissertations / Doutorado / Saneamento e Ambiente / Doutor em Engenharia Civil

The microbial source tracking (MST) methods of antibiotic resistance analysis (ARA) and fluorometry (to detect optical brighteners in detergents) were used in the summers of 2004 and 2005 to determine the origins of fecal pollution at beaches with a past history of, or the potential for, high enterococci counts and posted advisories. At Hilton and Anderson beaches, ARA and fluorometry in the summer of 2004 detected substantial human-origin pollution in locations producing consistently high counts of Enterococcus spp. Investigations by municipal officials led to the fluorometric detection and subsequent repair of sewage infrastructure problems at both beaches. The success of these mitigation efforts was confirmed during the summer of 2005 using ARA and fluorometry, with the results cross-validated by pulsed-field gel electrophoresis (PFGE). Results at other beaches indicated that birds and/or wildlife were largely responsible for elevated enterococci levels during 2004 and 2005. The application of fluorometry proved difficult in opens waters due to high levels of dilution, but showed potential for use in storm drains. An additional study developed and tested a new library-based MST approach based on the pattern of DNA band lengths produced by the amplification of the 16S-23S rDNA intergenic spacer region, and subsequent digestion using the restriction endonuclease MboI. Initial results from small known-source libraries yielded high average rates of correct classification (ARCC). However, an increase in the library size was accompanied by a reduction in the ARCC of the library and the method was deemed unsuccessful, and unsuitable for field application. A final study focused on the potential for classification bias with disproportionate source category sizes using discriminant analysis (DA), logistic regression (LR), and k-nearest neighbor (K-NN) statistical classification algorithms. Findings indicated that DA was the most robust algorithm for use with source category imbalance when measuring both correct and incorrect classification rates. Conversely k-NN was identified as the most sensitive algorithm to imbalances with the greatest levels of distortion obtained from the highest k values. Conclusions of this project include: 1) application of a validation set, as well as a minimum detectable percentage to known-source libraries aids in accurately assessing the classification power of the library and reducing the false positive identification of contributing fecal sources; 2) the validation of MST results using multiple methods is recommended for field applications; 3) fluorometry displayed potential for detecting optical brighteners as indicators of sewage leaks in storm drains; 4) the digestion of the 16S-23S rDNA intergenic spacer region of Enterococcus spp. using MboI does not provided suitable discriminatory power for use as an MST method; and 5) DA was the least, and k-NN the most, sensitive algorithm to imbalances in the size of source categories in a known-source library. / Ph. D.

O Brasil possui em sua área costeira grandes metrópoles onde diversas atividades humanas são desenvolvidas, podendo trazer prejuízos à qualidade das águas costeiras. O litoral de São Paulo, constituído por 16 municípios incluindo-se Cubatão, apresenta peculiaridades diferenciadas. O tipo de poluição mais encontrado na costa paulista é a poluição fecal causada por despejo de esgotos domésticos, os quais transportam organismos patogênicos cuja presença pode levar a agravos à saúde humana. O objetivo deste estudo é o de avaliar a qualidade sanitária de águas e areias de praias da Baixada Santista. Assim amostras de água e areia (úmida e seca) de três praias, como Gonzaguinha (São Vicente), Boqueirão (Santos) e Pitangueiras (Guarujá) foram coletadas com freqüência mensal pelo período de um ano nas quais foram analisados os seguintes parâmetros: coliformes termotolerantes, Escherichia coli, enterococos, e ainda Staphylococcus coagulase (+), Pseudomonas aeruginosa, Candida albicans e dermatófitos. Para a realização das análises em amostras de água utilizou-se da Técnica da Membrana Filtrante e para as amostras de areia a Técnica de Tubos Múltiplos, de acordo com Normas Técnicas CETESB e Standard Methods. Para a determinação de dermatófitos, as amostras de água foram concentradas pela Técnica de Membrana Filtrante e as amostras de areia (seca e úmida) foram analisadas pela Técnica de inoculação em superfície e, concomitantemente, pela Técnica da Isca de Cabelo. Os resultados obtidos revelaram que 95 por cento das amostras analisadas foram positivas para a presença dos indicadores de contaminação fecal, seguidos por P. aeruginosa, presente em 75 por cento das