La production et l’utilisation des nanomatériaux manufacturés est en plein essor, ce qui entraîne leur déversement dans l’environnement sous forme de nanoparticules ou de sous produits d’altération. Les nanoparticules de dioxyde de titane sont utilisées dans un grand nombre de produits manufacturés du fait de leurs propriétés photocatalytiques et d’absorption des UV. Les risques écotoxicologiques liés aux nanoparticules de TiO2 et aux sous produits d’altération de TiO2 sur les organismes terrestres sont encore peu connus. A cette fin, des vers de terre ont été utilisés car ce sont des indicateurs clés de la qualité des écosystèmes terrestres. L’espèce Eisenia fetida employée présente l’avantage d’être facile à manipuler et est utilisée dans des tests normalisés d’écotoxicité. La toxicité potentielle des nanoparticules de TiO2 et des sous produits d’altération de TiO2 sur Eisenia fetida a été étudiée selon différentes approches: un test in vitro sur les nanoparticules de TiO2 (1 à 25 µg/ml), une exposition in vivo en milieu liquide contaminé par des SPA de TiO2 (0,1 à 10 mg/l) et une exposition in vivo en milieu solide dans des sols artificiels contaminés par des nanoparticules de TiO2 (2 à 200 mg/kg) ou par des sous produits d’altération de TiO2 (2-20 mg/kg). La toxicité des nanomatériaux de TiO2 a été évaluée en utilisant une batterie de biomarqueurs à différentes échelles biologiques : la survie et la reproduction à l’échelle de l’individu, la viabilité cellulaire (test MTT et LDH), la phagocytose et l’apoptose à l’échelle cellulaire et l’expression des ARNm des gènes des systèmes de détoxication (métallothionéine, GST), antioxydant (SOD, CAT) et immunitaire (CCF et fétidines) par RT-qPCR à l’échelle moléculaire. Nos résultats ont montré que les nanoparticules de TiO2 sont internalisées par les cellules immunitaires des vers de terre (in vitro) et que le titane est bioaccumulé par les vers exposés aux sous-produits d’altération de TiO2 dans des conditions d’exposition artificielle (milieu liquide). Seuls les biomarqueurs moléculaires (métallothionéine, CCF et fétidines) sont sensibles aux nanoparticules de TiO2 dans le test in vitro alors que les biomarqueurs moléculaire (métallothionéine et SOD) et cellulaire (apoptose et phagocytose) répondent aux sous-produits d’altération de TiO2 en milieu liquide après seulement 24h d’exposition. En revanche, dans des conditions d’exposition plus réalistes, aucun effet biologique sur la survie, la reproduction et l’expression des ARNm des gènes de détoxication, antioxydant et immunitaire n’a été observé sur les vers exposés aux sols contaminés. La faible biodisponibilité des nanomatériaux de TiO2 dans les matrices solides expliquerait l’absence d’effet biologique aux concentrations testées. Ces travaux soulignent la nécessité d’étudier le comportement, la mobilité, et la biodisponibilité des nanomatériaux avant d’évaluer leur potentielle écotoxicité. / The amount of nanomaterials produced annually is constantly increasing and this trend may result in a strong input of manufactured nanoparticles in air, water, soils, and therefore in contact with organisms. Among the manufactured nanoparticles, titanium dioxide (TiO2) nanoparticles have been produced massively for their photocatalytic properties and UV absorption ability. Surprisingly, ecotoxicological risks associated with TiO2 nanoparticles and TiO2 byproducts resulting from the alteration and aging of nanomaterials are poorly documented on terrestrial organisms. The potential toxicity of TiO2 nanoparticles and TiO2 byproducts on the earthworm Eisenia fetida has been evaluated, using different approaches: the first with in vitro assay to determine toxicity of TiO2 nanoparticles (1 to 25 µg/ml), the second with in vivo exposure of earthworm to liquid medium contaminated by TiO2 byproducts (0.1 to 10 mg/l) and the third with in vivo exposure to artificial soil contaminated by TiO2 nanoparticles (2 to 200 mg/kg) or TiO2 byproducts (2-20 mg/kg). Ecotoxicity of TiO2 nanomaterials was determined using a battery of biomarkers at different biological levels: survival and reproduction at individual level, cell viability (MTT and LDH assay), phagocytosis and apoptosis at cellular level, mRNA expression of detoxification (metallothioneins, GST), antioxidant (SOD, CAT) and immunes genes (CCF and fetidins) by RT-qPCR at