SILVA, Camila Magalhães. Detecção de Aeromonas spp. em amostras de água superficial e sedimento ao longo de um gradiente de salinidade no estuário do Rio Cocó - Ceará. 2009. 86 f. : Dissertação (mestrado) - Universidade Federal do Ceará, Centro de Ciências Agrárias, Departamento de Engenharia de Pesca, Fortaleza-CE, 2009 / Submitted by Nádja Goes (nmoraissoares@gmail.com) on 2016-07-11T15:14:11Z No. of bitstreams: 1 2009_dis_cmsilva.pdf: 1804188 bytes, checksum: cd5c4f372d190f7b3e2f64821e983185 (MD5) / Approved for entry into archive by Nádja Goes (nmoraissoares@gmail.com) on 2016-07-11T15:14:50Z (GMT) No. of bitstreams: 1 2009_dis_cmsilva.pdf: 1804188 bytes, checksum: cd5c4f372d190f7b3e2f64821e983185 (MD5) / Made available in DSpace on 2016-07-11T15:14:50Z (GMT). No. of bitstreams: 1 2009_dis_cmsilva.pdf: 1804188 bytes, checksum: cd5c4f372d190f7b3e2f64821e983185 (MD5) Previous issue date: 2009 / This research work was designed to detect the presence of Aeromonas in the Cocó River estuary, Fortaleza, Ceará State, Brazil. The database consisted of 30 samples of the river’s surface water and 30 samples of the river’s sooil, in the period from September, 2007 to April, 2008.. They were amenable, simultaneously, to counting of bacteria on Agar Gelatin Phosphate Salt (GSP) plus 20μg/mL of ampicilim (UFC/mL or UFC/g) The results showed dissemination of Aeromonas in the estuary. The counts for the water samples varied from 10 to 7,050 and from 25 to 38,500 UFC/mL at points A and B respectively; and from 100 to 37,500 UFC/g, and 1,200 to 43500 UFC/g at points A and B respectively. At point C, the counts for water and sediment were smaller than 10 UFC per ml or gram in all samples The occurrence of the greatest indices of Aeromonas in April, at the height of the rainy season, and the lowest in Septemer, at the height of the dry season, suggests there to be a probable seasonality of bacteria density in the studied environment. Among the 41 isolated strains were found the species A. caviae, A. sobria, A. trota, A. salmonicida and A. allossacharophyla. All the strains of Aeromonas sp. were found to be sensitive to cloranfenicol and ceftriaxona except for ampicillim, to which they showed 100% resistance.All the stirps showed resistance to two out of the nine tested antibiotics. After the Curing’ technique, the eritromicina resistance seems to be of plasmidian origin. / Este projeto teve como objetivo principal a pesquisa de Aeromonas spp. em água de superfície e sedimento em três pontos distintos ao longo do rio Cocó, Ceará. Foram realizadas coletas no período de outubro de 2007 a abril de 2008 gerando um total de 30 amostras de água e 30 de sedimento. A quantificação da comunidade bacteriana pertencente ao gênero Aeromonas foi feita através de plaqueamento direto sobre Agar Gelatina Fosfato Sal (Agar GSP acrescido de 20μg/mL de ampicilina). Nas amostras de água, os valores obtidos variaram de 10 a 7.050 UFC/mL e de 25 a 38.500 UFC/mL nos pontos A e B, respectivamente. Nas amostras de sedimento, as contagens variaram de 100 a 37500 UFC/g e 1.200 a 43.500 UFC/g nos pontos A e B, respectivamente. Nas amostras de água e sedimento do ponto C, os valores foram menores que 10 UFC (por mL ou g) em todas as coletas. As maiores contagens foram verificadas no mês de abril, período de chuva, e as menores no mês de setembro, período de estiagem. Foram feitos isolamentos e após identificação as estirpes foram submetidas à teste de antibiograma e à técnica da “cura” do plasmídio. Dentre as 41 cepas isoladas, foram identificadas as espécies A. caviae, A. sobria, A. trota, A. salmonicida e A. allossacharophyla. Todas as cepas se mostraram sensíveis ao cloranfenicol e ceftriaxona. Todas as estirpes apresentaram resistência a, pelo menos, dois dos nove antibióticos testados. Após a técnica de cura, a maior parte da resistência a eritromicina ficou caracterizada como de origem plasmidial.Conclui-se que o estuário do Rio Cocó está contaminado por Aeromonas e que muitas delas apresentam resistências a antibióticos denotando um ambiente poluído e de risco para a população que usa suas águas para lazer, pesca ou outra atividade qualquer.

