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Mercury, Dieldrin, DDT, DDE, and PCB Levels in Tissues From Fish and Wildlife, in UtahSmith, Fred A. 01 May 1973 (has links)
Fish and wildlife were randomly sampled in Utah from pre-selected x areas and analyzed for levels of total mercury, dieldrin, DDT, and DDE. Levels were well within consumptive tolerance or guildeline limits except for mercury levels of fish in Willard Bay Reservoir. PCB's were also identified in a large proportion of samples. None of the chukars, 6 percent of the pheasants, 4 percent of the waterfowl, and none of the fish sampled, excluding Willard Bay Reservoir, were above the 0.5 ppm guideline level for mercury established by the Food and Drug Administration. Seventy-seven percent of the fish sampled from Willard Bay Reservoir were above the 0.5 ppm guideline level. Only one duck (2 percent) was above the maximum permissible concentration for dieldrin. All of the chukars, pheasants, other waterfowl, and fish were well below human consumptive tolerance limits for dieldrin and DDT + DDE. It is recommended that studies be initiated to more closely define possible sources of mercury and the health hazard involved in consumption of these fish.
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The Effect of Subsurface Hydrology on DDT Degradation in Soils at Point Pelee National Park, Ontario, CanadaMarenco , Nadia 09 1900 (has links)
<p> Systematic soil sampling and analyses provided DDT, DDE and DDD, organic and mineral matter concentrations, as well as various soil physical and hydraulic properties from three study sites at Point Pelee National Park. A soil's physical properties, soil and water management practices, and DDT application history, can affect DDT degradation and change the relative amount of its metabolites. DDD is the principal product of the dechlorination of DDT in high moisture content, reducing
anaerobic soil environments. The main degradation product in soils under aerobic conditions is DDE. %DDT, %DDE and %DDD abundances used in conjunction with soil environment characterization data, can be used to indicate not only whether DDT is degrading, but what environmental factors are controlling its degradation. At the Park,
DDT is primarily lost from the soil by microbial degradation to DDE and DDD. %DDT, %DDE and %DDD ratios from each study site indicated that wetter more organic-rich soil environments degraded DDT to its metabolites at a faster rate than drier less organicrich soils. Moreover, historical water level data was used to illustrate that this wetter
study site was flooded for part of the year when adjacent marsh water levels were high. These conditions resulted in the accumulation of organic matter over time and the creation of alternating anaerobic/aerobic conditions in the soils resulting in an increased
rate of degradation of DDT in these areas. Based on the relative %DDT in the soils at each study site, relative half-life estimates for the first order decay of DDT to its metabolites DDE and DDD were calculated. Half-life estimates for DDT at the wettest and most organic-rich study site range from 6 to 8 years; significantly lower than the two other study sites, which range from 15 to 30 years and are on the high end of the range reported in the literature.</p> / Thesis / Master of Science (MSc)
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Remediation of DDT Contaminated Soil: A Field StudyBadley , Joanne 07 1900 (has links)
<p> Point Pelee National Park in Leamington, Ontario, Canada contained a large component of private farming and recreation until the 1960's. DDT was applied at the park as pest control in the orchards and recreational areas between 1948 and 1960. Recent studies have shown that the compounds DDT, DDE and DDD are highly persistent in the shallow soils of Point Pelee National Park. A laboratory treatability
experiment has been effective in the removal of DDT, DDE and DDD from columns packed with soil collected from Point Pelee National Park, using hydroxypropyl-ß-cyclodextrin. Cyclodextrins are microbially produced cyclic oligosaccharides which have a unique hydrophilic shell and a hydrophobic cavity. They are able to form inclusion complexes and aid in the transport of relatively insoluble compounds. A pilotscale
field remediation experiment involving the application of hydroxypropyl-ß-cyclodextrin to a Random Latin-Squares design was completed at Point Pelee National Park over the course of five months. Systematic soil sampling and analyses provided DDT, DDE and DDD concentrations throughout the remediation experiment in order to assess the removal efficiency of hydroxypropyl-ß-cyclodextrin. In-Situ volumetric moisture content was monitored throughout the study with a TDR based system.