amostras. C. albicans foi o microrganismo menos freqüente (6,7 por cento) e foi detectada somente nas amostras de água. O dermatófito Microsporum sp foi detectado somente nas amostras de areia e esteve presente nas três praias. De maneira geral, o comportamento das concentrações dos microrganismos foi maior nas amostras de areia seca, independentemente dos eventos de chuva, seguidas pela areia úmida, sendo as menores concentrações observadas nas amostras de água. Concluiu-se que as concentrações dos microrganismos indicadores de poluição fecal e dos patogênicos foram elevadas nas matrizes estudadas e que é necessário dirigir esforços para a melhoria da qualidade das águas e areias, pois as condições observadas trazem preocupação à saúde dos banhistas e freqüentadores das praias / Brazilian seashore comprises many big cities and the diverse activities which are performed in these areas can bring damages to seashore water quality. São Paulo State seashore comprises 16 cities including Cubatão, where each one shows their own particularities. In the São Paulo State seashore is mostly observed fecal pollution due to launching sewage into these waters which transport pathogens with potential to cause diseases. The objective of this study is to assess the sanitary quality of recreational waters and wet and dry sand from three beaches located at Baixada Santista such as Gonzaguinha (São Vicente), Boqueirão (Santos) and Pitangueiras (Guarujá). The samples (water, wet and dry sand) were collected with monthly frequency throughout a year and the following parameters were analyzed: thermotolerant coliforms, Escherichia coli, enterococos, Staphylococcus coagulase +, Pseudomonas aeruginosa, Candida albicans and dermatophytes. The bacteriological and C. albicans analyzes were performed according to CETESB and Standard Methods 21st edition. Dermatophyte analysis from water samples were carried out by membrane filtering technique and by spread plate technique and hair-baiting technique for sand samples. The results revealed that 95 per cent of the water samples were positive for fecal indicators following by P. aeruginosa (75 per cent). C. albicans was detected only in water samples showing 6.7 per cent of the observed frequency. Microsporum sp specie was detected only in sand samples in all beaches studied. In general, high microorganisms concentrations was found in dry sand samples regardless raining events, following by wet sand and the lowest concentrations were found in water samples. It was possible to conclude that fecal indicators microorganisms and pathogens concentrations were high in all samples analyzed and it highlights to necessity to address efforts to improve the quality of the water and sand because this poor quality condition found poses a significant public health concern

O uso das águas costeiras para fins recreacionais está associado com benefícios à saúde e bem-estar, todavia eventuais impactos negativos podem diminuir estes benefícios. Esses usos variam de acordo com o tipo de atividade desenvolvida, sendo que a recreação de contato primário requer contato direto e prolongado com a água, durante a qual pode ocorrer ingestão acidental. A Resolução CONAMA nº 274/2000 dispõe sobre os critérios de balneabilidade e reza que as condições da qualidade das águas recreacionais devem ser avaliadas através de indicadores microbiológicos de contaminação fecal, e ainda recomenda que seja realizada pesquisa de organismos patogênicos em praias sistematicamente impróprias. Dada a escassez de dados da ocorrência de patógenos em águas costeiras, no período de 2010 a 2012, a CETESB realizou o Estudo de microrganismos patogênicos nas praias do Litoral Paulista pesquisando enterovírus, adenovírus, vírus da hepatite A, Cryptosporidium sp e Giardia sp, no intuito de preencher esta lacuna e gerar dados primários. Assim, o objetivo deste trabalho foi estimar a probabilidade de infecção por Cryptosporidium sp e Giardia sp após exposição a águas recreacionais costeiras usando como ferramenta a Avaliação Quantitativa de Risco Microbiológico (AQRM), como também o risco de doença. As concentrações de (oo)cistos nas águas das praias são oriundas dos relatórios de Qualidade das Praias Litorâneas no Estado de São Paulo da CETESB dos anos de 2011 e 2012. Nesse período foram analisadas 203 amostras coletadas de 12 praias na 1ª fase e de cinco praias na 2ª fase para a pesquisa de ocorrência de (oo)cistos. As amostras de água foram coletadas na isóbata de um metro, com frequência mensal. Giardia sp foi o microrganismo mais frequente, presente em 43 por cento das amostras e Cryptosporidium sp em 13 por cento . O cenário de exposição considerou tipos de atividade, tipos de usuários (crianças, adultos e esportistas), concentração de (oo)cistos, volume de ingestão, duração