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Toxicology Commons

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Full-Text Articles in Toxicology

Bioaccumulation Of Polychlorinated Biphenyl Compounds And Mercury In A Mining Impacted Aquatic Ecosystem, Michelle Bollini Jan 2023

Bioaccumulation Of Polychlorinated Biphenyl Compounds And Mercury In A Mining Impacted Aquatic Ecosystem, Michelle Bollini

Dissertations, Master's Theses and Master's Reports

The Keweenaw area continues to be influenced by the century of copper mining that ended nearly 50 years ago. This project is focused on Torch Lake, an aquatic ecosystem that has been heavily impacted by mining waste disposal. The watershed has been impaired by mine discharge and tailings, smelter and smokestack plumes, and poor waste disposal practices. The lake is listed as a Great Lakes Area of Concern with beneficial use impairments of restrictions on fish consumption and a degraded benthic community. Polychlorinated biphenyl compounds (PCBs) and methylmercury (MeHg) are persistent, bioaccumulative, and toxic substances (PBTs). These contaminants pose threats …


Avian Haemosporidian Blood Parasite Diversity, Prevalence, And Distribution In Michigan’S Western Upper Peninsula, Maria M. Ferrer Jan 2022

Avian Haemosporidian Blood Parasite Diversity, Prevalence, And Distribution In Michigan’S Western Upper Peninsula, Maria M. Ferrer

Dissertations, Master's Theses and Master's Reports

Avian haemosporidian parasites, known as avian malaria (phylum Apicomplexa) can diminish an individual bird’s fitness by causing parasitemia, anemia, and reduced survival. Climate change is predicted to increase the spread of malarial parasites into more northerly latitudes where little is known about community compositions of these parasites. I assessed the prevalence and diversity of haemosporidian parasites in the first-ever community-level sampling of malaria in songbirds across the western Upper Peninsula of Michigan. In total, 179 blood samples were collected from birds representing 17 species, at five locations in the Upper Peninsula, including a mature forest, an early successional forest, and …


The Effect Of Seasonality On Yellow Perch Ecology And Ecotoxicology Within Lake Manganese, Bailey Duxbury Jan 2020

The Effect Of Seasonality On Yellow Perch Ecology And Ecotoxicology Within Lake Manganese, Bailey Duxbury

Dissertations, Master's Theses and Master's Reports

Seasonality is a consistent component of aquatic ecosystems yet most fish biological and ecotoxicological studies commonly employ field sampling protocols focused during the warm open water season with minimal emphasis placed on winter sampling, especially for north-temperate latitude ecosystems. Such strategies limit our understanding of poikilotherm biology and ecology during the overwintering seasons. Here, I investigated seasonal changes in yellow perch (Perca flavescens) biology, ecology and ecotoxicology over a one-year period in Lake Manganese. Significant seasonality was observed for metrics including fish energy densities (kJ/g), gonadosomatic indices, whole-body lipid contents, and carbon stable isotope values (δ13C). …


Heavy Metal Accumulation In Urban Soil: A Phytoextraction Method Review, Diane M. Nelson Jan 2016

Heavy Metal Accumulation In Urban Soil: A Phytoextraction Method Review, Diane M. Nelson

Dissertations, Master's Theses and Master's Reports

Lead (Pb), cadmium (Cd), and arsenic (As) are three common non-essential heavy metals found in urban soils and can prove toxic to animals, humans, and some plants at low concentrations. The main exposure pathways of heavy metals in humans are through ingestion and inhalation of soil particles and ingestion of contaminated food. When dealing with contaminated soil in urban environments, activities like urban gardening can increase the likelihood of these exposure pathways, so heavy metal toxicity from contaminated soil can become a greater risk with the increased interest in urban agriculture. The US EPA created target concentrations for these heavy …


The Mechanisms Of Α-Amanitin Resistance In The Fruit Fly Drosophila Melanogaster, Chelsea L. Mitchell Jan 2015

The Mechanisms Of Α-Amanitin Resistance In The Fruit Fly Drosophila Melanogaster, Chelsea L. Mitchell

Dissertations, Master's Theses and Master's Reports

Insect pesticide resistance has become a costly problem in the US. To make things more problematic, resistance to one pesticide is often associated with cross-resistance to other toxins, including pesticides that have not yet even been developed. In this study, we investigated a possible type of cross-resistance in the model fruit fly Drosophila melanogaster, some stocks of which are resistant to the very potent mushroom toxin α-amanitin. Because α-amanitin is solely produced by mushrooms, and because D. melanogaster does not feed on mushrooms in nature, the fruit flies should not be resistant to this toxin. In order to understand …