L'atmosphère terrestre est le siège d'un transport de matière, en particulier d'éléments d'origines diverses, dont une proportion importante résulte des activités humaines. Ce phénomène induit des conséquences parfois graves, pour la santé humaine et pour la fonctionnalité des écosystèmes. Les éléments ainsi transférés sont redéposés, de manière complexe, à la surface de la terre, avec une cartographie de distribution très inégale, des possibilités d'accumulation, ou au contraire de dilution, variables, conduisant à des altérations diversifiées de la composition des eaux et des sols et de la fonctionnalité des êtres vivants. La redéposition atmosphérique est étudiée depuis une cinquantaine d'année sur les troncs des arbres, qui constituent une matrice verticale commune, très enrichie par l'apport atmosphérique, et pouvant mener soit à une analyse de composition, soit à des études de bioindication. Il en a découlé des tests de routine largement utilisés. Cependant, pour définir avec précision les apports d'origine anthropique et mieux maîtriser, en vue de les réduire, les apports anormaux ou dangereux, une étude en profondeur de cette déposition corticale devait être entreprise. C'est l'objet de ce mémoire. Au regard de la complexité du problème abordé, nous nous sommes essentiellement limité à l'étude d'une seule espèce d'arbre : Fraxinus excelsior L., très commun dans notre zone d'étude et couvrant une vaste échelle d'altitude. Notre démarche analytique a consisté à combiner une analyse élémentaire très complète et sensible, l'ICP-MS avec une observation en microscopie à balayage couplée à la détermination de l'émission de rayons X spécifique des éléments présents. Cet ensemble de deux méthodes a permis de combiner identification - dosage précis - localisation - distinction entre états particulaire et dispersé. La déposition atmosphérique a été considérée sur une échelle de temps allant de 3 mois à 40 ans, en séparant les pousses successives des arbres. Nous avons séparé le dépôt superficiel sur les surfaces végétales d'une fraction solidement intégrée dans les tissus des tiges, spécialement le suber. Ces deux entités ne correspondent pas à la même chronologie. Nous avons montré que le dépôt de surface était, de fait, un écosystème construit sur un biotope alimenté conjointement par l'atmosphère et par l'arbre lui-même et qu'il comportait une phase vivante reviviscente et pour partie photosynthétique. Ce dépôt superficiel est déplacé en grande partie par la pluie. Le suber, couche apoplastique imperméable, a une bonne capacité de rétention des éléments à long terme et constitue, comparativement aux autres tissus des tiges, une matrice très intéressante pour percevoir l'apport atmosphérique sur plusieurs décennies. Pour déterminer valablement les apports atmosphériques d'origine anthropique qui s'accumulaient dans ces deux types de matrices, nous avons conçu un système de calcul (AAEF) permettant de les séparer des apports géogéniques et biologiques. Par ailleurs, constatant que l'apport atmosphérique comportait deux types de constituants, soit dispersés, soit particulaires, nous avons conçu et mis en oeuvre un protocole de fractionnement basé 1) sur l'incinération, 2) sur les traitements successifs à l'eau et à l'acide nitrique concentré (2N) qui nous a permis d'étudier isolément une phase particulaire dans laquelle la masse des matériaux géogéniques se trouve rassemblée avec l'essentiel du plomb et du manganèse, la phase HNO3 concentrant les éléments comme le cuivre et le zinc et une phase H2O contenant l'essentiel du potassium. Les profils de distribution entre les différentes fractions semblent constituer une information intéressante sur la spéciation de plusieurs types d'éléments. L'ensemble du corpus méthodologique ainsi édifié permet d'accéder à des études assez réalistes d'historique et de distribution géographique des polluants élémentaires à des échelles de distances variées.

