Suite à l’utilisation massive et peu contrôlée des pesticides au LIBAN et conformément auxexigences des législations fixées par les réglementations nationales, européennes etinternationales sur la qualité de l’eau, des programmes de surveillances nationaux ont étéélaborés afin d’évaluer la qualité de l’eau dans les milieux aquatiques libanais et de jauger lesimpacts écologiques et sanitaires liés à la présence éventuelle de pesticides dansl’environnement au Liban.Dans le cadre de ces programmes de surveillance, des prélèvements périodiques ponctuelssont réalisés mais, le suivi permanant dans le temps d’une contamination étendue est trèsdifficile ce qui impose alors la multiplication des prélèvements dans le temps et dansl’espace. L’apparition récente des échantillonneurs intégratifs comme alternativesintéressantes aux techniques d’échantillonnage déjà existantes semblent relativement plusefficaces et mieux représentatifs du point de vue économique et environnemental. Ilspermettent d'effectuer un suivi moyenné sur de longues périodes d'observation allant dequelques jours à plusieurs semaines associé à une simplicité d'usage et une réduction descoûts.Le POCIS (Polar Organic Chemical Integrative Sampler) est le type d’échantillonneur adoptédurant nos travaux de thèse afin d’étudier l’applicabilité de ces POCIS au dosage des résidusde pesticides dans les milieux aquatiques libanais. Cent-neuf molécules appartenant àdifférentes familles de pesticides fréquemment utilisés par les agriculteurs libanais ont étéretenues pour l’étude. Les cinétiques d’adsorption des molécules sur les POCIS et celle de ladésorption des composés références de performance « PRC » ont été suivies par calibrationin-situ ou au laboratoire soit en flux statique ou en flux continu sous différentes conditionsayant une influence sur la rétention des pesticides.Le coefficient d’échantillonnage Rs (L.j-1) spécifique à chaque molécule, nécessaire au calculde la concentration moyenne dans le milieu d’exposition du POCIS, a été déterminé dans lesdivers milieux d’étude : Eau minérale, eau de robinet et eau de rivière. Les cinétiquesd’adsorption des molécules ont également été élaborées afin d’évaluer la durée optimaled’implantation dans les différents milieux aquatiques.Après validation du système d’échantillonnage au laboratoire, son efficacité a été vérifiée surle terrain, les POCIS ont été testés in-situ sur divers sites appartenant aux différentes régionsagricoles libanaises (Estuaire de la rivière Ibrahim, Lac Qaraoun, et Rivière Hasbani). Lesconcentrations moyennes de la totalité des pesticides ciblés ont été estimées et leurs valeursont été comparées avec celles obtenues par prélèvements actifs. Cependant, pour le futur, desétudes élaborées devraient être entreprises afin de couvrir la majorité des molécules activesde pesticides employés au Liban; il faudrait également essayer d’améliorer la reproductibilitédes POCIS pour les analyses quantitatives par l’incorporation de nouveaux composésréférences de Performance (PRC) ou par calibration in-situ systématique pour les différentssites étudiés. / Following the massive uncontrolled use of pesticides in Lebanon and to satisfy therequirements of legislative frameworks and directives concerning water quality, nationalmonitoring programs have been developed in order to evaluate the water quality in theaquatic Lebanese media and to evaluate the environmental and health impacts associated withthe presence of these nominated pesticides in the Lebanese aquatic environment.In this context, monitoring programs rely on collecting discrete grab, spot or bottle samplesof water at a given time providing only a snapshot of the levels of pollutants at the time ofsampling. However, the continuous monitoring using active sampling of this widespreadcontamination is very difficult requiring the increase of sampling frequency which iseconomically, logistically and spatially difficult. Wherefore, the integrative samplers arerecently developed as alternative approach to the existing sampling techniques to berelatively more effective and more representative economically and environmentally. Theycan perform an averaged follow-up over long observation period from a few days to severalweeks associated with ease of use and low costs.The POCIS (Polar Organic Chemical Integrative Sampler) is the type of sampler adoptedduring our thesis in order to study the applicability of this device to the evaluation ofpesticide residues levels in the Lebanese aquatic environments. One hundred nine moleculesbelonging to different families of commonly used pesticides by Lebanese farmers wereselected for the study. The kinetic adsorption constants of targeted pesticides and the kineticdesorption constants of Performance Reference Compounds "PRC" were estimated by POCISin-situ or laboratory (static or continuous flow) calibrations under different conditionsaffecting pesticides retention over POCIS receiving phase.To calculate the average concentration in the exposure media, the sampling rate (L/day),specific to each target pesticide was determined in different water studies: mineral, tap andriver water. The kinetic adsorption constants of molecules have also been determined toassess the optimal deployment duration in different aquatic environments.After validation of the sampling system in the laboratory, its effectiveness is tested in field.POCIS were tested in-situ at various sites belonging to different Lebanese agriculturalregions (Ibrahim Estuary River, Qaraoun Lake and Hasbani River). The mean concentrationsof total targeted pesticides were estimated and their values were compared with thoseobtained with active samples. However, further challenges are to cover the majority of activemolecules of pesticides used in Lebanon and to improve the reproducibility of these POCISfor quantitative analysis by incorporating new Performance Reference Compounds (PRC) orextending the implementation of in-situ calibration.