e frequência da exposição. A probabilidade de infecção foi maior em praias com mais amostras positivas para oocistos e cistos, no grupo dos esportistas e para Giardia sp. Em alguns casos os valores de risco de doença ultrapassaram o risco tolerável pela U.S. EPA (2012) de 3,6 por cento casos de gastroenterite, assim como ultrapassaram os resultados de incidência acumulada encontradas por LAMPARELLI et al. (2015). Os resultados apontaram a necessidade de melhoria nos sistemas de tratamento de efluentes no Litoral Paulista. A AQRM é uma ferramenta capaz de estimar a probabilidade de infecção no cenário das águas recreacionais e pode auxiliar no gerenciamento dos riscos. / The use of coastal water for recreational purposes has been associated with benefits to health and well-being; however some negative impacts can diminish such benefits. The usages can vary according to the type of activity but the primary contact demands physical contact resulting in a high probability in accidental ingestion of water. Brazilian legislation for coastal recreational waters CONAMA 274/2000 establishes criteria for fecal indicator bacteria and furthermore recommends investigation of pathogenic organisms for beaches which classification is systematically as improper. Given the scarcity of data referring to pathogenic presence in beaches´ waters, CETESB carried out a study, in 2010 and 2012, for quantifying enterovirus, adenovirus, hepatitis A virus, Cryptosporidium sp and Giardia sp in coastal waters of São Paulo state in order to obtain data about their occurrence of these pathogens in coastal waters. The objective of this study was to estimate the annual risk of infection and disease for Giardia sp and Cryptosporidium sp by ingestion of water during primary contact recreation using QMRA approach. Concentrations of both parasites were taken from the annual report entitled Quality of coastal beaches in São Paulo state by CETESB (2011 and 2012). In these years were analyzed 203 samples of water for quantifying (oo)cysts of Giardia and Cryptosporidium from 12 beaches in the first year and five beaches in the second year of research. The samples were collected at one meter isobaths, with monthly frequency. Giardia was the most frequent parasite present in 43 per cent of samples and Cryptosporidium sp in 13 per cent . Exposure scenario was built considering types of activity, beach goers (children, adults and athletes), concentration of parasites, ingestion rate, duration and frequency of exposure. The probability of annual infection was higher in beaches in which there were more positive results for parasites for athletes and for Giardia infection. The tolerable risk for gastroenteritis by USEPA, which is 3.6 per cent , was overpassed in some cases. Though the results found in this study overpassed the cumulative incidence reported by LAMPARELLI et al. (2015). The results indicate the need for improvements in wastewater treatment systems in the coastal area of São Paulo. As QMRA is a tool capable in estimating the probability of infection it can help to highlight crucial issues in risk management.

O uso das águas costeiras para fins recreacionais está associado com benefícios à saúde e bem-estar, todavia eventuais impactos negativos podem diminuir estes benefícios. Esses usos variam de acordo com o tipo de atividade desenvolvida, sendo que a recreação de contato primário requer contato direto e prolongado com a água, durante a qual pode ocorrer ingestão acidental. A Resolução CONAMA nº 274/2000 dispõe sobre os critérios de balneabilidade e reza que as condições da qualidade das águas recreacionais devem ser avaliadas através de indicadores microbiológicos de contaminação fecal, e ainda recomenda que seja realizada pesquisa de organismos patogênicos em praias sistematicamente impróprias. Dada a escassez de dados da ocorrência de patógenos em águas costeiras, no período de 2010 a 2012, a CETESB realizou o Estudo de microrganismos patogênicos nas praias do Litoral Paulista pesquisando enterovírus, adenovírus, vírus da hepatite A, Cryptosporidium sp e Giardia sp, no intuito de preencher esta lacuna e gerar dados primários. Assim, o objetivo deste trabalho foi estimar a probabilidade de infecção por Cryptosporidium sp e Giardia sp após exposição a águas recreacionais costeiras usando como ferramenta a Avaliação Quantitativa de Risco Microbiológico (AQRM), como também o risco de doença. As concentrações de (oo)cistos nas águas das praias são oriundas dos relatórios de Qualidade das Praias Litorâneas no Estado de São Paulo da CETESB dos anos de 2011 e 2012. Nesse período foram analisadas 203 amostras coletadas de 12 praias na 1ª fase e de cinco praias na 2ª fase para a pesquisa de ocorrência de (oo)cistos. As amostras de água foram coletadas na