Radionuclides are widely used in energy production and medical, military and industrial applications. Thus, understanding the behaviour of radionuclides which have been or may be released into ecosystems is important for human and environmental risk assessment. Modelling of radionuclides or their stable element analogues is the only tool that can predict the consequences of accidental release. In this thesis, two dynamic stochastic compartment models for radionuclide/element transfer in a marine coastal ecosystem and a freshwater lake were developed and implemented (Paper I and III), in order to model a hypothetical future release of multiple radionuclides from a nuclear waste disposal site. Element-specific mechanisms such as element uptake via diet and adsorption of elements to organic surfaces were connected to ecosystem carbon models. Element transport in two specific coastal and lake ecosystems were simulated for 26 and 13 elements, respectively (Papers I and III). Using the models, the concentration ratios (CR: the ratio of the element or radionuclide concentration in an organism to the concentration in water) were estimated for different groups of aquatic organisms. The coastal model was also compared with a 3D hydrodynamic spatial model (Paper II) for Cs, Ni and Th, and estimated confidence limits for their modelled CRs. In the absence of site-specific CR data, being able to estimate a range of CR values with such models is an alternative to relying on literature CR values that are not always relevant to the site of interest. Water chemistry was also found to influence uptake of contaminants by aquatic organisms. Empirical inverse relationships were derived between CRs of fish for stable Sr (CRSr) and Cs (CRCs) and water concentrations of their biochemical analogues Ca and K, respectively (Paper IV), illustrating how such relationships could be used in the prediction of more site-specific CRCs and CRSr in fish simply from water chemistry measurements. / <p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: Manuscript. Paper 4: Manuscript.</p>

L’explosion de la nanotechnologie a permis l’intégration d’une multitude de nanoparticules dans des produits de consommation. Les nanoparticules d’argent (nAg) sont les plus utilisées à ces fins, selon les derniers recensements disponibles. La plupart des études toxicologiques, à ce jour, ont fait état de l’implication très évidente de l’ion Ag+ dans la toxicité aigüe des nAg; cependant, quelques études ont mis en évidence des effets toxicologiques dus aux nAg. Il y a un certain consensus à propos d’un risque de contamination des eaux douces via leur rejet par les effluents des réseaux d’aqueducs. Puisque les concentrations en Ag+ sont généralement très faibles dans les eaux douces (de l’ordre du pg L-1), de par la formation de complexes non-labiles avec des thiols (organiques et inorganiques) et des sulfures, la toxicité inhérente aux nAg pourrait ne pas être négligeable- comparativement aux tests en laboratoires. Cette étude s’intéressait donc aux mécanismes de bioaccumulation d’argent par l’algue verte C. reinhardtii suite à l’exposition à des nAg de 5 nm (enrobage d’acide polyacrylique). La bioaccumulation d’argent pour l’exposition à Ag+ servait de point de comparaison; également, les abondances de l’ARNm de l’isocitrate lyase 1 (ICL1) et de l’ARNm de Copper Transporter 2 (CTR2) étaient mesurées comme témoins biologiques de la bioaccumulation de Ag+. Les expériences ont été menées en présence d’un tampon organique (NaHEPES, 2 x 10-2 M; Ca2+, 5x 10-5 M) à pH de 7,00. Pour des expositions à temps fixe de 2 heures, la bioaccumulation d’argent pour nAg était supérieure à ce qui était prédit par sa concentration initiale en Ag+; cependant, il n’y avait pas de différence d’abondance des ARNm de ICL1 et de CTR2 entre nAg et Ag+. D’un autre côté, pour une exposition à temps variables, la bioaccumulation d’argent pour nAg était supérieure à ce qui était prédit par sa concentration initiale en Ag+ et une augmentation de l’abondance de l’ARNm de ICL1 était notée pour nAg. Cependant, il n’y avait aucune différence significative au niveau de l’abondance de l’ARNm de CTR2 entre nAg et une solution équivalente en Ag+. L’ajout d’un fort ligand