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

Ecotoxicological studies of tributyltin (TBT), using indicatoe species Nucella lapillus (L.)

Spence, S. K. January 1989 (has links)
No description available.
2

Carbonic anhydrase in marine organisms

Mudge, Stephen Michael January 1986 (has links)
No description available.
3

The levels and effects on tin and copper on shellfish from Strangford Lough, Co. Down

Boal, Deborah Catherine January 1990 (has links)
No description available.
4

Polyfluorinated acrylates as antifoulants

Stone, Maureen January 1999 (has links)
No description available.
5

An investigation of the biology of marine fouling microorganisms with special reference to biocide control

Jackson, S. M. January 1988 (has links)
No description available.
6

The bioavailability of sediment-bound tributyltin (TBT)

Dingle Pope, Nicholas January 1998 (has links)
Tributyltin is arguably the most toxic compound ever to be deliberately introduced into the marine environment as an ingredient of antifouling paints. It has had widespread toxic effects on a range of marine organisms, with some gastropod species being particularly sensitive. Effects of TBT on non-target species have resulted in partial bans on its use in many countries, so that new inputs to the water column have decreased in most areas. One of the physicochemical features of TBT is that it is readily sequestered by suspended particulates due to its low solubility and its hydrophobicity, therefore becoming incorporated into estuarine sediments. The availability of this sediment-bound TBT has been investigated through its potential for re-release back to the water column, and directly from the sediment using the sediment dwelling gastropod Hinia reticulata. The sorption process itself has been investigated using natural components to determine the sediment-water partition coefficient (Kd) together with factors affecting its magnitude. Sorption by sediments has been shown to be rapid (minutes), although the achievement of equilibrium may take longer (hours), and exhibits a Freundlich-like dependence on the TBT concentration due to the variable energies of TBT sorption sites on sediment particles. The major determinant of Kd is sediment type, greater adsorption occurring in fine-grained organic rich sediments compared to low organic sands; although both salinity and pH modify the degree of adsorption. The sorption process has been shown to be reversible, so that previously contaminated sediments may act as reservoirs of TBT, releasing the compound back to the overlying water for many years. Hinia reticulate has been shown to be an effective and quantitative accumulator of both dissolved and sediment-bound TBT, principally acquiring TBT from water across the respiratory surfaces. When additionally exposed to sediments, significantly higher body burdens were accumulated, with up to 80% of the total attributable to the sediment. Uptake of TBT across the surface of the headtfoot appears to be an important pathway for sediment-exposed Hinia reticulata, while the ingestion of contaminated sediment does not appear to occur. Hinia reticulata is capable of metabolising TBT to lesser butylated and presumably less toxic products which are excreted, making its accumulated body burdens responsive to changing environmental TBT levels, and increasing its value as a biomonitor When exposed to a range of TBT contaminated sediments, Hinia reticulata showed there to be greater TBT availability from sediments with a low sorptive capacity (sands), principally through desorption of TBT to the overlying water. Fine-grained organic-rich muds, which have a greater capacity for TBT, produced lower accumulated burdens in Hinia reticulata, but may represent more important long-term sources of TBT to benthic organisms in estuaries.
7

