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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Sublethal effects of pesticides in pipostrelle bats (Pipistrellus pipistrellus)

Swanepoel, Robert Eric January 1995 (has links)
No description available.
2

Sample preparation in environmental organic analysis

Barnabas, Ian Joseph January 1996 (has links)
No description available.
3

Investigations of molecular fluorescence based measurement of DDT residues

Sheikh, Sohail Hamid January 1998 (has links)
No description available.
4

Sources and Fate of Organochlorine Pesticides in North America and the Arctic

Jantunen, Liisa M. 21 April 2010 (has links)
Atmospheric transport and air-water exchange of organochlorine pesticides (OCPs) were investigated in temperate North America and the Arctic. OCPs studied were hexachlorocyclohexanes (HCHs, a-, b- and g-isomers), components of technical chlordane (trans- and cis-chlordane, trans-nonachlor), dieldrin, heptachlor exo-epoxide and toxaphene. Air and water samples were taken on cruises in the Great Lakes and Arctic to determine concentrations and gas exchange flux direction and magnitude. The Henry’s law constant, which describes the equilibrium distribution of a chemical between air and water, was determined for several OCPs as a function of temperature and used to assess the net direction of air-water exchange. Air samples were collected in Alabama to investigate southern U.S. sources of OCPs. Chemical markers (isomers, and enantiomers of chiral OCPs) were employed to infer sources and trace gas exchange. Elevated air concentrations of toxaphene and chlordanes were found in Alabama relative to the Great Lakes, indicating a southern U.S. source. Profiles of toxaphene compounds in air were similar to those in soil by being depleted in easily degraded species, suggesting that soil emissions control air concentrations. Gas exchange fluxes in the Great Lakes indicated near-equilibrium between air and water with excursions to net volatilization or deposition. Net volatilization of a-HCH from the Arctic Ocean was traced by evasion of non-racemic a-HCH into the atmosphere.
5

Sources and Fate of Organochlorine Pesticides in North America and the Arctic

Jantunen, Liisa M. 21 April 2010 (has links)
Atmospheric transport and air-water exchange of organochlorine pesticides (OCPs) were investigated in temperate North America and the Arctic. OCPs studied were hexachlorocyclohexanes (HCHs, a-, b- and g-isomers), components of technical chlordane (trans- and cis-chlordane, trans-nonachlor), dieldrin, heptachlor exo-epoxide and toxaphene. Air and water samples were taken on cruises in the Great Lakes and Arctic to determine concentrations and gas exchange flux direction and magnitude. The Henry’s law constant, which describes the equilibrium distribution of a chemical between air and water, was determined for several OCPs as a function of temperature and used to assess the net direction of air-water exchange. Air samples were collected in Alabama to investigate southern U.S. sources of OCPs. Chemical markers (isomers, and enantiomers of chiral OCPs) were employed to infer sources and trace gas exchange. Elevated air concentrations of toxaphene and chlordanes were found in Alabama relative to the Great Lakes, indicating a southern U.S. source. Profiles of toxaphene compounds in air were similar to those in soil by being depleted in easily degraded species, suggesting that soil emissions control air concentrations. Gas exchange fluxes in the Great Lakes indicated near-equilibrium between air and water with excursions to net volatilization or deposition. Net volatilization of a-HCH from the Arctic Ocean was traced by evasion of non-racemic a-HCH into the atmosphere.
6

Heavy Metal, Organochlorine Pesticide and Polychlorinated Biphenyl Contamination in Arctic Ground Squirrels (Spermophilus Parryi) in Northern Alaska

