Um die Effekte von Umweltchemikalien auf Populationen von Fließgewässerorganismen zu untersuchen, sind an der TU Dresden Fließrinnen entwickelt worden. Die Komplexität wurde bewusst reduziert, um die beobachteten Effekte besser kausal analysieren zu können. Nach einer Erweiterung des Nahrungsnetzes um Grazer (Eintagsfliegen-Larven) und der weiteren Optimierung der Methode zur Bestimmung des Aufwuchses (Periphyton) wurden 2 Experimenten mit einem Pflanzenschutzmittel (Fenoxycarb) und einer Industriechemikalie (Bisphenol A) durchgeführt, um die Effekte dieser Chemikalien auf den Aufwuchs, die Eintagsfliegen-Larven Rhithrogena semicolorata und Seratella ignita, sowie Oligochaeten der Art Lumbriculus variegatus zu erfassen. Die Wirkung von Fenoxycarb in 4 Konzentrationen von 0,05 bis 50 µg L-1 wurde über eine Dauer von 101 Tagen untersucht. Auf die physiko-chemischen Parameter, den Aufwuchs und L. variegatus wurden keine Effekte festgestellt. Bei R. semicolorata wurden Effekte auf das Überleben und die Emergenz beobachtet. Für den Endpunkt "Anzahl der toten Larven in der Fließrinne" wurde eine LC50 von 3,3 µg L-1 bestimmt. Die akute Toxizität (48 h LC50) von Fenoxycarb für S. ignita ist größer als 5 mg L-1. Bei Larven von S. ignita wurden 72 Tage nach Applikation Effekte beobachtet werden, die dem Wirkmechanismus von Fenoxycarb entsprechen. In der höchsten Konzentration zeigten ca. 80 % der emergierten Tiere morphologische Abnormalitäten an 4 Segmenten des Abdomens. Die Exposition erfolgte möglicherweise durch an Aufwuchs bzw. Detritus gebundene Substanz oder deren Metabolite, da die Substanz 19 Tage nach Applikation im Wasser nicht mehr nachweisbar war. Im zweiten Experiment wurde Wirkung von Bisphenol A in 3 Konzentrationen von 5 bis 500 µg L-1 (effektiv 0,24 bis 24,1 µg L-1) über eine Dauer von 103 Tagen untersucht. Auf die physiko-chemischen Parameter wurde kein Einfluss festgestellt. Der Aufwuchs in der höchsten Konzentration erreichte nur die Hälfte des Biomasse-Maximums der Kontrolle. Die EC10 beträgt 1,8 und die EC50 21,7 µg L-1 (effektiv). Das Populationswachstum von Lumbriculus variegatus war in den beiden höchsten Konzentrationen im Vergleich zur Kontrolle um ca. 50 % reduziert. Die akute Toxizität (LC50 96 h) für L. variegatus beträgt 5,3 mg L-1. Für das Populationswachstum in den Fließrinnen wurde eine EC10 von 0,11 µg L-1 (effektiv) ermittelt, die um den Faktor 48184 unter der akuten Toxizität liegt. - Anlage: Rohdaten (0,53 MB)- Nutzung: Referat Informationsvermittlung der SLUB"

Manufactured CeO2 nanomaterials (CeO2-MNMs) are used for a wide variety of applications including diesel fuel additives and chemical/mechanical planarization media. To test the effects of CeO2-MNM surface coating charge on to model organism Caenorhabditis elegans, we synthesized 4 nm CeO2 with cationic (DEAE-), anionic (CM-), and neutral (DEX) coatings. In L3 nematodes exposed for 24 hours, DEAE-CeO2 induced lethality at lower concentrations than CM- or DEX-CeO2. Feeding slightly decreased CeO2 toxicity, regardless of coating. In L2 nematodes exposed for 48 hours with feeding, DEAE-CeO2 caused lethality at the lower concentrations as compared to CM- and DEX-CeO2. Sublethal effects were measured by observing reproduction and oxidative/nitrosative protein damage. Low concentrations of DEAE-CeO2 induced similar reductions as CM- and DEX-CeO2 that were two orders of magnitude higher. Using immunochemical slot blots to explore oxidative/nitrosative stress, no treatments produced significant changes in protein carbonyl or 3-nitrotyrosine formation; however, the statistical power of our assay was low. All treatments caused large but not statistically significant increases in protein carbonyl levels. DEAE-CeO2 exposure caused a significant reduction in 4-hydroxy-2-nonenol levels. This research suggests that cationic coatings render CeO2 significantly more toxic to C. elegans than neutral or anionic coatings.