organique (L-Cystéine; log K= 11,5) à une solution de nAg en diminuait radicalement la bioaccumulation d’argent par rapport à nAg-sans ajout de ligand. Par contre, l’abondance des ARNm de ICL1 et de CTR2 étaient stimulées significativement par rapport à une solution contrôle non-exposée à nAg, ni à Ag+. Les résultats suggéraient fortement que les nAg généraient des ions Ag+ au contact de C. reinhardtii. / The recent developments in nanotechnology have given rise to a new and increasing economical market where nanoparticles are at the forefront. Recent inventories of the nanoparticles-containing products have shown that silver nanoparticle- containing products are the most frequently used consumer nanomaterial. Due to the fear of a large scale contamination-and even pollution- of the aquatic environment from silver nanoparticles (nAg), studies have been conducted to assess their toxicities, which, in many cases, have been found to be mediated by the concomitant presence of Ag+. Notably, few studies have found evidence of toxicity due to the nAg, per se. Since numerous non-labile complexes are formed with Ag+ in freshwaters- especially with thiols and sulfides-, nAg toxicity might be more relevant in comparison to laboratory tests where the Ag+ tends to dominate toxicity studies. Therefore, this study investigated the mechanisms underlying silver bioaccumulation by the green alga, C. reinhardtii upon exposure to solutions of nAg (nominal size of 5 nm; poly-acrylate coating). Silver bioaccumulation upon exposures to the free ion alone served for comparison. In parallel, the abundance of two mRNAs- ICL1 and CTR2- were used to better understand the mechanisms underlying the bioaccumulation of Ag+ (and potentially nAg). The experiments were conducted in pH buffered solutions (NaHEPES, 2 x 10-2 M; Ca2+, 5x 10-5 M) at pH 7.00. For 2-hour exposures, the silver bioaccumulation for solutions of nAg exceeded what was expected from their Ag+ content only; however, no differences were noticed in the abundance of the expression of ICL1 and CTR2. For variable time exposures, the silver bioaccumulation for solutions of nAg exceeded what was expected from their Ag+ content only. Moreover, the expression of ICL1 was significantly higher for nAg than what was expected based upon an exposure to Ag+ only. When exposed to nAg, expression levels of CTR2 could be predicted from levels based solely on the Ag+ concentrations. The addition of a large excess of L-Cysteine, which is a very strong silver ligand (log K =11.5), to a nAg solution largely decreased silver bioaccumulation, however, bioaccumulation remained significant and the expression of both ICL1 and CTR2 were significantly higher than that of the control solutions (without Ag+). The results strongly suggest that nAg generated Ag+ ions when in contact with C. reinhardtii and that the nAg released to freshwaters might exert its toxicity through organism-contact-dependant release of Ag+.

Made available in DSpace on 2016-08-10T10:44:20Z (GMT). No. of bitstreams: 1 ROSENI DA SILVA SOUZA.pdf: 1686885 bytes, checksum: 0659d802253a7b64e281c9a3cd03a25e (MD5) Previous issue date: 2012-12-10 / This study aimed to assess the level of concentration of toxic metals in water (Cd, Cu, Mn, Pb and Zn) and fish (Al, Fe, Mn, Pb and Zn) from ten sub-basins of the Upper Tocantins River, Goiás State, Central Brazil, from July to August 2008. Each section of the watercourse chosen (50, 500 and 1000m for streams, creeks and rivers, respectively) were georeferenced and demarcated. In these section were sampled water and fish. The water was collected manually at the beginning and end of each section at 50 cm from the surface, then filtered, packaged in bottles and stored at 4 °C. Samples of whole fish or muscle pieces were defrosted, lyophilized, digested and stored in polyethylene bottles previously washed. The determination of the concentration of toxic metals from water samples was performed using the technique of optical emission spectrometry with inductively coupled plasma (ICPOES), and this fish was made using the technique of atomic absorption spectrometry method (flame-AAS). After determination of toxic metals in fish muscles, these were classified by trophic guild (omnivorous, invertivorous, detritivorous, piscivorous, insectivorous and herbivorous) through available literature. The Kruskal-Wallis analysis showed no significant differences between the concentrations of toxic metals in water between sub-basins. The comparison of the concentrations of toxic metals present in fish sampled indicated that there were significant differences between the trophic guilds considered for Al (p = 0.0057), Fe (p = 0.0000), Mn (p = 0.0000 ), Pb (p = 0.0001) and Zn (p = 0.0001). The detritivorous had higher concentration of Fe compared to omnivores, and higher concentrations of Al, Fe, Mn, Pb and Zn in relation to invertivores. The invertivores showed a higher concentration of Mn, Pb, Zn than omnivores. The insectivores have excelled in the concentration of Mn in relation to invertivores and Pb in relation to detritivores. In the case of piscivorous the highest concentration was of Fe and Mn in relation to Mn and detritivorous in relation to omnivores. The correlation analysis between the concentrations of Mn, Pb and Zn indicate that there is no correlation between the water and the fish, whereas positive correlations were observed between the concentrations of Pb and Mn (r = 0. 682834); Zn and Mn (r = 0.716368) and Zn and Pb (r = 0.770089) in sampled fish. It is concluded that the water did not influence directly the contamination of fish by toxic metals, but fish seem to have been contaminated by food, expressed in this study by the trophic guilds. / Este trabalho teve como objetivo avaliar o nível de concentração de metais tóxicos na água (Cd, Cu, Mn, Pb e Zn) e em peixes (Al, Fe, Mn, Pb e Zn) pertencentes a dez sub-bacias do alto rio Tocantins, Goiás, Brasil Central, no período de julho a agosto de 2008. Cada trecho do curso de água escolhido (50, 500 e 1000m para córregos, ribeirões e rios, respectivamente) foi georreferenciado e demarcado. Nesses trechos foram realizadas as coletas de água e peixes. A água foi coletada manualmente no início e no final de cada trecho a 50 cm da superfície, em seguida foi filtrada, acondicionada em frascos e armazenada a 4°C. As amostras de peixes inteiros ou pedaços de músculo foram descongelados e deixados em repouso até atingirem a temperatura ambiente, em seguida foram liofilizados e posteriormente digeridos e estocados em frascos de polietileno previamente lavados. A determinação da concentração dos metais tóxicos das amostras de água foi feita por meio da técnica de espectrometria de emissão óptica com plasma indutivamente acoplado (ICP-OES), e esta dos peixes foi feito por meio da técnica de espectrometria de absorção atômica modalidade chama (EAA-chama). Após a determinação dos metais tóxicos nos peixes, estes foram classificados por guilda trófica (onívoro, invertívoro, detritívoro, piscívoro, insetívoro e herbívoro) através da literatura. A análise de Kruskal-Wallis indicou que não houve diferenças significativas entre as concentrações de metais tóxicos na água entre as sub-bacias. Já na comparação das concentrações de metais tóxicos existentes nos peixes amostrados verificou-se que houve diferenças significativas entre as guildas tróficas consideradas para Al (p=0,0057); Fe (p= 0,0000); Mn (p=0,0000); Pb (p=0,0001) e Zn (p=0,0001). A guilda dos detritívoros tiveram maior concentração de Fe em relação aos onívoros; e maior concentração de Al, Fe, Mn, Pb e Zn em relação aos invertívoros. Os invertívoros apresentou uma maior concentração de Mn, Pb, Zn que os onívoros. Os insetívoros se destacaram na concentração de Mn em relação aos invertívoros e de Pb em relação aos detritívoros. No caso dos piscívoros a maior concentração foi de Fe e Mn em relação aos detritívoros e Mn em relação aos onívoros. A análise de correlação entre as concentrações dos metais tóxicos Mn, Pb e Zn indicam que não há correlação entre as concentrações dos três metais na água com os peixes, enquanto que são observadas correlações positivas significativas entre as concentrações de Pb e Mn (r=0,682834); Zn e Mn (r=0,716368) e Zn e Pb (r=0,770089) entre os peixes. Neste estudo conclui-se que a água não influenciou diretamente na contaminação dos peixes, os quais parecem terem sido contaminados via alimentação, expressa neste estudo pelas guildas tróficas.

