Dissertations / Theses on the topic 'Organochlorines pesticides'

The aim of this study is to assess the biological accumulation of pesticide residues in aquatic organisms in Sai Gon - Dong Nai (SG-DN) estuary. Fish and mollusks were collected directly at the Soai Rap and Long Tau estuary of the SG-DN river system, washed and separated for taking the tissue. The organochlorine compounds from the tissue were then extracted and analyzed by gas chromatography system. The results showed that, the concentration of OCPs in Tegillarca granosa, Meretrix lyrata, Margaritifera auricularia and Bostrychus sinensis varied from 6.4 to 59.9 μg/kg, 7.2 to 322 μg/kg, 4.5 to 62.1 μg/kg and 2.9 to 114.3 μg/kg fresh weight, respectively. In general, molluscs species that accumulate more heptachlor, aldrin, endrin or dieldrin tend to accumulate less DDT (dichlorodiphenyltrichloroethane). Endosulfan was the most commonly found in three bivalve mollusks while DDTs (1.5–75.2 μg/kg, averaging 8.7 μg/kg weight) was the most popular OCPs in the fish (Bostrychus sinensis) samples. In DDT group, the p,p’-DDT metabolite accounted for the largest percentage, reaching 50% of total DDTs. In HCH (Hexachlorocyclohexane) group, β-HCH isomer was predominant in almost samples.
Mgr đích ccc nghiên cch này là đánh giá tích lũy sinh hhn ccn thuu trr sâu trong các sinh vvn ssnh dưưh nưưh ttư khu vvu ccu sông Sài Gòn - ĐĐn Nai (SG-DN). Cá và nhuyyu thh đưưy llư trry tiiy iicửa sông Soài RRà và Lòng Tàu thuu hh thhu sông SG-DN, đư-D rư- ss-D và tách llc phhh mô thht. Các hhc chh clo hho cơ sau đó đưưđ tách chii và phân tích bbch hh thhh ssh ký khí. Kết quả nghiên cứu cho thấy, dư lượng OCPs tích tụ trong sò điệp (Tegillarca granosa), ngao (Meretrix lyrata), trai nước ngọt (Margaritifera auricularia) và cá bớp (Bostrychus sinensis) dao động tương ứng từ 6,4 đến 59,9 μg/kg, 7,2 đến 322 μg/kg, 4,5 đến 62,1 μg/kg và 2,9 đến 114,3 μg/kg trọng lượng tươi. Nhìn chung, loài nhuyễn thể nào tích lũy nhiều heptachlor, aldrin, endrin hoăc dieldrin có xu hướng tích lũy ít DDT (Dichlorodiphenyltrichloroethane). Endosunfan là nhóm thuốc được tìm thấy nhiều nhất trong các loài nhuyễn thể nghiên cứu. Ngược lại, nhóm DDT lại phổ biến ở cá Bostrychus sinensis (1.5–75.2 μg/kg, trung bình 8.7 μg/kg trọng lượng). Dạng p.p’-DDT trong nhóm DDT chiếm tỷ lệ cao nhất, tới 50% DDT tổng. Trong khi đó, đồng dạng β-HCH của nhóm HCH (Hexachlorocyclohexane) chiếm đa số trong hầu hết các mẫu.

Altered immune responses have been observed following occupational, inadvertent, or therapeutic exposure to xenobiotics. Many pesticides are known to cause immunotoxicity. Exposure to mixtures of pesticides, either concurrently or sequentially, may result in potentiating this effect partly because one can effect the metabolism of the other. The objective of this study was to determine the effect of the insecticides endosulfan, permethrin and their mixtures on C57/BL6 male mice thymocytes in vitro and to ascertain the mechanism by which these effects take place. Permethrin, a broad-spectrum synthetic pyrethroid, is a widely used insecticide in agriculture and public health. Endosulfan is a highly toxic chlorinated hydrocarbon insecticide used worldwide. We examined the immunotoxic potential of these pesticides using a flow cytometric technique in combination with 7-Amino Actinomycin D (7AAD) to distinguish live, early apoptotic, and late apoptotic/necrotic cells. DNA ladder assay, a hallmark of apoptosis , was also used to determine the occurrence of apoptosis. Both endosulfan and permethrin were found to cause significant apoptotic death of thymocytes in a dose- and time- dependent manner. Thus, permethrin at 50, 100 or 300 µM was found to cause 5.5, 11.5 and 26.1% increases in early apoptotic cell death relative to control, respectively. Endosulfan at 25, 50 or 250 µM was found to cause 11.9, 15.7 and 68.0% early apoptotic cell death, respectively. For the mixture study, concentrations of 100 µM permethrin and 50 µM endosulfan were selected and found to cause 27.1% apoptosis. Thus, these pesticides in mixture have an additive immunotoxic effect. Increases in late-apoptotic/necrotic cells were found at these concentrations for either pesticide when exposed for 12 hours. DNA ladder assay confirmed the presence of DNA fragments and therefore the presence of significant apoptotic cell death. Apoptosis is a morphologically distinct form of cell death that can be mediated by a variety of pathological and physiological stimuli. Because permethrin and endosulfan were found to induce apoptosis in C57/BL6 mice thymocytes in vitro, the objective of the second half of this study was to elucidate the potential mechanism by which these pesticides regulate apoptosis in immune cells. Caspases are a family of cystine-dependent, aspartate-directed proteases that have an integral role in apoptotic cell death. Caspases, which are normally inactive in healthy cells, are activated during apoptosis and form an irreversible cascade. There are two subsets of caspases, initiator caspases (i.e. caspase 8 and 9) and effector caspases (i.e. caspases 3 and 6). Caspase 3, a downstream effector of apoptosis, is activated by many different pathways and is an apoptotic marker in cells. Caspase 8 is the apical caspase in the extrinsic pathway. Caspase 9 is the