L'objectif de travail a été d'évaluer l'effet de deux types de polluants, le tributylétain (TBT) et les hydrocarbures aromatiques polycycliques (HAPs), sur l'activation de la voie des MAP kinases et sur l'induction de l'apoptose chez deux invertébrés marins, la moule Mytilus galloprovincialis et l'éponge Suberites domuncula. Il a été montré, chez ces deux espèces exposées aux deux composés, une activation systématique de p38 en réponse à toutes les conditions expérimentales testées. JNK est également activée suite à leur exposition au TBT. En revanche, une exposition aux HAPs, dans les conditions expérimentales choisies, induit l'activation de JNK, chez la moule et de ERK, chez l'éponge. En outre, une induction de l'expression de Bcl-xS a été observée chez la moule, protéine impliquée dans la voie intrinsèque de l'apoptose. Chez l'éponge, l'induction de l'apoptose est dépendante de l'activation de la caspase 3 alors que chez la moule, comme chez d'autres bivalves, le processus apoptotique n'est dépendant de la caspase 3 que pour certaines concentrations de polluant. Par ailleurs, l'analyse des échantillons de moules prélevées in situ dans dix neuf stations de la côte adriatique (Croatie), polluées à des degrés divers notamment par le TBT et les HAPs, durant l'hiver et l'été, a montré une activation des trois MAPKs p38, JNK et ERK. Le niveau d'activation est corrélé au degré de pollution et à la température. Pour conclure, ce travail permet de noter l'intérêt de la p38 comme biomarqueur d'exposition et celui de l'apoptose comme marqueur d'effet.

The extensive agricultural usage of organohalogenated pesticides has raised many concerns about their potential hazards especially in the soil environment. Environmental metabolomics is an emerging field that investigates the changes in the metabolic profile of native organisms in their environment due to the presence of an environmental stressor. Research presented here explores the potential of Nuclear Magnetic Resonance (NMR)-based metabolomics to examine the sub-lethal exposure of the earthworm, Eisenia fetida to sub-lethal concentrations of organohalogenated pesticides. Various one-dimensional (1-D) and two dimensional (2-D) NMR techniques were compared in a contact filter paper test earthworm metabolomic study using endosulfan, a prevalent pesticide in the environment. The results determined that both the 1H Presaturation Utilizing Gradients and Echos (PURGE) and the 1H-13C Heteronuclear Single Quantum Coherence (HSQC) NMR techniques were most effective in discriminating and identifying significant metabolites in earthworms due to contaminant exposure. These two NMR techniques were further explored in another metabolomic study using various sub-lethal concentrations of endosulfan and an organofluorine pesticide, trifluralin to E. fetida. Principal component analysis (PCA) tests showed increasing separation between the exposed and unexposed earthworms as the concentrations for both contaminants increased. A neurotoxic mode of action (MOA) for endosulfan and a non-polar narcotic MOA for trifluralin were delineated as many significant metabolites, arising from exposure, were identified. The earthworm tissue extract is commonly used as the biological medium for metabolomic studies. However, many overlapping resonances are apparent in an earthworm tissue extract NMR spectrum due to the abundance of metabolites present. To mitigate this spectral overlap, the earthworm’s coelomic fluid (CF) was tested as a complementary biological medium to the tissue extract in an endosulfan exposure metabolomic study to identify additional metabolites of stress. Compared to tests on the tissue extract, a plethora of different metabolites were identified in the earthworm CF using 1-D PURGE and 2-D HSQC NMR techniques. In addition to the neurotoxic MOA identified previously, an apoptotic MOA was also postulated due to endosulfan exposure. This thesis also explored the application of 1-D and 2-D NMR techniques in a soil metabolomic study to understand the exposure of E. fetida to sub-lethal concentrations of endosulfan and its main degradation product, endosulfan sulfate. The earthworm’s CF and tissue extract were both analyzed to maximize the significant metabolites identified due to contaminant exposure. The PCA results identified similar toxicity for both organochlorine contaminants as the same separation, between exposed to the unexposed earthworms, were detected at various concentrations. Both neurotoxic and apopotic MOAs were observed as identical fluctuations of significant metabolites were found. This research demonstrates the potential of NMR-based metabolomics as a powerful environmental monitoring tool to understand sub-lethal organohalogenated pesticide exposure in soil using earthworms as living probes.

