Toxicology Commons^™

Using A Toxic Aging Coin To Assess Hexavalent Chromium Neurotoxicity: Impact Of Cr(Vi) On The Blood-Brain Barrier, Liam Buchanan

College of Arts & Sciences Senior Theses

The US population faces simultaneous public health threats from both aging and environmental pollutants. Chief among these is hexavalent chromium [Cr(VI)], whose toxic effects in peripheral tissues are well-established but its effects on the brain are still understudied. Following previous results indicating hippocampal metals dyshomeostasis after Cr(VI) exposure, we aim to assess Cr(VI)’s impact on the blood-brain barrier (BBB), a key structure for brain protection. We exposed young, middle-aged, and geriatric rats of both sexes to low levels of Cr(VI) in their drinking water for 90 days, after which we used immunofluorescence and confocal microscopy to analyze tissues for evidence …

Acute Effects Of The Psychoactive Pollutant Fluoxetine On The Antipredator Behavior Of The Gulf Killifish (Fundulus Grandis), Semyra Reus

Honors Theses

Pharmaceutical contaminants are increasingly prevalent in aquatic environments, yet their sublethal effects on ecologically relevant behaviors remain poorly understood, particularly in estuarine systems. Selective serotonin reuptake inhibitors (SSRIs), such as fluoxetine, are of particular concern due to the conserved role of serotonin in regulating behavior across vertebrates. Here, we investigated how acute exposure to environmentally relevant concentrations of fluoxetine influences anti-predator behavior in Gulf killifish (Fundulus grandis), a key estuarine fish commonly found in saltmarsh habitats. Killifish were exposed to control (0 ng/L), low (17.8 ng/L), and high (596 ng/L) fluoxetine concentrations and subsequently tested in the presence …

Histological Analysis Of Six Atlantic Scleractinian Coral Species Exposed To Three Hydrocarbons, 1-Methylnapthalene, Phenanthrene, And Toluene, Jalyn R. Lee

All HCAS Student Capstones, Theses, and Dissertations

Coral reefs are biologically diverse marine ecosystems that provide numerous goods and ecosystem services. These sessile organisms are vulnerable to anthropogenic impacts, habitat degradation, climate change, and pollution, particularly Petroleum hydrocarbon contamination. Previous research has characterized coral species' sensitivity to hydrocarbons, using a continuous passive dosing system, but the specific histological impacts of petroleum hydrocarbons remain underexplored. This study investigates the histological effects of three petroleum hydrocarbons, 1-methylnaphthalene, phenanthrene, and toluene, on six Atlantic scleractinian coral species: Acropora cervicornis, Porites astreoides, Porites divaricata, Solenastrea bournoni, Stephanocoenia intersepta, and Siderastrea siderea. Coral fragments were exposed to species-specific hydrocarbon concentrations, and …

False Halos: A Case Of Digoxin Poisoning, Usman Nazeer, Sarita Thanedar, Jacob Sanderson, Gongkai Liu, Hitesh Gidwani

Central & West Texas and San Antonio GME Research Day 2026

No abstract provided.

Β-Glucan Mitigates Valproic Acid-Induced Hepatorenal Toxicity In Rats, Maha Mohammad Almutairi, Hussein Mohammad Ali, Mohamed Abdelbakky, Ahmad Hamad Alhowail

Saudi Toxicology Journal

Valproic acid (VPA) is a common medication used to treat epilepsy, known for its broad-spectrum efficacy but also associated with hepatotoxicity and metabolic disturbances. β-glucan, a natural polysaccharide with hepatoprotective properties, may mitigate druginduced liver damage. The study sought to assess hepatorenal toxicity of VPA and investigate the potential protective and therapeutic effects of β-glucan. Forty male rats were randomly distributed into four groups. The treated group received VPA (500 mg/kg), β-glucan (50 mg/kg), or combinations for 14–21 days via intraperitoneal injection. Serum biochemical parameters (ALT, AST, ALP, urea, creatinine, lipids) were measured. Histopathological evaluation of hepatic tissue was performed. …