Use and environmental impact of antifouling paints in the Baltic Sea

Bighiu, Maria Alexandra January 2017 (has links)
Biocide-based antifouling (AF) paints are the most common method for preventing biofouling, i.e. the growth of algae, barnacles and other organisms on boat hulls. AF paints for leisure boats are predominantly based on copper (Cu) as the main biocide, with zinc (Zn) present as a pigment and stabilizer. Both metals are released from the paint matrix into the water column, leading to contamination of marinas which typically have only limited water exchange. Thus, the aim of this PhD thesis was to describe the use of AF paints in different regions in Sweden, as well as the associated environmental consequences with regard to contamination of the environment and toxicity to non-target aquatic snails. Using a recently developed X-ray fluorescence application, high levels of Cu were detected on boats moored in freshwaters, despite a more than 20-year-old ban, as well as high levels of tin (Sn) on 10 % of the boats, indicating the presence of (old) tributyltin paints (TBT), which might pose an environmental risk and a health hazard for people performing the paint scraping (paper 1). In addition, very high levels of Cu and Zn were measured in the biofouling material collected from the boat hulls, and this is problematic because the biofouling is commonly disposed of on the soil in boatyards at the end of each season. No difference was found in the amount of biofouling on boats coated with Cu or biocide-free paints, which implies that Cu might be currently overused in areas of low salinity and low barnacle density (paper 2). This work also introduces the use of a new species for ecotoxicological field experiments, the snail Theodoxus fluviatilis. Chronic field experiments (paper 3) revealed 6-fold increases in snail mortality, negative growth and up to 67-fold decreased reproduction in marinas, compared to areas not impacted by boating (‘reference areas’). Moreover, a higher prevalence of snails with histopathological alterations (e.g. necrosis of gills, gonads, midgut gland and parasite infestation, among others) was observed in the marinas, compared to the reference areas (paper 4). Statistical modelling indicated that the majority of the toxic effects were best predicted by the metals, most likely originating from AF paints. The results presented in this thesis depict some important aspects of AF paint use in brackish water and highlight the necessity of implementing a suitable management practice for the heavily contaminated biofouling waste in order to minimize the risk to soils. In addition, the evidence of toxicity to snails in marinas can be used as a basis to increase the public understanding of the impact of recreational boating and encourage people to choose less toxic alternatives to AF paints. / <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>
8

Análise cromatografica de biocidas anti-incrustantes em amostras de água de mar e tecido de moluscos / Chromatographic analysis of booster antifouling biocides in seawater samples and molluscs tissue

Diniz, Lia Gracy Rocha 02 September 2016 (has links)
A indústria naval é uma das mais importantes para economia e desenvolvimento de um país, no entanto, as diversas atividades desenvolvidas em zonas portuárias contribuem para o impacto ambiental a ambientes costeiros, dentre os vários grupos de micropoluentes orgânicos potencialmente danosos a esses ecossistemas, emergiram nos últimos anos os biocidas anti-incrustantes. Pinturas anti-incrustantes são tratamentos utilizados para minimizar processos corrosivos, diminuindo custos com manutenção, economizando combustíveis e reduzindo a veiculação de espécies não nativas entre ecossistemas costeiros. Neste estudo foi desenvolvido, validado e aplicado um método analítico para determinação dos biocidas anti-incrustantes, clorotalonil, diuron, irgarol e tiram em amostras de água, e tecido biológico em diferentes regiões portuárias da costa brasileira e da Ilha de Gran Canaria -Espanha. / The maritime industry is an important aspect of a countries economy, however, the cumulative activities of port areas has an impact on coastal environments, this can include the addition of harmful micro-organic material. Among the potentially harmful micro-organic material being added to ecosystems, are recently emerged anti-fouling biocidal paints. Anti-fouling paints are used as a treatment to minimize corrosive processes, reduce maintenance costs, save fuel and reduce the transmission of non-native species to coastal ecosystems. This study developed, validated and applied an analytical method for the determination of the anti-fouling biocidal paints, chlorothalonil, diuron, irgarol and tiram in water samples and biological tissue in different port areas of the Brazilian coast and the Gran Canaria Island in Spain.
9

Análise cromatografica de biocidas anti-incrustantes em amostras de água de mar e tecido de moluscos / Chromatographic analysis of booster antifouling biocides in seawater samples and molluscs tissue

