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Made available in DSpace on 2014-10-09T12:28:37Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:57:29Z (GMT). No. of bitstreams: 0 / Em outubro de 2005 a notificação de 17 casos de doença ocular de etiologia desconhecida, envolvendo, em sua maioria, a população infantil da cidade de Araguatins/TO, levou as autoridades locais a pedirem ajuda a Secretaria de Estado da Saúde do Estado do Tocantins no intuito de descobrirem sua etiologia, tratamento e prevenção. Nos pacientes acometidos, os sinais freqüentemente observados foram: intensa hiperemia conjutival, granuloma, episclerite, infiltrado corneano periférico. Na anamnese realizada nos pacientes foi observado que todos tiveram contato com as águas do Rio Araguaia. Os resultados obtidos a partir do processamento das amostras de água, sedimentos e substratos particularmente na vegetação marginal inundada, permitiram confirmar a hipótese de que deveria haver uma fauna rica de esponjas no Araguaia, no trecho fronteiro à cidade de Araguatins A presença intraocular de espícula de esponja de água doce das espécies Drulia uruguayensis e Oncosclera navicela foi confirmada em material avaliado histopatologicamente proveniente de três pacientes que haviam sido submetidos a lensectomia, sugerindo que espículas de água doce poderiam ser um surpreendente novo agente etiológico de patologia ocular. Assim, neste estudo foram realizados ensaios de citotoxicidade com amostras de duas espécies de esponjas coletadas no local. Os resultados indicam que os extratos das esponjas após filtração em filtro Millipore 0,45 μm continuaram apresentando atividade citotóxica, sugerindo haver um componente SOLÚVEL, e não somente espículas, capaz de induzir morte celular na população de células utilizadas. Os indivíduos acometidos foram na maioria do sexo masculino com idade entre 05 e 14 anos. / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

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Lodos de duas Estações de Tratamento de Água (ETA) que utilizam cloreto férrico (ETA-Paiol-ETA-1) e sulfato de alumínio (ETA-SAAE-ETA-2) como coagulantes, foram caracterizados físico-quimicamente em duas estações do ano (chuvosa e seca) e submetidos a testes de toxicidade aguda com microcrustáceos (Daphnia similis), quironomídeos (Chironomus xanthus) e peixes (Hyphessobrycon eques) e de toxicidade crônica com microcrustáceos (D. similis). Observou-se ainda os efeitos destes lodos na comunidade bentônica dos corpos d\'água que recebem os lançamentos das ETAs. Os efeitos dos lodos nos testes de toxicidade aguda foram observados em relação a mortalidade, e, quanto aos testes de toxicidade crônica, observou-se os efeitos na reprodução (número de neonatas) e na mortalidade. Em geral, os lodos das duas ETAs não causaram toxicidade aguda aos organismos-teste, ocorrendo apenas indícios de toxicidade. O lodo da ETA que utilizava cloreto férrico causou toxicidade crônica, que foi observada na reprodução (baixo número de neonatas) e na alta taxa de mortalidade, enquanto que o lodo da ETA que utilizava sulfato de alumínio causou toxicidade crônica evidenciada apenas em relação a reprodução. Os lodos causaram efeitos adversos à fauna bentônica, evidenciados pela predominância de Diptera nos pontos de lançamento das ETAs nos corpos receptores. Constatou-se ainda a variação temporal na caracterização dos lodos em relação aos parâmetros: pH, turbidez, série de sólidos, nutrientes (N e P) e metais (AI, Mn e Fe), sendo que estes, juntamente com a DQO, foram identificados como os principais parâmetros que aumentam a degradação dos corpos receptores que recebem os lançamentos dos efluentes das ETAs. Portanto, a disposição \"in natura\" dos efluentes das ETAs prejudica à biota aquática e compromete a qualidade da água e do sedimento dos corpos receptores. / Sludges from two water treatment plants, which use ferric chloride (ETA-Paiol-ETA-1) and alum (ETA-SAAE-ETA-2) as coagulants were characterized physicall y and chemically at two seasons (wet and dry). The sludge was subjected to acute toxicity tests to cladoceran (Daphnis similis), midges (Chironomus xanthus) and fishes (Hyphessobrycon eques) and chronic toxicity tests using