Introdução: Estudos experimentais e epidemiológicos têm evidenciado diversos eventos mórbidos associados à poluição do ar, destacando os efeitos na gestação. A utilização de bioindicadores mostra os impactos da poluição em seres vivos, inclusive na espécie vegetal Tradescantia pallida. Objetivos: O presente estudo avaliou efeito da exposição gestacional à poluição do ar no peso ao nascer e a resposta à mesma exposição do bioindicador Tradescantia pallida. As possíveis associações entre as variáveis de exposição (NO2, MP2,5 acúmulo foliar de elementos-traço e proximidade residencial das vias de tráfego veicular) e as variáveis de efeito (resposta mutagênica em T. pallida e peso ao nascer) também foram investigadas. Metodologia: A coorte foi composta por 39 gestantes moradoras do distrito do Butantã, São Paulo, SP. Os domicílios, hábitos dos moradores e morbidade referida foram caracterizados pela aplicação de questionário. Durante 18 meses foram feitas coletas mensais de inflorescências e folhas de T. pallida. Foram utilizados os testes de quantificação de micronúcleos em tétrades de Tradescantia (Trad-MCN) e análise do acúmulo foliar de elementos-traço por EDXRF. Também foram medidos os níveis de NO2, O3 e MP2,5 nas residências, além de medidas individuais em cada gestante. A análise epidemiológica foi composta por análises de regressão linear univariada e múltipla tendo como variável dependente o peso ao nascer. Os dados de exposição e efeito foram georreferenciados e cartograficamente representados utilizando-se as técnicas corocromática e isarítmica, usando como base as residências das gestantes e a proximidade às vias de tráfego veicular, sendo representadas em mapas de isolinhas sobre a base de arruamentos da região. Resultados: Pelo modelo de regressão linear múltiplo, houve uma perda no peso ao nascer de 318,92g (IC 95% -578,44; -59,4) para o intervalo interquartil (20,02?g/m3) referente à exposição ao NO2 indoor no terceiro trimestre gestacional. Esse resultado mostra o impacto da exposição ao NO2 no peso ao nascer, mesmo avaliando outras variáveis de risco para esse desfecho gestacional. Houve uma associação entre o aumento do valor percentual médio de micronúcleos com a diminuição de 49,04g no peso ao nascer (IC 95% = -121,83; 23,75). Os maiores valores percentuais de micronúcleos medidos coincidiu com as áreas de maior incidência de baixo peso ao nascer e de altas concentrações de MP2,5. A análise espacial das concentrações de NO2 e MP2,5 mostrou áreas de maiores concentrações nas regiões onde ocorreram menores valores para o peso ao nascer, tendo como referência as principais vias de tráfego veicular. Quanto às concentrações de elementos-traço, observamos áreas de maior concentração de dos elementos traçadores de fontes de emissão veicular, cobre (Cu) e enxofre (S), próximos da via de tráfego rápido. A análise espacial permitiu avaliar tendências entre o peso do nascimento e a proximidade das vias de tráfego, embora de maneira descritiva. Conclusão: Houve uma associação entre peso ao nascer e as variações das concentrações de NO2 indoor, valor percentual de micronúcleos e identificação de Cu e S nas residências próximas às vias de tráfego rápido. Os resultados apontam caminhos para futuros estudos epidemiológicos de base individual utilizando medidas de exposição indiretas, ressaltando os bioindicadores vegetais como uma ferramenta útil para avaliação de exposição aos contaminantes atmosféricos / Introduction: Experimental and epidemiological studies have evidenced several side outcomes related with air pollution concentrations, highlighting pregnancy. The use of bioindicators has shown the impacts of air pollution on living organisms, including the plant specie Tradescantia pallida Objectives: The present study evaluated the effects of gestational exposure to air pollution regarding birth weight and the Tradescantia pallida responses to the same exposure conditions. The possible associations between exposure variables (NO2, MP2,5, foliar accumulation of trace-elements and traffic vehicular proximity of the mothers\' residence) and the effects variables (mutagenic response in T. pallida and birth weight) were also evaluated. Methodology: The cohort was comprised by 39 pregnant women residing in the Butantã district, São Paulo city. The residences, habits of its residents and the morbidity data were characterized by the application of a questionnaire. During 18 months, monthly samples of T. pallida leaves and inflorescences were collected. We applied the Tradescantia micronucleus bioassay (Trad-MCN) and measured the accumulation of traceelements in the leaves using EDXRF. The NO2, O3 and PM2,5 concentrations were measured in the residences and on the participants. Linear models were employed with birth weight as a dependent variable. The exposure and effects data were georeferenced and cartographically represented, using the chorochoromatic and