Systematic soil sampling and analyses at the conclusion of the study provided water content, organic matter content, bulk density, porosity, hydraulic conductivity as well as sampling with depth. The application of a hydroxypropyl-ß-cyclodextrin solution did result in a substantial decrease of the concentrations of DDT, DDE and DDD from the
surface soil at Point Pelee National Park. By the end of the experiment, the concentration of DDD was consistently below the regulatory limits set by the Ontario Ministry of Environment and Energy for Parkland/Recreational Land-Use. In addition to the observed decrease in concentration, there was a decrease in the degree of variation
between the measured concentrations, transport of the mass of DDT, DDE and DDD to depth and an observed tailing effect at late-times. There were also fundamental changes to the system due to the application of the cyclodextrin (HPCD) solution including an increase in moisture content and organic matter, a decrease in infiltration and a
corresponding decrease in field saturated hydraulic conductivity. There was no appreciable benefit of the application of a high concentration solution over a low concentration solution due to an observed "clogging" -effect. The results of this study indicates that further research is necessary to determine the extent of vertical mobilization
of DDT, DDE and DDD to groundwater and the role of biological matter in the observed fundamental changes responsible for the "clogging" -effect.</p> / Thesis / Master of Science (MSc)
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Polygenic Resistance In The Highly DDT-resistant 91-r Strain Of Drosophila Melanogaster Involves Decreased Penetration, Increased Metabolism And Direct Excretion Of DdtStrycharz, Joseph P 01 January 2010 (has links) (PDF)
Resistance to dichlorodiphenyltrichloroethane (DDT) in the 91-R strain of Drosophila melanogaster is extremely high compared to the susceptible Canton-S strain (>1500 times). Oxidative detoxification is involved in resistance but is not the only mechanism. Rates of DDT penetration, metabolism, and excretion were determined radiometrically between resistant 91-R and susceptible Canton-S strains. Contact penetration was ~1.5-times slower with 91-R flies compared to Canton-S flies. The 91-R strain had 13-fold more cuticular hydrocarbons, possibly resulting in penetration differences. DDT was metabolized ~33-fold more extensively by 91-R than Canton-S resulting in dichlorodiphenyldichloroethane (DDD), two unidentified metabolites and polar conjugates being formed in significantly greater amounts. 91-R also excreted ~5.0 times more DDT and metabolites than Canton-S. Verapamil pretreatment reduced the LD50 value for 91-R flies topically dosed with DDT by a factor of 10-fold. Thus, it is likely that the increased excretion by 91-R flies is due to the increased expression of ATP-binding cassette (ABC) transporter genes, including MDR50 (CG8525) that had a 36% higher transcript level by quantitative real time PCR than Canton-S flies. In summary, DDT resistance in 91-R is polyfactorial and includes reduced penetration, increased detoxification and direct excretion.
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The Early Propagation And Burning Of Hydrogen In The Process Of The Deflagration To Detonation TransitionAmasay, Rom 01 January 2022 (has links)
The safe and efficient propagation of the Deflagration to Detonation Transition (DDT) is a topic that has been researched for many years due to its applications in Aerospace and Mechanical Engineering. DDT is when fire caused by the burning of fuel is accelerated to the upper CJ point on the Rankine Hugoniot curve due to instabilities in the flame and the turbulence caused by these instabilities. The complex flame dynamics that go along with DDT have ensured that the process is yet to be fully understood and defined. This research will work towards observing the early stages of burning hydrogen-air mixtures in DDT conditions in order to better understand the processes that cause DDT. The research will also involve the testing of multiple different equivalence ratios of hydrogen known to undergo DDT. This research will assist in making places that store reactive gasses such as hydrogen safer by searching for the method of DDT formation and ways to prevent it. This research will also allow for safer commercial use of DDT in Detonation Based Engines. The research was tested in a secure facility and observed the first four inches of ignition and deflagration using schlieren and chemiluminescence imaging techniques. Through the research, it was found that flames at higher equivalence ratios tend to be longer, more top-biased, and have more instabilities than flames of lower equivalence ratios, better preparing them for DDT. This study will be elaborated on in future research using a variety of different fuels to solidify the findings of the research performed and to assist in the ability to innovate using DDT.