clacloceran (D. similis). It also was observed the impact of discharged sludge on benthic communities in surface waters at two water treatment plants. Acute toxicity tests evaluated sludge effects on mortality, while chronic toxicity tests assessed effects on reproduction and mortality. In general, sludges from two water treatment plants did not show acute toxicity on organisms-test, only toxicity traces. Ferric chloride sludge showed chronic toxicity on lower brood production and high mortality rate. Alum sludge showed chronic toxicity only on brood production. Sludges from water treatment plants caused detrimental effects to benthic macroinvertebrate communities. This effect was determined by Diptera predominance at bodies receiving discharge from water treatment plants. The turbidity, solids series, nutrients (N and P) and metals (Al, Mn and Fe) in the sludge vary when experiments are carried out in the dry and wet season. Together with COD, there were the main parameters that cause the increase in degradation of bodies receiving discharge from water treatment plants. Thus the disposal of \"in natura\" effluents from water treatment plants damages aquatic biota and affects receiving bodies water and sediment quality.

Orientadores: Leonardo Fernandes Fraceto, Vera Lucia Scherholz Salgado de Castro / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-25T14:27:11Z (GMT). No. of bitstreams: 1 Clemente_Zaira_D.pdf: 3720212 bytes, checksum: 1769ff8be9463431799911a24a3f963a (MD5) Previous issue date: 2014 / Resumo: A ecotoxicologia de nanopartículas de dióxido de titânio (nano- TiO2) tem sido amplamente estudada nos últimos anos, mas os resultados obtidos ainda são inconclusivos. Assim, permanecem dúvidas sobre a aplicabilidade dos atuais protocolos ecotoxicológicos para avaliação dos possíveis impactos do uso da nanotecnologia. Poucas investigações toxicológicas tem considerado as propriedades fotocatalíticas da substância, que podem aumentar a sua toxicidade para a biota aquática. O objetivo deste trabalho foi avaliar os efeitos em organismos aquáticos expostos a diferentes nano- TiO2, sob diferentes condições de iluminação. A interação de variáveis como concentração, fase cristal (anatase puro - TA , ou uma mistura de anatase e rutilo - TM) e da condição de iluminação ( luz visível ou luz ultravioleta e visível) foram investigadas através da observação de parâmetros de letalidade e de efeitos subletais em peixes juvenis (pacu caranha, Piaractus mesopotamicus), embriões de peixe (zebrafish, Danio rerio) e microcrustáceos (Daphnia similis e Artemia salina). A exposição aguda e prolongada de peixes juvenis não causou mortalidade nem acúmulo de Ti em músculo dos peixes, mas houve efeitos bioquímicos e genéticos, que dependeram da fase cristal e da condição de iluminação empregada. A atividade de fosfatase ácida (FA), bem como os níveis de proteínas carboniladas (PCO) e de metalotioneína foram biomarcadores úteis de exposição aguda ao nano -TiO2. Por outro lado, os resultados mostraram que para a exposição prolongada, a atividade específica da catalase (CAT), glutationa S-transferase (GST), os níveis de PCO e o ensaio cometa foram os biomarcadores mais úteis. O nano-TiO2 também foi considerado praticamente não tóxico sob luz visível para D. similis e A. salina. A exposição ao nano -TiO2, sob luz visível e ultravioleta aumentou a toxicidade dos nano-TiO2 para microcrustáceos. No caso de D. similis, TM foi mais tóxico do que o TA , mostrando valores de CE5048h = 60,16 e 750,55 mg/L, respectivamente. A A. salina foi mais sensível do que D. similis, com CE5048h = 4 mg/L para ambos os produtos. Em concentrações subletais, o nano- TiO2 não apresentou qualquer impacto negativo sobre o crescimento de Daphnia e Artemia. As atividades específicas de CAT, superóxido dismutase e FA foram biomarcadores úteis de exposição ao nano- TiO2 em Daphnia. Para embriões, a exposição ao nano-TiO2 causou eclosão precoce. Sob luz ultravioleta, o nano- TiO2 causou redução no comprimento das larvas. Além disso, um aumento no número de larvas com alteração de equilíbrio e na mortalidade foi observado nos grupos expostos a TM sob luz ultravioleta. As atividades específicas de CAT e GST apresentaram boa resposta em