isarithmic techniques with mothers\' residences and traffic vehicular proximity. The exposure and effects variables were represented by contour maps on the traffic routes basis of the study area. Results: The birth weight loss was 318,92g (IC 95% -578,44; -59,4) per interquartile range (20,02ug/m3) referent to indoor NO2 exposure in the third gestational trimester. This result showed the impact to NO2 exposure even when assessing other gestational risks variables. The evaluation of micronuclei percentage rate effect in the birth weight was related with 49,04g decrease in the birth weight (IC 95% = -121,83; 23,75). The map area with higher micronuclei percentage rate coincided with the low birth weight incidence areas and higher PM2,5 concentrations. The spatial analysis of the exposure variables (NO2 and PM2,5) exhibited same areas with higher pollutant concentrations and lower values for birth weight. The concentration of Cu (Cooper) and S (Sulfur) elements was predominantly close to the freeways. These analyses have allowed the evaluation of descriptive tendencies between birth weight and residential traffic proximity. Conclusion: There was an association between birth weight and indoor NO2 concentrations, micronuclei percent values and Cu and S identification on residences located close to freeways. These results suggest studies using both epidemiologic and indirect exposure measure approaches highlighting bioindicator plants as a useful tool for assessing the effects of air pollution in health

Des cultures de Chlorella vulgaris ont été réalisées en triplicata sur de longues périodes (15-30 jours) en autotrophie et en mixotrophie afin d’étudier l’effet de Mg2+ sur les microalgues et déterminer sa concentration dans la biomasse au cours de la croissance. Différentes concentrations ont été testées (de 8.9 à 465 mg L-1). Ceci a montré que le Mg2+ n’est pas toxique pour les algues à des concentrations élevées provoquant habituellement l’inhibition de la croissance dans le cas d’autres ions divalents (métaux lourds). Des bilans matière ont été établis et vérifiés avec une précision satisfaisante (écart moyen de 90%). La quantité de Mg2+ bioaccumulée augmente avec la concentration initiale de Mg2+ du milieu de culture. Une saturation en Mg2+ intracellulaire a été observée à partir d’environ 45 mg de Mg2+ L-1. Typiquement, la répartition entre le Mg2+ extracellulaire et intracellulaire est de 18% contre 51% dans le bioréacteur (5L) pour une concentration initiale de 16 mg L-1. En mixotrophie (addition de 10 g L-1 de glucose), une production de biomasse significativement plus importante et plus rapide que celle en autotrophie a été observée. En revanche, la quantité de Mg2+ accumulée dans les cellules est plus importante en autotrophie qu’en mixotrophie. Des mesures de chlorophylle a, de nitrate et de glucose ont été également réalisées. Afin de comprendre la cinétique relativement complexe de bioaccumulation du Mg2+, un modèle cinétique original a été élaboré couplant transfert (externe, membrane, interne) et réactions (ad/absorption) en milieu hétérogène. Le modèle a été validé expérimentalement. Il permet de rendre compte au mieux de l’ensemble des résultats obtenus. / Chlorella vulgaris cultures were grown in triplicate over 15-30 days under autotrophic or mixotrophic conditions in order to study Mg2+ uptake and accumulation into the biomass. The concentrations of Mg2+ tested were 8.9 to 465 mg L-1. The results showed that Mg2+ is not toxic to C. vulgaris even at 465 mg L-1 which is not the case for other divalent ions (especially heavy metals). The mass balances for Mg2+ accumulation were determined for the cultures and were confirmed to an average of 90%. Beyond 46.1 mg of Mg2+ L-1 in the culture medium, the cells became saturated at 4 mg of Mg2+ absorbed per g of dry biomass. In the bioreactor (5L), at an initial Mg2+ concentration of 16 mg L-1, the cells accumulated 69% of the initial concentration, in which 18% was adsorbed and 51% absorbed. The chlorophyll a, nitrate and glucose concentrations were measured during the experiments. Under mixotrophic conditions (glucose 10 g L-1), a greater and faster biomass production was obtained than under autotrophic conditions. The Mg2+ bioaccumulation was higher in the autotrophic rather than the mixotrophic phase. In order to understand the kinetics of Mg2+ uptake, an original kinetic model was developed coupling the transfer and reaction phenomena in heterogeneous media. This model was confirmed experimentally.

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 &#931;PCB, seguida do &#931;DDT 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/&#931;Dp,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 &#931;PCB predominance was observed, followed by &#931;DDT 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/&#931;Dp,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.

No description available.