The object of this thesis is the assessment of fish contamination by selected foreign substances as toxic metals, polychlorinated biphenyls and pesticides in 31 selected fishing grounds. The monitoring was realized between years 2006 and 2010. Fish were caught by electric device and fishing rods. Concentrations of Hg, Cd, Pb, PCB, DDT, HCH and HCB in fish muscle tissues were monitored. Common bream (Abramis brama) was selected as a reference species for a comparison of the monitored sites. The results of analysis were compared with valid hygienic limits. Overrun of hygienic limit for some of the monitored pollutants were observed in 18 localities. We found mercury as a major pollutant in the aquatic environment.

Embora a prática de atividade física tenha se tornado comum em ambiente aquático, ainda há pouca informação a respeito das características biomecânicas da caminhada de idosos nesse ambiente. No intuito de investigar essas características, o objetivo do presente estudo foi comparar parâmetros cinemáticos (lineares e angulares) e eletromiográficos de idosas caminhando em ambiente terrestre (TE) e em ambiente aquático em piscina rasa (PR) e em piscina funda (PF). Doze mulheres idosas saudáveis foram avaliadas enquanto caminhavam em uma intensidade de esforço auto-selecionada (confortável) na terra e na água em PR e PF (imersas ao nível do processo xifóide). Variáveis cinemáticas e eletromiográficas foram registradas. Comparada às outras duas modalidades, em PF as idosas apresentaram menor velocidade, menor comprimento de passada e duração do período de apoio durante a caminhada. Ainda, os indivíduos caminharam com o tronco mais inclinado a frente e com maior amplitude de movimento (ADM) do quadril e do joelho. Essas alterações cinemáticas foram associadas a maior atividade dos músculos eretor da coluna (EC), bíceps femoral (BF) e reto femoral (RF). Por outro lado, a atividade do músculo gastrocnêmio (GAS) foi inferior a encontrada em TE. Já em PR, as idosas caminharam com menor velocidade, menor comprimento de passada e duração do período de apoio comparado a caminhada em TE. A ADM do joelho também foi menor em PR. Ainda, a atividade do músculo BF foi superior durante o período de apoio, bem como do músculo RF durante o período de balanço. Em contrapartida, a atividade do músculo GAS foi inferior durante o período de apoio. Em uma mesma intensidade de esforço auto-selecionada (confortável) os indivíduos caminharam mais lentamente em ambiente aquático. Nessa condição, a necessidade de superar a grande resistência oferecida ao movimento e à ausência de contato do pé com o solo caracterizaram a caminhada em PF como um exercício de grande ADM do quadril e do joelho, grande exigência dos músculos EC, BF e RF e pequena exigência do GAS. Por sua vez, a necessidade de superar a grande resistência oferecida ao movimento associado ao reduzido peso hidrostático caracterizaram a caminhada em PR como um exercício de pequena ADM do joelho, grande exigência dos músculos BF e RF e pequena exigência do GAS em idosos. Esses resultados contribuirão para um melhor entendimento acerca das características apresentadas por idosos caminhando em PF e PR sendo de grande auxilio na elaboração de programas de treinamento e reabilitação para essa população. / Although water environment has been employed for different physical activities, there is little information about biomechanical characteristics of elderly walking at shallow and deep water. With the purpose to investigate these characteristics, the mean of the present study was to compare kinematics (linear end angular) and electromyographic patterns of elderly individuals walking on land (LW), in shallow (SWW) and deep water (DWW). Twelve healthy elderly women were analyzed while walking at self-selected pace (moderate) on land and in water (at the xiphoid process level). Kinematic and electromyographic variables were registered. Compared to LW and SWW, during DWW elderly women presented the slowest speed, the shortest stride length and support phase duration. Individuals walked with trunk at the most forward inclined position, as well