embriões expostos ao nano-TiO2. A determinação da toxicidade do nano- TiO2 depende do organismo, meio de cultura e o tempo de exposição utilizado nos bioensaios. Depende também da fase cristal e das condições de iluminação. Verificou-se que a exposição à radiação ultravioleta a níveis ambientais mínimos aumenta a toxicidade do nano-TiO2. Os resultados indicam a ocorrência de estresse oxidativo em conseqüência da exposição ao nano-TiO2, mas em geral, não houve uma clara relação concentração- resposta ao considerar parâmetros subletais. Isto pode estar relacionado com a instabilidade dos sistemas de exposição, devido a agregação e precipitação das nanopartículas. Entretanto, nossos resultados indicam que a influência de fatores abióticos sobre a ecotoxicidade do nano- TiO2 deve ser explorada em detalhes, a fim de estabelecer modelos experimentais adequados para estudar a sua toxicidade em espécies de relevância ambiental e contribuir para o desenvolvimento sustentável da nanotecnologia / Abstract: The ecotoxicology of titanium dioxide nanoparticles (nano-TiO2) has been extensively studied in recent years but the results are so far confusing. Hence, doubts remain about the applicability of current ecotoxicological protocols to evaluate the possible impacts of nanotechnology. Few toxicological investigations have considered the photocatalytic properties of the substance, which can increase its toxicity to aquatic biota. The aim of this work was to evaluate the effects on aquatic organisms exposed to different nano-TiO2, under different illumination conditions. The interaction of variables as concentration, crystal phase (pure anatase ¿ TA, or a mixture of anatase and rutile ¿ TM) and illumination condition (visible light or ultraviolet and visible light) were investigated by observing lethal an sublethal parameters in juveniles fishes (pacu caranha, Piaractus mesopotamicus), fish embryos (zebrafish, Danio rerio) and microcrustaceans (Daphnia similis and Artemia salina). The acute and prolonged exposure of juvenile fishes caused no mortality neither Ti accumulation in fish muscle, but showed biochemical and genetic effects, which depends on the crystal phase and the illumination condition employed. The acid phosphatase activity (AP) as well as the metallothionein and protein carbonylation (PCO) levels and the micronucleus test were useful biomarkers of acute exposure of fish to nano-TiO2. On the other side, the findings showed that for prolonged exposure, the specific activity of catalase (CAT), glutathione S-transferase (GST), PCO levels and comet assay were more useful as biomarkers. Nano-TiO2 was also considered pratically non-toxic under visible light to D. similis and A. salina. Exposure to nano-TiO2 under visible and ultraviolet light enhanced the toxicity of nano-TiO2 to microcrustaceans. In the case of D. similis, TM was more toxic than TA, showing values of EC5048h = 60.16 and 750.55 mg/L, respectively. A. salina was more sensitive than D. similis, with EC5048h = 4 mg/L for both products. At sublethal concentrations, the nano-TiO2 did not show any negative impacts on the growth of Daphnia and Artemia. The specific activities of CAT, AP and superoxide dismutase were usefull biomarkers of nano-TiO2 exposure in Daphnia. To embryos the nano-TiO2 exposure caused early hatching. Under ultraviolet light, nano-TiO2 caused reduction in larvae length. Also, an increase in larvae with alteration in equilibrium and larvae mortality was observed in groups exposed to TM under ultraviolet light. The specific activities of CAT and GST showed good answer in embryos exposed to nano-TiO2. Determination of the nano-TiO2 toxicity using bioassays depends on the organism, culture medium, and exposure time employed. It also depends on the crystal phase and the illumination condition. Exposure to ultraviolet light at minimal environmental levels increases the nano-TiO2 toxicity. The results indicate the occurrence of oxidative stress in consequence of nano-TiO2 exposure, but in general there was not a clear concentration-response relationship when considering sublethal parameters. This can be related to the instability of exposure systems, due to nanoparticles aggregation and precipitation. However, our