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Full-Text Articles in Toxicology

The Influence Of Acidification And Copper Exposure On Copper Accumulation And Anti-Oxidant Enzyme Responses In The Pond Snail, Lymnaea Stagnalis, Gretchen K. Bielmyer-Fraser, Francis Alip, Ruth Adeyemi, Nolan Carney, Fasinia Santiago, Kyla Siemen, Kiley Donaghy Apr 2020

The Influence Of Acidification And Copper Exposure On Copper Accumulation And Anti-Oxidant Enzyme Responses In The Pond Snail, Lymnaea Stagnalis, Gretchen K. Bielmyer-Fraser, Francis Alip, Ruth Adeyemi, Nolan Carney, Fasinia Santiago, Kyla Siemen, Kiley Donaghy

Georgia Journal of Science

Atmospheric carbon dioxide is rising at an accelerated rated due to increased anthropogenic activities. Metals have also been a noted problem; however, little research has addressed combined exposure of both pollutants to sensitive, calcifying organisms in freshwater habitats. This study examined copper accumulation (over 7 d) and activity of the antioxidant enzymes, catalase and glutathione peroxidase (over 2 d), in the freshwater common pond snail, Lymnaea stagnalis, after exposure to ambient and increased (2000 µatm) CO2 and copper (control, 5, and 20 µg/L). Results demonstrated increased copper accumulation in soft tissue of snails exposed to copper; however, exposure to …


The Exploration Of Nanotoxicological Copper And Interspecific Saccharomyces Hybrids, Matthew Joseph Winans Phd Jan 2020

The Exploration Of Nanotoxicological Copper And Interspecific Saccharomyces Hybrids, Matthew Joseph Winans Phd

Graduate Theses, Dissertations, and Problem Reports

Nanotechnology takes advantage of cellular biology’s natural nanoscale operations by interacting with biomolecules differently than soluble or bulk materials, often altering normal cellular processes such as metabolism or growth. To gain a better understanding of how copper nanoparticles hybridized on cellulose fibers called carboxymethyl cellulose (CMC) affected growth of Saccharomyces cerevisiae, the mechanisms of toxicity were explored. Multiple methodologies covering genetics, proteomics, metallomics, and metabolomics were used during this investigation. The work that lead to this dissertation discovered that these cellulosic copper nanoparticles had a unique toxicity compared to copper. Further investigation suggested a possible ionic or molecular mimicry …


The Effects Of Copper Exposure On Fish Locomotion And Predator-Prey Interactions, Tiffany N. Yanez Dec 2018

The Effects Of Copper Exposure On Fish Locomotion And Predator-Prey Interactions, Tiffany N. Yanez

FIU Electronic Theses and Dissertations

This study determined the effects of the copper water quality criterion (WQC) by the EPA on [1] swimming performance and [2] predator-prey interactions of the Sailfin Molly, across a salinity gradient. Fish acclimated to FW (0 ppt) and 8-ppt saltwater were exposed to 11.3 and 8.44 µg/L Cu for 96 h, respectively. At the end of the exposures, fish swimming performance was determined by using the critical swimming speed, Ucrit, the speed at which a fish cannot longer maintain position in the water column. Ucritwas then measured again after a 4-week depuration period to determine if …


Lead, Copper, And Iron In University Tap Water, Alison Mclendon May 2018

Lead, Copper, And Iron In University Tap Water, Alison Mclendon

Honors Theses

This study observed concentrations of lead, copper, and iron in university tap water over an eight-week span during and between the summer and fall semesters. First draw and 30s flush samples were taken after overnight stagnation from the Honor House, College Hall, J. B. George Building, and International Center bathrooms and analyzed with an inductively-coupled plasma mass spectrometer (ICPMS). There was no obvious correlation between time in the semester and metal concentrations. Relative iron levels rose and fell at the same time in all buildings, but there was little correlation between buildings for lead and copper concentrations. The Honor House …


Examining Mechanism Of Toxicity Of Copper Oxide Nanoparticles To Saccharomyces Cerevisiae And Caenorhabditis Elegans, Michael Joseph Mashock Apr 2016

Examining Mechanism Of Toxicity Of Copper Oxide Nanoparticles To Saccharomyces Cerevisiae And Caenorhabditis Elegans, Michael Joseph Mashock

Dissertations (1934 -)

Copper oxide nanoparticles (CuO NPs) are an up and coming technology increasingly being used in industrial and consumer applications and thus may pose risk to humans and the environment. In the present study, the toxic effects of CuO NPs were studied with two model organisms Saccharomyces cerevisiae and Caenorhabditis elegans. The role of released Cu ions during dissolution of CuO NPs in growth media were studied with freshly suspended, aged NPs, and the released Cu2+ fraction. Exposures to the different Cu treatments showed significant inhibition of S. cerevisiae cellular metabolic activity. Inhibition from the NPs was inversely proportional to size …


The Sublethal Physiological Effects Of Exposure To Copper And Silver Mixtures On Rainbow Trout (Oncorhynchus Mykiss), Wesley Truong Jan 2016

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 …


Nickel And Copper Mixture Toxicity To Daphnia In Soft Water, Prachi Deshpande Jan 2016

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 …


Effects Of Salinity And Dissolved Organic Matter On Cu Toxicity To Americamysis Bahia In Estuarine Environments, Rabia Nasir Jan 2014

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 Jan 2013

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 …


Lipid Peroxides And Glutathione Status In Human Progenitor Mononuclear (U937) Cells Following Exposure To Low Doses Of Nickel And Copper, William Y. Boadi, Shalandus Harris, Justin B. Anderson, Samuel E. Adunyah May 2012

Lipid Peroxides And Glutathione Status In Human Progenitor Mononuclear (U937) Cells Following Exposure To Low Doses Of Nickel And Copper, William Y. Boadi, Shalandus Harris, Justin B. Anderson, Samuel E. Adunyah

Chemistry Faculty Research

Effects of Cu2+, Ni2+ or Cu2+ + Ni2+ on lipid peroxide and glutathione (GSH) levels in U937 cells were investigated. Cells were treated with 0, 5, 10, and 20 µM of Cu2+ and/or Ni2+ and H2O2 (0.01 mM) and incubated for 24 hours at 37°C. Lipid peroxides were measured by the thiobarbituric acid assay (TBA). GSH intracellular levels were assayed by the GSH assay kit from EMD/Calbiochem (San Diego, California, USA). Cu2+ or Ni2+ significantly (P < 0.01) increased lipid peroxides in a dose-dependent manner, compared to controls. The effect was more pronounced for Cu2+, compared to the Ni2+-treated samples. Cu2+ + Ni2+ increased lipid peroxides in a significant (P < 0.001), dose-dependent manner, compared to Cu2+ or Ni2+ alone (i.e., ratio of 2.5:1-fold for combined versus single treatments, respectively). Cu2+ or Ni2+ significantly decreased GSH levels in U937 cells, with the effect being pronounced for Cu2+. Cu2+ + Ni2+ metal ions significantly (P < 0.001) depleted cells of GSH in a dose-dependent manner. Ethylene diamine tetraacetic acid (EDTA) at 50 or 100 µM moderately reduced the Cu2+- or Ni2+-induced effects on GSH levels. Interestingly, GSH levels generally decreased to half (except for the combined metal dose of 20 µM at 100 µM EDTA) of its level at the highest metal concentration tested for both the single or combined treatments. In conclusion, multiple exposures of cells to metal ions may be lethal to cells, compared to their single treatments.