apical caspase in the intrinsic pathway, therefore we investigated mechanisms of pesticide induced apoptosis involving the thymocyte caspase system. Thymocytes from C57/BL6 mice were incubated with varying concentrations of pesticides for varying amounts of time. Active caspase 3 was then measured using EnzCheck Caspase 3 Assay Kit. Relative fluorescence for permethrin exposed cells after 12 hours incubation in the presence of pesticides at 150, 100, and 50 µM and 40 minutes in the presence of AFC-substrate was found to be 387, 386, and 297, respectively. Relative fluorescence for endosulfan exposed cells at 150, 100 and 50 µM was 188, 177, and 294. Caspase 3 activity increased as permethrin concentrations increased and decreased as endosulfan concentrations were increased. Then the extrinsic and intrinsic pathways of apoptosis were further investigated. Active caspase 8 was measured using the ApoAlert Caspase Fluorescent Assay Kit. Relative fluorescence for permethrin exposed cells after 7 hours incubation in the presence of pesticides at 100, 150, and 200 µM was found to be 35.5, 10.5, and 0, respectively. Relative fluorescence for endosulfan exposed cells after 7 hours incubation at 25, 50, 100 and 150 µM was found to be 32.8, 63.8, 69.5, and 55.5, respectively. A mixture study was then performed using endosulfan (50, 100, 150 µM) combined with permethrin (100 µM). All combinations were found to have more than an additive effect, therefore the extrinsic pathway seems to be involved. Caspase 9 activity was measured using Caspase 9/Mch6 Fluorometric Protease Assay Kit. Relative fluorescence for endosulfan exposed cells after 7 hours incubation at 25, 50, 100 and 150 µM was found to be 43, 73, 78.9, and 5.12, respectively. Relative Fluorescence for permethrin exposed cells at 100, 150 and 200 µM was found to be 34.5, 39, and 55.5, respectively. A mixture study was then performed using endosulfan (25, 50 µM) combined with permethrin (100 µM). Both combinations were found to have less than an additive effect. These results suggest that apoptosis caused by both endosulfan and permethrin exert their effects via the caspase pathway. The results also show that mixtures of pesticides have a less than additive effect on caspase 9 activation and more than an additive effect on caspase 8 activation, therefore the extrinsic pathway is predominantly involved in thymocyte apoptosis caused by mixtures of permethrin and endosulfan.
Master of Science

Doutoramento em Biologia
As tartarugas marinhas sofrem um forte impacto populacional devido às atividades antropogênicas, como as causadas pelo aumento da exploração comercial e industrial nas áreas costeiras, alteração do habitat, ingestão de resíduos sólidos, captura acidental nas atividades pesqueiras e a contaminação de poluentes químicos. Das sete espécies de tartarugas marinhas existentes distribuídas por quase todos os oceanos (Caretta caretta, Chelonia mydas, Dermochelys coriacea, Eretmochelys imbricata, Lepidochelys olivacea, Natator depressus e Lepidochelys kempii), exceto o Natator depressus, todos os outros seis são listados como vulneráveis, em perigo ou criticamente ameaçado na lista da IUCN. Os contaminantes ambientais de origem química, como metais pesados, pesticidas, hidrocarbonetos, PCB, organoclorados e dioxinas estão causando um forte impacto na saúde de animais marinhos, incluindo tartarugas marinhas, e a bioacumulação desses poluentes em tecidos e órgãos influenciam o crescimento e desenvolvimento de populações naturais de tartarugas marinhas em todo o mundo, podendo causar mortalidade em vários estágios de seu desenvolvimento. Uma vez que estão em perigo é extremamente importante para a compreensão das respostas às medidas de impacto e conservação à longo prazo nas populações de tartarugas marinhas. Este trabalho é uma visão geral dos estudos sobre a quantificação de contaminantes em ovos e sangue de tartarugas marinhas, buscando relações entre o tamanho da carapaça e a atividade de enzimas antioxidantes usando técnicas não-letais. A concentração de pesticidas organoclorados (OCPs) no plasma das fêmeas adultas e os ovos das tartarugas de pente (Eretmochelys imbricata) e tartaruga verde (Chelonia mydas) que desovam na área costeira de Campeche serão analisados. O objetivo principal desta tese é avaliar o potencial das populações naturais como bioindicadores de contaminação química. Para tal, foram analisados os valores hematológicos, contaminação de OCPs no plasma e ovos de duas espécies de tartarugas marinhas com hábitos alimentares diferentes e uma possível transferência materna na espécie de tartaruga de pente. Por fim, a atividade de biomarcadores enzimáticos foram correlacionadas com a contaminação por OCPs. Os resultados mostraram que foram encontrados OCPs em todos os ovos analisados, mostrando maiores concentrações de ΣHCH e ΣDrines nas duas espécies selecionadas, sendo encontradas diferenças significativas entre as espécies e os anos analisados. Foram encontras diferenças significativas entre as concentrações de OCPs (ΣHCHs, ΣDrines e ΣChlordanes) em relação ao sangue e ovos, indicaram que esses contaminantes químicos estão sendo transferidos maternalmente. Nenhuma enzima antioxidante teve relação significativa com os OCPs mais encontrados no sangue (ΣDDTs, ΣHCHs e ΣDrines).