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Blood characteristics as predictors of reproductive success in quail species exposed to DDTSullivan, Joseph P. 26 February 2007 (has links)
Present sampling techniques are not capable of assessing both contamination with an organochlorine chemical and reproductive success without the need for removing individuals from that population. Experiments were performed to evaluate vitellogenin, vitamin A, and vitamin E as biomarkers of contamination with DDT, an organochlorine pesticide, and reproductive success in Japanese quail (Coturnix coturnix japonica) or northern bobwhites (Colinus virginianus).
The utility of vitellogenin as a biomarker in northern bobwhites was investigated. Female northern bobwhites were dosed with 0, 1, 10, or 100 μg DDT/g body weight via corn oil intubation. The females were induced to lay eggs by providing the proper daylength, and number of eggs laid was monitored. No differences were found for number of eggs laid, egg morphology, or plasma concentration of vitellogenin among dose groups.
Dietary supplementation and corn oil intubation were evaluated as alternative dosing techniques because handling involved with intubation may have caused decreased egg production in all treatment groups in the first experiment. Nonlaying female bobwhites were dosed with 0 μg DDT, 25 μg DDT/g food, or 25 μg/g body weight (intubation). Bobwhites receiving DDT via intubation accumulated more DDT in brains and livers than did bobwhites receiving DDT via their diet. The two techniques were found not to be equivalent.
Vitamins A and E were investigated as biomarkers of DDT contamination and reproductive success in Japanese quail. Female Japanese quail were given 0, 1, 10, or 25 μg dietary DDT. Significant differences were found among dose groups for reproductive success (number of eggs showing embryonic development), and for plasma concentrations of vitamin A. Concentrations of vitamin E were not measurable. Correlation and regression analyses failed to show a relationship between reproduction and vitamin A concentrations.
Vitamins A and E also were investigated as biomarkers in northern bobwhites. Female bobwhites were given 0, 1, 10, or 25 ppm dietary DDT. No significant differences were found among dose groups for reproductive success or for concentrations of either vitamin A or vitamin E. Correlation and regression analyses again failed to show any relationship between reproduction and plasma concentrations of vitamins A or E.
During each experiment, concentrations of DDT and its metabolites were measured. DDE/DDT ratios in livers, a means of estimating liver enzyme induction, were calculated. The DDE/DDT ratios in livers of Japanese quail and northern bobwhites were found to be markedly different. More work needs to be done to better evaluate the relationship between differences in enzyme induction and reproductive success among different species. / Ph. D.
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Relation of the sex chromosome to DDT resistance in the German cockroachCochran, Donald G. 21 July 2009 (has links)
1. Reciprocal crosses were made between a DDT-resistant and a nonresistant strain of the German cockroach.
2. The techniques employed in rearing the roaches and obtaining toxicological data on the different strains, as well as the genetical and statistical procedures, are described.