There is relatively little known about the fate of human pharmaceuticals once they are released into the aquatic environment and what adverse impacts these compounds have on exposed aquatic organisms. Both of these factors are essential in defining the potential risk pharmaceuticals pose in the aquatic environment. For this project up to 14 human therapeutic agents were selected as representative compounds to assess both their fate and effects within model aquatic systems. Considering sediments often serve as a repository for aquatic contaminants, the interaction of the selected pharmaceuticals with sediment was assessed. The sorption of the selected pharmaceuticals was found to be highly variable. Furthermore, the solution pH and ionic strength, due to Ca2+, were found to exert a large degree of influence on the extent of sorption observed. These solution parameters, among others, may therefore make it difficult to predict the fate of pharmaceuticals, in terms of their association with sediments, using standardised assessment methods alone. There is an extensive pool of knowledge on pharmaceuticals, in terms of their pharmacological profile, so their distribution within the human body (using the volume of distribution or VD) was compared with their distribution within a sediment / water system (using the partition coefficient or Kd). The correlation between the VD and Kd indicated this relationship provided a reasonable basis for estimating the distribution of drugs within the test sediment / water systems. This finding suggests that further exploration of the use of pharmacological data in understanding the potential fate of pharmaceuticals in aquatic systems is warranted. The extent of the pharmaceuticals respective desorption values was also found to be highly variable within a standard test system. Further analysis on the desorption of carbamazepine, an anti-epileptic drug, was undertaken using an isotopic dilution technique. Observations from the isotopic dilution study indicated that both contact time with sediment and the quality of organic carbon could play an important role in the potential for sediments to irreversibly sorb carbamazepine present in aquatic systems. The desorption hysteresis observed for the other pharmaceuticals also indicates considerable effort is still required to address the issue of whether sediments can be a means of reducing exposure of pharmaceuticals to aquatic organisms (a “sink”) or a means of increasing exposure to sediment-dependent organisms (a “source”). The necessity for further work on investigating the role that sorption with sediments may play in the fate and effects of human pharmaceuticals was highlighted by a series of ecotoxicological assays in both sediment and solution-only systems. Sediment-dwelling freshwater midges, Chironomus tepperi, were exposed to carbamazepine in both short- and long-term assays. Wet weight was found to be significantly reduced during short-term assays, while the development of C. tepperi larvae was found to be significantly inhibited when exposed to spiked sediment, over a longer exposure period. For these assays, the aqueous phase may have been a more important route of exposure of carbamazepine for the midges. This study has indicated that sediments are likely to play an important role in the fate of pharmaceuticals and, subsequently, their effects. However, considerably more effort is required to assess the role sediments have and how this knowledge can be linked with current regulatory ecological risk assessments. / http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1298389 / Thesis (Ph.D.) -- University of Adelaide, School of Earth and Environmental Sciences, 2007

There is relatively little known about the fate of human pharmaceuticals once they are released into the aquatic environment and what adverse impacts these compounds have on exposed aquatic organisms. Both of these factors are essential in defining the potential risk pharmaceuticals pose in the aquatic environment. For this project up to 14 human therapeutic agents were selected as representative compounds to assess both their fate and effects within model aquatic systems. Considering sediments often serve as a repository for aquatic contaminants, the interaction of the selected pharmaceuticals with sediment was assessed. The sorption of the selected pharmaceuticals was found to be highly variable. Furthermore, the solution pH and ionic strength, due to Ca2+, were found to exert a large degree of influence on the extent of sorption observed. These solution parameters, among others, may therefore make it difficult to predict the fate of pharmaceuticals, in terms of their association with sediments, using standardised assessment methods alone. There is an extensive pool of knowledge on pharmaceuticals, in terms of their pharmacological profile, so their distribution within the human body (using the volume of distribution or VD) was compared with their distribution within a sediment / water system (using the partition coefficient or Kd). The correlation between the VD and Kd indicated this relationship provided a reasonable basis for estimating the distribution of drugs within