Allen-Gil, S. M., Landers, D. H., Wade, T. L., Sericano, J. L., Lasorsa, B. K., Crecelius, E. A., Curtis, L. R. 01 December 1997 (has links)
Heavy metal and organochlorine (OC) concentrations, including organochlorine pesticides and polychlorinated biphenyl congeners (PCBs), were determined in arctic ground squirrels (Spermophilus parryi) from three sites in the Brooks Range of northern Alaska in 1991-93. Heavy metals were present in most squirrel livers collected, with concentrations of trace elements (As, Cd, Hg, Ni, and Pb) averaging below 1 μg/g wet weight. Hexachlorobenzene (HCB), p,p'-DDE, gamma hexachlorocyclohexane (γ-HCH), trans-nonachlor, and PCBs 138, 153, and 170 were the most frequently detected OCs in fat and liver. Average concentrations of individual OC analytes were below 20 ng/g wet weight in liver and below 15 ng/g wet weight in fat. Rank correlations indicate that concentrations of heavy metals and of OCs accumulate in concert with one another (As, Cd, Cu, and Zn; PCBs 138, 170, and 180). Although heavy metal and OC concentrations are low relative to other areas and other arctic species, the occurrence of these compounds illustrates the global pervasiveness of persistent organic compounds and the potential for bioaccumulation in the terrestrial arctic food web.
7

Determinação de pesticidas organoclorados em tecidos de tartarugas-verdes (Chelonia mydas) provenientes da costa sudeste do Brasil: estudo da ocorrência em animais com e sem fibropapilomatose / Determination of organochlorine pesticides in tissues of green turtles (Chelonia mydas) from the southeastern coast of Brazil: study of the occurrence in animals with and without fibropapillomatosis