La présente thèse a pour objectif d'étudier l'impact des dynamiques urbaines sur le niveau de contamination de l'environnement aquatique par les micropolluants. Le cas de la ville de Yaoundé (Cameroun) a été abordé à travers l'étude de la contamination du lac Municipal, situé à l'aval d'un petit bassin versant, et à proximité des centres administratif et commercial où se concentre une part importante de l'activité urbaine. L'approche basée sur l'analyse de contaminants persistants (ETM - Cd, Cu, Pb, Zn, PCB, HAP, nonylphenol - NP, parabènes - MeP, triclosan - TCS) dans des carottes datées de sédiments a été utilisée. Les ETM ont été extraits des sédiments par minéralisation partielle en milieu acide et à chaud, et analysés par ICP AES. Les micropolluants organiques ont été analysés par GC/MS (HAP, PCB, NP), et par LC/MSMS (parabènes, TCS) après extraction assistée par microondes et purification sur colonne de silice ou sur cartouche OASIS® HLB. L'analyse des parabènes et du TCS, des micropolluants émergeants, a conduit à la mise au point d'un protocole analytique. Les informations sur le fonctionnement urbain du bassin versant ont été obtenues grâce à une recherche documentaire depuis la création du lac en 1952 à 2010, et à des enquêtes effectuées auprès des ménages et des commerces. L'analyse des carottes a permis de retracer les apports en micropolluants organiques et métalliques depuis la création du lac Municipal en 1952. Trois périodes ont été définies en fonction de l'évolution des concentrations :• 1952 – 1964 - les concentrations en micropolluants varient peu, et sont généralement inférieures ou de l'ordre des limites de quantification. • 1964 – 1991 - les concentrations en micropolluants augmentent. • 1991 – 2010 – les concentrations de Cd, de Zn et de PCB cessent d'augmenter après 1991, et restent stables jusqu'en 2010. Les concentrations de Cu et de Pb augmentent jusqu'en 2010. La concentration des HAP est stable de 1991 à 2000, et augmente de nouveau jusqu'en 2010. Les concentrations les plus élevées de NP et de MeP sont mesurées à partir de 2000. En termes de flux, les pics ont été mesurés en 1991 pour les PCB, le Cd, le Pb et le Zn, en 2003 pour le NP et en 2010 pour les HAP, le Cu et le MeP. La période couvrant la crise économique de 1991 à 2000 est visible sur les profils de flux de tous les micropolluants. Ils sont stables pendant cette période et repartent à la hausse à partir de 2000 à l'exception des flux de PCB et de Cd. L'étude des concentrations et des flux de contaminants dans les sédiments du lac Municipal fait apparaître trois catégories de contaminants : le premier groupe formé par les PCB, le Cd, et le Zn est lié à la construction. Le second groupe formé par le Cu, le Pb et les HAP est lié au transport automobile. Le dernier groupe comprenant le NP et le MeP est lié aux nouveaux modes de consommation des populations. Contrairement au premier groupe de contaminants, les deux derniers groupes illustrent une contamination à l'échelle de la ville. De faibles concentrations ne présentant pas de risques écotoxicologiques ont été mesurées par rapport à d'autres régions du monde, à cause de la fonction principalement résidentielle du bassin versant et de son occupation par une population peu aisée. La présence du marécage situé en amont du lac a également un impact sur les niveaux de concentration. Des concentrations plus élevées que dans le lac y ont été mesurées, ce qui indique son rôle de rétention des contaminants / The aim of this study was to analyse the impact of urban dynamics on the receiving aquatic environment in tropical African conditions to better understand African environmental problems, often left aside by the research. As study site was chosen the upper part of the Mingoa watershed, one of the small and highly urbanized watersheds of Yaoundé city (Cameroon). The history of the impact was studied through the analysis of persistent and emerging pollutants in dated sediment cores (Cd, Cu, Pb, Zn, PCB, PAH, nonylphenol, parabens and triclosan), and the evolution of the watershed urban development. For trace elements analysis, sediment samples were digested with repeated additions of nitric acid (HNO3) and hydrogen peroxide (H2O2), and analysed ICPAES (inductively coupled plasma atomic emission). Organic contaminats were analysed by GC/MS (HAP, PCB, NP), and by LC/MSMS (parabens, TCS) after microwave extraction and purification on silica gel or OASIS HLB cartridges. A new method was developed for parabens and triclosan analysis in sediments. Informations about the Mingoa river watershed urban development from 1952 when the Municipal Lake was created to 2010 were obtained after a documentary research and local surveys (population and small businesses).The input of pollutants was traced from 1950 to 2010. Three periods were identified in sediment cores according to contaminants levels:• 1952-1964: contaminants concentrations were constant, and usually smaller than quantification limits. The watershed was not very urbanised during the last decade of the colonisation. The country independence was obtained in 1960.