3. The toxicological data are presented in the form of regression lines with appropriate statistical analyses.
4. A table showing the relative resistance to DDT of the various strains involved in this study is included.
5. Several conclusions are drawn relative to the inheritance of resistance to DDF in the German cockroach. / Master of Science
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Adsorption statique de PCB et de DDT sur charbons actifs en milieux aqueux / Static adsorption of PCBs and DDT onto activated carbons in aqueous phasesTran, Van Nam 19 December 2012 (has links)
L’adsorption solide-liquide des PCB et des DDT constitue un moyen efficace pour leur récupération des eaux polluées à condition d’avoir une meilleure connaissance du mécanisme impliqué. Les cinétiques d’adsorption statique ont été principalement réalisées à 25 °C avec le2-PCB, un mélange de tétra-, penta- et hexa-CB et le 4,4’-DDT sur 3 charbons actifs (CA) en poudre différents par le précurseur (houille, bois) et le mode d’activation (H2O, H3PO4) dans l’eau, en présence ou non d’éthanol. Les résultats marquants ont été les suivants : L’adsorption du polluant sur le CA est d’autant plus favorisée que sa solubilité dans la phase liquide est plus faible. Ainsi, l’adsorption du polluant hydrophobe est très augmentée dans l’eau pure. L’adsorption des polluants favorisée par la microporosité développée est essentiellement un phénomène de surface où interviennent les forces de Van der Waals. Une bonne adéquation entre la taille des molécules et la largeur moyenne des pores en forme de fentes montre un confinement maximum des molécules dans la microporosité. L’interaction π−π entre adsorbat et adsorbant, favorisée par le nombre de Cl n’est pas à exclure. Enfin, nous avons montré par la cinétique dans les conditions initiales que l’adsorption y est limitée par le transfert de masse externe. Les modélisations par diffusion superficielle homogène (HSDM), conduisant aux coefficients de diffusion superficielle interne, ont montré que la cinétiqued’adsorption est presque complètement gouvernée par la diffusion intraparticulaire. / The solid-liquid adsorption of PCBs and DDT is an effective process for the recuperation of wastewaters but a better understanding of the involved mechanism is required. In this study, the static adsorption kinetics were mainly carried out at 25 ° C for 2-PCB, a mixture of tetra-, penta-and hexa-CB, and 4,4 '-DDT onto three different powdered activated carbons (AC) of the precursor (coal, wood) and the activation mode (H2O, H3PO4) in water, with or without ethanol. The prominent results were as follows: The adsorption of the pollutant on the AC is favored if its solubility in the liquid phase is lower. As a result, the adsorption of the hydrophobic pollutant is significantly increased in pure water. Moreover, the adsorption of pollutants favored by the developed microporosity is a surface phenomenon which involved the Van der Waals forces. A good fit between the size of molecules and the average width of the slit-shape pores gave a maximum confinement of molecules in the micropores. The π−π interaction between adsorbate and adsorbent, favored by the number of Cl, is not excluded. Finally, by studying the kinetics of the initial conditions, we found that the adsorption is limited by the external mass transfer. The internal surface diffusion coefficients estimated from applying the homogeneous surface diffusion models (HSDM) showed that the adsorption kinetics are almost completely governed by the intra-particle diffusion.
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Exposição a substâncias organocloradas em São Paulo: níveis séricos em doadores de sangue e fatores associados / Exposure to organochlorine substances in São Paulo: serum levels in blood donors and associated factorsNascimento, Felipe Parra do 01 April 2016 (has links)
A utilização de pesticidas organoclorados é motivo de preocupação das entidades ligadas à área de saúde em todo o mundo. Apesar de as formas de contaminação serem bem conhecidas, não há um controle eficaz na fiscalização do seu uso no Brasil. Sabe-se que altos níveis séricos destes compostos nos organismos de seres humanos e animais acarretam sérios problemas de saúde. Tendo em vista essa realidade, foi realizado, em 2009, o Projeto Piloto do I Inquérito Nacional de Populações Expostas a Substâncias Químicas, cujo subprojeto \"doadores de sangue\" teve como objetivo mensurar as concentrações de substâncias químicas no sangue de 547 residentes da região metropolitana de São Paulo, dentre elas os pesticidas organoclorados. Este trabalho teve como objetivos avaliar as concentrações dos pesticidas hexaclorobenzeno (HCB), alfa-HCH, ?