Sarmiento, Angelica Maria Sanchez 27 September 2013 (has links)
O aumento das intervenções antropogênicas, nos âmbitos marinho e costeiro representa grande risco aos ecossistemas de suporte de numerosas populações de animais como as tartarugas marinhas. Desequilíbrios no balanço ecológico desses habitats afetam negativamente a sobrevivência de quelônios de longa vida, como a Chelonia mydas, seriamente ameaçada de extinção. As ameaças à espécie incluem captura incidental por pesca, doenças e degradação dos habitats de alimentação e nidificação. Uma das principais doenças é a fibropapilomatose (FP) ou Green Turtle Fibropapiloma Disease (GTFD), afecção tumoral e de caráter infeccioso que acomete predominantemente espécimes juvenis. Numerosas hipóteses têm surgido a respeito da etiologia da doença, mas ainda nada é conclusivo. Contudo existe o consenso de que a etiologia da mesma seja \"multifatorial\" envolvendo um α-herpesvírus como agente etiológico primário e a participação de diversos co-fatores genéticos, nutricionais e ambientais. No Brasil a prevalência média de FP en C. mydas varia conforme a região, existindo localidades nas quais não há registro da doença. O aumento da prevalência da FP tem sido implicada à degradação dos habitats marinhos, relacionado por sua vez a contaminantes ambientais como os organoclorados e seus metabólitos. Estes compostos caracterizam-se por serem altamente persistentes, bioacumulando e biomagnificando no ambiente marinho através do tempo. Além disso, são conhecidos por causarem inúmeros efeitos na saúde, interferindo na imunidade do indivíduo e favorecendo a manifestação de doenças, inclusive sendo apontados como agentes carcinogênicos. No presente trabalho foi desenvolvida uma técnica de extração e purificação baseada no método QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) para monitoramento pela cromatografia gasosa com captura de elétrons (GC-μECD) dos agrotóxicos clorados: α-BHC, β-BHC, Heptacloro, Dicofol, α-Endosulfan, β-endosulfan, Sulfato endosulfan, pp\' -DDD, op\' -DDD, pp\' -DDE, op\' -DDE e Mirex nos tecidos adiposo e hepático de 64 tartarugas-verdes juvenis (Cumprimento Curvo da Carapaça - CCC = 38,68±5,41cm) acometidas ou não pela FP (24 com FP vs. 40 sem FP), espécimes que vieram a óbito por captura incidental em redes de pesca ou foram encontradas encalhadas nas praias de Ubatuba/SP, Praia Grande/SP e Vitória/ES. Objetivou-se esclarecer possíveis correlações das suas concentrações com variáveis como sexo, tamanho (CCC), índice de condição corporal (ICC), severidade; índice de fibropapilomatose (FPI) e escore de fibropapilomatose (FPS) e ocorrência da doença em algumas localidades da região sudeste do país com diferentes taxas de prevalência da FP, na tentativa de inferir o papel dos mesmos na patogenia desta afecção. Foi observada correlação significativa entre a porcentagem lipídica entre as amostras dos tecidos adiposo e hepático, assim como entre a concentração total de organoclorados (ΣOCS) nos tecidos adiposo e hepático. Embora observadas algumas diferenças na presença ou ausência de alguns contaminantes, estas foram dispersas e não determinantes, ou seja, não permitiram estabelecer um padrão em relação aos diferentes fatores do histórico individual. Não foram encontradas diferenças significativas entre a ΣOCS para ambos os tecidos, em relação ao sexo do animal ou localidade, que permitissem inferir alguma relação entre o grau de contaminação e a variação regional da prevalência da FP. Também não foi possível identificar correlações significativas das concentrações dos poluentes em relação à presença da FP nem entre o FPI e o FPS e a ΣOCS nos tecidos adiposo e hepático. Tampouco foi possível identificar correlações significativas entre o ICC ou CCC e a ΣOCS. Os resultados deste trabalho apresentam um registro temporal do perfil de contaminação nas tartarugas-verdes de vida livre da costa sudeste, confirmando a biodisponibilidade de OCs nas diferentes regiões avaliadas. Embora não tenha sido encontrada uma correlação direta entre a concentração de OCs e a Fibropapilomatose, este estudo demonstra que as tartarugas verdes oriundas da costa sudeste do Brasil estão expostas a níveis significativos de pesticidas organoclorados os quais poderiam ter algum papel na etiologia multifatorial da doença. Estes contaminantes ambientais podem agir afetando a taxa de prevalência de FP, agindo possivelmente como agentes imunossupresores ou através da genotoxicidade e promoção tumoral. Estudos futuros serão desenvolvidos para melhor caracterizar a ação dessas substâncias e seus efeitos nas tartarugas marinhas e para esclarecer como outros fatores podem influenciar esses resultados. / The increase of anthropogenic impacts on both marine and coastal environments is threatening the ecosystems of numerous animal populations, including sea turtles. Disturbances in the ecological balance of these habitats negatively affect the survival of longlived chelonids such as green turtles (Chelonia mydas), which are already considered endangered. Threats to this species include incidental capture by fisheries, habitat degradation of nesting and feeding areas, and diseases. One of the most relevant diseases is fibropapillomatosis (FP) or Green Turtle Fibropapilloma Disease (GTFD), an infectious tumoral disease that predominantly affects juveniles. Numerous hypotheses have been proposed to explain this diseases aetiology, and while none has been conclusively demonstrated there is a consensus that it is multifactorial and involves a -herpesvirus as the primary etiologic agent along with genetic, nutritional and environmental cofactors. The prevalence of FP in C. mydas in Brazil varies among regions, with locations in which the disease remains unreported. Prevalence has been correlated to the degree of degradation of marine habitats, which in turn is related to the presence of environmental contaminants such as organochlorines and their metabolites. These compounds are difficult to break down and persist, bioaccumulate and biomagnify in marine environments over long periods of time. They are also known to produce numerous health effects in the organisms in which they accumulate, hampering immunity and favouring the manifestation of opportunistic disease, with some of these compounds being also carcinogens. In this study we developed extraction and purification technique based on the QuEChERS method (Quick, Easy, Cheap, Effective, Rugged and Safe) and used gas chromatography with electron capture (GC-μECD) to detect and quantify organochlorine (α-BHC, β-BHC, Heptachlor, Dicofol, α-endosulfan, β-endosulfan, Endosulfan sulphate, pp\' -DDD, op\' -DDD, pp\' -DDE, op\' -DDE, and Mirex) in adipose and hepatic tissue samples from 64 juvenile green sea turtles [Curved Carapace Length - CCL = 38.68 ± 5.41 cm] affected or not by FP (24 with FP vs. 40 without FP). These specimens died due to incidental capture by fishing nets or were found dead on beaches of Southeast Brazil: Ubatuba / SP, Praia Grande / SP and Vitória / ES. Aiming to clarify the role of the organochlorines in the pathogenesis of FP, we attempted to establish correlations between the concentration of these compounds and variables such as sex, size (CCL), Body Condition Index (BCI) and disease severity [fibropapillomatosis index (FPI) and fibropapillomatosis score (FPS)], and local FP prevalence. A significant correlation was observed between the lipid percentage of adipose and hepatic samples, as well as between adipose and hepatic organochlorine total concentrations (ΣOCS). Although some differences were observed regarding the presence or absence of contaminants in relation to characteristics of the individual history, it was not possible to establish patterns that reflected biological significance. For both adipose and hepatic tissues, no significant differences were found in the ΣOCS with regards to individual sex or capture locality that would allow inferring relationships between the individual contamination levels and the regional variation on the prevalence of FP. It was also not possible to identify significant relationships between each pollutant concentration in the adipose or hepatic tissue and the presence of FP. No correlation was observed between ΣOCS in adipose or hepatic tissues and FPI, FPS, BCI and CCL. The results provide a contamination profile of free-ranging green turtles of the southeast coast during the study period, confirming the bioavailability of OCs in the different locations evaluated. Although a direct correlation between the concentration of OCs and fibropapillomatosis was not found, this study demonstrates that green turtles from the southeast coast of Brazil are exposed to significant levels of organochlorine pesticides that could play a role in the multifactorial etiology of the disease. These contaminants may affect the prevalence of FP, possibly acting as immunosuppressive agents or through genotoxicity and tumor promotion. Future studies will be conducted to better characterize the role of these substances and their effects on sea turtles and to clarify how other factors that may influence their impacts.
8

