Environmental Health Commons^™

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 . …

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 …

The Count Of White Blood Cells And Body Mass Index In The Smoker Population Of Tehsil, Dhirkot, District Bagh, Badra Younis, Muhammad Shahbaz, Ayesha Chattha, Anum Sadiq, Zakia Arif, Syeda Sabahat Fiaz

Journal of Bioresource Management

During this study, a total of 145 blood samples was collected from individuals aged between 16-65 years from tehsil Dhir Kot. Among them, 110 were smokers and 35 were non-smokers. Samples were taken in an evacuated container having Ethylene Diamine Tetra acetic Acid. Leucocyte count was done by using a hemocytometer and body mass index (BMI) was measured by using the formula BMI= kg/m². Among the smokers, 53 (48 %) individuals have normal BMI and out of the normal BMI, 47 (89 %) individuals have normal BMI and normal WBCs, but 3 (6 %) smokers had normal BMI …

Moderate-Temperature Hydrothermal Treatment Removes Detectable Dna And Antibiotic Resistance Genes From Municipal Sludge While Preserving Resource Value, R Sean Norman M.Sc., Ph.D., Mirza Isanovic, Gabrielle Kartzmark, Nicole Berge

Faculty Publications

Wastewater treatment plants (WWTPs) are key reservoirs of antibiotic resistance genes (ARGs), with municipal sludge containing high bacterial densities and diverse ARGs that may spread through land application. Hydrothermal treatment (HT) is a process that inactivates pathogens and stabilizes biomass, but its performance at moderate temperatures is less understood. We evaluated HT (100°C–250°C; 2–24 h) for degrading bacterial DNA and ARGs in dewatered municipal sludge. DNA was quantified by fluorometry, bacterial presence confirmed by 16S rRNA gene PCR, and ARGs profiled by qPCR targeting 84 clinically and environmentally relevant genes. HT up to 250°C produced modest carbon densification, high solids …

Moderate-Temperature Hydrothermal Treatment Removes Detectable Dna And Antibiotic Resistance Genes From Municipal Sludge While Preserving Resource Value, R. Sean Norman, Mirza Isanovic, Gabrielle Kartzmark, Nicole Berge

Faculty Publications

Wastewater treatment plants (WWTPs) are key reservoirs of antibiotic resistance genes (ARGs), with municipal sludge containing high bacterial densities and diverse ARGs that may spread through land application. Hydrothermal treatment (HT) is a process that inactivates pathogens and stabilizes biomass, but its performance at moderate temperatures is less understood. We evaluated HT (100°C–250°C; 2–24 h) for degrading bacterial DNA and ARGs in dewatered municipal sludge. DNA was quantified by fluorometry, bacterial presence confirmed by 16S rRNA gene PCR, and ARGs profiled by qPCR targeting 84 clinically and environmentally relevant genes. HT up to 250°C produced modest carbon densification, high solids …

Freshwater Quality For Recreation, Heather Nix, Masha Bokar

Forestry and Natural Resources

South Carolina has many water resources that provide tremendous opportunities for people to enjoy water-based recreational activities, such as swimming, boating, and fishing. Participation in these activities produces significant economic benefits and supports many jobs throughout the state. However, at times, water quality may be unsafe for immersion or skin contact due to high levels of pollutants, such as bacteria or cyanotoxins. It is important for people to be aware of potential concerns and understand methods for determining if a waterbody’s current conditions are likely to be safe for primary or secondary recreation.

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 …

Analysis Of Activated Carbon Fiber (Acf) As Particulate Filtration And Volatile Organic Compound (Voc) Media For The Development Of A Dual-Air Purifying Facepiece Respirator, Brie Mcmahan

ETDs from 2020-2029

Exposure to particulate matter (PM) and volatile organic compounds (VOCs) in occupational or public settings poses adverse health outcomes such as respiratory, cardiovascular, reproductive, neurological, carcinogenic morbidity and mortality. Many occupational settings expose workers to PM and VOC concurrently, yet most commercially available respirators are designed to address either particulates or vapors alone. This includes air-purifying respirators (APRs), powered air-purifying respirators (PAPRs), and filtering facepiece respirators (FFRs) with nuisance-level vapor protection, often limited by bulk, discomfort, high pressure drop, and misuse. We identified a need for alternative dual-exposure media and a respiratory protection device that is lighter, and more comfortable …

Temporal Variation Of Benthic Aquatic Macroinvertebrate Communities In Two Upland Intermittent Streams In The Boston Mountains, R. J. Mccollough, K. B. Hecke