with the largest hip and knee joints range of motion (ROM). This kinematic changes were related to the highest erector spinae (ES), biceps femoris (BF) and rectus femoris (RF) muscles activity. On other hand, gastrocnemius medialis (GM) activity was lower than during TE situation. During SWW, elderly women walked at slower speed, shorter stride length and support phase period when compared to LW. The knee ROM was also lower. However, BF muscle activity was higher during stance period as well as RF activity during swing phase. In opposition, GAS muscle activity was lower during stance phase. At the same self-selected pace (moderate) elderly women walked slower in aquatic environment. In this condition, the necessity to move against the drag force without feet contact from the bottom of the swimming pool described the DWW walking as an exercise performed with large hip and knee ROM, high stimulation of ES, BF and RF muscles and low stimulation of GM muscle. In other way, the necessity to move against the drag force associated to the apparent body weight reduction described the SWW as an exercise performed with short knee ROM, high stimulation of BF and RF muscles and low stimulation of GM muscle in elderly women. The present results will contribute to a better understanding about elderly walking characteristics in shallow and deep water, being useful for training and rehabilitation programs designed by these population.

A contribuição deste trabalho é apresentar uma metodologia de avaliação de risco ecológico do ambiente aquático utilizando-se dados provenientes de programas de monitoramento ambiental. O estudo tem como cenário um trecho do Rio Jacuí, município de São Jerônimo – RS, Brasil, que foi avaliado através da aplicação de um programa de monitoramento ambiental. Consideraram-se como variável explicativa deste estudo, as evidências registradas nos compartimentos abióticos, água superficial e sedimento. As evidências químicas foram decorrentes da presença dos metais Hg, Pb e Zn e as evidências ecotoxicológicas de ensaios de toxicidade aquática com Ceriodaphinia dubia para água superficial e Hyalella azteca para sedimento. Consideraram-se como variáveis respostas as evidências biológicas compostas pelos dados de riqueza, índice de Shannon-Weaver, equitatividade e densidade numérica das espécies das comunidades zooplantônica e bentônica. O risco ecológico (Baixo, Médio e Alto) foi caracterizado pela associação à qualidade ambiental (Ótima, Alerta e Crítica), respectivamente, estabelecida pelas evidências registradas. Os resultados permitem considerar que é possível o uso de programas de monitoramento ambiental para avaliação de risco ecológico, se contiverem, além dos dados químicos e ecotoxicológicos exigidos pela legislação ambiental, dados do monitoramento da biota residente. / The contribution of this work is to present a methodology for ecological risk assessment in an aquatic environment using data derived from environmental monitoring programs. The location focused by this study was a segment of the Jacuí River, in the town of São Jerônimo – RS, Brazil, which was assessed by applying an environmental monitoring program. The evidence recorded from the abiotic compartments surface water and sediments was considered an explanatory variable. The chemical evidence stemmed from the presence of Hg, Pb and Zn, while the ecotoxicological evidence resulted from aquatic toxicity tests using Ceriodaphinia dubia for surface water and Hyalella azteca for sediments. The biological evidence from the Shannon-Weaver index, species richness, equitability and numerical density data in zooplanktonic and benthonic communities was considered the response variable. The ecological risk (Low, Medium, and High) was characterized by the association with environmental quality (Great, Warning, and Critical), established by the evidence recorded. The results have shown that it is possible to use environmental monitoring programs to evaluate of ecological risk assessment, if they have chemical and ecotoxicological data required by environmental laws, and monitoring data of resident biota.