molecular level. Our results showed that TiO2 nanoparticles were internalized by immune cells (in vitro assay) and titanium was bioaccumulated by worms exposed to TiO2 byproducts in artificial exposure assay (liquid medium). Molecular biomarkers (metallothioneins, CCF and fetidins) were sensitive to TiO2 nanoparticles after in vitro exposures, while both molecular (metallothioneins and SOD) and cellular (phagocytosis, apoptosis) biomarkers were sensitive to TiO2 byproducts in liquid medium after only 24 hours of exposure. In contrast, in more realistic conditions of exposure, no effect on life-history traits or molecular biomarker were noticed on earthworms exposed to soils contaminated by TiO2 nanoparticles or byproducts. A low bioavailability of TiO2 nanomaterials in soil matrixes could explain the lack of effect at the concentrations tested. These results underline the necessity to evaluate mobility, behaviour and bioavailability of nanomaterials in soil matrixes before their ecotoxicity assessment.

Les activités métallurgiques entrainent l'accumulation d'éléments traces métalliques dans les couches . superficielles des sols, où l'on peut observer des concentrations largement supérieures au fond pédogéochimique et aux normes en vigueur. La contamination des sols est une menace pour la santé publique et la présence de grandes quantités d'éléments traces métalliques peut générer un stress susceptible d'affecter les organismes exposés à des sols pollués. Les Annélides Oligochètes vivent en contact étroit avec ces sols pollués et sont parmi les organismes vivants présentant une sensibilité exacerbée aux métaux. Très peu de choses sont connues quant à l'identification et la mise en place des mécanismes de réponse à ces métaux au niveau moléculaire. En exploitant, la conservation phylogénique observée entre espèces nous avons été capables de cloner et de caractériser un ensemble de biomarqueurs de pollution potentiels à partir des cœlomocytes de l'Annélide Oligochètes Eisenia fetida. Deux approches ont été mises en place. Premièrement, une approche qualifiée de ciblée, consistant à identifier tous les effecteurs parmi des protéines fortement conservées pour lesquels une variation lors d'une exposition métallique était reportée dans la littérature. Deuxièmement, nous avons entrepris une approche qualifiée de globale consistant en la construction de banques soustractives pour identifier chez Eisenia fetida, les gènes dont l'expression est affectée lors d'une exposition à un mélange complexe de métaux, représentatif d'un site naturel fortement contaminé. Ces deux approches ont permis l'identification de 4 candidats biomarqueurs de pollution métallique. / Metallurgical activities lead to accumulation of metal trace elements in the topsoils, where one typically observes concentrations largely exceeding the natural background. Contaminations of soils are a threat for public health and the presence of high amount of metals can generate an environmental stress likely to affect the organisms exposed to polluted soils. Earthworms living in close contact with polluted soils were studied in order to better understand the physiological changes, the mechanisms of acclimation and of detoxification caused by metals. By exploiting the conservation observed between species and using molecular biology techniques, we have been able to clone and transcriptionally characterise potential biomarkers form the immune ceIls of the ecotoxicologically important earthworm species Eisenia fetida. During this Ph. D. we developed two approaches. First, a targeted approach based on bibliographie work, enabled us to identify and select effectors among highly preserved proteins for which variations following metal exposure were reported in invertebrates. Second, an open strategy was undertaken by performing a Suppression Subtractive Hybridization in order to identify genes which are differentially expressed following exposure to a complex mixture of metals representative of a strongly polluted soil. These approaches allowed the description of a group of genes which expression varies following metallic exposure as weIl as the analysis of their expression profiles may be used to analyse mechanistically the immune response to a metallic stress. Moreover, expression profiles of selected genes may constitute a signature of changes due to MTE.

