Environmental Health Commons^™

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 . …

Evaluation Of The Dnazyme Gr5 For The Determination Of Lead Speciation In Natural Waters, Gaganprit Gill

Theses and Dissertations (Comprehensive)

This thesis explores the development and application of a DNAzyme-based biosensor designed to detect labile metal species in environmental samples. Real time and on-site monitoring of labile metal fractions would make a valuable contribution to environmental management, as these fractions are the most bioavailable and pose significant toxicity risks to aquatic organisms. Conventional methods for detecting labile metals, while effective, are often burdened by high costs, complexity, and lengthy processing times, making them less ideal for rapid and widespread environmental assessments.

The first manuscript of this thesis (chapter 2) establishes the fundamental capabilities of the Pb²⁺-specific DNAzyme GR5 …

Investigation Of The Environmental Factors Regulating The Biomass And Toxin Production Of The Benthic Cyanobacterium Microseira Wollei In Lake Wateree, South Carolina, Kara Clyburn

Theses and Dissertations

Impacts from anthropogenic activities and climate change are significantly altering nitrogen (N) cycling processes and biological productivity along the freshwater to marine continuum, and the acceleration rate of excessive N and phosphorus (P) concentrations entering aquatic environments is unprecedented. As a result, nutrient pollution is contributing to the increasing magnitude and duration of cyanobacterial harmful algal blooms (cHABs), oxygen (O2) depletion, loss of biodiversity, and impacts to human and ecosystem health. Lake Wateree, South Carolina (SC) is a freshwater drinking and contact recreational water resource with elevated symptoms of eutrophication, including the increasing prevalence of the N2 fixing benthic cyanobacterium …

Anticancer Potential Of The Leaf Extracts From The Selected Croton Species, Peter V. Fayyu, Joan J.E. Munissi, Stephen S. Nyandoro, Flora Stephano

Tanzania Journal of Science

The reported investigations were aimed at establishing anticancer potential of the leaf extracts from Croton dictyophlebodes (CDE), C. kilwae (CKE) and C. longipedicellatus ssp austrotanzanicus (CLE). In vitro cytotoxicity assays of the extracts were performed against human laryngeal cancer cell line (HEp-2) and human breast cancer cell line (MCF-7), while in vivo toxicological studies were done using Swiss albino mice (Mus musculus) following the Organization for Economic Cooperation and Development guideline number 423 of 2001. Results for in vitro assays revealed that CDE and CLE induced cytotoxicity to MCF-7 and HEp-2 cell lines at EC50 values of 86 and 63 …

Antidiabetic Potential Of Vitex Mombassae Fruits Extract In Streptozotocin-Nicotinamide Induced Diabetic Wistar Rat Model, Mussa B. Mbegeze, Joan J.E. Munissi, Flora Stephano, Ramadhani S.O. Nondo, Stephen S. Nyandoro

Tanzania Journal of Science

Besides changes in life styles and improper dietary patterns, the rapidly increasing burden of diabetes mellitus type 2 is correlated with antidiabetic agents currently in clinical use, which are costly, less effective, and present undesirable side effects. Natural products from plants are promising alternative sources for developing more effective and cost friendly antidiabetic agents. This study therefore investigated the antidiabetic potential of Vitex mombassae fruits extract (VMFE) in streptozotocin-nicotinamide induced diabetic Wistar rat model. Oral acute toxicity test was conducted in male Wistar rat using up and down method by following OECD Guideline 423 (2002). No clinical signs of toxicity …

Subchronic Oral Cylindrospermopsin Exposure Alters The Host Gut Microbiome And Is Associated With Progressive Hepatic Inflammation, Stellate Cell Activation, And Mild Fibrosis In A Preclinical Study, Punnag Saha, Macayla Upright, Dipro Bose, Subhajit Roy, Ayushi Trivedi, Madhura More, Geoff Scott Ph.D., Bryan W. Brooks, Saurabh Chatterjee

Faculty Publications

Epidemiological studies have reported a strong association between liver injury and incidences of hepatocellular carcinoma in sections of humans globally. Several preclinical studies have shown a strong link between cyanotoxin exposure and the development of nonalcoholic steatohepatitis, a precursor of hepatocellular carcinoma. Among the emerging threats from cyanotoxins, new evidence shows cylindrospermopsin release in freshwater lakes. A known hepatotoxin in higher concentrations, we examined the possible role of cylindrospermopsin in causing host gut dysbiosis and its association with liver pathology in a mouse model of toxico-pharmacokinetics and hepatic pathology. The results showed that oral exposure to cylindrospermopsin caused decreased diversity …