-HCH, beta-HCH, beta-HCH, heptacloro, heptacloro epóxido, dieldrin, mirex, o,p\'-DDT, p,p\'-DDT, o,p\'-DDE, p,p\'-DDE, o,p\'-DDD e p,p\'-DDD nesta população e compará-las com as encontradas em outros países e determinar fatores associados aos níveis mais elevados destas substâncias. O método analítico utilizado foi de cromatografia a gás. Os resultados deste estudo indicam que a população adulta de São Paulo não está exposta a níveis preocupantes de pesticidas organoclorados, pois dentre os compostos analisados, apenas o beta-HCH e o p,p\'-DDE tiveram um número significante de amostras acima do limite de quantificação, 10,7% e 31,2% das amostras respectivamente. Quando utilizada a metade do limite de quantificação para substituir os valores abaixo do limite de quantificação do método, o valor médio encontrado para o beta-HCH foi de 0,028 ug/dL e para o p,p\'-DDE foi de 0,045 ug/dL. Este estudo propôs dois modelos multivariados para explicar os fatores associados aos compostos beta-HCH e p,p\'-DDE no sangue dos doadores. Segundo o modelo de Regressão Logística Ordinal Multivariado, os fatores associados a níveis mais altos de beta-HCH foram ter idade entre 26 e 45 anos e ser do sexo feminino. Para o p,p\'-DDE os fatores associados a níveis mais altos foram ter idade entre 26 e 45 anos, ser do sexo feminino e ter trabalhado com pesticidas, enquanto receber renda mensal de 3 a 5 salários mínimos e consumir derivados de origem animal uma ou mais vezes por semana foram associados a níveis mais baixos de p,p\'-DDE. Segundo o modelo de Regressão Linear Múltipla, os fatores associados a níveis mais altos de beta-HCH foram o sexo feminino, ter contato prévio com pesticidas na região agrícola, ter trabalhado com pesticidas em campanhas de saúde pública, ter trabalhado em empresas de capacitores ou transformadores, ter trabalhado em indústrias de solventes clorados, ter renda mensal de 3 a 5 salários mínimos, consumo de carnes uma ou duas vezes por semana e consumo de frutos do mar uma ou duas vezes por semana, enquanto consumo frequente de cerveja e ter renda mensal de 1 a 3 salários mínimos foram associado a níveis menores de beta-HCH. Já para o p,p\'-DDE, os fatores associados a níveis mais elevados foram ser do sexo feminino, ser não branco, ter trabalhado com pesticidas e consumir água de fontes que não sejam minerais ou de rede, enquanto o consumo frequente de bebidas alcoólicas foi associado a níveis mais baixos de p,p\'-DDE / The use of organochlorine pesticides is a cause of concern to the entities of the health field worldwide. Although the ways of contamination are well known, there is no effective surveillance of its use on Brazil. It\'s known that high levels of these compounds on human beings and animals entails serious health problems. Foreseeing this reality, a Pilot study of the 1st National Inquiry of Populations Exposed to Chemical Compounds was carried out in 2009, in a subproject called \"blood donors\" had the objective to measure the concentrations of chemical compounds on serum from 547 residents of the metropolitan area of São Paulo, among them, the organochlorine pesticides. This study had as objectives to evaluate the levels of the pesticides hexachlorobenzene (HCB), alfa-HCH, beta-HCH, beta-HCH, beta-HCH, heptachlor, heptachlor epoxide, dieldrin, mirex, o,p\'-DDT, p,p\'-DDT, o,p\'-DDE, p,p\'-DDE, o,p\'-DDD e p,p\'-DDD on blood donors and compare these with the ones found on other countries and to find out factors associated with higher levels of those compounds in the population. The analytical method used was gas chromatography. The results of this study indicate that, overall, the population in São Paulo is not exposed to high levels of these compounds because of all compounds analyzed, only beta-HCH and p,p\'-DDE had a significative number of samples above the quantification limit, 10,7% and 31,2% of the samples respectively. Using the half of the quantification limit to substitute the values below the quantification limit, the beta-HCH mean level was 0.028 ug/dL and p,p\'-DDE mean level was 0.045 ug/dL. This study proposed two multivariate models to explain the factors associated with beta-HCH and p,p\'-DDE blood levels. According to the Multivariable Ordinal Logistic Regression model, the factors associated with higher levels of beta-HCH were age between 26 and 45 years and female gender. For the p,p\'-DDE, the associated factors with higher levels were age between 26 to 45 years, female gender and previous work with pesticides while having income of 3 to 5 minimum wages and consumption of derivates of animal origin at least once per week were associated to lower levels of p,p\'-DDE. According to the Multiple Linear Regression model, the factors associated with higher levels of beta-HCH were female gender, previous contact with pesticides on agricultural region, working with pesticides on campaigns of public health, in companies of capacitators or transformers, in companies of chlorinated solvents, having income of 3 to 5 minimum wages, consumption of meat once or twice per week, and consumption of seafood once or twice per week, while frequent consumption of beer and income of 1 to 3 minimum wages lead to lower levels of beta-HCH. Factors associated with higher levels of p,p\'-DDE were female gender, being non-white, previous work with pesticides and consumption of water from sources that not mineral or mains, while frequent consumption of alcohol were associated with lower levels of p,p\'-DDE