• 1964-1991: contaminants concentrations increased. The post colonial period is characterised by population growth and infrastructures development.• 1991-2010: concentrations of Cd, Pb, Zn and PCB stopped to increase after 1991 and remained constant until 2010. This period is characterized by the economic crisis (from the end of 80's to the end of 90's) with no investment in infrastructures. Sources analysis indicated that these contaminants were emitted by building activities. Cu and Pb concentration increased until 2010. PAH concentration remained constant between 1991 and 2000, and increased until 2010. A correlation was observed between Cu, Pb and PAH levels and traffic development in Yaoundé city. Cu and Pb were linked to the car fleet. Pb was also liked to gasoline use while PAH were linked to diesel use. Officially, Pb is no more used in gasoline since 2005. But that stop was not identified in our study. After 2005, we suggested that either it was too early to observe that stop, or another source of Pb could be the recycling of car batteries. Concerning PAH, ratios analyses indicated diesel as a possible source. The highest concentrations of nonylphenol and methylparaben were observed after 2000 due to an increase of the house and personal care products market. Contaminants fluxes were also analysed. Maxima were measured in 1991 for PCB, Cd, Pb and Zn, in 2003 for NP and in 2010 for PAH, Cu and MeP. Between 1991 and 2000, during the economic crisis, fluxes were constants. After 2000, fluxes increased again except for PCB and Cd.Contaminants levels observed in the Municipal Lake sediments were lower than in Western countries, and did not attain the limits set by Environmental protection agencies. This is mainly due to the residential function of the watershed, and the poor economic level of its population. We observed that the presence of a marsh upstream the lake also tempers the impact of the watershed on the lake ecosystem, because higher concentrations were mesasured in general

L’étude historique des pratiques de pêche à la ligne représente un champ de recherche privilégié pour l’utilisation conjointe du social et de l’environnemental. Dans les années 1960 les pêcheurs à la ligne font preuve d’une véritable conscience écologique. Mais cet état de fait n’est pas du « donné » mais du « construit ». La question centrale consiste donc à se demander si un siècle avant l’apparition de l’écologie politique en France, il y a eu une sensibilisation aux problèmes environnementaux par la pratique d’une activité qui met les citoyens aux prises avec le problème de la qualité de leur environnement proche ? Entre le deuxième tiers du XIXe siècle et les années 1940, la pêche à la ligne a évolué : d’une pratique élitiste à une activité de plus en plus populaire. Dans cette évolution, le rôle des hommes et des femmes et des différentes catégories socio-économiques a varié selon les époques et les régions. Les facteurs, les rythmes et la géographie de la prise de conscience des pêcheurs à la ligne de la nécessité de protéger leur environnement sont différents selon les espaces envisagés. Certaines régions, telles que le nord de la France, ont connu un développement précoce de la pêche à la ligne. Cette multitude de réseaux sociaux a donné naissance à un nouveau rapport des hommes à leur environnement, doublé de sociabilités inédites. / By the 1960s, anglers in France had come to display a real environmental consciousness. The aim of this thesis is to show this consciousness had a long history. Anglers in France, a century before the rise of political ecology, exhibited a growing sensibility to environmental problems that came directely from their experiences of the quality of their surroundings as they fished. In this thesis, I show that between 1829 and 1941, the practise of angling evolved from an elitist to a more working-class form of leisure. I also examine how the respective roles of men and women of different social classes changed over time and acoording to place. In addition, I explore the factors, rhythms and geography of this new environmental awareness. It gave rise to some unexpected developments with, for example, the working classes playing a major role in the movement of the protection of nature in France.