the test sediment / water systems. This finding suggests that further exploration of the use of pharmacological data in understanding the potential fate of pharmaceuticals in aquatic systems is warranted. The extent of the pharmaceuticals respective desorption values was also found to be highly variable within a standard test system. Further analysis on the desorption of carbamazepine, an anti-epileptic drug, was undertaken using an isotopic dilution technique. Observations from the isotopic dilution study indicated that both contact time with sediment and the quality of organic carbon could play an important role in the potential for sediments to irreversibly sorb carbamazepine present in aquatic systems. The desorption hysteresis observed for the other pharmaceuticals also indicates considerable effort is still required to address the issue of whether sediments can be a means of reducing exposure of pharmaceuticals to aquatic organisms (a “sink”) or a means of increasing exposure to sediment-dependent organisms (a “source”). The necessity for further work on investigating the role that sorption with sediments may play in the fate and effects of human pharmaceuticals was highlighted by a series of ecotoxicological assays in both sediment and solution-only systems. Sediment-dwelling freshwater midges, Chironomus tepperi, were exposed to carbamazepine in both short- and long-term assays. Wet weight was found to be significantly reduced during short-term assays, while the development of C. tepperi larvae was found to be significantly inhibited when exposed to spiked sediment, over a longer exposure period. For these assays, the aqueous phase may have been a more important route of exposure of carbamazepine for the midges. This study has indicated that sediments are likely to play an important role in the fate of pharmaceuticals and, subsequently, their effects. However, considerably more effort is required to assess the role sediments have and how this knowledge can be linked with current regulatory ecological risk assessments. / http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1298389 / Thesis (Ph.D.) -- University of Adelaide, School of Earth and Environmental Sciences, 2007

There is relatively little known about the fate of human pharmaceuticals once they are released into the aquatic environment and what adverse impacts these compounds have on exposed aquatic organisms. Both of these factors are essential in defining the potential risk pharmaceuticals pose in the aquatic environment. For this project up to 14 human therapeutic agents were selected as representative compounds to assess both their fate and effects within model aquatic systems. Considering sediments often serve as a repository for aquatic contaminants, the interaction of the selected pharmaceuticals with sediment was assessed. The sorption of the selected pharmaceuticals was found to be highly variable. Furthermore, the solution pH and ionic strength, due to Ca2+, were found to exert a large degree of influence on the extent of sorption observed. These solution parameters, among others, may therefore make it difficult to predict the fate of pharmaceuticals, in terms of their association with sediments, using standardised assessment methods alone. There is an extensive pool of knowledge on pharmaceuticals, in terms of their pharmacological profile, so their distribution within the human body (using the volume of distribution or VD) was compared with their distribution within a sediment / water system (using the partition coefficient or Kd). The correlation between the VD and Kd indicated this relationship provided a reasonable basis for estimating the distribution of drugs within the test sediment / water systems. This finding suggests that further exploration of the use of pharmacological data in understanding the potential fate of pharmaceuticals in aquatic systems is warranted. The extent of the pharmaceuticals respective desorption values was also found to be highly variable within a standard test system. Further analysis on the desorption of carbamazepine, an anti-epileptic drug, was undertaken using an isotopic dilution technique. Observations from the isotopic dilution study indicated that both contact time with sediment and the quality of organic carbon could play an important role in the potential for sediments to irreversibly sorb carbamazepine present in aquatic systems. The desorption hysteresis observed for the other pharmaceuticals also indicates considerable effort is still required to address the issue of whether sediments can be a means of reducing exposure of pharmaceuticals to aquatic organisms (a “sink”) or a means of increasing exposure to sediment-dependent organisms (a “source”). The necessity for further work on investigating the role that sorption with sediments may play in the fate and effects of human pharmaceuticals was highlighted by a series of ecotoxicological assays in both sediment and solution-only systems. Sediment-dwelling freshwater midges, Chironomus tepperi, were exposed to carbamazepine in both short- and long-term assays. Wet weight was found to be significantly reduced during short-term assays, while the development of C. tepperi larvae was found to be significantly inhibited when exposed to spiked sediment, over a longer exposure period. For these assays, the aqueous phase may have been a more important route of exposure of carbamazepine for the midges. This study has indicated that sediments are likely to play an important role in the fate of pharmaceuticals and, subsequently, their effects. However, considerably more effort is required to assess the role sediments have and how this knowledge can be linked with current regulatory ecological risk assessments. / http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1298389 / Thesis (Ph.D.) -- University of Adelaide, School of Earth and Environmental Sciences, 2007