Sea turtles have been suffering strong population impact due to anthropogenic activities, such as those caused by the increase in commercial and industrial exploitation of coastal areas, habitat alteration, ingestion of solid waste, incidental capture in fishing activities and contamination of chemical pollutants. Of the seven species of marine turtles existing distributed by almost all oceans (Caretta caretta, Chelonia mydas, Dermochelys coriacea, Eretmochelys imbricata, Lepidochelys olivacea, Natator depressus and Lepidochelys kempii), except the Natator depressus, all other six are listed as vulnerable, endangered or critically endangered on the IUCN list. Environmental contaminants of chemical origin such as heavy metals, pesticides, hydrocarbons, PCBs, organochlorine, and dioxins are causing major health impacts of marine animals, including sea turtles, and bioaccumulation of these pollutants in tissues and organs influence the growth and development of natural populations of sea turtles worldwide, may cause mortality in various stages of development. Because they are endangered is extremely important to the understanding of responses to impact and conservation measures in the long term in the populations of sea turtles in developing. This work is an overview of studies on the quantification of contaminants in blood and sea turtle eggs, searching for relationships between, carapace size and the activity of antioxidant enzymes using non-lethal techniques. The concentration of organochlorine pesticides (OCPs) in plasma of adult females and eggs of hawksbill turtles (Eretmochelys imbricata) and green turtle (Chelonia mydas) that nest in the coastal area of Campeche will be analysed. The main objective of this thesis is to evaluate the potential of natural populations as bioindicators of chemical contamination. For this, the hematological values, contamination of OCPs in the plasma and eggs of two species of sea turtles with different feeding habits and a possible maternal transfer in the hawksbill turtles were analysed. Finally, the activity of enzymatic biomarkers was correlated with the contamination by OCPs. The results showed that OCPs were found in all analysed eggs, showing higher concentrations of ΣHCH and ΣDrines in the two species selected, being found significant differences between the species and the studied years. We find significant differences between the concentrations of OCPs (ΣHCHs, ΣDrines and ΣChlordanes) of blood to eggs showed that these chemical contaminants being transferred maternally. No antioxidant enzyme had significant relationship with COPs main found in the blood (ΣDDTs, ΣHCHs and ΣDrines).

Previous monitoring studies by federal agencies such as the United States Geological Survey have shown that environmental contaminants rarely occur as single compounds but, rather, as mixtures. In aquatic ecosystems, mixtures of these compounds are often complex, sometimes containing dozens of compounds across a number of different chemical classes. Non-target aquatic organisms are frequently exposed to varying levels of contaminants based upon the physical properties of the chemicals, such as water solubility, and life-cycle habits of the individual organisms. In addition to this, past research has indicated that the presence of one class of contaminant may have an influence on the toxicities of other chemical classes. Water-only toxicity testing has historically provided a means by which researchers can rapidly determine the toxic effects of water-soluble compounds such as triazine herbicides and organophosphate insecticides. However, many legacy pesticides, such as organochlorine, and some current-use pesticides, such as pyrethroids, are strongly hydrophobic, and suspended or bedded sediments, rather than water, would generally be more appropriate matrices for monitoring. Yet sampling of sediments and quantification of residues of these pesticides is often lacking. Similarly, there have been few studies examining the toxicity of mixtures of these compounds in sediment. The first goal of this research was to examine the effects of select triazine herbicides on organophosphate insecticide toxicity utilizing water-only toxicity test with the aquatic amphipod Hyalella azteca. The second goal was to analyze an existing database of chemical concentrations using a toxicity-based screening approach in order to estimate the environmental hazard posed by mixtures of pyrethroid, organochlorine, and organophosphate insecticides in sediment to H. azteca. The third goal of this research was to examine the toxic effects of mixtures of different pyrethroid insecticides to H. azteca using compounds identified as most relevant from the screening phase of the study. The fourth goal of this research was to examine how pyrethroid and organochlorine insecticides partition between different size fractions within sediment and detritus, as well as between sediments with differing organic carbon content, and the resulting effects to compound toxicity and bioavailability. The final goal of this research was to examine potential modifications to bifenthrin sediment partitioning, toxicity, and bioaccessibility resulting from various dissolved salt concentrations in overlying water using H. azteca and Chironomus dilutus as reference organisms. Together, the individual objectives of this study provide a thorough and multi-tiered approach to determining the occurrence, environmental fate, biological effects, and bioavailability of frequently detected and co-occurring environmental contaminants in both agricultural and urban landscapes.

Os albatrozes e petréis (Procellariiformes) são aves oceânicas e migratórias de grande interesse conservacionista. Neste trabalho foram estudadas duas classes de poluentes bastante conhecidos por afetarem negativamente as aves marinhas: os poluentes orgânicos persistentes e os plásticos. Bifenilos policlorados (PCBs) e pesticidas organoclorados foram detectados no tecido adiposo, fígado e músculo de oito espécies de Procellariiformes. Apesar da grande variabilidade intraespecífica nas concentrações, os perfis de PCBs e pesticidas organoclorados foram semelhantes entre os indíviduos, com predôminância de PCBs penta, hexa e heptaclorados e do p´p-DDE. A condição corporal se mostrou um fator importante na variação e redistribuição dos organoclorados nos tecidos das aves. As análises de isótopos estáveis de carbono e nitrogênio no fígado e músculo das aves mostraram que a dieta não foi suficiente para explicar as concentrações de organoclorados nas espécies estudadas e reforçaram a influência de fatores como idade, distribuição e especifidade da dieta na contaminação por estes compostos em aves marinhas. PCBs e pesticidas organoclorados foram detectados em pellets e fragmentos plásticos encontrados no trato digestório das aves estudadas, com perfis semelhantes aos encontrados nos tecidos dos Procellariiformes. A ocorrência de poluentes orgânicos em plásticos evidencia a capacidade destes de adsorver e transportar estes compostos e reforça o potencial dos plásticos como uma fonte adicional de contaminação para os animais que os ingerem, como as aves marinhas.
