Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 20 of 74 for “"toxicity tests"”.
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The development of functional in vitro toxicity tests
In vitro toxicity tests which detect evidence of the formation of reactive metabolites have previously relied upon cell death as a toxicity end point. Therefore these tests determine cytotoxicity in terms of quantitative changes in specified cell functions. In the studies involving the CaC0-2 cell …
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Multispecies toxicity tests using indigenous organisms: predicting the effects of hazardous materials in streams
… and protozoans to responses observed in acute tests with Daphnia magna, Ceriodaphnia dubia and Pimephales promelas and chronic survival and reproductive tests with C. dubia The predictive utility of these various tests was then evaluated against observed effects in the receiving stream. The …
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The use of Chironomus riparius (Diptera: Chironomidae) in benthic toxicity tests and its response to selenium
… to: 1. Develop a method for performing acute toxicity tests using Chironomus riparius. 2. Establish relationships between dry mass and selenium content, and between dry mass and selenium body burden. 3. Determine whether bioaccumulation or bioconcentration contributed more to the selenium …
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The effects of acid and water hardness on bluegill embryo-larvae determined by laboratory and on-site toxicity tests
… was compared in five day laboratory toxiclty tests. Embryo-larval bluegill were exposed to pH levels ranging from 3.8 to 7.0 in soft water and from 3.8 to 8.0 in hard water. An on-site toxicity test, using lake water (3.4 mg/L CaCO₃) adjusted to pH levels ranging from 3.5 to 7.3, was conducted …
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Laboratory and field studies of cadmium effects on Hyalella azteca in effluent dominated systems.
Laboratory single-species toxicity tests are used to assess the effects of contaminants on aquatic biota. Questions remain as to how accurately these controlled toxicity tests predict sitespecific bioavailability and effects of metals. Concurrent 42-day Hyalella azteca exposures were performed with …
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Comparative Toxicity of Eight Model Substances to the Sediment Dwelling Invertebrates Lumbriculus variegatus and Chironomus riparius
Existing ecotoxicity data for chemicals vary to a high extent between the environmental compartments water and sediment, since the evaluation of contaminants has historically focused on water exposition. Many anthropogenic chemicals and waste materials, including toxic organic and inorganic …
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Investigation into three potential modifying factors in larval fathead minnow (Pimephales promelas) growth and survival
… of larval fish to toxicants in subchronic toxicity tests may be modified by events and stressors not associated with the toxicants themselves. In the following work, three potential modifying factors related to larval fish growth, survival, and response to toxicant stress were investigated. …
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An Evaluation of Coating Material Dependent Toxicity of Silver Nanoparticles
… types of coating materials may exhibit different toxicity effects. The study evaluated coating material dependent toxicity by selecting 3 types of AgNP synthesis methods with different coating materials (citrate, polyvinyl pyrrolidone, and branched polyethyleneimine, coated AgNPs as citrate-AgNPs, …
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Evaluation of a mitochondrial test for the determination of chemical toxicity
… respiratory parameters as a short-term toxicity test was investigated. Mitochondrial fractions were exposed to six concentrations of five chlorophenols. Respiratory parameters were measured and compared to control experiments. The toxicity of the chlorophenos, measured by the 50% …
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Chronic toxicity of phthalates, biphenol and a Canadian bottled water stored under different light regimes using the Cnidarian Hydra Viridissima©
… to bottled water and plastic leachates caused toxicity to the freshwater Cnidarian Hydra viridissima (green hydra). Three chemicals used in the production of polycarbonate and polyethylene plastics, bisphenol A (BPA) and two phthalate esters: dibutyl phthalate (DBP) and bis (2- ethylhexyl) …
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A comparison of techniques for estimating the hazard of chemicals in the aquatic environment
… aquatic ecosystems were derived from laboratory tests conducted at two levels of the biological hierarchy. A population level estimate was derived from single species toxicity tests and a community level estimate was derived from laboratory tests on microbial communities. Estimates were compared …
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Effects of Methanol, Atrazine, and Copper on the Ultrastructure of Pseudokirchneriella Subcapitata (Selenastrum Capricornutum).
The toxicity of methanol, atrazine, and copper to Pseudokirchneriella subcapitata (Korshikov) Hindák historically referred to as Selenastrum capricornutum Printz were determined following 96 hrs growth in a modified Goram's growth media. Methanol and atrazine inhibited fluorescence readings in the …
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Negative phototaxis of mosquito larvae as a potential tool in the rapid biological monitoring of aquatic wastes (Diptera: Culicidae)
A little-known approach to toxicity testing--based on negative phototaxis of larval <u>Aedes aegypti</u>--was investigated as a contribution to the search for rapid methods applicable to the field of water pollution control. Zinc and copper were the toxicants tested. All tests were conducted with a …
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Ecotoxicology and ecophysiology of mysids, with special reference to copper toxicity in Praunus flexuosus
Toxicity of dissolved copper was examined in a common coastal mysid population {<i>Praunusflexuosus</i>}. The life cycle and ecophysiology were studied under natural conditions throughout the year, and responses to dissolved copper were determined in the laboratory. Pronounced and ontogenic …
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Physicochemical and biological treatment of a textile dyeing and finishing wastewater
… often high in color, organic matter, metals and toxicity. Treatment is usually required before discharge into a sewer or body of water. Pretreatment often consists of chemical coagulation to remove color and solid matter. Aerobic biological treatment is incorporated to remove degradable organic …
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Potential Coal Slurry Toxicity to Laboratory and Field Test Organisms in the Clinch River Watershed and the Ecotoxicological Recovery of Two Remediated Acid Mine Drainage Streams in the Powell River Watershed, Virginia
… Virginia were evaluated for acute and chronic toxicity using field and laboratory tests. The results of the study suggested that the primary effluent from the coal preparation facility had acute and chronic toxicity; however, the settling pond system utilized at this plant mitigated the impacts …
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The effects of select non-steroidal anti-inflammatory drugs on green and brown hydra
… several NSAIDs were assessed for their potential toxicity to Hydra. Chronic toxicity was evaluated using three NSAIDs on two different species of Hydra, Hydra viridissima and Hydra littoralis. Several negative correlations were observed between ibuprofen, naproxen, diclofenac toxicity and select …
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Quantifying the presence of current-use insecticides and toxicity of sediments in urban residential watersheds in central Texas.
… streams in central Texas. Additionally, the toxicity of these sediments to Hyalella azteca was evaluated. Sediment samples were collected from several sites in urban streams over the course of a pesticide application season. The sediments were extracted and analyzed using a Varian 2100 gas …
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Evaluation of the potential environmental toxic effects of a nylon fibers additive
… disposal system. An assessment of the toxicity of the antimicrobial additive was made using conventional greenhouse studies. This assessment was compared to the results obtained from three short-term toxicity tests performed on the same set of solutions. The short-term tests used were a …
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