Made available in DSpace on 2016-06-02T19:32:09Z (GMT). No. of bitstreams: 1 5730.pdf: 6957633 bytes, checksum: c45a22d4b0d6a4e3858d4318d496940e (MD5) Previous issue date: 2014-02-07 / Financiadora de Estudos e Projetos / In Brazil and other countries the agrochemical carbofurano is largely used, and can reach freshwaters and cause damages to non-target organisms. Rotifera dominates zooplankton communities of most freshwater ecosystems worldwide, both in number of species and density. In the present work biological and ecotoxicological studies in laboratory were carried out with the species Philodina roseola Ehrenberg, 1830 (Rotifera, Bdelloidea) regarding the main aspects of its biology: life cycle, filtration rates, ingestion and secondary production at 25 ± 1.0 °C, besides testing its sensitivity and performance as a test-organism for ecotoxicological studies. Also, a literature review regarding the use of rotifers as testorganisms in the evaluation of pesticides toxicity in freshwaters was carried out for the last three decades. Experiments were performed aiming to assess filtration and ingestion rates of P. roseola feeding on the microalgae Raphidocelis subcapitata at 7 different concentrations. The individual biomass (μg DW ind-1) and secondary production were determined. The main parameters obtained for P. roseola life cycle were: 23.88 ± 3.82 hours duration of embryonic development; 3.5 days generation time; 22.33 ± 2.29 eggs/female total mean fecundity and 23.0 days maximum longevity. Filtration rates varied between 2.715 and 6.615 ml ind-1d-1. Total mean individual secondary production was 0.285692 ± 0.055185 μg ind-1d-1 from which 73.42 ± 5.62 % was allocated into reproduction. P. roseola was an adequate test-organism for ecotoxicological studies considering the life cycle characteristics and response to the pesticide carbofurano with CE50 48-h values of 13.36 ± 2.63 mg L-1 and 89.32 ± 6.52 mg L-1 for the active ingredient and the commercial product, respectively. It was concluded that P. roseola has a fast development time, high metabolism as related to ingestion and filtration rates, high fecundity and moderate sensitivity to the tested pesticide. Studies on its functional response to other factors combinations and sensitivity to other toxicants should be performed. / No Brasil e em outros países o agrotóxico carbofurano é amplamente utilizado, podendo atingir as águas doces e ocasionar danos a organismos não-alvo. Os rotíferos dominam o zooplâncton da maioria dos ambientes aquáticos em todo o mundo, tanto em número de espécies como em densidade. No presente trabalho, estudos biológicos e ecotoxicológicos em laboratório com a espécie Philodina roseola Ehrenberg, 1830 (Rotifera, Bdelloidea) foram realizados, em relação aos principais aspectos de sua biologia: ciclo de vida, taxas de filtração, ingestão e produção secundária a 25 ± 1,0 °C, além de testar sua sensibilidade e desempenho como organismo-teste para estudos ecotoxicológicos. Realizou-se uma revisão de literatura sobre a utilização de rotíferos como organismos-teste na avaliação da toxicidade de pesticidas em águas doces, para as últimas três décadas. Experimentos foram realizados para determinar as taxas de filtração e de ingestão de P roseola, alimentadas com Raphidocelis subcapitata em 7 concentrações diferentes. A biomassa (μg PS. ind-1) e a produção secundária individual foram determinadas. Os principais parâmetros do ciclo de vida de P. roseola foram: desenvolvimento embrionário de 23,88 ± 3,82 horas; idade da primípara de 3,5 dias; fecundidade total média de 22,33 ± 2,29 ovos/fêmea e longevidade máxima de 23 dias. As taxas de filtração variaram entre 2,715 e 6,615 mL ind-1d-1. A produção secundária total foi de 0, 285692 ± 0,055185 μg ind-1d-1 sendo 84,68 ± 3,65 % desta alocada em reprodução. P. roseola é uma espécie adequada como organismo-teste em estudos ecotoxicológicos considerando-se o conjunto de características de seu ciclo de vida e as respostas ao pesticida carbofurano com valores de CE50 48-h de 13,36 ± 2,63 mg L-1 e 89,32 ± 6,52 mg L-1 para o ingrediente ativo e o produto formulado respectivamente. Concluiu-se que P. roseola tem rápido tempo de desenvolvimento, elevado metabolismo em relação às taxas de ingestão e filtração, elevada fecundidade e moderada sensibilidade ao pesticida testado. Estudos sobre suas respostas funcionais a outras combinações de fatores e sua sensibilidade a outros compostos tóxicos deverão ser realizados.