Effects Of Tubulin-Binding Medications On Microplastic Uptake And Cyotoskeletal Functionality Across Diverse Cell Types, Alejandra D. Favela Santos

Posters - 2026

• Microtubules are composed of of a- and b- tubulin heterodimers, vital for cell structure, shape, and intracellular transport • Microtubules are also useful as they separate chromosomes during cell division • Microplastics (< 5 mm) are considered a health threat and have been found throughout the whole body (1) o In several studies, microplastics have been correlated to higher rates cardiorespiratory issues, endocrine disruption, and cancer (1) • Tubulin-binding medications are widely used as chemotherapeutic agents as they are known for disrupting cell division and targeting tubulin (2,3) o In this study, these medications were used to determine whether microtubules play a role in microplastic uptake § Colchicine typically binds to tubulins and arrests polymerization and growth § Nocodazole disrupts polymerization and prevents spindle formation § Vinblastine inhibits microtubule assembly and disruptions miotic spindle formation.

• The purpose of this study was to determine if different concentrations of tubulin-binding medications affect microplastic uptake o C2C12, RAW 264.7, and MOVAS cell lines were used to evaluate whether these changes are cell type specific 

If microtubule dynamics are disrupted, microplastic uptake can be affect in a concentration-dependent and cell type- specific manner.

Microplastic-Mediated Delivery Of Di-Butyl Phthalate Alters C. Elegans Lifespan And Reproductive Fidelity, Chiara Angelyn Maldonado

Presentations - 2026

•The challenge: microplastic contamination •The question: How do microplastics and chemical contaminants affect living organisms? •The follow-up: What’s next!

Polylactic Acid (Pla) Microplastic Toxicity In C. Elegans, Maria Gamez, Dana Farley, Chiara Maldonado, David Mares

Posters - 2026

• Microplastics (MPs, > 5 mm1) are an environmental pollutant that pose health risks to humans. • Primary MPs are created for direct use or plastic stocks, and secondary MPs are created when plastics in the environment break down over time. • Microplastic exposure can cause oxidative stress, metabolic disorders, immune responses, neurotoxicity, and reproductive issues2-3. • Polylactic Acid (PLA) is a biodegradable plastic used in everyday items, such as food packaging, and as a polymer in 3D printing. • PLA exposure to fish causes organ damage5 and C. elegans exposure to primary PLA MPs and UV-aged MPs reduced reproduction6-7 . …

Take A Hit? Take A Hit: Quantifying Cell Death In E-Cigarette Exposed Bronchial Epithelial Cells Following Cards Toxin Treatment, Truman Havrda, Hannah Jiron, Sierra Trevino

Posters - 2026

The rapid rise of e-cigarette use among young adults has created a significant public health challenge, as the popularity of "vaping" has grown faster than our understanding of its long term cellular consequences. Current research indicates that e-cigarette vapor (ECV) induce high levels of oxidative stress and impair the lungs' ability to clear bacterial pathogens. Furthermore, ECV exposure upregulates specific receptors on the surface of airway cells, essentially making it easier for bacteria to adhere to and infect the lungs. While we know that both e-liquids and vapor trigger inflammatory responses and cytotoxicity, there is limited data on how these …

"I Need Help!": Can Ashwagandha Reduce Inflammation-Driven Oxidative Stress Without Inducing Cytotoxicity In Macrophages?, Caitlyn Pinaga

Posters - 2026

Ashwagandha has been shown to reduce inflammation in humans by lowering pro-inflammatory cytokines and oxidative stress markers, helping regulate immune responses. It is commonly used to support conditions linked to chronic inflammation, such as stress-related disorders, arthritis, and metabolic imbalance. THP-1 macrophages are a part of the body's immune response to inflammation. While they produce a lot of different responses to inflammation, one of them is the production of Reactive Oxygen Species (ROS). N-acetylcysteine (NAC) is established to be a powerful antioxidant and is used as a positive control. My study aims to understand how ashwagandha, a popular supplement, affects …