Albatrosses and petrels (Procellariiformes) are migratory oceanic birds of considerable conservational interest. The aim of the present study was to evaluate two classes of pollutants that negatively affect seabirds: persistent organic pollutants and plastics. Polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) were detected in the adipose tissue, liver and muscle of eight species of Procellariiformes. Although organochlorine concentrations exhibited a high degree of intra-species variability, the profiles of PCBs and OCPs were similar among the individuals, with predominance of penta, hexa and heptachlorobiphenyls and p´p-DDE. Body condition was an important factor in the variation and redistribution of organochlorine compounds in the tissues of the birds. Stable isotope analysis of carbon and nitrogen in the liver and muscle revealed that diet alone was insufficient to explain the organochlorine concentrations in the species studied, suggesting the influence of factors such as age, distribution and diet specificity regarding organochlorine contamination in seabirds. PCBs and OCPs were detected in plastic fragments and pellets found in the digestive tract of Procellariiformes, with profiles very similar to those found in the tissues of the birds. The occurrence of organic pollutants in plastics demonstrates their ability to adsorb and transport these compounds and underscores the potential of plastics as an additional source of contamination in organisms that ingest these products, such as seabirds.

Ce travail s’intéresse à évaluer l’efficacité de procédés d’oxydation avancée pour l’élimination de pesticides dans l’eau, plus particulièrement l’acide 2,4-dichlorophénoxyacétique (2,4-D), un herbicide largement répandu, qui a été récemment classé comme cancérogène possible pour l’homme. Ces procédés utilisent différents types de rayonnement – UV/visible, ultrasons, rayons gamma –, seuls ou en combinaison avec des oxydants et/ou catalyseurs (ozone, peroxyde d’hydrogène, réactif de Fenton). L'influence du pH, de la dose d'oxydant, du type et de la concentration du catalyseur, du spectre d'irradiation lumineuse, de la dose de rayons gamma et de la fréquence ultrasonore est également analysée, de façon à déterminer par plans d’expériences les plages de fonctionnement optimales pour la conversion et la minéralisation du polluant. Parmi les procédés individuels, seules l’ozonation et l’oxydation Fenton homogène d’une part, la photolyse et l’irradiation gamma d’autre part permettent d’éliminer plus de 25% du carbone organique total en 1 heure. La sonolyse (à haute fréquence) apparaît comme le traitement moins performant, avec une dégradation du 2,4-D inférieure à 15% sur la même durée. Par ailleurs, des effets synergiques marqués sont mis en évidence en associant les différents types de rayonnement avec H2O2 ou le réactif de Fenton. Dans le dernier cas, le polluant est décomposé en moins de 10 minutes, tandis que le rendement de minéralisation est plus que doublé par rapport aux procédés séparés. Il en est de même pour le procédé couplé UV/O3 par rapport à l’ozonation et la photolyse seules. Ramenés à leur consommation énergétique, les traitements les plus efficaces sont, respectivement en termes de conversion et de minéralisation, l’oxydation radio-Fenton et l’oxydation photo-Fenton utilisant une lampe UV à basse pression de mercure. Par ailleurs, contrairement à la photolyse, ce dernier procédé est également activé par une lampe à arc Xenon, dont le spectre d’émission est proche de celui de la lumière du soleil. Sur la base de ces résultats, un photo-réacteur solaire à recirculation est mis en oeuvre pour traiter par oxydation photo-Fenton homogène des solutions de 2,4-D, préparées dans l’eau du robinet ou une eau résiduaire en entrée de station d’épuration. Dans les deux cas, la conversion du pesticide dépasse 95% en 1 heure et sa minéralisation 75% en 5 heures. Par ailleurs, l’eau ainsi traitée respecte tous les paramètres de qualité établis par la norme cubaine de rejet des eaux usées, en incluant une étape successive de neutralisation avec Ca(OH)2 et de filtration. Enfin, plusieurs parmi les meilleurs procédés sont évalués pour éliminer deux autres pesticides organochlorés, particulièrement toxiques et persistants dans l’environnement : le chlordécone et le bêta-hexachlorocyclohexane. Des résultats encourageants sont obtenus, avec une dégradation pratiquement totale des polluants en cinq heures, ce qui démontre l’intérêt des méthodes étudiées pour cette problématique
This work investigates the efficacy of advanced oxidation processes for the remediation of pesticidesin water, more particularly 2,4-dichlorophenoxyacetic acid (2,4-D), a widely used herbicide that hasrecently been classified as a possible carcinogen to humans. These methods use different types ofradiation - UV / visible, ultrasound, gamma rays - alone or in combination with oxidants and / orcatalysts (ozone, hydrogen peroxide, Fenton’s reagent). The influence of pH, oxidant dose, catalysttype and concentration, light irradiation spectrum, gamma radiation dose and ultrasound frequencyis also analyzed, in order to determine by experimental design the optimal operating ranges for theconversion and mineralization of the pollutant. Of individual processes, only ozonation andhomogeneous Fenton oxidation on the one hand, photolysis and gamma irradiation on the otherhand, achieve the abatement of more than 25% of total organic carbon in one hour. (High frequency)sonolysis appears as the less efficient treatment, resulting in less than 15% of 2,4-D being degradedover the same duration.In addition, marked synergistic