Introdução: Estudos experimentais e epidemiológicos têm evidenciado diversos eventos mórbidos associados à poluição do ar, destacando os efeitos na gestação. A utilização de bioindicadores mostra os impactos da poluição em seres vivos, inclusive na espécie vegetal Tradescantia pallida. Objetivos: O presente estudo avaliou efeito da exposição gestacional à poluição do ar no peso ao nascer e a resposta à mesma exposição do bioindicador Tradescantia pallida. As possíveis associações entre as variáveis de exposição (NO2, MP2,5 acúmulo foliar de elementos-traço e proximidade residencial das vias de tráfego veicular) e as variáveis de efeito (resposta mutagênica em T. pallida e peso ao nascer) também foram investigadas. Metodologia: A coorte foi composta por 39 gestantes moradoras do distrito do Butantã, São Paulo, SP. Os domicílios, hábitos dos moradores e morbidade referida foram caracterizados pela aplicação de questionário. Durante 18 meses foram feitas coletas mensais de inflorescências e folhas de T. pallida. Foram utilizados os testes de quantificação de micronúcleos em tétrades de Tradescantia (Trad-MCN) e análise do acúmulo foliar de elementos-traço por EDXRF. Também foram medidos os níveis de NO2, O3 e MP2,5 nas residências, além de medidas individuais em cada gestante. A análise epidemiológica foi composta por análises de regressão linear univariada e múltipla tendo como variável dependente o peso ao nascer. Os dados de exposição e efeito foram georreferenciados e cartograficamente representados utilizando-se as técnicas corocromática e isarítmica, usando como base as residências das gestantes e a proximidade às vias de tráfego veicular, sendo representadas em mapas de isolinhas sobre a base de arruamentos da região. Resultados: Pelo modelo de regressão linear múltiplo, houve uma perda no peso ao nascer de 318,92g (IC 95% -578,44; -59,4) para o intervalo interquartil (20,02?g/m3) referente à exposição ao NO2 indoor no terceiro trimestre gestacional. Esse resultado mostra o impacto da exposição ao NO2 no peso ao nascer, mesmo avaliando outras variáveis de risco para esse desfecho gestacional. Houve uma associação entre o aumento do valor percentual médio de micronúcleos com a diminuição de 49,04g no peso ao nascer (IC 95% = -121,83; 23,75). Os maiores valores percentuais de micronúcleos medidos coincidiu com as áreas de maior incidência de baixo peso ao nascer e de altas concentrações de MP2,5. A análise espacial das concentrações de NO2 e MP2,5 mostrou áreas de maiores concentrações nas regiões onde ocorreram menores valores para o peso ao nascer, tendo como referência as principais vias de tráfego veicular. Quanto às concentrações de elementos-traço, observamos áreas de maior concentração de dos elementos traçadores de fontes de emissão veicular, cobre (Cu) e enxofre (S), próximos da via de tráfego rápido. A análise espacial permitiu avaliar tendências entre o peso do nascimento e a proximidade das vias de tráfego, embora de maneira descritiva. Conclusão: Houve uma associação entre peso ao nascer e as variações das concentrações de NO2 indoor, valor percentual de micronúcleos e identificação de Cu e S nas residências próximas às vias de tráfego rápido. Os resultados apontam caminhos para futuros estudos epidemiológicos de base individual utilizando medidas de exposição indiretas, ressaltando os bioindicadores vegetais como uma ferramenta útil para avaliação de exposição aos contaminantes atmosféricos / Introduction: Experimental and epidemiological studies have evidenced several side outcomes related with air pollution concentrations, highlighting pregnancy. The use of bioindicators has shown the impacts of air pollution on living organisms, including the plant specie Tradescantia pallida Objectives: The present study evaluated the effects of gestational exposure to air pollution regarding birth weight and the Tradescantia pallida responses to the same exposure conditions. The possible associations between exposure variables (NO2, MP2,5, foliar accumulation of trace-elements and traffic vehicular proximity of the mothers\' residence) and the effects variables (mutagenic response in T. pallida and birth weight) were also evaluated. Methodology: The cohort was comprised by 39 pregnant women residing in the Butantã district, São Paulo city. The residences, habits of its residents and the morbidity data were characterized by the application of a questionnaire. During 18 months, monthly samples of T. pallida leaves and inflorescences were collected. We applied