The discovery of antibiotics has been considered as one of the most remarkable scientific accomplishments of the last century. However, the extensive usage of antibiotics has led to the rapid emergence of antibiotic resistance genes (ARGs) and antibiotic resistant bacteria (ARB), which have been recognized as one of the biggest threats to human and environmental health. While ARGs and ARB are ubiquitous in diverse environments, aquatic environments play a particularly crucial role in their prevalence and dissemination. Furthermore, the microbial complexity and various pollutants persisting in aquatic environments significantly contribute to the evolution and spread of ARGs and ARB. However, the knowledge regarding the distribution pattern of ARGs on a large scale, as well as the interaction between microbial community, specific pollutants, and ARGs and ARB, is currently limited. In this study, I conducted systematic work at multiple scales, to fill crucial knowledge gaps that could support the future management of the spread of antimicrobial resistance. In particular, on the ecosystems level I depict the biogeographical patterns of ARGs in freshwater reservoirs, on the community level I explored the selection patterns of combinations of antibiotics on multidrug resistant strains in complex community context, and finally, on the population level I investigated the impact of cigarette smoke, and waste products on the dissemination of ARGs. In my first study, samples were collected from 24 freshwater reservoirs across southeast China and the biogeographical patterns of bacterial communities and ARG profile were characterized using 16S rRNA gene high-throughput sequencing and high-throughput-quantitative PCR. A distance-decay pattern for both, microbial communities and ARG profiles, were observed. However, larger differences between reservoir ARG profiles than microbial community compositions were detected. Further, I found that the biogeographical patterns of bacterial communities were simultaneously driven by stochastic and deterministic processes, while ARG profiles were not explained by stochastic processes, and the relationship between bacterial communities and ARG profiles was weak. In summary, this study indicated a decoupling of bacterial community composition and ARG profiles in inland waters under relatively low-human-impact at a large scale. In a second study, the selection dynamics for multidrug resistance between isogenic pairs of E. coli strains under exposure to multiple selective agents in the absence and presence of the microbial community were investigated using microcosm experiments. The presence of the community significantly decreased the selection for multidrug resistant strain under exposure to a single antibiotic. While pressure through the second antibiotic significantly decreased the activity and diversity of the community, its ability to reduce selection was consistently maintained at levels comparable to those recorded in the absence of the second antibiotic. This indicates that the observed effects of community context on selection dynamics are rather based on competitive or protective effects between the focal strains and a small proportion of bacteria within the community, than on general competition for nutrients. Last but not least, the effect of cigarette-derived pollutants on the proliferation of ARGs was explored using multifaced approaches. Cigarette smoke condensate in an artificial lung sputum medium significantly elevated the transfer rates of a multi-drug-resistance encoding plasmid between Pseudomonas strains. The overproduction of reactive oxygen species (ROS) as part of the bacterial stress response was directly connected to the increasing transfer rates. Similarly, cigarette ash leachate in an environmental medium significantly increased the plasmid transfer rates, and overproduction of ROS was equally detected. Furthermore, used cigarette filters with entrapped toxicants were submerged in a wastewater stream and colonized by distinct microbial communities compared to those colonizing unused control filters. The microbial communities colonizing used cigarette filters were significantly enriched in AMR, potential pathogenic bacteria and mobile genetic elements. Overall, the insights gained within this thesis into the spread of AMR at multiple scales constitute a valuable contribution to support future management and monitoring of ARGs in diverse ecosystems.

Chaoborus Lichtenstein (Diptera: Chaoboridae) é um gênero de mosquitos com 44 espécies descritas, das quais 13 ocorrem na região Neotropical. Os adultos são frágeis e delicados, às vezes pouco pigmentados variando entre esbranquiçados, amarelados, acastanhados e acinzentados, sendo conhecidos em países anglófonos como \"phanton midges\". Possuem dimorfismo sexual facilmente reconhecido, pois os machos possuem corpos alongados e transparentes, pedicelos largos e antena plumosa e as fêmeas são menores e mais robustas, devido à presença de ovos em seu abdome, pedicelos globosos, pequenos e antenas verticiladas, com poucas cerdas. Os últimos estudos sobre as espécies neotropicas remontam da década de 1950, as descrições, chaves de identificação e pontos de ocorrência são desatualizados e pouco informativos, motivando o desenvolvimento desta revisão taxonômica. Estágios imaturos de caoborídeos, especialmente as larvas planctônicas, são conhecidas pelos hábitos predatórios na coluna dágua onde fazem migração vertical, agindo no controle populacional das presas em ambientes aquáticos lênticos - de poças a reservatórios. Neste estudo, quatro espécies novas foram descritas, 13 espécies são redescritas e ilustrações do abdome, tórax, terminália masculina, habitus de fêmeas e machos são apresentadas. Mapas de distribuição para cada espécie e uma chave de identificação foram também atualizados. / Chaoborus Lichtenstein (Diptera: Chaoboridae) is a genus of midges with 44 known species, of which only 13 ocurs in Netropical Region. The adults are very delicate and fragile, usualy whitish, yellowish or brownish to grayish, known in Anglophone countries as phantom midges. The sexual dimorphism is easily recognized, as males have long body, transparent, enlarged globular pedicel, plumose antenna while females are shorter, broad, because of the eggs in your abdome, have small globular pedicel and antenna merely setose. The last studies about the Neotropical species are from the 50\'s and the descriptions, identification keys and geographic records are not informative, motivating this taxonomic revision. Immature stages of chaoborids, especially the planktonic larvae, are known for predatory habits in the water column where they migrate vertically, acting on the population control of prey in lentic aquatic environments - from pools to reservoirs. In this study, four new species are described, 13 species are redescribed and ilustrations of abdomen, thorax, male terminalia, habitus of male and female are presented. Distribution maps of each species and an identification key were updated.