isóbata de um metro, com frequência mensal. Giardia sp foi o microrganismo mais frequente, presente em 43 por cento das amostras e Cryptosporidium sp em 13 por cento . O cenário de exposição considerou tipos de atividade, tipos de usuários (crianças, adultos e esportistas), concentração de (oo)cistos, volume de ingestão, duração e frequência da exposição. A probabilidade de infecção foi maior em praias com mais amostras positivas para oocistos e cistos, no grupo dos esportistas e para Giardia sp. Em alguns casos os valores de risco de doença ultrapassaram o risco tolerável pela U.S. EPA (2012) de 3,6 por cento casos de gastroenterite, assim como ultrapassaram os resultados de incidência acumulada encontradas por LAMPARELLI et al. (2015). Os resultados apontaram a necessidade de melhoria nos sistemas de tratamento de efluentes no Litoral Paulista. A AQRM é uma ferramenta capaz de estimar a probabilidade de infecção no cenário das águas recreacionais e pode auxiliar no gerenciamento dos riscos. / The use of coastal water for recreational purposes has been associated with benefits to health and well-being; however some negative impacts can diminish such benefits. The usages can vary according to the type of activity but the primary contact demands physical contact resulting in a high probability in accidental ingestion of water. Brazilian legislation for coastal recreational waters CONAMA 274/2000 establishes criteria for fecal indicator bacteria and furthermore recommends investigation of pathogenic organisms for beaches which classification is systematically as improper. Given the scarcity of data referring to pathogenic presence in beaches´ waters, CETESB carried out a study, in 2010 and 2012, for quantifying enterovirus, adenovirus, hepatitis A virus, Cryptosporidium sp and Giardia sp in coastal waters of São Paulo state in order to obtain data about their occurrence of these pathogens in coastal waters. The objective of this study was to estimate the annual risk of infection and disease for Giardia sp and Cryptosporidium sp by ingestion of water during primary contact recreation using QMRA approach. Concentrations of both parasites were taken from the annual report entitled Quality of coastal beaches in São Paulo state by CETESB (2011 and 2012). In these years were analyzed 203 samples of water for quantifying (oo)cysts of Giardia and Cryptosporidium from 12 beaches in the first year and five beaches in the second year of research. The samples were collected at one meter isobaths, with monthly frequency. Giardia was the most frequent parasite present in 43 per cent of samples and Cryptosporidium sp in 13 per cent . Exposure scenario was built considering types of activity, beach goers (children, adults and athletes), concentration of parasites, ingestion rate, duration and frequency of exposure. The probability of annual infection was higher in beaches in which there were more positive results for parasites for athletes and for Giardia infection. The tolerable risk for gastroenteritis by USEPA, which is 3.6 per cent , was overpassed in some cases. Though the results found in this study overpassed the cumulative incidence reported by LAMPARELLI et al. (2015). The results indicate the need for improvements in wastewater treatment systems in the coastal area of São Paulo. As QMRA is a tool capable in estimating the probability of infection it can help to highlight crucial issues in risk management.

O Brasil possui em sua área costeira grandes metrópoles onde diversas atividades humanas são desenvolvidas, podendo trazer prejuízos à qualidade das águas costeiras. O litoral de São Paulo, constituído por 16 municípios incluindo-se Cubatão, apresenta peculiaridades diferenciadas. O tipo de poluição mais encontrado na costa paulista é a poluição fecal causada por despejo de esgotos domésticos, os quais transportam organismos patogênicos cuja presença pode levar a agravos à saúde humana. O objetivo deste estudo é o de avaliar a qualidade sanitária de águas e areias de praias da Baixada Santista. Assim amostras de água e areia (úmida e seca) de três praias, como Gonzaguinha (São Vicente), Boqueirão (Santos) e Pitangueiras (Guarujá) foram coletadas com freqüência mensal pelo período de um ano nas quais foram analisados os seguintes parâmetros: coliformes termotolerantes, Escherichia coli, enterococos, e ainda Staphylococcus coagulase (+), Pseudomonas aeruginosa, Candida albicans e dermatófitos. Para a realização das análises em amostras de água utilizou-se da Técnica da Membrana Filtrante e para as amostras de areia a Técnica de Tubos Múltiplos, de acordo com Normas Técnicas CETESB e Standard Methods. Para a determinação de dermatófitos, as amostras de água foram concentradas pela Técnica de Membrana Filtrante e as amostras de areia (seca e úmida) foram analisadas pela Técnica de inoculação em superfície e, concomitantemente, pela Técnica da Isca de Cabelo. Os resultados obtidos revelaram que 95 por cento das amostras analisadas foram positivas para a presença dos indicadores de contaminação fecal, seguidos por P. aeruginosa, presente em 75 por cento das amostras. C. albicans foi o microrganismo menos freqüente (6,7 por cento) e foi detectada somente nas amostras de água. O dermatófito Microsporum sp foi detectado somente nas amostras de areia e esteve presente nas três praias. De maneira geral, o comportamento das concentrações dos microrganismos foi maior nas amostras de areia seca, independentemente dos eventos de chuva, seguidas pela areia úmida, sendo as menores concentrações observadas nas amostras de água. Concluiu-se que as concentrações dos microrganismos indicadores de poluição fecal e dos patogênicos foram elevadas nas matrizes estudadas e que é necessário dirigir esforços para a melhoria da qualidade das águas e areias, pois as condições observadas trazem preocupação à saúde dos banhistas e freqüentadores das praias / Brazilian seashore comprises many big cities and the diverse activities which are performed in these areas can bring damages to seashore water quality. São Paulo State seashore comprises 16 cities including Cubatão, where each one shows their own particularities. In the São Paulo State seashore is mostly observed fecal pollution due to launching sewage into these waters which transport pathogens with potential to cause diseases. The objective of this study is to assess the sanitary quality of recreational waters and wet and dry sand from three beaches located at Baixada Santista such as Gonzaguinha (São Vicente), Boqueirão (Santos) and Pitangueiras (Guarujá). The samples (water, wet and dry sand) were collected with monthly frequency throughout a year and the following parameters were analyzed: thermotolerant coliforms, Escherichia coli, enterococos, Staphylococcus coagulase +, Pseudomonas aeruginosa, Candida albicans and dermatophytes. The bacteriological and C. albicans analyzes were performed according to CETESB and Standard Methods 21st edition. Dermatophyte analysis from water samples were carried out by membrane filtering technique and by spread plate technique and hair-baiting technique for sand samples. The results revealed that 95 per cent of the water samples were positive for fecal indicators following by P. aeruginosa (75 per cent). C. albicans was detected only in water samples showing 6.7 per cent of the observed frequency. Microsporum sp specie was detected only in sand samples in all beaches studied. In general, high microorganisms concentrations was found in dry sand samples regardless raining events, following by wet sand and the lowest concentrations were found in water samples. It was possible to conclude that fecal indicators microorganisms and pathogens concentrations were high in all samples analyzed and it highlights to necessity to address efforts to improve the quality of the water and sand because this poor quality condition found poses a significant public health concern

La pollution microbienne des eaux récréatives peut engendrer un risque pour la santé des populations exposées. La contamination fécale de ces eaux représente une composante importante de ce risque, notamment par la présence possible d’agents pathogènes et par l’exposition à des micro-organismes résistants aux antimicrobiens. Les sources de pollution fécale sont multiples et incluent entre autres les activités agricoles et les productions animales. Ce projet visait donc à mieux comprendre les facteurs influençant la qualité microbiologique des eaux récréatives du Québec méridional, en ciblant le rôle possible des activités agricoles, ainsi qu`à proposer et évaluer de nouvelles sources de données pouvant contribuer à l’identification de ces facteurs. Dans un premier temps, une évaluation de la présence d’Escherichia coli résistants aux antimicrobiens dans les eaux récréatives à l’étude a été effectuée. À la lumière des résultats de cette première étude, ces eaux représenteraient une source de micro-organismes résistants aux antimicrobiens pour les personnes pratiquant des activités aquatiques, mais l’impact en santé publique d’une telle exposition demeure à déterminer. Les déterminants agroenvironnementaux associés à la présence de micro-organismes résistants aux antimicrobiens ont par la suite été explorés. Les résultats de ce chapitre suggèrent que les activités agricoles, et plus spécifiquement l’épandage de fumier liquide, seraient reliées à la contamination des eaux récréatives par des bactéries résistantes aux antimicrobiens. Le chapitre suivant visait à identifier des déterminants agroenvironnementaux temps-indépendants