This research work was designed to detect the presence of Aeromonas in the Cocà River estuary, Fortaleza, Cearà State, Brazil. The database consisted of 30 samples of the riverâs surface water and 30 samples of the riverâs sooil, in the period from September, 2007 to April, 2008.. They were amenable, simultaneously, to counting of bacteria on Agar Gelatin Phosphate Salt (GSP) plus 20μg/mL of ampicilim (UFC/mL or UFC/g) The results showed dissemination of Aeromonas in the estuary. The counts for the water samples varied from 10 to 7,050 and from 25 to 38,500 UFC/mL at points A and B respectively; and from 100 to 37,500 UFC/g, and 1,200 to 43500 UFC/g at points A and B respectively. At point C, the counts for water and sediment were smaller than 10 UFC per ml or gram in all samples The occurrence of the greatest indices of Aeromonas in April, at the height of the rainy season, and the lowest in Septemer, at the height of the dry season, suggests there to be a probable seasonality of bacteria density in the studied environment. Among the 41 isolated strains were found the species A. caviae, A. sobria, A. trota, A. salmonicida and A. allossacharophyla. All the strains of Aeromonas sp. were found to be sensitive to cloranfenicol and ceftriaxona except for ampicillim, to which they showed 100% resistance.All the stirps showed resistance to two out of the nine tested antibiotics. After the Curingâ technique, the eritromicina resistance seems to be of plasmidian origin. / Este projeto teve como objetivo principal a pesquisa de Aeromonas spp. em Ãgua de superfÃcie e sedimento em trÃs pontos distintos ao longo do rio CocÃ, CearÃ. Foram realizadas coletas no perÃodo de outubro de 2007 a abril de 2008 gerando um total de 30 amostras de Ãgua e 30 de sedimento. A quantificaÃÃo da comunidade bacteriana pertencente ao gÃnero Aeromonas foi feita atravÃs de plaqueamento direto sobre Agar Gelatina Fosfato Sal (Agar GSP acrescido de 20μg/mL de ampicilina). Nas amostras de Ãgua, os valores obtidos variaram de 10 a 7.050 UFC/mL e de 25 a 38.500 UFC/mL nos pontos A e B, respectivamente. Nas amostras de sedimento, as contagens variaram de 100 a 37500 UFC/g e 1.200 a 43.500 UFC/g nos pontos A e B, respectivamente. Nas amostras de Ãgua e sedimento do ponto C, os valores foram menores que 10 UFC (por mL ou g) em todas as coletas. As maiores contagens foram verificadas no mÃs de abril, perÃodo de chuva, e as menores no mÃs de setembro, perÃodo de estiagem. Foram feitos isolamentos e apÃs identificaÃÃo as estirpes foram submetidas à teste de antibiograma e à tÃcnica da âcuraâ do plasmÃdio. Dentre as 41 cepas isoladas, foram identificadas as espÃcies A. caviae, A. sobria, A. trota, A. salmonicida e A. allossacharophyla. Todas as cepas se mostraram sensÃveis ao cloranfenicol e ceftriaxona. Todas as estirpes apresentaram resistÃncia a, pelo menos, dois dos nove antibiÃticos testados. ApÃs a tÃcnica de cura, a maior parte da resistÃncia a eritromicina ficou caracterizada como de origem plasmidial.Conclui-se que o estuÃrio do Rio Cocà està contaminado por Aeromonas e que muitas delas apresentam resistÃncias a antibiÃticos denotando um ambiente poluÃdo e de risco para a populaÃÃo que usa suas Ãguas para lazer, pesca ou outra atividade qualquer.