O consumo de moluscos bivalves pode representar sérios riscos à saúde pública, pois refletem diretamente as condições do meio ambiente. Desta forma considera-se de extrema importância o consumo de mexilhões livres de contaminação. Esta pesquisa objetivou estudar a qualidade microbiológica das águas e mexilhões de três pontos de cultivo do município de Ubatuba, SP, a saber: Engenho da Almada, Barra Seca e Costão do Cedro em um período compreendido entre novembro de 2002 e março de 2003, totalizando 5 coletas mensais. Analisou-se na água: Bacillus cereus, Clostrídios Sulfito Redutores, Aeróbios Mesófilos, Staphylococcus aureus, Coliformes totais e fecais, Enterococos e Salmonella. Nos mexilhões foram analisados os mesmos microrganismos citados para água mais o Clostridium perfringens. Os resultados encontrados tanto para as análises de água como dos mexilhões foram satisfatórios, condizentes com a legislação brasileira em vigor, salvo a coleta do mês de março, do cultivo da Barra Seca, onde a média dos valores encontrados para coliformes fecais na água (5,7x101 NMP/100mL) foi superior ao recomendado pela legislação sendo detectado também neste mesmo cultivo e mês, presença de Salmonella em 25 g nas amostras de mexilhões. Mesmo que as contagens de S. aureus e B. cereus na carne estejam de acordo com a legislação em vigor, cuidados devem ser tomados quanto ao armazenamento e a forma de consumo. Averiguou-se a intensidade de interferências sazonais na contagem microbiana na água e constatou-se que a tábua de marés e o índice de insolação diária tiveram uma correlação negativa baixa, ao contrário do índice pluviométrico que apresentou correlação positiva alta. / The consumption of bivalve mollusks can represent serious risks to the public health, because they reflect the conditions of the environment directly. This way it is considered of extreme importance the consumption of mussels without contamination. This work aims of studing the water and mussels microbiology quality from three different seafood farms in Ubatuba, SP, to know: Engenho da Almada, Barra Seca and Costão do Cedro from November 2002 to March 2003, totaling five monthly. It was analyzed in the water: Bacillus cereus, Total Clostridia, Aerobic Mesophilic, Staphylococcus aureus, total and fecal coliforms, Enterococci and Salmonella. In the mussels the same microorganisms were analyzed mentioned for water more Clostridium perfringens. The results found in the water and in the mussels were satisfactory, suitable with the Brazilian legislation, except for the sample at Barra Seca’s beach, in March. The average of the values found at that place for fecal coliformes in the water was higher (5,7x101 MPN/100mL) than the recommended by the legislation. Even in this collection, it was also detected Salmonella in 25 g of mussels. Even if the counts of S. aureus and B. cereus in the mussesls are in agreement with the legislation in vigor cares they should be taken with relationship to the storage and the consumption form. The intensity of seasonal interferences was discovered in the microbial count in the water, in which was verified that the board of tides and the index of daily heatstroke had a low negative correlation unlike the index pluviometric it presented high positive correlation

A água constitui um dos compostos de maior distribuição e importância na crosta terrestre. Sua importância para vida está no fato de que nenhum processo metabólico ocorre sem a sua ação direta ou indireta. Entre os vários compostos contaminantes dos ambientes aquáticos, os hormônios, estrógenos naturais e sintéticos, devem ser vistos com uma maior importância, devido a sua persistência no ambiente. O 17α-etinilestradiol (EE2) é um hormônio sintético utilizado na formulação de contraceptivos orais, transdérmico e injetáveis. O presente estudo tem como objetivo analisar o efeito do hormônio sintético 17α-etinilestradiol sobre a biologia do invertebrado aquático Chironomus sancticaroli analisando três gerações do ciclo de vida da espécie. Nos experimentos foram utilizados areia fina comum (lavada em água corrente, seca em estufa a 60ºC e levada a mufla por 4 horas a 560ºC) e água deionizada (condutividade entre 25-55 μS.cm-1, dureza entre 12 e 16 mg.L-1 para CaCO3, pH entre 6,5 a 7,5). Foram realizadas 4 réplicas utilizando-se potes de 2 litros para cada concentração do hormônio e para o controle. Para os testes, foram colocadas 15 larvas, contendo 60 g de areia de cultivo e 240 ml de solução contendo 17α-etinilestradiol (na proporção 1:4, sedimento-solução) nas concentrações de 50; 100; 200; 400; 800 e 1600 μg.L-1, e fotoperíodo de 12h luz/ 12 h escuro e com temperatura de 22 a 26ºC. Os testes agudos foram realizados utilizando-se larvas de IV ínstar sem aeração e os testes crônicos foram realizados utilizando-se larvas de I ínstar com aeração. Os organismos foram alimentados com 5 ml de uma solução contendo 1 litro de água deionizada e 5,0 g de ração para peixe triturada (TetraMin®). O teste realizado foi estático, ou seja, a solução não era trocada do início ao fim do teste de cada geração F1, F2 e F3. Em testes agudos (96h) os resultados mostraram que o composto em estudo não apresenta toxicidade. Nos testes crônicos apenas a terceira geração mostrou uma baixa sobrevivência (43,3 a 56,6%) indicando toxicidade do composto ao organismo-teste, o que foi confirmado