Ocorrência de Pesticidas Organoclorados e Bifenilos Policlorados em tartarugas marinhas Chelonia mydas / Occurrence of organochlorine pesticides and polychlorinated biphenyls in sea turtles Chelonia mydas

Silva, Josilene da 25 June 2009 (has links)
Os compostos organoclorados (OCs), como pesticidas e bifenilos policlorados (PCBs), são persistentes, tóxicos e amplamente distribuídos através do transporte atmosférico e correntes oceânicas. Poucos são os estudos realizados de OCs em tartarugas, sendo que nenhum foi realizado na costa brasileira. A Chelonia mydas é a maior tartaruga marinha de carapaça dura, que se distribue por todos os oceanos, nas zonas de águas tropicais e subtropicais. O presente trabalho visa verificar a ocorrência de organoclorados na espécie C. mydas, bem como sua possível relação com algum tipo de alteração morfológica ou fisiológica. Foram coletadas amostras de gordura, fígado, rim e músculo em 27 espécimes juvenis do litoral de Ubatuba, São Paulo. Os organoclorados foram extraídos com solventes orgânicos e o extrato foi purificado com ácido concentrado. A identificação e quantificação dos PCBs e pesticidas foram realizadas em cromatógrafo a gás com espectrômetro de massas e com detector de captura de elétrons, respectivamente. Os pesticidas organoclorados não foram detectados em nenhuma amostra. As concentrações de PCBs totais em peso úmido foram de: <1,6 48,9 ng.g-1 em gordura, <1,6 17,4 ng.g-1 no fígado e <1,6 9,2 ng.g-1 no rim. Os baixos níveis encontrados estão relacionados principalmente a sua dieta alimentar, uma vez que a C. mydas é basicamente herbívora, e ao local de coleta, que é uma região não industrializada. / Organochlorine compounds, such as pesticides and polychlorinated biphenyls (PCBs), are persistent, toxics and widely distributed due to the atmospheric transport and oceanic currents. Few studies have reported the occurrence of these compounds in turtles, but none from the Brazilian Coast. Chelonia mydas is the biggest marine turtle with hard carapace that extends throughout tropical and subtropical seas around the world. The present study aims to assess the concentrations of organochlorines in the C. mydas as well as any relationship with morphological or physiological variations. Fat, liver and kidney samples were collected from 27 juvenile specimens found dead in Ubatuba Coast, São Paulo State. Organochlorine were extracted with organic solvents and the extracts were purified with concentrated acid. PCBs and pesticides were identified and quantified using a gas chromatograph with mass spectrometer and with electron capture detector, respectively. Pesticides were not detected in any sample analyzed. PCBs concentrations in wet weight were: <1.6 48.9 ng.g-1 in fat, <1.6 17.4 ng.g-1 in liver and <1.6 9.2 ng.g-1 in kidney. The low levels detected are related, especially, to the feeding habits of the species since C. mydas is mainly herbivore, and to a non industrialized sampling area.
9