A contribuição deste trabalho é apresentar uma metodologia de avaliação de risco ecológico do ambiente aquático utilizando-se dados provenientes de programas de monitoramento ambiental. O estudo tem como cenário um trecho do Rio Jacuí, município de São Jerônimo – RS, Brasil, que foi avaliado através da aplicação de um programa de monitoramento ambiental. Consideraram-se como variável explicativa deste estudo, as evidências registradas nos compartimentos abióticos, água superficial e sedimento. As evidências químicas foram decorrentes da presença dos metais Hg, Pb e Zn e as evidências ecotoxicológicas de ensaios de toxicidade aquática com Ceriodaphinia dubia para água superficial e Hyalella azteca para sedimento. Consideraram-se como variáveis respostas as evidências biológicas compostas pelos dados de riqueza, índice de Shannon-Weaver, equitatividade e densidade numérica das espécies das comunidades zooplantônica e bentônica. O risco ecológico (Baixo, Médio e Alto) foi caracterizado pela associação à qualidade ambiental (Ótima, Alerta e Crítica), respectivamente, estabelecida pelas evidências registradas. Os resultados permitem considerar que é possível o uso de programas de monitoramento ambiental para avaliação de risco ecológico, se contiverem, além dos dados químicos e ecotoxicológicos exigidos pela legislação ambiental, dados do monitoramento da biota residente. / The contribution of this work is to present a methodology for ecological risk assessment in an aquatic environment using data derived from environmental monitoring programs. The location focused by this study was a segment of the Jacuí River, in the town of São Jerônimo – RS, Brazil, which was assessed by applying an environmental monitoring program. The evidence recorded from the abiotic compartments surface water and sediments was considered an explanatory variable. The chemical evidence stemmed from the presence of Hg, Pb and Zn, while the ecotoxicological evidence resulted from aquatic toxicity tests using Ceriodaphinia dubia for surface water and Hyalella azteca for sediments. The biological evidence from the Shannon-Weaver index, species richness, equitability and numerical density data in zooplanktonic and benthonic communities was considered the response variable. The ecological risk (Low, Medium, and High) was characterized by the association with environmental quality (Great, Warning, and Critical), established by the evidence recorded. The results have shown that it is possible to use environmental monitoring programs to evaluate of ecological risk assessment, if they have chemical and ecotoxicological data required by environmental laws, and monitoring data of resident biota.

Embora a prática de atividade física tenha se tornado comum em ambiente aquático, ainda há pouca informação a respeito das características biomecânicas da caminhada de idosos nesse ambiente. No intuito de investigar essas características, o objetivo do presente estudo foi comparar parâmetros cinemáticos (lineares e angulares) e eletromiográficos de idosas caminhando em ambiente terrestre (TE) e em ambiente aquático em piscina rasa (PR) e em piscina funda (PF). Doze mulheres idosas saudáveis foram avaliadas enquanto caminhavam em uma intensidade de esforço auto-selecionada (confortável) na terra e na água em PR e PF (imersas ao nível do processo xifóide). Variáveis cinemáticas e eletromiográficas foram registradas. Comparada às outras duas modalidades, em PF as idosas apresentaram menor velocidade, menor comprimento de passada e duração do período de apoio durante a caminhada. Ainda, os indivíduos caminharam com o tronco mais inclinado a frente e com maior amplitude de movimento (ADM) do quadril e do joelho. Essas alterações cinemáticas foram associadas a maior atividade dos músculos eretor da coluna (EC), bíceps femoral (BF) e reto femoral (RF). Por outro lado, a atividade do músculo gastrocnêmio (GAS) foi inferior a encontrada em TE. Já em PR, as idosas caminharam com menor velocidade, menor comprimento de passada e duração do período de apoio comparado a caminhada em TE. A ADM do joelho também foi menor em PR. Ainda, a atividade do músculo BF foi superior durante o período de apoio, bem como do músculo RF durante o período de balanço. Em contrapartida, a atividade do músculo GAS foi inferior durante o período de apoio. Em uma mesma intensidade de esforço auto-selecionada (confortável) os indivíduos caminharam mais lentamente em ambiente aquático. Nessa condição, a necessidade de superar a grande resistência oferecida ao movimento e à ausência de contato do pé com