d’importance associés à la contamination fécale des eaux à l’étude. Différentes variables, regroupées en trois classes (activités agricoles, humaines et caractéristiques géohydrologiques), ont été explorées à travers un modèle de régression logistique multivarié. Il en est ressorti que les eaux récréatives ayant des sites de productions de ruminants à proximité, et en particulier à l’intérieur d’un rayon de 2 km, possédaient un risque plus élevé de contamination fécale. Une association positive a également été notée entre le niveau de contamination fécale et le fait que les plages soient situées à l’intérieur d’une zone urbaine. Cette composante nous permet donc de conclure qu’en regard à la santé publique, les eaux récréatives pourraient être contaminées par des sources de pollution fécale tant animales qu’humaines, et que celles-ci pourraient représenter un risque pour la santé des utilisateurs. Pour terminer, un modèle de régression logistique construit à l’aide de données issues de la télédétection et mettant en association un groupe de déterminants agroenvironnementaux et la contamination fécale des eaux récréatives a été mis au point. Ce chapitre visait à évaluer l’utilité de telles données dans l’identification de ces déterminants, de même qu`à discuter des avantages et contraintes associées à leur emploi dans le contexte de la surveillance de la qualité microbiologique des eaux récréatives. À travers cette étude, des associations positives ont été mises en évidence entre le niveau de contamination fécale des eaux et la superficie des terres agricoles adjacentes, de même qu’avec la présence de surfaces imperméables. Les données issues des images d’observation de la Terre pourraient donc constituer une valeur ajoutée pour les programmes de suivi de la qualité microbiologique de ces eaux en permettant une surveillance des déterminants y étant associés. / Microbial pollution of recreational waters may constitute a health risk for exposed populations. Fecal contamination of these waters represents an important component of this risk, especially due to the possible presence of pathogens and exposure to antimicrobial resistant microorganisms. Sources of fecal pollution are many and include agricultural activities and animal production. This project aims to better understand agroenvironmental factors influencing the microbiological quality of recreational waters of Southern Quebec and also suggests and assesses new sources of data which may contribute to the identification of these factors. An evaluation of the presence of antimicrobial resistant Escherichia coli in the recreational waters studied was first performed. Given the positive results found, certain bodies of waters may represent a source of antimicrobial resistant microorganisms for people engaged in water activities. However the public health impact of such exposure is still unknown. Agroenvironmental determinants associated with the presence of antimicrobial resistant microorganisms were investigated. Results of this chapter suggest that agricultural activities, especially liquid manure spreading, may be associated with the contamination of recreational waters with antimicrobial resistant microorganisms. The next chapter assesses key time-independent agroenvironmental determinants associated with the fecal contamination of studied recreational waters. Various variables – classified as either agricultural activities, human activities or geo-hydrological characteristics – are explored through a multivariate logistic regression model. It appears that recreational waters with ruminant productions in their proximal environment, especially when they are within a radius of 2 km, may present a higher risk of fecal contamination. A positive association was also noticed between the level of fecal contamination of a beach and its presence in an urban area. From a public health perspective, recreational waters may be contaminated by animal and human sources and these sources may represent a risk for bathers’ health. Finally, association between fecal contamination of recreational waters and agroenvironment determinants was studied through a logistic regression model built from remote sensing data. This chapter assesses the utility of such data in the identification of these determinants and discusses the strengths and the limitations of their use in the context of the monitoring of the microbiological quality of recreational waters. In this study, positive associations were found between the level of fecal contamination and both the proximity of agricultural lands and the presence of impervious surfaces. Earth observation data may constitute an added value for the water quality monitoring program in allowing the surveillance of the determinants associated with this quality.