Thesis (Ph. D.)--Ohio State University, 2009. / Title from first page of PDF file. Includes vita. Includes bibliographical references (p. 90-95).

Le vermicompostage est une éco-biotechnologie relativement nouvelle qui utilise des vers de terre comme bioréacteurs naturels dans un procéssus de décomposition de la matière organique. En Europe, on utilise trois espèces d’annélides oligochètes : Eisenia fetida, Eisenia andrei et Dendrobaena veneta. Compte tenu des directives de l’Union Européenne portant sur le traitement des déchets, les contenus en métaux lourds, en composés chimiques divers et en microorganismes pathogènes des boues d’épuration ne permettent pas leur valorisation directe en agriculture. La qualité du produit obtenu après vermicompostage peut être évaluée en utilisant des paramètres agronomiques, tandis que des paramètres immunitaires et de défense mesurés chez les vers permettent d’apprécier l’impact des contaminants sur ces organismes du sol. Les objectifs de ce travail étaient: 1) apprécier l'influence des vers de terre sur la qualité du produit final dans le processus de lombricompostage, 2) examiner les mécanismes moléculaires et immunologiques mis en œuvre chez les lombrics au cours du lombricompostage de boues d'épuration urbaines, 3) de développer le compostage combiné au processus de lombricompostage. Les vers de terre utilisés dans les travaux présentés ont été classés en trois espèces grâce à la technique de barcoding moléculaire. Les fluorophores sélectionnés ont été testés comme les biomarqueurs spécifiques à l’espèce. Le contenu en riboflavine, le nombre de coelomocytes (amébocytes/éléocytes) et le niveau d’expression de gènes sélectionnés ont été utilisés comme biomarqueurs de stress permettant la bio-oisurvéillance du processus. La technique appliquée a conduit à évaluer les possibilités de valorisation des boues d'épuration. / Vermicomposting is a relatively new eco-biotechnology using earthworms as natural bioreactors in the process of decomposition of organic matter. Eisenia andrei, Eisenia fetida and Dendrobaena veneta are detrivorous organisms that enhance the decomposition of complex organic compounds and influence circulation of organic matter. This eco-technique is a non-expensive method of biodegradation of organic wastes, inter alia sewage sludge. Due to the high content of various pollutants, including heavy metals, chemicals and pathogenic microorganisms, sewage sludge cannot be directly used in agriculture. The quality of the product can be assessed using agronomic parameters, while immune and defense parameters can be measured as stress biomarkers. Aims of this work were: 1) to determine the influence of earthworms on the quality of the product obtained in vermicomposting process, 2) to investigate the molecular and immunological mechanisms occurring in earthworms during vermicomposting of municipal sewage sludge, 3) to develop the combined composting – vermicomposting process. Earthworms were segragated into three separate groups basing on DNA barcoding and selected fluorophores were tested as non-invasively retrieved biomarkers allowing distinction between morphologically similar composting earthworm species. Riboflavin, coelomocytes (amoebocytes/eleocytes) composition and particular gene expression levels were selected as biomarkers of stress useful in biomonitoring of the vermicomposting process. Applied technique has led to assess the possibilities of valorization of sewage sludge.

