Muitos dos poluentes lançados diariamente no ambiente apresentam capacidade de bioacumulação e potencial altamente tóxico, induzindo danos em diversos níveis de organização. O peixe demersal Cathorops spixii e o pelágico Centropomus parallelus se alimentam de invertebrados bentônicos e pequenos peixes e são importantes itens alimentares para a população em geral. Neste estudo foram avaliadas as respostas citogenotóxicas através da análise de micronúcleos (MN) e anomalias nucleares (AN) em eritrócitos e a bioacumulação de PAHs e organoclorados (em fígado) e metais (em tecido muscular) em 207 exemplares dessas espécies, coletados nos Complexos Estuarinos de Cananéia, Paranaguá e Santos/São Vicente durante o inverno/08 e verão/09. Os tecidos foram extraídos para análises químicas. Na maioria dos casos, os níveis de danos citogenotóxicos obtidos nos exemplares de Paranaguá se colocaram de maneira intermediária, enquanto os da região de Santos estiveram acima dos obtidos nas outras áreas. Ficou evidenciado que os níveis de contaminação destes estuários são capazes de causar danos moleculares nos organismos. C. parallelus respondeu de maneira mais efetiva às análises dos biomarcadores utilizados. A bioacumulação refletiu principalmente a influência de fatores intrínsecos aos organismos e apresentou correlação com os dados citogenotóxicos. A ocorrência de metais e PAHs sobressaíram aos outros compostos. / Several pollutants that are daily discharged in environment are able to bioaccumulate in organism tissues and present highly toxic potential inducing damages in different levels of biological organization. The demersal Cathorops spixii catfish and the pelagic snooks Centropomus parallelus feeds on small fishes and benthic invertebrates and represent an important food source for local populations. In this study the cytogenotoxic responses in erythrocytes were evaluated by micronucleus (MN) and nuclear abnormalities (AN) analysis, and bioaccumulation of PAHs and organochloride compounds (in liver) and metals (in muscle) in 207 organisms of C. spixii and C. parallelus, collected in Cananéia, Paranaguá and Santos/São Vicente Estuarine Systems, during winter/2008 and summer/2009. In the majority of the cases, the cytogenotoxic rates found in Paranaguá were average, while in Santos region rates were higher than the others study areas, evidencing that the pollution levels between both estuaries were high enough to induce genetic damages. C. parallelus are more sensible to biomarkers responses. The bioaccumulation level was influenced by inherent factors from organisms and presented correlation with the cytogenotoxic rates. The occurrence of metals (in muscular tissue) and PAHs (in liver) were more pronounced than other compounds.

Muitos dos poluentes lançados diariamente no ambiente apresentam capacidade de bioacumulação e potencial altamente tóxico, induzindo danos em diversos níveis de organização. O peixe demersal Cathorops spixii e o pelágico Centropomus parallelus se alimentam de invertebrados bentônicos e pequenos peixes e são importantes itens alimentares para a população em geral. Neste estudo foram avaliadas as respostas citogenotóxicas através da análise de micronúcleos (MN) e anomalias nucleares (AN) em eritrócitos e a bioacumulação de PAHs e organoclorados (em fígado) e metais (em tecido muscular) em 207 exemplares dessas espécies, coletados nos Complexos Estuarinos de Cananéia, Paranaguá e Santos/São Vicente durante o inverno/08 e verão/09. Os tecidos foram extraídos para análises químicas. Na maioria dos casos, os níveis de danos citogenotóxicos obtidos nos exemplares de Paranaguá se colocaram de maneira intermediária, enquanto os da região de Santos estiveram acima dos obtidos nas outras áreas. Ficou evidenciado que os níveis de contaminação destes estuários são capazes de causar danos moleculares nos organismos. C. parallelus respondeu de maneira mais efetiva às análises dos biomarcadores utilizados. A bioacumulação refletiu principalmente a influência de fatores intrínsecos aos organismos e apresentou correlação com os dados citogenotóxicos. A ocorrência de metais e PAHs sobressaíram aos outros compostos. / Several pollutants that are daily discharged in environment are able to bioaccumulate in organism tissues and present highly toxic potential inducing damages in different levels of biological organization. The demersal Cathorops spixii catfish and the pelagic snooks Centropomus parallelus feeds on small fishes and benthic invertebrates and represent an important food source for local populations. In this study the cytogenotoxic responses in erythrocytes were evaluated by micronucleus (MN) and nuclear abnormalities (AN) analysis, and bioaccumulation of PAHs and organochloride compounds (in liver) and metals (in muscle) in 207 organisms of C. spixii and C. parallelus, collected in Cananéia, Paranaguá and Santos/São Vicente Estuarine Systems, during winter/2008 and summer/2009. In the majority of the cases, the cytogenotoxic rates found in Paranaguá were average, while in Santos region rates were higher than the others study areas, evidencing that the pollution levels between both estuaries were high enough to induce genetic damages. C. parallelus are more sensible to biomarkers responses. The bioaccumulation level was influenced by inherent factors from organisms and presented correlation with the cytogenotoxic rates. The occurrence of metals (in muscular tissue) and PAHs (in liver) were more pronounced than other compounds.