the Tradescantia micronucleus bioassay (Trad-MCN) and measured the accumulation of traceelements in the leaves using EDXRF. The NO2, O3 and PM2,5 concentrations were measured in the residences and on the participants. Linear models were employed with birth weight as a dependent variable. The exposure and effects data were georeferenced and cartographically represented, using the chorochoromatic and isarithmic techniques with mothers\' residences and traffic vehicular proximity. The exposure and effects variables were represented by contour maps on the traffic routes basis of the study area. Results: The birth weight loss was 318,92g (IC 95% -578,44; -59,4) per interquartile range (20,02ug/m3) referent to indoor NO2 exposure in the third gestational trimester. This result showed the impact to NO2 exposure even when assessing other gestational risks variables. The evaluation of micronuclei percentage rate effect in the birth weight was related with 49,04g decrease in the birth weight (IC 95% = -121,83; 23,75). The map area with higher micronuclei percentage rate coincided with the low birth weight incidence areas and higher PM2,5 concentrations. The spatial analysis of the exposure variables (NO2 and PM2,5) exhibited same areas with higher pollutant concentrations and lower values for birth weight. The concentration of Cu (Cooper) and S (Sulfur) elements was predominantly close to the freeways. These analyses have allowed the evaluation of descriptive tendencies between birth weight and residential traffic proximity. Conclusion: There was an association between birth weight and indoor NO2 concentrations, micronuclei percent values and Cu and S identification on residences located close to freeways. These results suggest studies using both epidemiologic and indirect exposure measure approaches highlighting bioindicator plants as a useful tool for assessing the effects of air pollution in health

This thesis focussed on the effects of a range of trace metals on various stages of Haliotis rubra development. The trace metals assessed in this thesis were the essential metals Cu, Zn and Fe; and, the non-essential metals Hg, Cd and Pb. Copper and Hg proved to be the two most toxic metals to the life stages of H. rubra studied. The concentrations affecting normal development of the fertilised egg exposed for 48h showed a decreasing order of toxicity with 48hEC50 recorded at 7µg Cu/L, 20µg Hg/L, 42µg Zn/L, 4,102µg Fe/L, 4,515µg Cd/L, and 5,111µg Pb/L. Settlement and metamorphosis occur in normal larvae when aged 5 days, and exposure of the 5 day old larvae to the metals for 48h resulted in impaired crawling success at 128µg/L Cu and Hg, and 1250µg Cd/L. Settlement was inhibited after exposure to 128µg Cu/L, 32µg Hg/L, and 1250 Cd/L. Metamorphosis of larvae 96h after exposure was inhibited by 32µg Cu/L, 512µg Zn/L, 32µg Hg/L and 625µg Cd/L. The rate of meta morphosis was enhanced after exposure to Cu and Hg at 0.5µg/L and 64 - 256µg Zn/L. Exposure to Zn at concentrations 64, 128 and 256 µg Zn/L caused an increased rate of settlement and metamorphosis. Juvenile H. rubra exposed to the six metals for 96h were most sensitive to Cu, which produced a 96hLC50 of 87µg Cu/L compared to Hg with a 96hLC50 of 173µg Hg/L. Juvenile H. rubra were relatively insensitive to Zn and Cd with the 96h LC50 of 1730µg Zn/L and 3700µg Cd/L, respectively. Exposure to individual solutions of Cu, Zn, and Cd for 28 days resulted in juvenile H. rubra bioaccumulating significant concentrations of metals in the visceramantleedible foot muscle. Accumulation of Hg was greater in the mantle-viscera-edible foot muscle. Following exposure, depuration in clean seawater for 28 days produced varying decreases in metal concentrations for each tissue compartment. Sodium-potassium activated ATPase (Na+,K+-ATPase) activity in the gills of juvenile H. rubra was significantly affected following expos ure to the trace metals for 28 days, with a decreasing order of effect on enzyme activity of Hg-Cu-Cd-Zn. Depuration of H. rubra in clean seawater for 28 days resulted in the recovery of Na+,K+-ATPase activity to varying degrees. The recovery of ATPase activity was more efficient following exposure to Cd-Zn-Cu-Hg. The overall results of this thesis provide initial baseline information to evaluate the sensitivity of H. rubra to trace metal toxicants, and these results may be utilised by regulators for establishing marine water quality guidelines to protect H. rubra and other abalone species in their natural habitats.