La pollution microbienne des eaux récréatives peut engendrer un risque pour la santé des populations exposées. La contamination fécale de ces eaux représente une composante importante de ce risque, notamment par la présence possible d’agents pathogènes et par l’exposition à des micro-organismes résistants aux antimicrobiens. Les sources de pollution fécale sont multiples et incluent entre autres les activités agricoles et les productions animales. Ce projet visait donc à mieux comprendre les facteurs influençant la qualité microbiologique des eaux récréatives du Québec méridional, en ciblant le rôle possible des activités agricoles, ainsi qu`à proposer et évaluer de nouvelles sources de données pouvant contribuer à l’identification de ces facteurs. Dans un premier temps, une évaluation de la présence d’Escherichia coli résistants aux antimicrobiens dans les eaux récréatives à l’étude a été effectuée. À la lumière des résultats de cette première étude, ces eaux représenteraient une source de micro-organismes résistants aux antimicrobiens pour les personnes pratiquant des activités aquatiques, mais l’impact en santé publique d’une telle exposition demeure à déterminer. Les déterminants agroenvironnementaux associés à la présence de micro-organismes résistants aux antimicrobiens ont par la suite été explorés. Les résultats de ce chapitre suggèrent que les activités agricoles, et plus spécifiquement l’épandage de fumier liquide, seraient reliées à la contamination des eaux récréatives par des bactéries résistantes aux antimicrobiens. Le chapitre suivant visait à identifier des déterminants agroenvironnementaux temps-indépendants d’importance associés à la contamination fécale des eaux à l’étude. Différentes variables, regroupées en trois classes (activités agricoles, humaines et caractéristiques géohydrologiques), ont été explorées à travers un modèle de régression logistique multivarié. Il en est ressorti que les eaux récréatives ayant des sites de productions de ruminants à proximité, et en particulier à l’intérieur d’un rayon de 2 km, possédaient un risque plus élevé de contamination fécale. Une association positive a également été notée entre le niveau de contamination fécale et le fait que les plages soient situées à l’intérieur d’une zone urbaine. Cette composante nous permet donc de conclure qu’en regard à la santé publique, les eaux récréatives pourraient être contaminées par des sources de pollution fécale tant animales qu’humaines, et que celles-ci pourraient représenter un risque pour la santé des utilisateurs. Pour terminer, un modèle de régression logistique construit à l’aide de données issues de la télédétection et mettant en association un groupe de déterminants agroenvironnementaux et la contamination fécale des eaux récréatives a été mis au point. Ce chapitre visait à évaluer l’utilité de telles données dans l’identification de ces déterminants, de même qu`à discuter des avantages et contraintes associées à leur emploi dans le contexte de la surveillance de la qualité microbiologique des eaux récréatives. À travers cette étude, des associations positives ont été mises en évidence entre le niveau de contamination fécale des eaux et la superficie des terres agricoles adjacentes, de même qu’avec la présence de surfaces imperméables. Les données issues des images d’observation de la Terre pourraient donc constituer une valeur ajoutée pour les programmes de suivi de la qualité microbiologique de ces eaux en permettant une surveillance des déterminants y étant associés. / Microbial pollution of recreational waters may constitute a health risk for exposed populations. Fecal contamination of these waters represents an important component of this risk, especially due to the possible presence of pathogens and exposure to antimicrobial resistant microorganisms. Sources of fecal pollution are many and include agricultural activities and animal production. This project aims to better understand agroenvironmental factors influencing the microbiological quality of recreational waters of Southern Quebec and also suggests and assesses new sources of data which may contribute to the identification of these factors. An evaluation of the presence of antimicrobial resistant Escherichia coli in the recreational waters studied was first performed. Given the positive results found, certain bodies of waters may represent a source of antimicrobial resistant microorganisms for people engaged in water activities. However the public health impact of such exposure is still unknown. Agroenvironmental determinants associated with the presence of antimicrobial resistant microorganisms were investigated. Results of this chapter suggest that agricultural activities, especially liquid manure spreading, may be associated with the contamination of recreational waters with antimicrobial resistant microorganisms. The next chapter assesses key time-independent agroenvironmental determinants associated with the fecal contamination of studied recreational waters. Various variables – classified as either agricultural activities, human activities or geo-hydrological characteristics – are explored through a multivariate logistic regression model. It appears that recreational waters with ruminant productions in their proximal environment, especially when they are within a radius of 2 km, may present a higher risk of fecal contamination. A positive association was also noticed between the level of fecal contamination of a beach and its presence in an urban area. From a public health perspective, recreational waters may be contaminated by animal and human sources and these sources may represent a risk for bathers’ health. Finally, association between fecal contamination of recreational waters and agroenvironment determinants was studied through a logistic regression model built from remote sensing data. This chapter assesses the utility of such data in the identification of these determinants and discusses the strengths and the limitations of their use in the context of the monitoring of the microbiological quality of recreational waters. In this study, positive associations were found between the level of fecal contamination and both the proximity of agricultural lands and the presence of impervious surfaces. Earth observation data may constitute an added value for the water quality monitoring program in allowing the surveillance of the determinants associated with this quality.