effects are demonstrated by combining the different types of radiationwith H2O2 or Fenton’s reagent. In the latter case, the pollutant is decomposed in less than 10 minutes,while the mineralization yield more than doubles compared to the separate processes. It is the samefor UV/O3 coupled process with respect to ozonation and photolysis alone. When accounting for theirenergy consumption, the most effective treatments are, respectively in terms of conversion andmineralization, radio-Fenton oxidation and photo-Fenton oxidation using a low-pressure mercuryvaporUV lamp. Moreover, unlike photolysis, the latter method is also activated by a Xenon arc lamp,whose emission spectrum is close to that of sunlight. Bases on these results, a solar photoreactoroperating in closed loop is used to treat 2,4-D solutions, prepared with tap water or inlet stream ofwastewater treatment plant, by homogeneous photo-Fenton oxidation. In both cases, the conversionof the pesticide exceeds 95% in 1 hour and its mineralization 75% in 5 hours. Moreover, the treatedwater complies with all the quality parameters established by the Cuban norm for wastewaterdischarge, when including a subsequent step of neutralization with Ca(OH)2 and filtration.Finally, several of the best processes are evaluated to eliminate two other organochlorine pesticides,particularly toxic and persistent in the environment: chlordecone and beta-hexachlorocyclohexane.Encouraging results are obtained, with an almost complete degradation of the pollutants in fivehours, which demonstrates the value of the investigated methods for this issue
En este trabajo se estudió la factibilidad de diferentes procesos avanzados de oxidación para laeliminación de plaguicidas en aguas, específicamente el ácido 2,4-diclorofenoxiacético (2,4-D), unode los herbicidas más utilizados a nivel mundial y que recientemente ha sido clasificado comocancerígeno para el hombre. Estos procesos utilizan diferentes tipos de irradiación – UV/Visible,ultrasonido, radiación gamma – solos o en combinación con oxidantes y/o catalizadores (ozono,peróxido de hidrógeno, reactivo de Fenton). Con el objetivo de determinar las condiciones óptimaspara la degradación y mineralización del contaminante, se analizó la influencia del pH, la dosis deoxidante, el tipo y la concentración del catalizador, el espectro de irradiación luminosa, la dosis deirradiación gamma y la frecuencia y potencia ultrasónicas. Entre los procesos individuales,solamente la oxidación Fenton homogénea, la ozonización, la fotólisis y la radiación gamma lograroneliminar más de un 25% del carbono orgánico total en una hora. La sonólisis (a alta frecuencia)resultó el proceso menos eficiente, con una degradación del 2,4-D inferior al 15% en el mismotiempo.Al asociar los diferentes tipos de irradiación con el H2O2 o el reactivo de Fenton, se observaronefectos sinérgicos importantes. Para este último, el contaminante se degradó totalmente en menosde 10 minutos, mientras que la mineralización fue superior al doble de la obtenida para los procesospor separado. Lo mismo ocurrió para el proceso combinado UV/O3, respecto a los procesos defotólisis y ozonización solos. Teniendo en cuenta el consumo energético asociado a la degradacióny mineralización respectivamente, los tratamientos más eficientes fueron el radio-Fenton y el foto-Fenton utilizando una lámpara de baja presión de mercurio. Por otra parte, al contrario de la fotólisis,este último proceso se activó con una lámpara de arco de Xenon, la cual posee un espectro deemisión cercano a la luz solar. Teniendo en cuenta estos resultados, se realizó un grupo deexperimentos a escala de banco utilizando un foto-reactor solar, donde se trataron por oxidaciónfoto-Fenton homogénea disoluciones de 2,4-D preparadas con agua técnica y agua residualobtenida a la entrada de una planta de tratamiento de aguas. En los dos casos, la degradación delpesticida supera el 95% en 1 hora y su mineralización en 75% en 5 horas. Además, al incluir unaetapa de neutralización con Ca(OH)2, el agua residual tratada logra cumplir las normas de calidadestablecidas por la norma cubana de vertimiento de aguas residuales.Finalmente, algunos de los procesos con mejores resultados se evaluaron para la eliminación otrosdos pesticidas organoclorados de mayor toxicidad y persistencia en el medio ambiente: laclordecona y el beta hexaclorociclohexano. Al aplicar las técnicas de tratamiento a estoscompuestos se lograron buenos resultados, cercanos a la degradación total de ambos plaguicidasen cinco horas, lo que demuestra el interés de los métodos estudiados en esta tesis

Introduction Epidemiologic data supporting the role of organochlorine pesticides in pubertal development are limited. Methods Using a nested case-control design, serum collected during pregnancy from mothers of 218 girls who reported menarche before 11.5 years of age (cases) and 230 girls who reported menarche at or after 11.5 years of age (controls) was analyzed for 9 organochlorines and metabolites. We analyzed the association between in utero organochlorine concentrations and early menarche using multivariate logistic regression controlling for mother's age at menarche, or mother's prenatal BMI. Results We did not observe an association between in utero exposure to HCB, β-HCH, ϒ-HCH, p,p′-DDT, p,p′-DDE, oxychlordane or trans-nonachlor and early menarche. Conclusions This study is the first to examine the association between in utero exposure to HCB, β-HCH, ϒ-HCH, oxychlordane or trans-nonachlor and early menarche. In utero exposure to organochlorine pesticides does not appear to have a role in the timing of menarche in this study.