pelo teste ANOVA one-way com p ≤ 0,05. O tempo de emergência do organismo na terceira geração foi de 22 dias, havendo um atraso de cinco dias em comparação aos demais tratamentos, indicando que o composto testado pode influenciar no tempo de desenvolvimento do organismo-teste. Na análise da fecundidade potencial, os testes estatísticos indicaram haver uma diferença significativa entre os tratamentos e o controle somente na terceira geração, o que se pode inferir que o composto testado interfere na fecundidade potencial do Chironomus sancticaroli. Não foram encontradas deformidades bucais nas larvas nas três gerações analisadas. Para tanto, faz-se necessários estudos posteriores, visando um número maior de organismos (n ≥ 100) em um número maior de gerações, para que os resultados sejam mais conclusivos no que diz respeito a interferência do composto testado sobre a biologia do Chironomus sancticaroli. / Water is one of the compounds of great distribution and importance in the Earth\'s. Its importance to life lies in the fact that no metabolic process occurs without its direct or indirect action. Among the various contaminating compounds in aquatic environments, hormones, natural and synthetic estrogens, should be viewed with great importance because of their persistence in the environment. 17α-ethinylestradiol (EE2) is a synthetic hormone used in the formulation of oral, transdermal, and injectable contraceptives. The present study aims to analyze the effect of the synthetic hormone 17α-ethinylestradiol on the biology of the aquatic invertebrate Chironomus sancticaroli analyzing three generations of life cycle. In the experiments, common fine sand was used (washed with deionized water, oven dried at 60ºC and muffled for 4 hours at 560ºC) and deionized water (conductivity between 25-55 μS.cm-1, hardness between 12 and 16 mg.L-1 for CaCO3, and pH between 6.5 to 7.5). Four replicates were performed using 2-liter pots for each concentration of the hormone and for the control. For the tests, 15 larvae, containing 60 g of sand and 240 ml of solution containing 17α- ethinylestradiol (1:4, sediment solution) in the concentrations of 50; 100; 200; 400; 800 and 1600 μg.L-1, and photoperiod of 12h light/12h dark and with a temperature of 22 to 26ºC. The acute tests were performed using III larvae instar without aeration and the chronic tests were performed using I instar larvae with aeration. The organisms were fed with 5 ml of a solution containing 1 liter of deionized water and 5.0 g of crushed fish feed (TetraMin®). The test performed was static, were the solution was not changed from the beginning to the end of the test of each F1, F2 and F3 generation. In acute tests (96h) the results showed that the compound under study shows no toxicity. In chronic tests only the third generation showed a low survival (43.3 to 56.6%) indicating toxicity to the test organism, which was confirmed by the one-way ANOVA test with p ≤ 0.05. The adult emergency of the organism in the third generation was of 22 days, with a delay of five days in comparison to the other treatments, indicating that the compound tested influences development. In the analysis of potential fecundity, the statistical tests indicated that there was a significant difference between the treatments and the control only in the third generation, which can be inferred that the tested compound interferes in the potential fecundity of Chironomus sancticaroli. No oral deformities were found in the larvae in the three generations analyzed. In order to do so, further studies are required, aiming at a larger number of organisms (n ≥ 100) in a larger number of generations, so that the results are more conclusive with respect to the interference of the tested compound on the biology of Chironomus sancticaroli.

Fish are particularly vulnerable to the exposure of anthropogenic pollutants, with a vast array of endocrine disrupting chemicals (EDCs) introduced into the aquatic environment via sewage discharge, waste disposal and land runoff. Brominated flame retardants (BFRs) are halogenated flame retardants that are used to effectively inhibit the flammability of various materials including plastic products, electrical appliances, construction materials and textiles. BFRs are ubiquitous environmental contaminants and are known to disrupt thyroid hormone (TH) homeostasis in several vertebrate species, including fish. Given the vital role of THs in a wide range of developmental processes and physiological functions, assessing and identifying thyroid disrupting chemicals is crucial for safe guarding the long-term health of humans and wildlife. In fish the molecular mechanisms underlying TH disruption by BFRs and the effects on TH-sensitive tissues during early life stages remains unclear. This has been limited by the lack of fundamental knowledge on the TH system of fish and the difficulties associated with examining transcriptional changes in discrete embryonic-larval tissues. Here I have established the expression profiles of a suite of genes in the hypothalamic-pituitary-thyroid (HPT) axis of zebrafish (Danio rerio) during embryonic-larval stages and their regulation by the biologically active TH (3, 5, 3′- tri-iodothyronine; T3). Using molecular tools (whole mount is situ hybridisation and RT-PCR), I demonstrate that a number of genes display spatial and temporal