results indicates that the influence of abiotic factors on nano-TiO2 ecotoxicity must be explored in detail, in order to establish experimental models to study their toxicity to environmentally relevant species and contribute to nanotechnology development in a sustainable way. The ecotoxicology of titanium dioxide nanoparticles (nano-TiO2) has been extensively studied in recent years but the results are so far confusing. Hence, doubts remain about the applicability of current ecotoxicological protocols to evaluate the possible impacts of nanotechnology. Few toxicological investigations have considered the photocatalytic properties of the substance, which can increase its toxicity to aquatic biota. The aim of this work was to evaluate the effects on aquatic organisms exposed to different nano-TiO2, under different illumination conditions. The interaction of variables as concentration, crystal phase (pure anatase ¿ TA, or a mixture of anatase and rutile ¿ TM) and illumination condition (visible light or ultraviolet and visible light) were investigated by observing lethal an sublethal parameters in juveniles fishes (pacu caranha, Piaractus mesopotamicus), fish embryos (zebrafish, Danio rerio) and microcrustaceans (Daphnia similis and Artemia salina). The acute and prolonged exposure of juvenile fishes caused no mortality neither Ti accumulation in fish muscle, but showed biochemical and genetic effects, which depends on the crystal phase and the illumination condition employed. The acid phosphatase activity (AP) as well as the metallothionein and protein carbonylation (PCO) levels and the micronucleus test were useful biomarkers of acute exposure of fish to nano-TiO2. On the other side, the findings showed that for prolonged exposure, the specific activity of catalase (CAT), glutathione S-transferase (GST), PCO levels and comet assay were more useful as biomarkers. Nano-TiO2 was also considered pratically non-toxic under visible light to D. similis and A. salina. Exposure to nano-TiO2 under visible and ultraviolet light enhanced the toxicity of nano-TiO2 to microcrustaceans. In the case of D. similis, TM was more toxic than TA, showing values of EC5048h = 60.16 and 750.55 mg/L, respectively. A. salina was more sensitive than D. similis, with EC5048h = 4 mg/L for both products. At sublethal concentrations, the nano-TiO2 did not show any negative impacts on the growth of Daphnia and Artemia. The specific activities of CAT, AP and superoxide dismutase were usefull biomarkers of nano-TiO2 exposure in Daphnia. To embryos the nano-TiO2 exposure caused early hatching. Under ultraviolet light, nano-TiO2 caused reduction in larvae length. Also, an increase in larvae with alteration in equilibrium and larvae mortality was observed in groups exposed to TM under ultraviolet light. The specific activities of CAT and GST showed good answer in embryos exposed to nano-TiO2. Determination of the nano-TiO2 toxicity using bioassays depends on the organism, culture medium, and exposure time employed. It also depends on the crystal phase and the illumination condition. Exposure to ultraviolet light at minimal environmental levels increases the nano-TiO2 toxicity. The results indicate the occurrence of oxidative stress in consequence of nano-TiO2 exposure, but in general there was not a clear concentration-response relationship when considering sublethal parameters. This can be related to the instability of exposure systems, due to nanoparticles aggregation and precipitation. However, our results indicates that the influence of abiotic factors on nano-TiO2 ecotoxicity must be explored in detail, in order to establish experimental models to study their toxicity to environmentally relevant species and contribute to nanotechnology development in a sustainable way / Doutorado / Bioquimica / Doutora em Biologia Funcional e Molecular