Behavioral Alterations Following Exposure To A Mixture Of Lead And Atrazine During Early Development In The Zebrafish Model System, Anusha Kv Lakshmi Dharmavathi

The Journal of Purdue Undergraduate Research

Lead (Pb) and atrazine (ATZ) are hazardous environmental toxicants that can exist as a mixture in potable water. Numerous single chemical studies on Pb and ATZ support adverse health outcomes, including neurotoxicity, but mixture studies are limited. Th e aim of this study is to test the hypothesis that Pb and ATZ mixtures result in a greater than additive toxicity, causing increased adverse health outcomes than single chemical exposures. Th e zebrafish model system was exposed to 3 or 30 ppb (µg/L) ATZ, 10 ppb (equivalent to 0.1 µg/dL) or 100 ppb Pb, along with mixtures of each beginning at …

Toxicity Assessment Of The Crude Ethanolic Pod Extract Of Swartzia Madagascariensis Desv. In Rats, Adelina A. Mwakalila, Saada M. Mbepera, Shaabani A. Mshamu, Amina Msonga, Washa B. Washa

Tanzania Journal of Science

This study assessed toxicity of the crude ethanolic pod extracts of Swartzia madagascariensis Desv in Wistar rats. Forty (40) Wistar rats aged 8–10 weeks were orally administered with crude extracts from pods of S. madagascariensis. Chemical analysis of serum and histopathology of liver and kidney from test animals were performed to determine the levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), and creatinine in serum. In addition, serum albumin levels were also determined. The levels of ALT, AST and creatinine were found to be high in groups treated with crude extracts compared to the control group, suggesting some damage in …

Toxicity Of The Technology Critical Elements Germanium And Yttrium To Daphnia Magna And Hyalella Azteca And The Influence Of Toxicity Modifying Factors, Rashid Shah

Theses and Dissertations (Comprehensive)

Technology critical elements (TCEs) are increasingly used in high and green technologies but there is little aquatic toxicity data for TCEs, particularly in fresh water. The objective of this study was to investigate the toxicity of two TCEs, Ge and Y, to Daphnia magna and Hyalella azteca and to understand the role of natural organic matter and cations on toxicity modification. Testing followed standard methods. The 48 h EC50 for D. magna was 11.6 (95% CI of 9.64-13.8) mg Ge/L based on measured dissolved concentrations at test end. The addition of NOM at 10 mg DOC/L resulted in a significant …

The Interactive Effects Of Nontoxic Levels Of Microplastics - Textile Microfibers And Tire Wear Particles, On The Acute Toxicity Of Bifenthrin In The Estuarine Grass Shrimp, Palaemonetes Pugio, Xiaoxuan Fan

Theses and Dissertations

Contemporary pollution issues are primarily focused on Contaminants of Emerging Concern (CECs) which may include Brominated and Fluorinated flame retardants, Pharmaceuticals and Personal Care Products (PPCPs), Contemporary Use Pesticides (CUPs), nanomaterials and microplastics (Muraya et al., 2014). Tire wear particles and textile microfibers are examples of CECs which may gradually increase in the environment and may cause adverse effect on the health of some aquatic species (Marwood et al., 2011; Taylor et al., 2016). Microplastic particles are so small that they can be ingested by many marine species such as filter feeders and small particle feeders including mollusk and crustaceans, …

Characterization, Bio-Uptake And Toxicity Of Polymer-Coated Silver Nanoparticles And Their Interaction With Human Peripheral Blood Mononuclear Cells, Sahar Pourhoseini, Reilly T. Enos, Angela E. Murphy, Bo Cai Ph.D., Jamie Lead

Faculty Publications

Silver nanoparticles (AgNPs) are widely used in medical applications due to their antibacterial and antiviral properties. Despite the extensive study of AgNPs, their toxicity and their effect on human health is poorly understood, as a result of issues such as poor control of NP properties and lack of proper characterization. The aim of this study was to investigate the combined characterization, bio-uptake, and toxicity of well-characterized polyvinylpyrrolidone (PVP)-coated AgNPs in exposure media during exposure time using primary human cells (peripheral blood mononuclear cells (PBMCs)). AgNPs were synthesized in-house and characterized using a multimethod approach. Results indicated the transformation of NPs …