Les métaux sont des éléments chimiques ubiquitaires, naturellement présents dans notre environnement et utilisés dans de nombreux secteurs d’activité tels que, l’aérospatial, la cosmétologie ou l’industrie pharmaceutique. De nombreux travaux montrent qu’ils sont susceptibles d’être à l’origine de diverses pathologies. Toutefois, la diversité et les modalités des études réalisées rendent difficiles la comparaison de leurs effets et mécanisme d’action. Dans ce contexte, ce travail concerne l’étude de la cyto-génotoxicité du cadmium, du nickel et de l’aluminium, sur un même modèle cellulaire, le fibroblaste cutané humain. Leur cytotoxicité est évaluée en étudiant leur effet sur la bioénergétique cellulaire par microcalorimétrie et, leur effet sur la viabilité cellulaire est mesuré par des techniques colorimétriques conventionnelles. Leur génotoxicité est déterminée par des techniques spécifiques que sont le test des comètes et des micronoyaux. De plus, une approche de leur interaction avec l’ADN est réalisée par microcalorimétrie. Les résultats montrent que la cytotoxicité du cadmium est supérieure à celle du nickel, elle-même supérieure à celle de l’aluminium. Seuls le cadmium et le nickel sont génotoxiques à pH7 principalement en induisant un effet aneugène. Leur interaction est de type électrostatique anti-coopérative avec les groupements phosphate de l’ADN. Si l’aluminium à pH7, n’exerce pas d’effet génotoxique, son interaction avec l’ADN à pH acide est comparable à celle du cadmium et du nickel. Ce résultat singulier lié à la valeur du pH suggère l’importance de la prise en compte de la spéciation des métaux pour l’étude de leurs effets aussi bien in vitro qu’in vivo / Metals are ubiquitous chemical elements naturally present in our environment and used in many field, like aerospace, cosmetology or pharmaceutical industries. Many works show that metals are involved in diverse diseases. However, the way these studies are led, make the comparison of their effects and mechanism of action delicate. In this context, this work studies the cyto-genotoxicity of cadmium, nickel and aluminum on a single cellular model: normal human dermal fibroblasts. Cytotoxicity is first evaluated by the cell bioenergetics study thanks to microcalorimetry technics, and then the effect on cell viability is measured by conventional colorimetric techniques. Genotoxicity is evaluated by specific technics which are comet and micronuclei assays. Furthermore, thermodynamic properties of the interaction between metals and DNA are determined tanks to microcalorimetry measures. Results show that cadmium cytotoxicity is higher than nickel, itself higher than aluminum. Cadmium and nickel are the only ones genotoxic, they mostly induce aneugenic effects. They present an electrostatic anti-cooperative interaction with DNA phosphate groups. If, at pH 7, aluminum does not induce genotoxicity, his interaction is comparable to cadmium and nickel at acidic pH. This unusual result, related to pH value, highlights the importance of the speciation determination when metal effects are studied, as well in vitro as in vivo

Submitted by isabela.moljf@hotmail.com (isabela.moljf@hotmail.com) on 2017-08-21T15:13:55Z No. of bitstreams: 1 gabriellerabeloquadra.pdf: 2085169 bytes, checksum: 5108ddde0dcf7f981be518facd560aa1 (MD5) / Rejected by Adriana Oliveira (adriana.oliveira@ufjf.edu.br), reason: on 2017-08-24T11:31:31Z (GMT) / Submitted by isabela.moljf@hotmail.com (isabela.moljf@hotmail.com) on 2017-08-24T13:21:00Z No. of bitstreams: 0 / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-08-30T12:29:16Z (GMT) No. of bitstreams: 0 / Made available in DSpace on 2017-08-30T12:29:16Z (GMT). No. of bitstreams: 0 Previous issue date: 2017-02-24 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / - / Aquatic ecosystems provide many services to humanity, despite this; water pollution is one of the most serious environmental problems worldwide. Reservoirs, including ones used for water supply, receive from tributaries, or directly, several effluents from human activities that contain a pool of pollutants. Reservoir sediments work as sink or source for pollutants depending on environmental conditions. Therefore, pollutants present in these aquatic compartments can return to the water column or transfer through the food chain, where they can be toxic to biota and even to humans. Contaminants in the environment can cause mutagenic effects that can accumulate in DNA and harm a whole population. Then, genotoxicity tests, such as Allium cepa assay, may be used to evaluate the extent of environmental pollution, since synergistic effects might occur and physicochemical analysis just provide the presence of pollutants. Studies focusing on the presence of chemical compounds in reservoirs sediments and their toxicity are crucial. In this context, the study aimed to investigate contamination in sediments by metals in Brazilian reservoirs, as well as potential ecological risk and potential to cause cytogenotoxicity in A. cepa. Copper, chromium, cadmium, lead, zinc and iron were measured in sediment samples from six Brazilian reservoirs. Besides that, the surface layer of sediment was submitted to a resuspension simulation to the water column, and sediment solution was submitted to Allium cepa assay and metals analysis. Our findings showed that these reservoirs seem to be influenced by agricultural, industrial and domestical effluents because of the presence of copper, cadmium, and zinc above threshold effect levels in some samples and a potential ecological risk was observed. More than that decrease mitotic index and increase chromosomal aberrations in all treatments (except Furnas reservoir) showed cytogenotoxic effects. The presence of metals and other possibly inorganic and organic pollutants may be answerable for cytogenotoxic effects observed. In this sense, just chemical analyses were not enough to evaluate the extent of environmental pollution in sediments and its impact. We need to use more tools combined with chemical analysis to provide a better understand of pollution in aquatic ecosystems. It is important to implement law and regulations that are more efficient, intensive monitoring, sewage treatment and reforestation of riparian zones to protect these systems, including preventing public health problems.