Orientadores: Edson Aparecido Abdul Nour, Angela dos Santos Barretto / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-18T23:01:38Z (GMT). No. of bitstreams: 1 Santos_EloisaMariadosReisdos_M.pdf: 6258003 bytes, checksum: b7f23780de2803fe78e2f875075800dd (MD5) Previous issue date: 2011 / Resumo: O presente estudo teve como objetivo avaliar a eficiência na redução da concentração de formaldeído do efluente de um sistema de tratamento combinado: filtro anaeróbio (FA), seguido de biofiltro aerado submerso (BAS) e decantador, por meio de testes de toxicidade utilizando as espécies Pseudokirchneriella subcapitata, Daphnia similis, Poecilia reticulata e Girardia tigrina. O experimento foi desenvolvido nas dependências do Laboratório de Saneamento da FEC/UNICAMP. Os 3 pontos de coleta foram: efluente bruto mais formaldeído, saída do FA e saída do decantador, correspondendo ao efluente tratado pelo sistema. O estudo foi dividido em quatro fases diferenciadas pela concentração teórica de formaldeído aplicada: Fase 1 (F1) - 100 mg L-1, Fase 2 (F2) - 200 mg L-1, Fase 3 (F3) - 400 mg L-1 e Fase 4 (F4) - 500 mg L-1. A água residuária que foi utilizada neste estudo apresentava características condizentes às de um esgoto sanitário de média concentração em termos de matéria orgânica. Em cada fase de operação, a concentração média e a porcentagem de redução do formaldeído no efluente tratado pelo sistema foram de 0,1 mg L-1 e 99,9% (F1); 0,1 mg L-1 e 100% (F2); 0,7 mg L-1 e 99,8% (F3) e 3,8 e 99,2% (F4). O valor médio da concentração e da porcentagem de remoção de DQO total para o efluente tratado pelo sistema, durante o período de estudo foi de 53 mg L-1 e 87% (F1), 41 mg L-1 e 93% (F2), 62 mg L-1 e 93% (F3) e 131 mg L-1 e 90% (F4). O efluente do sistema combinado não apresentou toxicidade aguda para D. similis em todas as concentrações teóricas afluentes aplicadas. Na F1 o efluente do sistema apresentou toxicidade aguda pouco significativa para P. subcapitata e P. reticulata; na F2 para G. tigrina e P. reticulata, na F3 para P. subcapitata, P. reticulata; e G. tigrina. Na F4 o efluente foi significativamente tóxico aos organismos: P. subcapitata, P. reticulata e G. tigrina. As espécies estudadas indicaram serem organismos-teste adequados a estudos de toxicidade de esgoto sanitário contendo formaldeído tratado pelo sistema combinado alvo do estudo. Pelos resultados obtidos, o sistema combinado, na configuração utilizada neste estudo, foi considerado adequado à redução da toxicidade para as concentrações de formaldeído presentes, exceto para a concentração de 500 mg L-1, tóxica a três organismos-teste, sendo necessário um período maior de monitoramento para garantir a adaptação da biomassa a fim de reduzir a toxicidade do efluente / Abstract: This study aimed to evaluate the efficiency in reducing formaldehyde concentration in the effluent of a system of combined treatment: anaerobic filter (AF), followed by aerated submerged biofilter (BAS) and decanter through toxicity tests using species Pseudokirchneriella subcapitata, Daphnia similis, Poecilia reticulata and Girardia tigrina. The experiment was developed in the Sanitation Laboratory FEC / UNICAMP. The three collection points were raw effluent more formaldehyde, AF output and output of the decanter, corresponding to the effluent treated by the system. The study was divided into four phases distinguished by the theoretical concentration of formaldehyde applied: Phase 1 (F1) - 100 mg L-1, Phase 2 (F2) - 200 mg L-1, Phase 3 (F3) - 400 mg L-1 and Phase 4 (F4) - 500 mg L-1. The wastewater which was used in this study had characteristics consistent with those of an average concentration of sewage in terms of organic matter. At each stage of operation, the average concentration and percentage reduction of formaldehyde in the effluent treated by the system was 0.1 mg L-1 and 99.9% (F1), 0.1 mg L-1 and 100% (F2) 0 , 7 mg L-1 and 99.8% (F3) and 3.8 and 99.2% (F4). The average concentration and percentage of total COD removal for the treated effluent through the system, Section 3, during the study period was 53 mg L-1 and 87% (F1), 41 mg L-1 and 93% (F2), 62 mg L-1 and 93% (F3) and 131 mg L-1 and 90% (F4). The effluent of the combined system showed no acute toxicity to D. similis in all concentrations applied theoretical tributaries. In F1, F2 and F3, the effluent of the system showed little significant acute toxicity to P. subcapitata, P. reticulata, and G. tigrina. F4 in the effluent was significantly toxic to organisms: P. subcapitata, P. reticulata and G. tigrina. The species indicated that the test organisms suitable for toxicity studies of formaldehyde containing wastewater treated by the combined system of the target study. From the results, the combined system, the configuration used in this study was considered appropriate to reduce the toxicity of formaldehyde concentrations present, except for the concentration of 500 mg L-1, toxic to three test organisms, requiring a longer period of adaptation of the system to reduce effluent toxicity / Mestrado / Saneamento e Ambiente / Mestre em Engenharia Civil