Understanding The Toxicity Of Single Hydrocarbons, Oil, And Dispersed Oil: A Species Sensitivity Assessment For Five Atlantic Coral Species, Nicholas R. Turner

HCNSO Student Theses and Dissertations

Coral reefs are keystone coastal ecosystems that are at risk of exposure to petroleum hydrocarbons from a range of sources, including oil spill incidents and chronic runoff, and are usually one of the highest valued natural resources for protection in Net Environmental Benefit Analysis (NEBA)/Spill Impact Mitigation Assessment (SIMA) of response methods and environmental damage. Previous research evaluating hydrocarbon impacts to corals has resulted in no clear characterization of sensitivity, as work has generally focused on higher-level effects, compounded by significant variability in experimental methodology. This represents an important knowledge gap in oil spill preparedness and response as it relates …

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 Effects Of Climate Change On The Ecotoxicology Of Contaminants Of Emerging Concern: Flame Retardants, Contemporary Use Pesticides And Pharmaceuticals Personal Care Products On The Estuarine Grass Shrimp, Palaemontes Pugio, Rajaa Nouri Al-Yassein

Theses and Dissertations

Global Climate Change may adversely affect the environment, increasing water temperature and altered salinity which may affect the toxicity of both legacy pollutants and Contaminants of Emerging Concern (CECs). Acute, 96 hour toxicity tests with adult grass shrimp (Palaemonetes pugio) assessed the effects of CECs (Polybrominated Diphenyl Esther (PBDE) – 47, ibuprofen, bifenthrin, triclosan, and bifenthrin/triclosan mixtures) under Standard Conditions (20°C, 20psu) and different Climate Change Conditions (30°C, and/or35psu) In addition, the grass shrimp microbiome (e.g. Vibrio bacteria) were assessed following acute triclosan exposures at the Maximum Exposure Concentration (MECs) and Minimum Inhibitory Concentration (MICs) under standard conditions. …

Do Toxicity Modifying Factors Influence Acute Or Chronic Toxicity Of Thulium To Hyalella Azteca?, Alexandria H. Loveridge

Theses and Dissertations (Comprehensive)

The industrial demand for rare earth elements (REEs) is growing and as a result, environmental exposure is a concern. Very little is understood about the toxicity of REEs in aquatic environments. The objective of this research is to evaluate the acute and chronic toxicity of Tm and to also understand the toxicity modifying influence of dissolved organic matter (DOM) and cationic competition (Ca2+, Mg2+ and Na+). Furthermore, the aim of this study was to determine linkages between Tm bioaccumulation, growth and survival during chronic exposures. Standard methods (Environment Canada) were followed for both 96h acute and 14d chronic tests, in …

The Chronic Toxicity Of Titanium Dioxide Nanoparticles To The Freshwater Amphipod Hyalella Azteca, Gurkirpal S. Malhi

Theses and Dissertations (Comprehensive)

There has been an increased use of metal-oxide nanoparticles in both commercial and consumer products. The use of these products and waste generated during manufacture may ultimately be released into the aquatic environment and the potential for these contaminants to cause impacts must be assessed. This study examines the effect of titanium dioxide (TiO₂) nanoparticles (NPs) on Hyalella azteca. Chronic toxicity exposures were conducted in 400mL of spiked test solution and contained 20 neonates. Samples collected for characterization of Ti in TiO₂ NP exposure solutions were digested using ammonium persulfate as an oxidizing agent and dissolved …

Evaluating Acute Toxicity Of Cadmium To Chironomid Using Hemoglobin As A Molecular Biomarker, Jun Taek Oh

Seton Hall University Dissertations and Theses (ETDs)

Effects of cadmium (Cd), a heavy metal contaminant, on hemoglobin were investigated in aquatic midge fly larvae of the Family, Chironomidae. In this study, chironomid populations from one polluted site, Kearny Marsh, New Jersey, two reference sites, North East Creek, and Bass Harbor, ME, and a laboratory population were taxonomically identified and tested for their sensitivity to Cd. Heavy metals in tissue, water and sediment were analyzed using Atomic Absorption Spectroscopy. Water quality at each site was assessed by measuring pH, dissolved oxygen (DO), oxidation-reduction potential ( eH), salinity and temperature. Hemoglobin proteins in individual larvae were easily detected using …