Journal of the Arkansas Academy of Science

Benthic aquatic macroinvertebrates are some of the most highly used organisms for biomonitoring and assessing stream health. However, biomonitoring is often done in one season, potentially missing important taxa and inaccurately reflecting the community as well as stream health. In addition, while road crossing effects have also been extensively researched the last few decades, these studies are also often conducted in one season, likely misrepresenting the community structure and the overall effects of the road crossing. The highly known River Continuum Concept (RCC) is often applied to these benthic aquatic macroinvertebrate communities. This study aimed to examine aquatic macroinvertebrate communities …

When Words Flow Like Water: How The Enbridge Line 3 Pipeline Environmental Impact Statement Failed To Prevent Hydrogeologic Harm In Minnesota, Carly Gutzmann

Journal of Earth and Life Science

For the aquifers of Minnesota, the environmental impact statement (EIS) was a promise of protection that never left the page. An environmental impact statement is meant to be an aid in the decision making process in order to ensure that projects consider potential environmental harms that may occur. However, they are often used instead as another regulatory box to check, rather than as active considerations when planning. As such, a project plan can be flawed from the start—if project developers only consider environmental impacts after they have already put considerable time, effort, and funding into their project as-is, they may …

Spatial Temporal Modeling Of Infectious Disease Patterns In Texas, Robert E. Lashbrook

Earth & Environmental Sciences Theses

The Texas Department of State Health Services monitors numerous notifiable conditions statewide, including Campylobacter, Salmonella, Shiga toxin-producing Escherichia coli (STEC), Rabies, and West Nile virus (WNV). Given the substantial health, economic, and public health burden associated with these conditions, improving prediction is an important step toward reducing their overall impact. This study evaluated whether external demographic, social, climate, and environmental data could improve prediction of county-year disease activity across Texas. County level data was analyzed using supervised machine learning models, including linear regression, ridge regression, multilayer perceptron, random forest, XGBoost, as well as K-means clustering to identify broader …

Evaluating Sampling Strategies To Monitor Southern Fox Squirrel (Sciurus Niger Niger) Populations, Casey Robin Hitchens

Theses, Dissertations and Capstones

Reliable population monitoring is essential for evaluating wildlife translocations and informing conservation management, yet traditional monitoring approaches are often labor intensive and require prolonged sampling. This study evaluated marking techniques, survey methods, and population estimation approaches for monitoring a translocated population of southern fox squirrels (Sciurus niger niger) at Marine Corps Recruit Depot Parris Island, South Carolina, USA (MCRDPI). From January-June 2023, I conducted six live trapping and camera trapping sessions across five survey sites. I compared the performance of color-coded collars and tail shaves for individual identification and the recapture probability between live traps and camera traps. Logistic mixed-effects …

Lead Biosorption By Oceanobacillus Profundus Kbz 3-2: Strategies For Bioremediation Systems In Kabwe, Danielle S. Desmarteau

Scripps Senior Theses

Lead contamination remains a significant global public health concern, particularly in Kabwe, Zambia, the site of a former lead mining operation. Bioremediation, which utilizes biological materials and processes to remove environmental contaminants, represents a promising approach for addressing lead pollution. However, the development of effective bioremediation systems requires a detailed understanding of the mechanisms underlying metal removal and the feasibility of implementation in low-resource settings. Oceanobacillus profundus KBZ 3-2, a bacterium isolated from Kabwe mine waste, has demonstrated the ability to remove lead from aqueous environments. This study proposes to investigate the mechanism of lead biosorption by this organism, …

Investigating The Impact Of Cyanobacterial Harmful Algal Blooms On Freshwater Bivalves, Destiny Devlin

Theses, Dissertations and Culminating Projects

Harmful algal blooms (HABs) threaten freshwater ecosystems by producing toxins that disrupt aquatic organism functions and pose risks to human health. This study investigated how exposure to toxin-producing cyanobacteria affects the behavior and toxin accumulation of Asian clams (Corbicula fluminea) under controlled laboratory conditions. Asian clams were collected from a freshwater site in New Jersey, maintained in greenhouse bins, and fed either Microcystis novacekii (non-toxin-forming, control N=3) or Microcystis aeruginosa (toxin-forming, experimental N=3) at 100,000 cells/mL for 28 days. Weekly behavioral assays were conducted to track shell opening, burying, clustering, valve closure, foot extension, and time to first opening. Toxin …

Neonicotinoid Bioaccumulation In Bluegill And Bullhead Within Lake Julia And Lake Zumwalde, Jake Stuber

Journal of Earth and Life Science

Brown Bullhead Ameiurus nebulosus, Yellow Bullhead Ameiurus natalis, and Bluegill Lepomis macrochirus are unique in their stark differences. Bullhead are scaleless bottom feeders that can tolerate high pollution and low O₂ conditions. In contrast, Bluegill are scaled, aggressive nesters and are less tolerant of high pollutants or low-oxygen conditions. Among these pollutants include a class of chemicals called neonicotinoids (hereafter referred to as neonics). Neonics are a class of insecticides primarily used within agriculture and pest management. Due to the effectiveness, application has escalated on a global scale. They have been well documented by many toxicology assessments. …

Spiders In The World Of Pesticides: A Review, Jackson L. Mendillo

Williams Honors College, Honors Research Projects

Pesticides and other agrochemicals have varying effects on spiders depending on their mechanism of action and dosage, ranging from behavioral changes and ataxia, to reproductive changes and physiological stress, to lethal non-target effects. Additionally, peptide Hv1a has promising effects as a more narrow-spectrum pesticide.