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Acumulação de compostos organoclorados (PCBs, DDTs e HCB) em tecido hepático de delfinídeos (Cetacea, Mammalia) do Estado do Rio de Janeiro / Organochlorine compounds accumulation (PCBs, DDTs and HCB) in hepatic tissue of delphinids (Cetacea, Mammalia) from Rio de Janeiro StateLeticiaà Nadine Alves Legat 25 February 2011 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / No decorrer das últimas décadas a pesquisa relacionada à contaminação de organismos marinhos por compostos organoclorados (OCs) se intensificou aliada à utilização de algumas espécies como sentinelas da qualidade ambiental quanto aos poluentes orgânicos. Dentre essas espécies, podem-se destacar os cetáceos, animais que entre outras características possuem grande longevidade, alta porcentagem lipídica em seus tecidos e são predadores de topo de cadeia trófica, tendendo assim a acumular altos níveis de OCs em seus tecidos. O presente estudo teve por objetivo determinar as concentrações de OCs de origem industrial e agrícola (PCBs, HCB e DDTs) em tecido hepático de oito diferentes espécies de cetáceos delfinídeos pertencentes a três distintas áreas oceânicas do Estado do Rio de Janeiro, são elas a região costeira, a plataforma continental e a região oceânica. A determinação foi realizada em cromatógrafo a gás (GC - Agilent 6890) conectado a um espectrômetro de massa (MS - Agilent 5973). Os valores de DDTs (1263617272 ng.g -1 lip.) e PCBs (7648877288 ng.g -1 lip.) aqui encontrados estão entre os mais altos já reportados para o táxon. Em todas as áreas observou-se uma predominância do ΣPCB, seguida do ΣDDT e HCB, em níveis que refletem o caráter fortemente industrial da região analisada. Entre os PCBs, a maior contribuição advém dos hexabifenis, seguida dos hepta e pentabifenis, sendo os congêneres 153, 138 e 180 os principais em todas as áreas. A razão p,pDDE/ΣDp,pDDT foi alta em todas as regiões (0,9), refletindo um input antigo do poluente na área. Foram realizadas correlações entre as concentrações de OCs e os parâmetros biológicos das espécies, como idade, sexo e comprimento total. A transferência placentária de OCs foi analisada em dois pares de fêmea-feto de Sotalia guianensis, mostrando uma maior transferência dos compostos com menor log Kow. Como esperado, foi encontrada uma diferença significativa no perfil de contaminação entre as espécies das diferentes regiões, relacionada à proximidade da fonte, características espécie-específicas e ao arranjo trófico das espécies. / Over the past decades the research on marine organisms contamination by organochlorine compounds (OCs) has been intensified, allied to the utilization of some species as sentinels of the environmental quality related to organic pollutants. Among these species, cetaceans stand out as animals that, between other characteristics, have great longevity, high lipid percentage on their tissues and are top predators in food chains, therefore having the tendency to accumulate high OCs levels in their tissues. The present study aimed to determine OCs concentrations from industrial and agricultural sources (PCBs, HCB and DDTs) in hepatic tissue of eight different species of delphinid cetaceans belonging to three different oceanic areas of Rio de Janeiro State, namely, coastal region, continental shelf and oceanic region. The determination was performed in an Agilent 6890 gas chromatograph (GC) connected to an Agilent 5973 mass spectrometer (MS). DDTs (1263617272 ng.g -1 lip.) and PCBs (7648877288 ng.g -1 lip.) values reported here are amongst the highest values ever reported for the taxon. In all areas ΣPCB predominance was observed, followed by ΣDDT and HCB in levels that reflect the highly industrial character of the analyzed region. Amongst PCBs, the largest contribution comes from hexa biphenyls, followed by hepta and penta biphenyls, being the 153, 138 and 180 the main congeners in all areas. The p,pDDE/ΣDp,pDDT ratio was high in all regions (0,9), reflecting an ancient input of the pollutant in the area. Correlations between OCs concentrations and biologic parameters such as age, sex and total body lenght were performed. OCs placental transfer was analyzed in two Sotalia guianensis mother-fetus pairs, showing a higher transfer of compounds with lower log Kow. As expected, a significant difference was found on the contamination profile between species from the different regions, related to source proximity, species-specific characteristics and the species trophic arrangement.
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