Les boues d’épuration des eaux usées, produites en grandes quantités partout dans le monde, sont riches en matière organique et leur utilisation en tant que conditionneur de sol présente un intérêt potentiel. Cependant, la présence de polluants et notamment de contaminants non biodégradables tels que des métaux (Éléments Traces Métalliques: ETMs) peut limiter leur utilisation en agriculture et constitue un défi pour la protection de l'environnement. Le lombricompostage, processus biologique dans lequel des vers de terre sont utilisés pour accélérer la dégradation des déchets organiques, peut être appliqué aux boues. Des travaux ont montré que les vers peuvent accumuler certains ETMs et modifier leur biodisponibilité dans le compost. L'objectif principal de cette thèse est d'évaluer le lombricompostage en tant que processus de valorisation des boues d'épuration urbaines. Après une analyse bibliographique, des expérimentations en conditions contrôlées ont été réalisées afin d’évaluer l'efficacité du lombricompostage appliqué à différents boues (profils de contamination différents) et en utilisant différentes espèces de vers. Le compostage des boues en présence d’autres déchets a également été analysée. La qualité agronomique du compost a été évaluée de même que les capacités de tolérance de 3 espèces de vers et leur aptitude à accumuler plusieurs ETMs. Le traitement par lombricompostage a permis une réduction considérable de la masse du mélange traité et a considérablement changé les teneurs métalliques dans le compost obtenu. Globalement, le produit final présente des paramètres agronomiques acceptables au regard des normes de qualité en vigueur en France et en Pologne. / Large sewage sludge quantities are produced in wastewater plants, worldwide. Sewage sludge is rich in organic matter and its use as soil conditioner might be of interest. However, pollutants and especially non-biodegradable contaminants such as metallic trace elements (MTEs) are present in sludge. This may prevent the use of sewage sludge in agriculture and constitutes a challenge for environmental protection. Vermicomposting is an eco-friendly process in which earthworms are used to accelerate the degradation of organic wastes. Moreover, earthworms have shown an ability to accumulate MTEs and change the bioavailability of MTEs in compost. The main aim of this thesis was to evaluate the vermicomposting process applied to urban sewage sludge. After a bibliographic synthesis, experiments in controlled conditions have been performed in order to assess the effectiveness of vermicomposting applied to different sewage sludge (exhibiting contrasted contamination levels) and using different earthworm species. The mixing of different sewage sludge with other organic wastes has also been analyzed. The capacity of earthworms to accumulate several metals and their resistance to different contamination levels were also examined. Compost agronomic quality was assessed as well as the tolerance capabilities of three earthworm species and their ability to accumulate several MTEs. Vermicomposting treatment led to a significant reduction of the treated mixture weight and has significantly changed the content of several metals in the final product. Overall, vermicomposts were acceptable according to agronomic parameters and to compost quality norms in France and in Poland.

Chromated copper arsenate (CCA), type C, was largely used as a wood preservative due to its exceptional fungicidal and insecticidal properties. Although this treatment was prohibited for residential purposes in Canada and in the United-States of America, concerns about CCA-treated wood focus on the possible threat on human health and the contamination of the environment, through the leaching of metals from existing structures. The objectives of this thesis are (1) to assess the effects of metals leached from CCA- and ACQ-treated wood on the survival, the growth and the reproductive success of the earthworm Eisenia fetida (Annelida, Oligochaeta), and (2) to evaluate if annetocin, a neuropeptide linked to reproduction, could be used as a biomarker of ecotoxicological responses of the worm E. fetida when exposed to metals from the CCA treatment. Ecotoxicological tests with E. fetida were carried out according to the protocol ISO-11268-2. (Abstract shortened by UMI.)

No description available.

The theoretical part is devoted to the production of vermi compost, earthworm breeding and arbuscular mycorrhizal symbiosis. The practical part of the procedure followed in establishing containter experimentwith lettuce (Lactuca sativa), further evaluation and processing of results in tables and graphs. The aim was to experimentally determine the effect on plant growth vermi compost. Furthermore, it aims to validate the influence of colonization root mycorrhizal fungi. Effect of vermi compost to an average dry weight of aboveground and underground materials was confirmed and significant difference was observed. Vermi compost had also an influence on the length outer root root hyphae per cm2 membrane filter. Impact on the percentage of root colonization was clearly confirmed. In addition, as of Symbivit mycorrhizal positive influence on above and below ground biomass and the length outside the root hyphae. Impact on the percentage of root colonization was not significantly manifested.