M.Sc. / South Africa can be classified as a semi-arid country and the management of its precious water resources is essential. Environmental pollution, caused by the development of industry, technology and informal settlements, threaten the health status of many freshwater ecosystems. The health of all living organisms living in aquatic ecosystems is therefore subsequently affected by this decrease in water quality. The health of an ecosystem is thus often reflected by the health of its fauna. Fish are relatively sensitive to changes in their surrounding environment, including an increase in pollution. Fish health may as a result reflect, and give a good indication of the health status of the aquatic ecosystem in which the fish occurs. The initial toxic effects of the pollution may, however, only be evident on cellular or tissue level before significant changes can be identified in fish behaviour or external appearance. Histological analysis appears to be a very sensitive parameter and is crucial in determining cellular changes that may occur in target organs, including the liver. A histological investigation may therefore prove to be a cost-effective tool to determine the health of fish populations, hence reflecting the health of an entire aquatic ecosystem within a bio-monitoring process. Within the South African context, limited research has been conducted regarding the histology and histopathology of endemic fish species, and its value and effectiveness in aquatic monitoring. The aim of this study was to investigate and validate whether fish liver histology can be used as a monitoring tool, to indicate the health status of an aquatic ecosystem. In order to accomplish this, a preliminary histological study was done on the liver of Clarias gariepinus, a freshwater fish species endemic to the southern African region. Fish were collected in the Rietvlei Dam, Marais Dam and the Palala River, chosen as the three aquatic ecosystems for this study, due to their dissimilar pollution levels. Fish liver samples were fixed in 10% neutrally buffered formalin and prepared for light microscopy analysis using standard techniques for Haematoxylin and Eosin (H & E) staining. From the results obtained during this study, it was concluded that the liver histology of C. gariepinus did appear to be a sensitive monitoring tool of aquatic health. The histological investigation of the fish livers obtained in the Palala River, chosen as an unpolluted site, appeared to be in an overall healthier condition than the liver histology of fish obtained from the two relatively polluted sites, the Rietvlei Dam and the Marais Dam. This conclusion was obtained by means of an objective, quantitative analysis. The histological results in this study were quantified in terms of a histological index. An index value representing the specific histological characteristics of the liver was assigned to each individual specimen indicating either a healthy histological structure (index value of 0-2) or a possible pathological condition (index value of 3-6). According to the quantitative assessment, an average histological index value of 2.5 (indicating a relatively healthy histological condition) was calculated for the unpolluted site while a higher average index value of 3.2 (indicating a pathological condition) were calculated for both the relatively polluted sites. The fish liver histology did therefore reflect the health status of the aquatic ecosystem in which the fish specimen occurred. It was therefore concluded that the liver histology of C. gariepinus seemed to be a sensitive biomarker of environmental pollution, and hence an effective monitoring tool for estimating the health status of an aquatic ecosystem. / Dr. G.M. Pieterse