Muscular Degeneration In Caenorhabditis Elegans By Microplastic And Chemical Exposure Through Locomotion Analysis, Juan Pablo Olvera Rodriguez, Angelica Cue-Leon, David Mares

Posters - 2026

We use Caenorhabditis elegans (C. elegans) as a model organism to investigate the effects of microplastic and chemical exposure on muscle structure and function.

• Microplastics (MP) are pieces of plastic less than 5 μm, and Nanoplastics (NP) are less than 1 μm. Microplastics are man-made pollutants and have been found in the environment and in the food and water sources, including drinks from plastic bottles (Hu, 2020). • Our work relates environmental contamination to potential biological consequences at the muscular level, providing insight into how pollutants may contribute to degenerative damage.

• Polystyrene (PS) MPs alone and combined with …

An Investigation In The Physiological Effect Of Microplastic And Chemical Mixtures In The Body Length Of C. Elegans, Gregory Guantos, David M. Mares, Jennifer C. Harr Phd

Posters - 2026

• Microplastics (MP) are pieces of plastic less than 5 micrometers (mm). Microplastics are found in our environment and have even been found in the food humans consume, including in drinks from plastic bottles (Hu 2020).

• Di-butyl Phthalate (DBP) is a chemical known as a plasticizer commonly used in PVC applications, ink, fragrances, and adhesives

• Di-butyl Phthalate has been found to have negative effects on the physiological length of C. elegans (Xiyan 2018)

• Microplastics have similarly been found to decrease the physiological length of C. elegans (Schöpfer 2020)

• The combined effects of MPs and DBP include …

Imidacloprid Effects On The Survival And Cutaneous Microbiome Of Northern Leopard Frogs, Evelyn Margaret Osterloo

Honors Thesis

Amphibians are experiencing population declines due to habitat loss, climate change, and diseases, particularly chytridiomycosis caused by the fungus Batrachochytrium dendrobatidis. Protection from this fungal infection stems from the cutaneous microbiome. Pesticides have been shown to affect amphibians in a variety of ways, including reducing survival, locomotor performance, and accumulation in body tissues. Pesticides may also lead to changes in the cutaneous microbiome affecting amphibians who rely on these organisms as an anti-Bd defense mechanism. To investigate the effect of imidacloprid, a neonicotinoid insecticide, Northern Leopard frogs (Lithobates pipiens) were subjected to sublethal concentrations (control = …

Metabolomics In Precision Medicine: Application And Prospect In Cancer Research, Ming-Shi Shiao

Journal of Food and Drug Analysis

Metabolomics is the most recent and final discipline among the post-genomic, multiomics fields. It encompasses key technologies in systems biology, providing an overview of low-molecular-weight metabolites while examining disturbances to offer pathophysiological explanations. The two key analytical tools in metabolomics are nuclear magnetic resonance spectroscopy and mass spectrometry, which includes gas chromatography-mass spectrometry and liquid chromatography-mass spectrometry. Metabolomic research relies on a three-stage data generation process: the first stage involves precise analytical chemistry to produce data; the second stage employs multivariate statistical analysis; and the last stage uses big data as a reference for comparison to establish biochemical, metabolic, and …

Mass Spectrometry-Based Metabolomics For Studying Gut Microbiota-Derived Metabolites In Biological Samples, Ya-Ting Lin, Huai-Hsuan Chiu, Chih-Ning Cheng, Ching-Hua Kuo