Memoria para optar al título profesional de Ingeniero Agrónomo Mención Fitotecnia / El sustrato o medio de cultivo es uno de los factores de mayor relevancia en la producción de plantines de hortalizas, básicamente porque es el encargado de proveer el soporte, la aireación, el agua, y en algunos casos la nutrición del sistema radical de la planta. En los últimos años, ha crecido el interés por utilizar sustratos alternativos a los usados hasta hoy, en donde el humus de lombriz se presenta como una clara opción. El presente ensayo se desarrolló con el objetivo de evaluar el efecto de fórmulas de sustratos a base de humus de lombriz, en la calidad de plantines de lechuga Lactuca sativa L. cv. Winterhaven y repollo Brassica oleracea var capitata L. cv. Savoy Ace. Se evaluaron cinco mezclas de sustratos, las cuales contenían humus de lombriz, turba y perlita, más un testigo (70% turba y 30% perlita). Al mismo tiempo estas mezclas de sustratos se caracterizaron física, química y biológicamente. El diseño experimental fue de bloques completos aleatorizados con seis tratamientos y cinco repeticiones para cada especie. Para ambas especies se evaluó el desarrollo de plantines desde emergencia hasta 3-4 hojas verdaderas, además de mediciones al momento del transplante y luego en campo al cabo de 21 días. Producto del seguimiento que se hizo a cada especie, se determinó que el humus de lombriz otorga cierta precocidad en la producción al estado de 3-4 hojas verdaderas, sobretodo en repollo. Asimismo, para ambas especies, al momento del transplante se observó un mayor crecimiento de los plantines producidos en la mezcla que contenía un 70% de humus de lombriz, siendo esto más evidente para repollo. En cuanto a las mediciones realizadas en campo 21 días luego del transplante, se constató que para ambas especies el tratamiento de mejor comportamiento correspondió al que contenía un 56% de humus de lombriz. Por lo tanto, se puede concluir que el humus de lombriz como componente de sustratos tiene efecto positivo sobre el crecimiento y desarrollo de plantines de repollo y lechuga, lo cual también es evidente en campo 21 días después del transplante. / The substrate is one of the most relevant aspects in vegetables seedling production, basically because it is responsible to provide support, air, water, and in some cases nutrients to the plant root system. In recent years, the interest to use alternative substrates has grown, and earthworm humus is presented like a clear choice. The present study was developed with the objective to evaluate the effect of different substrates formulas based on earthworm humus, in lettuce (Lactuca sativa L. cv. Winterhaven) and cabbage (Brassica oleracea var capitata L. cv. Savoy Ace) seedlings. Five substrates mixtures were evaluated, which contained earthworm humus, peat, perlite and a control (70% peat and 30% perlite). At the same time, the substrates mixtures were characterized by physical, chemical and biological analysis. For each species, a randomized complete block design with six treatments and five replicates was used. Seedling development from emergency to 3-4 true leaves, in addition to measurements at the transplant moment and 21 days after transplant were measured for each species. As a result of monitoring each species, it was determined that the earthworm humus at 3-4 true leaves give certain precocity in the production, moreover in cabbage. Also, for both species, at transplant moment, it was observed a major seedling growth in the 70% earthworm humus mix, becoming more evident in cabbage. Regarding the measurement at 21 days after transplant, both species verified that the treatment with the best behavior was the 56% earthworm humus substrate. Therefore, it can be conclude that earthworm humus like substrate component have a positive effect over seedling growth and development, which was also evident in field at 21 days after transplant.