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A maior parte dos pesticidas organoclorados (OCPs) possuem comercialização controlada ou proibida a décadas, no entanto são ainda encontrados em todos os locais do planeta. A determinação destes compostos em matrizes complexas como tecido de peixe é alvo constante de pesquisas, especialmente com o objetivo de minimizar consumo de reagentes e tempo. Este estudo objetivou desenvolver e validar um método QuECheRS com ultrassom e d-SPE para determinação por CG/ECD/MS de p,p’-DDE, p,p’-DDT, α-endosulfan, β-endosulfan, Aldrin e Dieldrin em tecidos de peixe, aplicar em amostras de tecidos de peixe comercializadas e em tecidos coletados em ambiente natural e realizar uma avaliação de risco das concentrações de OCPs detectadas nos tecidos. Três planejamentos fatoriais foram empregados para otimizar a etapa de preparo da amostra. O método desenvolvido foi validado para verificar seu desempenho e um possível efeito matriz, sendo posteriormente aplicado na extração de OCPs de músculo de Tilápia e Lambari comercializados em supermercados de Ponta Grossa e em músculo, ovas e vísceras de Lambari coletado da represa de Alagados, em Ponta Grossa. Ao final realizou-se uma avaliação de risco relacionando o consumo diário local, com massa corporal média da população e contaminação por OCPs nos tecidos analisados. Na validação o método apresentou recuperações entre 77,3% e 110,8%, com RSD inferior a 13% e os limites de detecção estiveram entre 0,24 μgkg-1 e 2,88μgkg-1, mostrando boa sensibilidade e precisão. Resíduos dos OCPs estudados foram detectados nos tecidos analisados em concentrações que variaram entre 3,4 μgkg-1 e 417,6 μgkg-1, verificando-se que os poluentes possuem uma tendência a bioacumular em maior proporção nas vísceras, do que em ovas e no músculo, a presença destes compostos nas ovas, demonstra que indivíduos da espécie analisada entram em contato com os OCPs desde a fase de embrião. Na avaliação de risco verificou-se que ao se consumir esses peixes, esses OCPs podem ao longo do tempo gerar efeitos adversos para a saúde dos consumidores. O método proposto mostrou-se efetivo na determinação de baixas concentrações de OCPs em tecidos de peixe, utilizando pequena massa de amostra (0,5 gramas), viabilizando a análise sem a necessidade de agrupamento (pool), ao mesmo tempo possibilitou a análise de tecidos, de peixe de pequena massa corporal total (Lambari), avaliando ainda a bioacumulação dos OCPs em diferentes tecidos. O método é aplicável para análise de OCPs aplicado à área toxicológica.
Most organochlorine pesticides (OCPs) are controlled or banned for decades, but they are still found everywhere in the world. The determination of these compounds in complex matrices such as fish tissue is a constant goal of research, especially with the aim of minimizing reagent consumption and time. The aim of this study was to develop and validate a Quechers method with ultrasound and d-SPE for determination of p, p'-DDE, p, p'-DDT, α-endosulfan, β-endosulfan, Aldrin and Dieldrin in fish tissues, apply on samples of commercially available fish tissues and on tissues collected in the natural environment and carry out a risk assessment of the concentrations of OCPs detected in the tissues. Three factorial designs were used to optimize the preparation stage of the sample. The method developed was validated through figures of merit and matrix effect, and it was later applied in the extraction of OCPs from Tilapia and Lambari muscle marketed in supermarkets in Ponta Grossa and Lambari muscle, eggs and viscera collected from the Alagados dam in Ponta Thick. At the end of the study, a risk assessment was performed relating local daily consumption, mean body mass of the population and OCP contamination in the tissues analyzed. In the validation, the method presented recoveries between 77.3% and 110.8%, with RSD lower than 13% and detection limits between 0.24 μg kg -1 and 2.88 μg kg -1, showing good sensitivity and precision. Residues of the OCPs studied were detected in the tissues analyzed at concentrations ranging from 3.4 μgkg-1 to 417.6 μgkg-1, with pollutants having a tendency to bioaccumulate more in the viscera than in roe and in muscle, the presence of these compounds in the eggs, demonstrates that individuals of the analyzed species come into contact with OCPs from the embryo stage. In the risk assessment it was found that there is a risk when consuming these fish, these OCPs may over time generate adverse effects on the health of consumers. The proposed method was effective in the determination of low concentrations of OCPs in fish tissues, using a small sample mass (0.5 grams), making the analysis possible without the necessity of pooling, at the same time making possible the analysis of tissues, of fish of small total body mass (Lambari), also evaluating the bioaccumulation of OCPs in different tissues. The method is promising for OCP analysis applied to the toxicological area.