Submitted by Ronildo Prado (ronisp@ufscar.br) on 2017-08-22T14:00:18Z No. of bitstreams: 1 DissRCG.pdf: 1738048 bytes, checksum: 5fe499e8468dd911a3576a5aaf9afff3 (MD5) / Approved for entry into archive by Ronildo Prado (ronisp@ufscar.br) on 2017-08-22T14:00:27Z (GMT) No. of bitstreams: 1 DissRCG.pdf: 1738048 bytes, checksum: 5fe499e8468dd911a3576a5aaf9afff3 (MD5) / Approved for entry into archive by Ronildo Prado (ronisp@ufscar.br) on 2017-08-22T14:00:33Z (GMT) No. of bitstreams: 1 DissRCG.pdf: 1738048 bytes, checksum: 5fe499e8468dd911a3576a5aaf9afff3 (MD5) / Made available in DSpace on 2017-08-22T14:00:38Z (GMT). No. of bitstreams: 1 DissRCG.pdf: 1738048 bytes, checksum: 5fe499e8468dd911a3576a5aaf9afff3 (MD5) Previous issue date: 2017-03-02 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Nanoparticles (NPs) have been produced on a large scale worldwide for various consumer purposes such as the production of cosmetics, sunscreen, biosensors, human prosthetics and cancer therapy. However, due to its large production, NPs can have water bodies as final destination, where current studies addressing these compounds are not sufficient to estimate the threat that these substances could cause to aquatic organisms. Chronic studies with nano-Fe3O4 are scarce and, to the best of our knowledge, inexistent regarding tropical zooplankton species, although chronic studies are of great importance to predict the effects of the substances because they analyses great part of this organisms life cycle. At present study, we investigated nanoparticles of Fe3O4, to the tropical cladoceran Ceriodaphnia silvestrii using acute toxicity tests (0.00; 0.01; 0.10; 1.00; 10.00 and 100.00 mg L-1) during 48h, and chronic toxicity tests (0.00; 3.125; 6.25; 12.50; 25.00 and 50.00 mg L-1) during 14 days. Characterization of NPs in the exposure medium revealed that they experienced agglomeration and aggregation on a micrometer scale. Results showed non-toxicity of nano-Fe3O4 after 48h of acute exposure (EC5048h > 100.00 mg L-1). ). In chronic tests, treatment of 50 mg L-1 caused significant inhibition of growth and reproduction, affecting the maximum length (inhibited 12.71%), accumulated number of eggs (reduction of 51.99%) and neonates (decrease of 61.37%) per female (Dunnett’s test, p < 0.05). We concluded that nano-Fe3O4, in the 14th day, was toxic to C. silvestrii only at the highest concentration tested (50.00 mg L-1) during this chronic exposure.. The use of nano-Fe3O4 in aquatic environments could be considered safe to this species in concentrations up to 25.00 mg L-1, according to the parameters evaluated. / As nanopartículas (NPs) têm sido amplamente produzidas em larga escala para vários propósitos tais como: produção de cosméticos, protetores solares, biosensores, próteses humanas e tratamento do câncer. No entanto, devido à ampla produção, eventualmente as NPs podem encontrar seu destino final nos corpos d’água, onde os estudos relativos à presença dessas substâncias muitas vezes não são suficientes para estimar os efeitos que as mesmas poderiam causar nos organismos aquáticos. Estudos de toxicidade crônica com nanopartículas de óxido de ferro (nano-Fe3O4) são escassos e, até onde sabemos, inexistentes para cladóceros tropicais, embora avaliações crônicas sejam de grande importância para predição dos efeitos de substâncias, pois abrangem grande parte do ciclo de vida dos organismos. No presente estudo, foram estudadas nanopartículas de Fe3O4 para cladócero neotropical Ceriodaphnia silvestrii, por meio de testes de toxicidade aguda (0,00; 0,01; 0,10; 1,00; 10,00 e 100,00 mg L-1), durante 48 horas, e crônica (0,00; 3,125; 6,25; 12,50; 25,00 e 50,00 mg L-1), durante 14 dias. A caracterização das NPs nos meios de exposição revelou que elas sofreram aglomeração e agregação em escalas micrométricas. Os resultados obtidos apontaram ausência de toxicidade aguda para as nano-Fe3O4 (CE(I)5048h > 100,00 mg L-1). Nos testes de toxicidade crônica, no tratamento de 50,00 mg L-1, houve inibição significativa no crescimento e reprodução, afetando o comprimento máximo (inibição de 12,71%) e o número acumulado de ovos (diminuição de 51,99%) e de neonatas (diminuição de 61,37%) produzidos por fêmea (teste de Dunnett p < 0.05). Concluiu-se que as nano-Fe3O4 apresentaram efeitos crônicos, no 14º dia, para o cladócero C. silvestrii somente na maior concentração avaliada (50,00 mg L-1). O uso de nano-Fe3O4 em ambientes aquáticos pode ser considerado seguro para esta espécie de cladócero tropical, com base nos parâmetros avaliados, até concentrações de 25,00 mg L-1. / CNPq: 132379/2015-5 / FAPESP: 2014/14139-3 / FAPESP: 2016/00753-7