Environmental Monitoring In Shallow Lakes: Public Health Threats In Urban Waters, Kyleigh E. Johnson

Theses and Dissertations

Lakes are an integral part of urban and suburban communities, providing ecological, recreational, and public health benefits. Many of these lakes are located in densely populated areas and are subject to urban influences on water quality. Algal toxins and Escherichia coli are two common recreational concerns. Algal toxins come from harmful algal blooms that are influenced by nutrient availability and temperature, while bacteria are often introduced through run-off and animal waste. Sampling every 3-4 weeks from May-October 2025 allowed for the assessment of seasonal patterns and site-specific differences across nine lakes in the Richmond area. The highest bacterial concentrations appeared …

Invasion Of Microplastics Into The Reproductive Tissues Of Feral And Domestic Felines, Emma K. Quade

Honors Undergraduate Theses

Although plastics have many useful properties in modern society, once these materials are introduced into the environment, they can cause extensive damage. Following degradation into microplastics (MP), plastic particles less than 5 mm in size, these contaminants can make their way into a variety of different environments and organisms. There are many studies that have investigated the prevalence of MP in marine environments, but fewer studies have looked into terrestrial systems, and even less that have focused on contamination in companion animals. This study sought to investigate the invasion of MP into the reproductive tissues of felines, Felis catus, …

Mineral-Associated Organic Nitrogen Pool Size, Composition, And Accessibility Mediated By Agricultural Management And Soil Geochemical Characteristics, Gabriella M. Griffen, Andrew H. Whitaker, Emma L. Bergh, Marian Carrell, Erik Knatvold, Aniko Konya, A. Stuart Grandy, Andrea Jilling Ph.D., Marco Keiluweit, Rachel Hestrin

Faculty Publications

Mineral-associated organic matter (MAOM) contains a substantial portion of soil nitrogen (N). MAOM-N could serve as an important N source for crops, but its availability and response to agricultural management across different soil types remains largely unknown. We characterized MAOM-N isolated from nine paired soils spanning a range of geochemical characteristics and maintained under two land uses—more intensively managed annual cropping systems or less intensively managed grasslands. On average, we found that MAOM contained approximately two-thirds of total soil N. Across all soil types, more intensive agricultural management resulted in a 50% decline in MAOM-N stocks, as well as a …

Impact Of Cigarette Smoke On Immune And Stromal Cells, Justin Wong

Master's Projects

Cigarette smoke is a plight on human health, being a major contributor to lung diseases. The aryl hydrocarbon receptor (AHR) directs immune regulation and metabolic adaptation in response to environmental toxins. This study investigates transcriptomic changes between wild-type and AHR knockout mouse lung tissue under smoke and air conditions. Single-cell RNA sequencing data were generated by the Butcher Lab and analyzed in Seurat for differential gene expression (DGE) analysis. A two way ANOVA framework was used with DGE analysis to classify genes as smoke induced or suppressed in an AHR dependent or independent manner, and these gene sets were analyzed …

Considerations For The Analysis Of Urinary Environmental Chemical Concentrations During Pregnancy, Danielle R. Stevens, Kaleigh Hinton, Katie M. O'Brien, Jessie P. Buckley, Barrett M. Welch, Jason A. Watts, Antonia M. Calafat, Julianne C. Botelho, Elena Sinkovskaya, Ann Przybylska, George Saade, Alfred Abuhamad, Kelly K. Ferguson

Department of Obstetrics & Gynecology Faculty Publications

Background:

Pregnancy physiology may impact indicators of hydration, affecting exposure assessment in gestational studies with urinary chemical biomarkers.

Methods:

We aimed to characterize hydration and demonstrate the impact of different methods for standardizing urinary chemical biomarker concentrations on exposure descriptives in the Human Placenta and Phthalates Study (n = 303, 2017-2020), a prospective pregnancy cohort with eight study visits between 12 and 38 weeks of gestation. We assessed trajectories and predictors of hydration using urine flow rate (UFR) and specific gravity (SG). Likewise, we examined trajectories and predictors of mono-n-butyl phthalate (MBP), for which concentrations were unstandardized or standardized via …