Ocorrência de PCBs, PBDEs e pesticidas organiclorados em Prionace glauca da costa sul brasileira / Ocurrence of PCBs, PBDEs and organochlorine pesticides in Prionace glauca from Braziliam south coast

Cascaes, Mauro Juliano 29 June 2009 (has links)
Existem muitos estudos sobre a ocorrência de poluentes orgânicos persistentes (POPs) no ambiente marinho utilizando bioindicadores como os tubarões. Entretanto, no Brasil, ainda há carência de dados de POPs nesses organismos. O objetivo desta pesquisa foi investigar a ocorrência e o comportamento dos PCBs, pesticidas organoclorados e PBDEs no ambiente marinho, a partir da utilização dos tubarões como indicadores. Musculatura e fígado de vinte tubarões-azul (Prionace glauca) foram coletados em agostosetembro de 2008. Os PCBs foram os poluentes predominantes, presentes em 80% das amostras, com concentrações variando de <n.d. a 427,28 ng.g-1 de peso úmido. Os diclorodifeniletanos apresentaram concentrações variando de 0,43 a 202,42 ng.g-1 de peso úmido, no qual o 4,4´-DDE foi o composto mais significativo, com 77,6% de contribuição para os DDTs totais. As concentrações no fígado foram 1-2 ordens de grandeza mais elevadas, em relação às de musculatura. Houve um padrão de distribuição dos poluentes com níveis equivalentes entre indivíduos imaturos. Os machos maduros apresentaram concentrações de POPs sensivelmente maiores que as fêmeas maduras, indicando a transferência dos POPs para os filhotes. Os resultados demonstraram a ampla distribuição desses poluentes no ambiente marinho. / There are many studies about the occurrence of persistent organic pollutants (POPs) in the marine environment using sharks as bioindicators. However, there is still a lack of data of POPs in those organisms in Brazil. The goal of this research was to investigate the occurrence and behavior of PCBs, organochlorine pesticides and PBDEs in the marine environment, using sharks as indicators. Muscle and liver of twenty blue-sharks (Prionace glauca) were collected in august-september 2008. The PCBs were the predominant pollutants and being present in 80% of samples, with concentrations ranging from <n.d. to 427.28 ng.g-1 wet weight. The dichlorodiphenylethanes present concentrations ranging from 0.43 to 202.42 ng.g-1 wet weight, where the 4,4´-DDE was the most significative compound, with contributions of 77,6% of the total DDTs. The concentrations in the liver were 1-2 orders of magnitude higher than in the muscle. There was a distribution pattern of the pollutants, with equivalent levels among the immature specimens. The concentration of POP was significantly higher in the mature males and relatively lower in the mature female, showing the maternal transference of POPs to the pups. The results have demonstrated a wide distribution of these pollutants in the marine environment.
10

Determinação de pesticidas organoclorados em tecidos de tartarugas-verdes (Chelonia mydas) provenientes da costa sudeste do Brasil: estudo da ocorrência em animais com e sem fibropapilomatose / Determination of organochlorine pesticides in tissues of green turtles (Chelonia mydas) from the southeastern coast of Brazil: study of the occurrence in animals with and without fibropapillomatosis