Orientador: Claudia Regina Bonini Domingos / Banca: Lilian Castiglioni / Banca: Fabiano Gazzi Taddei / Resumo: Os quelônios estão entre os grupos de vertebrados com maior risco de extinção, sendo as principais ameaças para as populações, a degradação e poluição ambiental. A espécie Phrynops geoffroanus, popularmente conhecida como "Cágado-de-Barbelas", tem se proliferado em ambiente poluído, sujeita a condições adversas que podem influenciar nos seus hábitos de vida e condições fisiológicas. Estudos que monitorem os efeitos da contaminação ambiental são fundamentais para o conhecimento da biologia da espécie e delineamento de estratégias de conservação efetivas. Deste modo, as análises dos parâmetros hematológicos e bioquímicos mostram-se importantes na avaliação da saúde de animais silvestres e riscos para o animal e ecossistema. O objetivo do trabalho foi verificar a influência do ambiente na fisiologia de uma população de Phrynops geoffroanus por meio da avaliação da capacidade antioxidante e respostas aos estressores ambientais, em comparação com espécimes de local sob condições controladas. Foram avaliadas, por meio do hemograma completo, dosagem de espécies reativas ao ácido tiobarbitúrico (TBARS), ensaio da capacidade antioxidante em equivalência ao Trolox (TEAC) e atividades das enzimas antioxidantes catalase e glicose-6-fosfato desidrogenase (G6PDH), amostras sanguíneas de sessenta espécimes, sendo trinta provenientes do córrego Felicidade, ambiente poluído, no perímetro urbano de São José do Rio Preto-SP; e trinta do criatório "Reginaldo Uvo Leone", Tabapuã-SP, local sob condições controladas, cujas amostras constituem o grupo controle dos experimentos. Houve grande variação nos parâmetros hematológicos de Phrynops geoffroanus de ambiente urbano. Os valores de glóbulos vermelhos e hemoglobina foram significantemente menores que os observados em animais do criatório (p = 0,0004; p = 0,0371, respectivamente)... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The turtles are among the most endangered vertebrates groups, and the main threats to populations are the environmental pollution and degradation. The species Phrynops geoffroanus, popularly known as "Geoffroy's side-necked turtle", has proliferated in polluted environments, subject to adverse conditions that could influence their living habits and physiological conditions. Studies that monitor the effects of environmental pollution are the key to understand the species biology and design effective conservation strategies. Thus, the analysis of hematological and biochemical parameters showed to be important in assessing the health of wild animals and for the animal and ecosystem risks. This work aimed to assess the environmental influence on the physiology of a Phrynops geoffroanus population through the evaluation of antioxidant status and responses to environmental stressors, compared to specimens from a place under controlled conditions. They were evaluated by hemogram, measuring thiobarbituric acid reactive species assay (TBARS), Trolox-equivalent antioxidant capacity evaluation (TEAC) and the activities of antioxidant enzymes, catalase and glucose-6-phosphate dehydrogenase (G6PDH), blood samples of sixty specimens, thirty from the Felicidade stream, polluted environment, within the São José do Rio Preto city, and thirty from the "Reginaldo Uvo Leone" breeding farm, Tabapuã-SP, place under controlled conditions, whose samples constitute the control group of the experiments. There was a wide variation in hematological parameters of Phrynops geoffroanus from the urban environment. The red blood cells and hemoglobin values were significantly less than those observed in animals from breeding farm (p = 0.0004; p = 0.0371, respectively). There was significant increase of thrombocytes (p < 0.0001) and leukocytes (p < 0.0001) to the animals from the Felicidade stream... (Complete abstract click electronic access below) / Mestre