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Full-Text Articles in Toxicology
Nickel And Copper Mixture Toxicity To Daphnia In Soft Water, Prachi Deshpande
Nickel And Copper Mixture Toxicity To Daphnia In Soft Water, Prachi Deshpande
Theses and Dissertations (Comprehensive)
Industrially important metals, such as Cu and Ni, sometimes are present at elevated concentrations in lakes, including those in the Sudbury, ON region. Although they are essential metals, their divalent-cation state (Cu2+ and Ni2+) can be toxic at high concentrations in the water. The free-ion toxicity of each of these metals has been studied in isolation, but rarely as a mixture. The economic importance of Cu2+ and Ni2+ makes them essential to study in the context of mixture toxicity. The objectives were to: (1) determine Cu and Ni mixture toxicity to Daphnia through acute LC50 …
The Sublethal Physiological Effects Of Exposure To Copper And Silver Mixtures On Rainbow Trout (Oncorhynchus Mykiss), Wesley Truong
The Sublethal Physiological Effects Of Exposure To Copper And Silver Mixtures On Rainbow Trout (Oncorhynchus Mykiss), Wesley Truong
Theses and Dissertations (Comprehensive)
The mechanisms behind metal-metal interactions in freshwater environments are currently not well understood. Freshwater environments consist of many different types of metals, from those naturally present such as copper (Cu) and those that originate from anthropogenic sources like silver (Ag). Both Cu and Ag use apical sodium (Na+) channels for uptake into the gills of freshwater fish. In the gills, the mechanisms of Cu2+ and Ag+ toxicity appear to be similar to one another, which is by inhibiting Na+ /potassium (K+)- adenosine triphosphatase (NKA) and carbonic anhydrase (CA). Inhibition of NKA and CA …
Effects Of Salinity And Dissolved Organic Matter On Cu Toxicity To Americamysis Bahia In Estuarine Environments, Rabia Nasir
Effects Of Salinity And Dissolved Organic Matter On Cu Toxicity To Americamysis Bahia In Estuarine Environments, Rabia Nasir
Theses and Dissertations (Comprehensive)
As salinity increases the geochemical speciation of Cu is altered as a result of organic/inorganic complexation/competition. Such salinity changes may further challenge the osmoregulatory capabilities of euryhaline organisms. This chemical-biological interaction complicates the understanding of the impacts of Cu in estuarine waters. Dissolved organic matter (DOM) has been widely established to be an important modifier of Cu toxicity in freshwaters however its effectiveness in modulating Cu toxicity across the range of salinities that occur in estuarine conditions has not been studied in a systematic manner. Site to site differences in DOM quality with respect to the potential for toxicity mitigation …
Does Ecosystem Disturbance Alter The Capacity Of Dissolved Organic Matter To Mitigate The Impact Of Copper To Hyalella Azteca?, Kelly Livingstone
Does Ecosystem Disturbance Alter The Capacity Of Dissolved Organic Matter To Mitigate The Impact Of Copper To Hyalella Azteca?, Kelly Livingstone
Theses and Dissertations (Comprehensive)
The potential for aquatic ecosystem recovery as a result of dissolved organic matter (DOM) protecting against metal toxicity has become a significant area of research in environmental toxicology. It is a well-characterized relationship that DOM binds free metal ions in a concentration-dependant manner, making them unavailable for toxic action and a reduction in toxicity is seen. Less understood is source variability and how the upland terrestrial environment influences the protective quality of DOM. The aim of this study was to examine the influence of land disturbance (logging, fire, smelter emissions) on DOM quality by comparing the protective capacity of different …