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Este trabalho apresenta a caracterização geoambiental de solos de uma área contaminada, localizada no município de Santo André, Estado de São Paulo, Brasil. O objetivo foi determinar parâmetros experimentais para permitir o estudo de alguns aspectos do transporte do pesticida organoclorado Hexaclorociclohexano (HCH). A área de estudo contém células com cerca de 30.000 toneladas de um material contendo HCH em elevadas concentrações. As investigações de campo demonstram que há concentrações de HCH na água subterrânea. Em 2011, foram coletadas amostras deformadas e indeformadas de solo em quatro diferentes pontos superficiais da área contaminada, e posteriormente uma amostra composta da camada de solo de alteração de rocha (SAR), a fim de responder a questionamentos quanto à mobilidade do contaminante na área. A caracterização geoambiental, baseada em ensaios laboratoriais, foi realizada por meio das seguintes análises: análise granulométrica, limites de Atterberg, densidade específica, porosidade, umidade do solo, curva de retenção de água no solo, condutividade hidráulica, ensaio de adsorção, pH, condutividade elétrica, capacidade de troca catiônica (CTC), teor de matéria orgânica e teor de voláteis. O solo superficial da área é heterogêneo e a capacidade de adsorção dos solos analisados foi menor do que o esperado. Esta caracterização subsidiou o estudo de fluxo e transporte do HCH, por meio de simulação numérica, utilizando o programa Hydrus 1D. As simulações tiveram dois objetivos diferentes: no primeiro foi avaliado os resultados da simulação em comparação à situação atual no campo; no segundo foi avaliada a sensibilidade do transporte em função da alteração dos parâmetros obtidos experimentalmente Ks; Kd; s e (Van Genuchten); e dos parâmetros obtidos na literatura. Os resultados permitiram concluir que o modelo Hydrus 1D consegue representar a contaminação do HCH no solo. O parâmetro de degradação na água foi essencial para chegar em ordens de grandeza de concentrações próximas das identificadas em campo. Os parâmetros de degradação, difusividade, dispersividade e condutividade hidráulica são os que mais afetam os resultados finais de concentração do HCH na água subterrânea e, portanto, merecem atenção maior durante as futuras investigações.
This paper presents the geoenvironmental characterization of soils from a contaminated site, located in Santo André, São Paulo State, Brazil. The objective was to determine experimental parameters to allow the study of some aspects of transport of the organochlorine pesticide hexachlorocyclohexane (HCH). The study site contains trenches with about 30,000 tons of a material containing high concentrations of HCH. The site investigations show that there are HCH concentrations in groundwater. In 2011, disturbed and undisturbed soil samples were collected at four different surface points of the contaminated site, and then a sample of soil from rock alteration layer (SAR) was also composed for characterization in order to answer questions concerning the mobility of contaminant in the site. The environmental characterization based on laboratory tests, was performed by the following analyzes: grain size distribution, Atterberg limits, specific gravity, porosity, moisture content, water retention curve, hydraulic conductivity, pH, electrical conductivity, cation exchange capacity (CEC), organic matter content and volatile content. The surface soil of the area is heterogeneous and the adsorption capacity of the soils analyzed were lower than expected. This characterization allowed the study of flow and transport of HCH through numerical simulation using the Hydrus 1D software. The simulations had two different goals, the first was evaluated the simulation results compared to the current situation in the field. In a second step the sensitivity of transport due to the change of the parameters obtained experimentally Ks; Kd; s and (Van Genuchten); and parameters obtained from the literature. The results showed that the Hydrus 1D model simulates HCH contamination in soil. Water degradation parameter was essential to get orders of magnitude similar to those identified in field concentrations. The degradation, diffusivity, hydraulic conductivity and dispersivity parameters are those that most affect the final results of concentration of HCH in groundwater and therefore deserve more attention in future investigations.

Apesar da pequena influência antrópica direta em seu território, a Antártida não pode ser considerada livre do alcance de poluentes. No presente estudo, avaliou-se a distribuição e transferência de poluentes orgânicos (PCBs, pesticidas organoclorados e PBDEs) em compartimentos abióticos (neve e água de degelo) e bióticos (liquens, musgos, invertebrados, peixes, ovos de aves e tecidos de aves e pinípedes, para os quais também foi aplicada análise isotópica de nitrogênio-15 e carbono-13) do ecossistema da Baía do Almirantado. Os compartimentos abióticos tiveram concentrações entre 1,4 e 156 pg L-1, apenas para grupos de organoclorados, com variação intra-sazonal importante e compatibilidade com níveis tróficos inferiores e amostras de vegetação, que por sua vez refletiram a importância de fontes secundárias de poluentes. Nos animais, grosso modo, os compostos prevalecentes (em ng g-1 peso úmido) foram PCBs, (6,82-1821), HCB (0,060-136) e DDTs, (0,410-524), níveis de duas a três ordens de grandeza superiores aos encontrados em vegetação. PBDEs ocorreram, de modo geral, em níveis uma ou duas ordens de grandeza abaixo dos organoclorados. A análise isotópica mostrou-se útil como ferramenta indicadora de nível trófico e origem de matéria orgânica consumida, correlacionando-se quantitativa e qualitativamente com os poluentes orgânicos pela indicação de fatores como stress nutricional e mudança de área de forrageio e/ou de dieta. Como alternativa, foi proposto um novo indicador de biomagnificação baseado no peso molecular dos PCBs, que apresentou resultados estatisticamente superiores ao ?15N na maioria dos casos.
Despite the small antropic direct influence on its territory, Antarctica cannot be considered out of pollutants\' reach. The present study evaluated the distribution and transfer of organic pollutants (PCBs, organochlorine pesticides and PBDEs) in both abiotic (snow and melting water) and biotic (lichens, mosses, invertebrates, fishes, bird eggs and bird and pinnipeds\' tissues, for which was also applied carbon-13 and nitrogen-15 stable isotopes analyses) compartments of the ecosystem from Admiralty Bay. Abiotic compartments showed concentrations between 1,4 and 156 pg L-1, only for organochlorine groups, with considerable intraseasonal variation and compatibility with lower trophic levels and vegetation samples, which in turn reflected the importance of secondary pollutants sources. In animal samples, grosso modo, the prevailing compounds were (in ng g-1 wet weight) PCBs (6,82-1821), HCB (0,060-136) and DDTs, (0,410-524), levels from two to three orders of magnitude superior to the ones found in vegetations. PBDEs occurred, in a general way, in levels from one to two orders of magnitude lower than the organochlorines. Stable isotope analyses proved useful as an indicator tool for trophic level and consumed organic matter, correlating itself in a qualitative and quantitative way with the organic pollutants by indication of factors as nutritional strees and variation in foraging areas and/or diet. As an alternative, a new biomagnifications indicator based on PCBs molecular weight was proposed, showing results statistically superior to the ?15N in the majority of the cases.