Angelica Maria Sanchez Sarmiento 27 September 2013 (has links)
O aumento das intervenções antropogênicas, nos âmbitos marinho e costeiro representa grande risco aos ecossistemas de suporte de numerosas populações de animais como as tartarugas marinhas. Desequilíbrios no balanço ecológico desses habitats afetam negativamente a sobrevivência de quelônios de longa vida, como a Chelonia mydas, seriamente ameaçada de extinção. As ameaças à espécie incluem captura incidental por pesca, doenças e degradação dos habitats de alimentação e nidificação. Uma das principais doenças é a fibropapilomatose (FP) ou Green Turtle Fibropapiloma Disease (GTFD), afecção tumoral e de caráter infeccioso que acomete predominantemente espécimes juvenis. Numerosas hipóteses têm surgido a respeito da etiologia da doença, mas ainda nada é conclusivo. Contudo existe o consenso de que a etiologia da mesma seja \"multifatorial\" envolvendo um &#945;-herpesvírus como agente etiológico primário e a participação de diversos co-fatores genéticos, nutricionais e ambientais. No Brasil a prevalência média de FP en C. mydas varia conforme a região, existindo localidades nas quais não há registro da doença. O aumento da prevalência da FP tem sido implicada à degradação dos habitats marinhos, relacionado por sua vez a contaminantes ambientais como os organoclorados e seus metabólitos. Estes compostos caracterizam-se por serem altamente persistentes, bioacumulando e biomagnificando no ambiente marinho através do tempo. Além disso, são conhecidos por causarem inúmeros efeitos na saúde, interferindo na imunidade do indivíduo e favorecendo a manifestação de doenças, inclusive sendo apontados como agentes carcinogênicos. No presente trabalho foi desenvolvida uma técnica de extração e purificação baseada no método QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) para monitoramento pela cromatografia gasosa com captura de elétrons (GC-&mu;ECD) dos agrotóxicos clorados: &alpha;-BHC, &beta;-BHC, Heptacloro, Dicofol, &alpha;-Endosulfan, &beta;-endosulfan, Sulfato endosulfan, pp\' -DDD, op\' -DDD, pp\' -DDE, op\' -DDE e Mirex nos tecidos adiposo e hepático de 64 tartarugas-verdes juvenis (Cumprimento Curvo da Carapaça - CCC = 38,68±5,41cm) acometidas ou não pela FP (24 com FP vs. 40 sem FP), espécimes que vieram a óbito por captura incidental em redes de pesca ou foram encontradas encalhadas nas praias de Ubatuba/SP, Praia Grande/SP e Vitória/ES. Objetivou-se esclarecer possíveis correlações das suas concentrações com variáveis como sexo, tamanho (CCC), índice de condição corporal (ICC), severidade; índice de fibropapilomatose (FPI) e escore de fibropapilomatose (FPS) e ocorrência da doença em algumas localidades da região sudeste do país com diferentes taxas de prevalência da FP, na tentativa de inferir o papel dos mesmos na patogenia desta afecção. Foi observada correlação significativa entre a porcentagem lipídica entre as amostras dos tecidos adiposo e hepático, assim como entre a concentração total de organoclorados (&#931;OCS) nos tecidos adiposo e hepático. Embora observadas algumas diferenças na presença ou ausência de alguns contaminantes, estas foram dispersas e não determinantes, ou seja, não permitiram estabelecer um padrão em relação aos diferentes fatores do histórico individual. Não foram encontradas diferenças significativas entre a &#931;OCS para ambos os tecidos, em relação ao sexo do animal ou localidade, que permitissem inferir alguma relação entre o grau de contaminação e a variação regional da prevalência da FP. Também não foi possível identificar correlações significativas das concentrações dos poluentes em relação à presença da FP nem entre o FPI e o FPS e a &#931;OCS nos tecidos adiposo e hepático. Tampouco foi possível identificar correlações significativas entre o ICC ou CCC e a &#931;OCS. Os resultados deste trabalho apresentam um registro temporal do perfil de contaminação nas tartarugas-verdes de vida livre da costa sudeste, confirmando a biodisponibilidade de OCs nas diferentes regiões avaliadas. Embora não tenha sido encontrada uma correlação direta entre a concentração de OCs e a Fibropapilomatose, este estudo demonstra que as tartarugas verdes oriundas da costa sudeste do Brasil estão expostas a níveis significativos de pesticidas organoclorados os quais poderiam ter algum papel na etiologia multifatorial da doença. Estes contaminantes ambientais podem agir afetando a taxa de prevalência de FP, agindo possivelmente como agentes imunossupresores ou através da genotoxicidade e promoção tumoral. Estudos futuros serão desenvolvidos para melhor caracterizar a ação dessas substâncias e seus efeitos nas