Lia Gracy Rocha Diniz 02 September 2016 (has links)
A indústria naval é uma das mais importantes para economia e desenvolvimento de um país, no entanto, as diversas atividades desenvolvidas em zonas portuárias contribuem para o impacto ambiental a ambientes costeiros, dentre os vários grupos de micropoluentes orgânicos potencialmente danosos a esses ecossistemas, emergiram nos últimos anos os biocidas anti-incrustantes. Pinturas anti-incrustantes são tratamentos utilizados para minimizar processos corrosivos, diminuindo custos com manutenção, economizando combustíveis e reduzindo a veiculação de espécies não nativas entre ecossistemas costeiros. Neste estudo foi desenvolvido, validado e aplicado um método analítico para determinação dos biocidas anti-incrustantes, clorotalonil, diuron, irgarol e tiram em amostras de água, e tecido biológico em diferentes regiões portuárias da costa brasileira e da Ilha de Gran Canaria -Espanha. / The maritime industry is an important aspect of a countries economy, however, the cumulative activities of port areas has an impact on coastal environments, this can include the addition of harmful micro-organic material. Among the potentially harmful micro-organic material being added to ecosystems, are recently emerged anti-fouling biocidal paints. Anti-fouling paints are used as a treatment to minimize corrosive processes, reduce maintenance costs, save fuel and reduce the transmission of non-native species to coastal ecosystems. This study developed, validated and applied an analytical method for the determination of the anti-fouling biocidal paints, chlorothalonil, diuron, irgarol and tiram in water samples and biological tissue in different port areas of the Brazilian coast and the Gran Canaria Island in Spain.
10

Subsídios para gestão ambiental dos impactos das tintas anti-incrustantes no brasil /

Rojas, Erika Guisande January 2019 (has links)
Orientador: Teodoro Vaske Junior / Resumo: A utilização de tintas anti-incrustantes é mandatória para embarcações e outras estruturas submersas na água do mar. Existem diversas vantagens em utilizar estas tintas como ganho em tempo e em velocidade de operações, e menor gasto de combustível, pois a bioincrustação aumenta a rugosidade da superfície e diminui a hidrodinâmica das embarcações. Em geral, a maioria destas tintas contém biocidas que evitam que os organismos incrustantes consigam se estabelecer sobre a superfície das embarcações. Esses biocidas por sua vez, acabam por serem liberados das pinturas provocando danos aos ecossistemas, como, por exemplo, o imposex, que é a masculinização de fêmeas de moluscos gastrópodes, um problema de disrupção endócrina causada pelo tributilestanho (TBT). Novos biocidas surgiram no mercado global após o banimento do TBT como alternativas menos danosas, porém muitos estudos comprovam efeitos prejudiciais a biodiversidade aquática, principalmente quando combinados. No Brasil, as regulamentações ambientais que dizem respeito às tintas anti-incrustantes são a Norman 23 da Marinha do Brasil, que estabelece as diretrizes para os sistemas anti-incrustantes, e a Resolução Conama 357, que estabelece os padrões de qualidade de águas. Esses dois documentos estão relacionados apenas ao uso do TBT, que foi banido em 2008. Em relação aos novos biocidas não existe nada neste aspecto, embora a Normam 23 tenha opção de incluir outros biocidas, caso necessário. O presente estudo tem por objetivo ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The use of some kind of antifouling protection is mandatory for ships and submerged structures. This use has many advantages, such as time gains in trips and general operations due to higher attainable speeds and reduced fuel consumption, as biofouling increases hull roughness and reduces hydrodynamic performance of the vessel. In a general way, most of these paints include biocides, to avoid the organism fixation in the vessel’s hull surface. However, these biocides cause environmental problems such as imposex, which causes masculinization of female marine gastropods, an endocrine disruption problem caused by tributyltin (TBT). New biocides were introduced in the global market after the TBT banning as less harmfull alternatives, but many studies have shown that these also could cause damage to marine ecosystems, and particularly when combined. In Brazil, environmental regulations on antifouling paints are: Normam 23, from the Brazilian Navy, which regulates application of marine antifouling systems, and Resolution 357 from CONAMA (Brazilian National Environment Council), which establish the water quality parameters. Both documents include only organotins (Normam 23) or specifically TBT (Res. 357), forbidden as antifouling since 2008. The new antifouling biocides are not discussed or regulated in these regulatory instances, while Normam 23 have the possibility of upgrade for including other biocides if required. This study is aimed at an evaluation of the possible risks to ma... (Complete abstract click electronic access below) / Doutor

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