o solo caracterizaram a caminhada em PF como um exercício de grande ADM do quadril e do joelho, grande exigência dos músculos EC, BF e RF e pequena exigência do GAS. Por sua vez, a necessidade de superar a grande resistência oferecida ao movimento associado ao reduzido peso hidrostático caracterizaram a caminhada em PR como um exercício de pequena ADM do joelho, grande exigência dos músculos BF e RF e pequena exigência do GAS em idosos. Esses resultados contribuirão para um melhor entendimento acerca das características apresentadas por idosos caminhando em PF e PR sendo de grande auxilio na elaboração de programas de treinamento e reabilitação para essa população. / Although water environment has been employed for different physical activities, there is little information about biomechanical characteristics of elderly walking at shallow and deep water. With the purpose to investigate these characteristics, the mean of the present study was to compare kinematics (linear end angular) and electromyographic patterns of elderly individuals walking on land (LW), in shallow (SWW) and deep water (DWW). Twelve healthy elderly women were analyzed while walking at self-selected pace (moderate) on land and in water (at the xiphoid process level). Kinematic and electromyographic variables were registered. Compared to LW and SWW, during DWW elderly women presented the slowest speed, the shortest stride length and support phase duration. Individuals walked with trunk at the most forward inclined position, as well with the largest hip and knee joints range of motion (ROM). This kinematic changes were related to the highest erector spinae (ES), biceps femoris (BF) and rectus femoris (RF) muscles activity. On other hand, gastrocnemius medialis (GM) activity was lower than during TE situation. During SWW, elderly women walked at slower speed, shorter stride length and support phase period when compared to LW. The knee ROM was also lower. However, BF muscle activity was higher during stance period as well as RF activity during swing phase. In opposition, GAS muscle activity was lower during stance phase. At the same self-selected pace (moderate) elderly women walked slower in aquatic environment. In this condition, the necessity to move against the drag force without feet contact from the bottom of the swimming pool described the DWW walking as an exercise performed with large hip and knee ROM, high stimulation of ES, BF and RF muscles and low stimulation of GM muscle. In other way, the necessity to move against the drag force associated to the apparent body weight reduction described the SWW as an exercise performed with short knee ROM, high stimulation of BF and RF muscles and low stimulation of GM muscle in elderly women. The present results will contribute to a better understanding about elderly walking characteristics in shallow and deep water, being useful for training and rehabilitation programs designed by these population.

During the summer of 2013 the environmental office at Lycksele Municipality received a complaint, regarding algal blooms at the stream outlet between the lakes Kalven and Byssträsket in the southern parts of Lycksele Municipality. No deeper studies were made to ensure what could have caused the bloom. The purpose of this report was to examine if there was a specific source contributing to high levels of nutrients in the stream, mainly focusing on clear-cuts and a small dam by the stream inlet, and if the nutrient status differed along the stream flow. Therefore, suitable sites were picked for examination, following the stream flow between the two lakes, and in a stream not affected by clear-cuts for reference. Water samples were picked at each site, determining the status of the parameters total-nitrogen, total-phosphorus, nitrate, ammonium, pH and conductivity. The result showed quite high levels of total-phosphorus (ranging from 40-50 µg/l) and total-nitrogen (ranging from 350-450 µg/l), but low levels of ammonium and nitrate. The results showed no sign of a nutrient input from a specific location. The conclusion of this study is that the present nutrient levels could be high enough to result in a bloom, though probably dependent on contributing factors, such as warmer weather and lower water levels. An alternative explanation is that the nutrient levels could have been higher 2013, deriving from new clear-cuts, but that these clear-cuts stopped leaching nutrients due to older age. Hence, due to lack of previous studies no exact assumption can be made

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