expression profiles during embryo/larval development, and their regulation by T3 was tissue- and developmental stage-specific. I subsequently demonstrated that TBBPA and BDE-47, two important BFR compounds, disrupted TH homeostasis at multiple levels of the HPT axis of zebrafish embryo-larvae after short sub-acute exposures. These compounds altered the expression of genes associated with TH conjugation and clearance, thyroid follicle development and TH transport. In addition, we suggest that TH target genes in the brain, liver, pronephric ducts and craniofacial tissues of zebrafish embryo-larvae may be particularly vulnerable to TBBPA and BDE-47 exposure. It has been proposed that environmental pollutants can disrupt TH signalling in wildlife by disrupting the activity of thyroid receptors (TRs), ligand-binding transcription factors, which mediate the genomic actions of THs. The ability of BFRs to disrupt fish TRs has not yet been examined. Here I developed an in vitro reporter gene transcriptional assay for zebrafish thyroid hormone receptors (zfTRα and zfTRβ) in human embryonic kidney cells and investigated their interactions with several BFR compounds. The assays were optimised and validated using the natural TR agonist T3 in cells transiently transfected with two reporter vector constructs, pGL4.24-PAL and pGL4.24-DR4. None of the six brominated flame retardants tested, namely, tetrabromobisphenol A (TBBPA), hexabromocyclododecane (HBCD), 2,2′,4,4′-tetra-bromodiphenyl ether (BDE-47), 2,2′,4,4′,6-penta-bromodiphenyl ether (BDE-100), 2,2′,3,4,4′,5′,6-hepta-bromodiphenyl ether (BDE-183) and deca-bromodiphenyl ether (BDE-209) had an agonistic effect on zfTRα and zfTRβ activity. These results are consistent with our previous finding which suggests that altered TH homeostasis may be a result of increased metabolism and excretion of THs and/or changes in the production of TH by the thyroid follicles. In conclusion, this investigative work aids the understanding of fundamental TH processes in fish, such as gene expression and regulation, and increases our understanding of the mechanisms and potential targets of BFRs in fish.

A água constitui um dos compostos de maior distribuição e importância na crosta terrestre. Sua importância para vida está no fato de que nenhum processo metabólico ocorre sem a sua ação direta ou indireta. Entre os vários compostos contaminantes dos ambientes aquáticos, os hormônios, estrógenos naturais e sintéticos, devem ser vistos com uma maior importância, devido a sua persistência no ambiente. O 17α-etinilestradiol (EE2) é um hormônio sintético utilizado na formulação de contraceptivos orais, transdérmico e injetáveis. O presente estudo tem como objetivo analisar o efeito do hormônio sintético 17α-etinilestradiol sobre a biologia do invertebrado aquático Chironomus sancticaroli analisando três gerações do ciclo de vida da espécie. Nos experimentos foram utilizados areia fina comum (lavada em água corrente, seca em estufa a 60ºC e levada a mufla por 4 horas a 560ºC) e água deionizada (condutividade entre 25-55 μS.cm-1, dureza entre 12 e 16 mg.L-1 para CaCO3, pH entre 6,5 a 7,5). Foram realizadas 4 réplicas utilizando-se potes de 2 litros para cada concentração do hormônio e para o controle. Para os testes, foram colocadas 15 larvas, contendo 60 g de areia de cultivo e 240 ml de solução contendo 17α-etinilestradiol (na proporção 1:4, sedimento-solução) nas concentrações de 50; 100; 200; 400; 800 e 1600 μg.L-1, e fotoperíodo de 12h luz/ 12 h escuro e com temperatura de 22 a 26ºC. Os testes agudos foram realizados utilizando-se larvas de IV ínstar sem aeração e os testes crônicos foram realizados utilizando-se larvas de I ínstar com aeração. Os organismos foram alimentados com 5 ml de uma solução contendo 1 litro de água deionizada e 5,0 g de ração para peixe triturada (TetraMin®). O teste realizado foi estático, ou seja, a solução não era trocada do início ao fim do teste de cada geração F1, F2 e F3. Em testes agudos (96h) os resultados mostraram que o composto em estudo não apresenta toxicidade. Nos testes crônicos apenas a terceira geração mostrou uma baixa sobrevivência (43,3 a 56,6%) indicando toxicidade do composto ao organismo-teste, o que foi confirmado pelo teste ANOVA one-way com p ≤ 0,05. O tempo de emergência do organismo na terceira geração foi de 22 dias, havendo um atraso de cinco dias em comparação aos demais tratamentos, indicando que o composto testado pode influenciar no tempo de desenvolvimento do organismo-teste. Na análise da fecundidade potencial, os testes estatísticos indicaram haver uma diferença significativa entre os tratamentos e o controle somente na terceira geração, o que se pode inferir que o composto testado interfere na fecundidade potencial do Chironomus sancticaroli. Não foram encontradas deformidades bucais nas larvas nas três gerações analisadas. Para tanto, faz-se necessários estudos posteriores, visando um número maior de organismos (n ≥ 100) em um número maior de gerações, para que os resultados sejam mais conclusivos no que diz respeito a interferência do composto testado sobre a biologia do Chironomus sancticaroli. / Water is one of the compounds of great distribution and importance in the Earth\'s. Its importance to life lies in the fact that no metabolic process occurs without its direct or indirect action. Among the various contaminating compounds in aquatic environments, hormones, natural and synthetic estrogens, should be viewed with great importance because of their persistence in the environment. 