Nas últimas décadas tem-se verificado um significativo aumento na quantidade de contaminantes que são liberados no ambiente, destacando-se os agrotóxicos como um dos mais utilizados e nocivos. Os agrotóxicos são utilizados para o controle de doenças, pragas e plantas invasoras e, apesar de sua eficiência, seus efeitos em nível de ecossistema e saúde humana são preocupantes. No município de Bom Repouso/MG, devido à prática agrícola há intenso uso de agrotóxicos, os quais são aplicados nas lavouras de morango e batata sem controle mais efetivo, não sendo verificada nenhuma avaliação ambiental física, química e biológica, ou que incluísse os testes de toxicidade terrestres. Dentro desse contexto, o presente estudo procurou avaliar a aplicabilidade dos testes ecotoxicológicos padronizados internacionalmente para organismos terrestres, além de avaliar os impactos ambientais decorrentes das atividades agrícolas no município de Bom Repouso. Para tanto, ensaios de toxicidade (testes de evitamento, toxicidade aguda e crônica) com a espécie Eisenia andrei (ANNELIDA, OLIGOCHAETA), além de análises físicas e químicas, foram realizados com amostras de solo coletadas nas monoculturas de morango e batata, e em área de mata preservada. Nas análises físicas e químicas dos solos foram detectadas concentrações de metais e agrotóxicos em concentrações abaixo de valores orientadores definidos em legislação vigente, ressaltando-se que ambos também ocorreram em áreas de mata preservada. Elevadas concentrações de alumínio foram detectadas nos solos, porém não existem valores orientadores estabelecidos e provavelmente são características do tipo de solo da área de estudo. Não foi verificada toxicidade aguda aos organismos-teste, enquanto que nos testes de evitamento verificou-se que os organismos evitaram os solos de área de cultivo de morango e batata, preferindo os da mata; porém não é possível afirmar se esse resultado se deve à presença de contaminantes ou às propriedades físicas e químicas dos solos. Em relação aos efeitos subletais, a perda de peso não foi caracterizada como efeito de toxicidade, e os efeitos sobre a reprodução, para a maioria dos solos testados, não foram significativos, com exceção de duas amostras coletadas em área de mata e uma amostra de área de batata. Este resultado pode ter sido influenciado pelas concentrações de agrotóxicos não detectados (mas identificados em estudos anteriores), embora as características ácidas do solo também possam ter maior representatividade. Especificamente para as áreas de mata, as concentrações de alumínio detectadas nos solos e a dificuldade de ajuste de umidade provavelmente também influenciaram os resultados. Em função dos resultados obtidos, verifica-se que ainda são necessárias alterações nos procedimentos dos testes ecotoxicológicos com organismos terrestres, com adaptações para testes com amostras de solos naturais. Em relação ao município de Bom Repouso, são evidentes os problemas ambientais decorrentes do uso de agrotóxicos, sendo necessária uma avaliação de risco que permita uma visão sistêmica da situação ambiental e de saúde dos moradores da região. / In the last decades there has been a significant increase in the amount of contaminants that are released into the environment, especially pesticides as one of the most used and harmful. The pesticides are used to control diseases, plagues and invaded plants and, despite its efficiency, its effects on the ecosystem level and human health are disturbing. In the Bom Repouso/MG municipality, due to the agricultural practice, there is an intensive use of pesticides, which are applied in strawberry and potato crops without more effective control, and it is not checked any biological, chemical and physical environmental assessment, which would include tests for terrestrial toxicity. In this context, this current study sought to evaluate the applicability of ecotoxicological tests internacionally standardized for terrestrial organisms and to evaluate the environmental impacts of agricultural activities in the Bom Repouso/MG municipality. Therefore, toxicity tests (tests of avoidance, chronic and acute toxicity) with the species Eisenia andrei (ANNELIDA, OLIGOCHAETA), in addition physical and chemical analysis, were performed with soil samples collected from monocultures of strawberry and potato, in addition preserved forest. In the chemical and physical analysis of the soils were detected concentrations of metals and pesticides in concentrations below the guiding values defined in current legislation, emphasizing that both also occurred in areas of preserved forest. High concentrations of aluminum were detected in soils, but there are no established guinding values and probably these are characteristics of the soil type of the study area. It was not observed acute toxicity to the test-organisms, whereas in tests of avoidance, it was observed that the organisms avoided the soils of the cultivation of strawberry and potato, preferring the forest, but it is not possible to state whether this result is due to the presence of contaminants or the chemical and physical properties of the soils. With respect to the sub lethal effects, the weight loss was not characterized as an effect of toxicity, and the effects on reproduction, for the most soils tested, were not significant, except for the two samples collected in the forest area and one sample in the potato area. This result may have been influenced by the concentrations of pesticides not detected (but identified in previous studies), although the acid soil characteristics may also have greater representation. Specifically for the forest areas, the concentration of aluminum detected in soils and the difficulty of the moisture adjusting, probably also influenced the results. Depending on the results, it observes that are still necessary changes in the procedures ecotoxicological tests with terrestrial organisms, with adjustments for tests with samples of natural soils. With reference to the Bom Repouso municipality, are obvious the environmental problems and because of the use of pesticides, it is necessary an assessment risk that allows a systemic view of the environmental situation and of the health of region residents.