tartarugas marinhas e para esclarecer como outros fatores podem influenciar esses resultados. / The increase of anthropogenic impacts on both marine and coastal environments is threatening the ecosystems of numerous animal populations, including sea turtles. Disturbances in the ecological balance of these habitats negatively affect the survival of longlived chelonids such as green turtles (Chelonia mydas), which are already considered endangered. Threats to this species include incidental capture by fisheries, habitat degradation of nesting and feeding areas, and diseases. One of the most relevant diseases is fibropapillomatosis (FP) or Green Turtle Fibropapilloma Disease (GTFD), an infectious tumoral disease that predominantly affects juveniles. Numerous hypotheses have been proposed to explain this diseases aetiology, and while none has been conclusively demonstrated there is a consensus that it is multifactorial and involves a -herpesvirus as the primary etiologic agent along with genetic, nutritional and environmental cofactors. The prevalence of FP in C. mydas in Brazil varies among regions, with locations in which the disease remains unreported. Prevalence has been correlated to the degree of degradation of marine habitats, which in turn is related to the presence of environmental contaminants such as organochlorines and their metabolites. These compounds are difficult to break down and persist, bioaccumulate and biomagnify in marine environments over long periods of time. They are also known to produce numerous health effects in the organisms in which they accumulate, hampering immunity and favouring the manifestation of opportunistic disease, with some of these compounds being also carcinogens. In this study we developed extraction and purification technique based on the QuEChERS method (Quick, Easy, Cheap, Effective, Rugged and Safe) and used gas chromatography with electron capture (GC-&mu;ECD) to detect and quantify organochlorine (&alpha;-BHC, &beta;-BHC, Heptachlor, Dicofol, &alpha;-endosulfan, &beta;-endosulfan, Endosulfan sulphate, pp\' -DDD, op\' -DDD, pp\' -DDE, op\' -DDE, and Mirex) in adipose and hepatic tissue samples from 64 juvenile green sea turtles [Curved Carapace Length - CCL = 38.68 ± 5.41 cm] affected or not by FP (24 with FP vs. 40 without FP). These specimens died due to incidental capture by fishing nets or were found dead on beaches of Southeast Brazil: Ubatuba / SP, Praia Grande / SP and Vitória / ES. Aiming to clarify the role of the organochlorines in the pathogenesis of FP, we attempted to establish correlations between the concentration of these compounds and variables such as sex, size (CCL), Body Condition Index (BCI) and disease severity [fibropapillomatosis index (FPI) and fibropapillomatosis score (FPS)], and local FP prevalence. A significant correlation was observed between the lipid percentage of adipose and hepatic samples, as well as between adipose and hepatic organochlorine total concentrations (&#931;OCS). Although some differences were observed regarding the presence or absence of contaminants in relation to characteristics of the individual history, it was not possible to establish patterns that reflected biological significance. For both adipose and hepatic tissues, no significant differences were found in the &#931;OCS with regards to individual sex or capture locality that would allow inferring relationships between the individual contamination levels and the regional variation on the prevalence of FP. It was also not possible to identify significant relationships between each pollutant concentration in the adipose or hepatic tissue and the presence of FP. No correlation was observed between &#931;OCS in adipose or hepatic tissues and FPI, FPS, BCI and CCL. The results provide a contamination profile of free-ranging green turtles of the southeast coast during the study period, confirming the bioavailability of OCs in the different locations evaluated. Although a direct correlation between the concentration of OCs and fibropapillomatosis was not found, this study demonstrates that green turtles from the southeast coast of Brazil are exposed to significant levels of organochlorine pesticides that could play a role in the multifactorial etiology of the disease. These contaminants may affect the prevalence of FP, possibly acting as immunosuppressive agents or through genotoxicity and tumor promotion. Future studies will be conducted to better characterize the role of these substances and their effects on sea turtles and to clarify how other factors that may influence their impacts.

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