17α-ethinylestradiol (EE2) is a synthetic hormone used in the formulation of oral, transdermal, and injectable contraceptives. The present study aims to analyze the effect of the synthetic hormone 17α-ethinylestradiol on the biology of the aquatic invertebrate Chironomus sancticaroli analyzing three generations of life cycle. In the experiments, common fine sand was used (washed with deionized water, oven dried at 60ºC and muffled for 4 hours at 560ºC) and deionized water (conductivity between 25-55 μS.cm-1, hardness between 12 and 16 mg.L-1 for CaCO3, and pH between 6.5 to 7.5). Four replicates were performed using 2-liter pots for each concentration of the hormone and for the control. For the tests, 15 larvae, containing 60 g of sand and 240 ml of solution containing 17α- ethinylestradiol (1:4, sediment solution) in the concentrations of 50; 100; 200; 400; 800 and 1600 μg.L-1, and photoperiod of 12h light/12h dark and with a temperature of 22 to 26ºC. The acute tests were performed using III larvae instar without aeration and the chronic tests were performed using I instar larvae with aeration. The organisms were fed with 5 ml of a solution containing 1 liter of deionized water and 5.0 g of crushed fish feed (TetraMin®). The test performed was static, were the solution was not changed from the beginning to the end of the test of each F1, F2 and F3 generation. In acute tests (96h) the results showed that the compound under study shows no toxicity. In chronic tests only the third generation showed a low survival (43.3 to 56.6%) indicating toxicity to the test organism, which was confirmed by the one-way ANOVA test with p ≤ 0.05. The adult emergency of the organism in the third generation was of 22 days, with a delay of five days in comparison to the other treatments, indicating that the compound tested influences development. In the analysis of potential fecundity, the statistical tests indicated that there was a significant difference between the treatments and the control only in the third generation, which can be inferred that the tested compound interferes in the potential fecundity of Chironomus sancticaroli. No oral deformities were found in the larvae in the three generations analyzed. In order to do so, further studies are required, aiming at a larger number of organisms (n ≥ 100) in a larger number of generations, so that the results are more conclusive with respect to the interference of the tested compound on the biology of Chironomus sancticaroli.

Made available in DSpace on 2017-07-10T14:38:26Z (GMT). No. of bitstreams: 1 louise.pdf: 1784422 bytes, checksum: 60f4897ec789c94dd1c7ec0eda64a208 (MD5) Previous issue date: 2015-02-12 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / 1. The size spectrum associates the abundance of individuals with the size of their body. The main objective was to investigate the influence of reservoir operation regime on the process of energy transfer in fishes assemblage, testing the hypothesis that the reservoir operation modify the spatial variability of the slopes of the size spectra. 2. For this, samples were carried out the period from January 2005 to December 2007. Data were obtained in eight reservoir with different operation regime, located in the state of Paraná, southern Brazil. To calculate the slopes of fish size spectra we used Pareto I model. The effects of operation regime on the size spectra were evaluate from the paired t test. 3. The results showed that the reservoir operation regime presents significant effect on the size spectra of the fish assemblages, wherein the slopes of spectra indicated that the reservoirs tend to present higher proportions of the small individuals. This effect were more pronounced in the reservoirs that operate in accumulation, indicating less efficient energy transfer through food webs in these environments / O espectro de tamanho associa a abundância de indivíduos com o tamanho do corpo destes. O objetivo principal foi investigar o efeito do regime de operação de reservatórios, sobre o processo de transferência de energia em assembleias ictiícas, testando-se a hipótese de que o regime de operação do reservatório altera a variabilidade espacial das inclinações dos espectros de tamanho, influenciando o fluxo de energia nos distintos reservatórios. Para isso, as amostras foram coletadas no período de janeiro de 2005 a dezembro de 2007. Os dados foram obtidos de oito reservatórios, com diferentes regimes de operação localizados no estado do Paraná, região sul do Brasil. Para calcular as inclinações dos espectros de tamanho de peixes foi utilizado um modelo de Pareto tipo I. Os efeitos dos regimes de operação sobre os espectros de tamanho foram avaliados através do Teste t pareado. Com a análise dos resultados evidenciou-se que o regime de operação do reservatório apresenta efeito significativo sobre os espectros de tamanho das assembleias de peixes, sendo que as inclinações dos espectros indicaram que os reservatórios tendem a apresentar maiores proporções de indivíduos pequenos, sendo esse efeito mais pronunciado nos reservatórios que operam em regime de acumulação, indicando menor eficiência na transferência de energia nesses ambientes