Pharmacology, Toxicology and Environmental Health Commons^™

Health Goals For Perfluorinated Alkyl Substances (Pfas): A Review Of Branched Isomers, The Role Of Industrial Sources, And The Implications Of Pfas In Biosolids On End-Of-Life Disposal Methods, Katarina Schulz

Theses and Dissertations

Per- and polyfluorinated alkyl substances, or PFAS, have been used for over half a century, but have become an emerging contaminant of significant concern due to their newly found widespread occurrence and recalcitrance in the environment, their tendency to bioaccumulate, and the health effects now associated with a very low level of exposure. Many gaps in knowledge remain about the fate of these chemicals in the environment and the extent of their impacts on biota. This thesis aims to fill some of the recognized gaps in knowledge: differences between linear and branched isomers of PFAS, predicting the presence of PFAS …

An Investigation Into The Trophic Magnification Of Polychlorinated Biphenyls In The Lake Michigan Food Web, Philip Hurst

Theses and Dissertations

Polychlorinated biphenyls (PCBs) are a group of persistent organic pollutants known to contribute to several adverse health conditions in humans including cancers and a suite of liver diseases. While there exist 209 unique PCB congeners, the World Health Organization has identified 12 that pose the greatest health risk to humans due to these congeners’ functional similarity to dioxins, another notoriously toxic class of contaminants. Along with methylmercury, PCBs are the primary drivers behind fish consumption advisories in the Great Lakes. These guidelines are informed primarily by surveys of contaminants in freshwater biota. However, the proliferation of invasive species, such as …

Quantifying The Variability In Heavy Metal Concentrations In Produce Grown In Metals-Rich Soil, Harris Lowell Byers

Theses and Dissertations

Childhood Pb exposure is associated with a multitude of poor health outcomes. In food-insecure areas, growing fresh produce in residential backyard gardens is one option for parents; however, commonly grown crops are known to accumulate Pb in consumable tissues when grown in metals-rich soils. A variety of produce representing a continuum of consumable tissues were grown in soils collected from two residential vegetable gardens, a former metal foundry, and commercial topsoil purchased from a local hardware store. The concentrations of heavy metals in crop tissues were measured with custom wavelength dispersive X-ray Fluorescence (WD-XRF) spectroscopy and portable energy dispersive X-ray …

Development Of Cellular High Throughput Assays To Determine The Electrophysiological Profile Of Gaba(A) Receptor Modulators For Neurology And Immunology, Nina Yina Yuan

Theses and Dissertations

Gamma (γ) -aminobutyric acid (GABA) is the major inhibitory neurotransmitter found in

the mammalian central nervous system. Its effect stems from its ability to cause the opening of ion channels which causes an influx of negatively charged chloride ions or an efflux of positively charged potassium ions. This hyperpolarization of the neuron lowers the threshold for neuronal firing. This has an overall inhibitory effect on neurotransmission, decreasing the excitability of the neuron and diminishing the likelihood of a successful action potential occurring. There are two classes of GABA receptor: ligand-gated GABAA receptor (GABAAR) and metabotropic GABAB receptor (GABABR). The GABAAR …

Iodine-131: Measurement And Application Of A Novel Tracer In Lake Michigan, Michael Patrick Montenero

Theses and Dissertations

Iodine-131 is a short-lived (half-life=8.0233 days), gamma emitting, radiopharmaceutical that, when excreted by patients, enters aquatic systems via sewage effluent discharged from water reclamation facilities (WRFs). Here, I report on 131I activities in the nearshore of southwest Lake Michigan in the vicinity of Milwaukee, Wisconsin. This is the first report on 131I activity in any of the Great Lakes of North America.

The flux of 131I from Milwaukee’s two WRFs was monitored from July 2013 to December 2014. Mean discharge of 131I from the Jones Island WRF was (0.664 ± 0.012)×108 Bq d-1 (mean effluent 131I activity: ~0.25 Bq L-1; …

The Identification And Quantification Of Sewage Contamination In The Milwaukee Estuary, Hayley Templar

Theses and Dissertations

Sewage contamination from failing infrastructure and sewer overflows is a major environmental and human health concern in waterways, especially in urban communities bordering the Great Lakes such as Milwaukee, Wisconsin. Culture-based fecal indicator bacteria, such as Escherichia coli, enterococci, and fecal coliforms are traditionally used to indicate the presence of a human health risk due to fecal contamination. These indicators, however, fail to distinguish between sources of fecal contamination (human vs. non-human). Two human-specific fecal indicators, human Bacteroides and human Lachnospiraceae, were used to identify and quantify sewage contamination in the Milwaukee estuary, which discharges to Lake Michigan, as well …

Female Reproductive Impacts Of Dietary Methylmercury In Yellow Perch (Perca Flavescens) And Zebrafish (Danio Rerio), Abigail Rachael Debofsky

Theses and Dissertations

This study sought to evaluate the effects of dietary MeHg exposure on female teleost reproduction and phenotypically-anchor gene dysregulation in adult yellow perch (Perca flavescens) and zebrafish (Danio rerio) in order to establish relevant biomarkers relating exposure and subsequent reproductive effects. Yellow perch were used in the study for their socioeconomic importance within the Great Lakes basin, and their significance to the food web. Utilization of zebrafish allowed for a detailed analysis of the molecular effects of MeHg and established its relevance as a model for other fish species. MeHg exposures at environmentally relevant levels were done in zebrafish for …