The organochlorine pesticide endosulfan has been shown to be highly toxic to fish and there is some evidence to support that it may act as an endocrine disrupting chemical. Juvenile rainbow trout (Oncorhynchus mykiss) were caged at 4 sites in Oshawa Creek during the fall and spring of 2008 and 2009 while another group was intra-peritoneal injected in the laboratory with varying concentrations (ppm) of endosulfan. Plasma vitellogenin (VTG) levels, liver ethoxyresorufin-O-deethylase (EROD), citrate synthase (CS), lactate dehydrogenase (LDH), and brain acetylcholine esterase (AChE) (caged fish only) enzymatic activities were measured. Trout injected with endosulfan experienced an increase of the anaerobic (LDH activity) and a decrease of the aerobic (CS activity) metabolic pathways, while male VTG levels increased. Since it was a singular injection, VTG results have to be confirmed. Fall caged trout showed increased EROD activity and inhibited AChE activity while those caged in the spring experienced an unexpected exposure to the lampricide 3-Trifluoro-Methyl-4-Nitro-Phenol (TFM) which disrupted metabolic parameters (inhibited CS and increased LDH activity). Both fall and spring caged trout experienced no induction of VTG activity. Further research is needed since the spring exposure was altered due to the unplanned TFM treatment and thus did not represent a valid temporal replicate.

Dans ce travail de thèse, nous avons analysé les résidus des plusieurs contaminants anthropiques dans des prédateurs de la chaîne alimentaire aquatique et des proies de la chaîne terrestre. En effet, la loutre, le grand cormoran et le silure sont prédateurs piscivores au sommet de la chaîne alimentaire, les pesticides organochlorés, les PCBs et les éléments traces métalliques (plomb, cadmium, cuivre et mercure) ont été détectés dans tous les foies de ces prédateurs prélevés dans les bassins de la Loire en France. Les PCBs sont les organochlorés les plus répandus dans les trois espèces, suivi des DDTs. Les valeurs maximales de PCBs ont atteint 1,61, 1,96 et 0,28 mg/kg de poids frais pour les cormorans, les loutres et les silures, respectivement. La concentration du mercure a dépassé la limite toxique pour plus de 40 % des cormorans analysés. L‘effet « cocktail » de ces contaminants sur les trois espèces n‘est pas étudié dans cette thèse. Cependant, Les concentrations des organochlorés et des éléments traces dans ces prédateurs sont généralement modestes ou faibles. Ainsi, Il nous semble que ces contaminants ne constituent pas une menace pour la conservation de ces espèces à court ou moyen terme. Par ailleurs, dans le réseau trophique terrestre, nous avons trouvé que trois rodenticides anticoagulants la chlorophacinone, la bromadiolone et le brodifacoum s‘accumulent dans les limaces de la manière rapide et stable au cours de temps, par contre aucune mortalité n‘a été observée chez les limaces. Le brodifacoum a été détecté dans plus de 90 % des limaces prélevées sur le terrain, et nous avons constaté que ces limaces représentaient un risque élevé d'empoisonnement secondaire pour trois de leurs prédateurs, le hérisson européen, la musaraigne commune et l'étourneau sansonnet. On pourrait donc confirmer que les invertébrés constituent une source non négligeable de rodenticides pour leurs prédateurs.L‘objectif de cette thèse est de montrer l‘influence du régime alimentaire sur la contamination des proies, des prédateurs et d‘évaluer les risques toxicologiques pour ces espèces
In this work, we analyzed the residues of several anthropogenic contaminants in predators of the aquatic food chain and prey of the terrestrial chain. The otter, the great cormorant and the catfish are piscivorous predators at the top of the food chain. Organochlorine pesticides, PCBs and trace elements (lead, cadmium, copper and mercury) were detected in all these predators collected from the basins of the Loire in France. Residue level of PCBs in these predators was the highest followed by DDTs and maximal PCB values reached 1.61, 1.96, and 0.28 mg/kg wet weight for cormorants, otters, and catfish, respectively. The concentration of mercury exceeded the toxic thresholds for more than 40% of the cormorants analyzed. The possible combined effect of these contaminants on the three species has not been studied in this thesis. However, the concentrations of organochlorines and trace elements are generally modest or low. Thus, it seems that these contaminants do not constitute a major threat to the conservation of these species for the short or medium term. Furthermore, in the terrestrial food chain, we found that three anticoagulant rodenticides chlorophacinone, bromadiolone and brodifacoum accumulate in slugs in a stable way over the time, whereas no mortality was observed in slugs. Brodifacoum was detected in more than 90% of the slugs collected in the field, and we found that these slugs represented a high risk of secondary poisoning for three of their predators, European hedgehog, common shrew and European starling. Therefore, it could be confirmed that invertebrates constitute a non-negligible source of rodenticides for their predators.The objective of this thesis is to show the influence of the diet on the contamination of prey, predators and to evaluate the toxicological risks for these species

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.