Journal of Food and Drug Analysis

Gut microbiota produces a wide range of metabolites and plays a critical role in maintaining host health. Dysregulation of these metabolites can influence host metabolism through systemic circulation, contributing to the development of various diseases, including immunological, neurological and cancer-related disorders. Chromatography coupled with mass spectrometry (MS) has emerged as a powerful analytical approach, offering high sensitivity and resolution for studying gut microbiota-related metabolites. This review provides a comprehensive overview of chromatographic MS-based methods applied to the study of the gut microbial metabolome. We summarize strategies for sample collection, storage, and preparation of commonly analyzed sample types, including feces, plasma/serum, …

Special Issue: Analytical Technologies In Metabolomics: Applications And Future Prospects, Sung-Fang Chen

Journal of Food and Drug Analysis

No abstract for this article type.

Comparison Of Heavy Metal Accumulation In Soil And Wood Core Within Tallassee And Tuskegee, Alabama, Alicia R. Wilson, Brianna Smith, Latricia Miller, Rashidah Farid

Professional Agricultural Workers Journal

Heavy metals are natural components of the environment and can be relatively non-impactful in low concentrations. However, high concentrations of heavy metal toxicity can result in air, water, and soil contamination that adversely impacts environmental, human, and wildlife health. This study focuses on detecting the presence of heavy metals in soil, Loblolly Pine tree bark, and wood core samples from sites near a landfill in the Tallassee, Alabama, community and a post-agricultural site in Tuskegee, Alabama. It has been hypothesized that heavy metals are present in soil, tree bark, and the tree’s wood core from sampling sites. Samples were taken …

Seafood, Mercury, And Human Health In Coastal South Carolina: Findings From A Community-Based Study, Russell Fielding, Julia Saltzman, Rylee-Jade Bean, Jenna Monroe, Theodore R. Them Ii

Honors College Faculty Publications

Mercury (Hg), an environmental pollutant, can harm human health. Seafood consumption is a major way that people are exposed to Hg and the analysis of human hair is a standard method to measure Hg exposure. This community-based study identified demographic and dietary factors associated with elevated Hg concentrations and health outcomes of individuals with elevated Hg concentrations throughout two coastal South Carolina (SC) counties. We collected hair samples (n = 85) at local barbershops and salons; participants completed an online survey with questions on demographics, diet, and health histories; and we analyzed hair samples using a DMA-80. Between 4.9–8.4% of …

Trophic Structure And Mercury Bioaccumulation In Walleye And Yellow Perch In The Upper And Lower Red Lake Basins, Marissa Pribyl

Biology Graduate Theses

Mercury is a persistent global contaminant that biomagnifies through aquatic food webs, with dietary and environmental factors serving as the primary drivers of accumulation in fishes. Trophic structure and methylmercury dynamics in Walleye (ogaa; Sander vitreus) and Yellow Perch (asaawens; Perca flavescens) were investigated in the Upper and Lower Red Lake basins in Red Lake, Minnesota, during 2024-2025. Diets of Walleye and Yellow Perch were assessed through stomach dissections, and tissue samples from both species were analyzed for total mercury concentrations. Additional analyses included shiners (gigoozens; Notropis spp., Hudsonius spp.) along with a variety of freshwater fish and …

Conditioned Feed Aversion As A Means Of Conditioning Livestock To Avoid Consuming Toxic Plants Growing In South Africa : An Overview, Leendert D. Snyman, Frederick D. Provenza

Poisonous Plant Research (PPR)

Significant economic losses to the livestock industry are caused by the ingestion of toxic plants in South Africa, among which the most dangerous ones are Moraea pallida (geeltulp), Urginea/Drimea sanguinea (rooislangkop), Senecio latifolius (Staggers Ragwort), and Geigeria ornativa (vermeerbos). Conditioned feed aversion is a potential means to address this issue. Treating animals with an aversive substance along with an extract of the sensory characteristics of a specific plant conditions animals to avoid the plant. Geigeria ornativa, unlike the other three plants, is non-aversive. Following treatment for aversion, the induced aversion fades with time and eventually breaks down. Continuous exposure …