Toxicology Commons^™

Metal Nanomaterials: Immune Effects And Implications Of Physicochemical Properties On Sensitization, Elicitation, And Augmentation Of Allergic Disease, Katherine Adair Roach

Graduate Theses, Dissertations, and Problem Reports (ETD)

Many allergenic metals are being manufactured in nanoparticulate forms. Although the decreased size profile of metal nanomaterials has been consistently associated with more pronounced lung toxicity compared to larger materials, it is unclear if metal-induced immunotoxic effects exhibit a similar size-dependency.

The central hypothesis of these studies was that metal nanoparticles cause more pronounced immunomodulatory effects on allergic processes than larger forms of respective metals. Moreover, it was anticipated that, similar to their inflammatory potential in airways, the magnitude of these responses would correlate best with the dose metric of surface area.

The first set of studies utilized fine and …

Multigenerational Genomic And Epigenetic Effects Of Manufactured Silver Nanomaterials In Caenorhabditis Elegans, Anye Wamucho

Theses and Dissertations--Toxicology and Cancer Biology

There has been an increase in the incorporation of silver nanomaterials into consumer products due to their antimicrobial properties. Therefore there is potential for silver nanoparticles (Ag-NPs) to leach out into the environment during different life-cycle stages of these nanomaterial-containing products. Concern about the toxicity of Ag-NPs has led to investigations into their toxic effects on a variety of organisms mainly using acute and sub-chronic, single-generation exposures. The focus of this project was to understand the effects of long-term continuous multigenerational exposure to AgNO₃ and Ag-NPs in both pristine and environmentally transformed forms, on the model organism, Caenorhabditis elegans …

Negative Effects Of Common Herbicides On Non-Target Invertebrates, Debbi Albanese

College of Graduate Studies: Theses & Dissertations

Three herbicide formulations, Roundup® Ready to Use Weed and Grass Killer, Bayer Advanced Southern Weed Killer for Lawns and Pure 20% Vinegar Solution were directly applied to eggs of four species of butterflies, Danaus plexippus, Papilio cresphontes, Papilio polyxenes and Papilio troilus. Roundup and Bayer Advanced containing 2,4-D, mecoprop-p and dicamba significantly reduced hatch success in all four species. Lethal and sublethal effects of these herbicides on the earthworm, Eisenia andrei, was also examined. Direct contact by E. andrei with a heavy dose of the herbicides applied to tops of soil 24 hours prior was lethal to earthworms. …

A Compromised Liver Alters Pcb Toxicity And Nutrient Metabolism, Jazmyne D. L. Barney

Theses and Dissertations--Toxicology and Cancer Biology

Environmental contamination is a public health concern. In particular persistent organic pollutants like Polychlorinated Biphenyls (PCBs) have been associated with multiple chronic inflammatory diseases, including non-alcoholic fatty liver disease (NAFLD). NAFLD prevalence has steadily increased and is expected to continue to rise with an estimated 25% of the world’s population and 80-100 million people affected in the United States alone. Importantly, the liver is the primary site for endobiotic and xenobiotic metabolism, hence its proper function is critical for the body’s response to innate and extrinsic molecules. One way to combat the deleterious effects of PCB toxicity and fatty liver …

Ground Ingredients: Analysis Of Lead Exposure In The California Condor’S (Gymnogyps Californianus) Ground Foraging Habitat, Evan Michael Mcwreath

Graduate Theses, Dissertations, and Problem Reports (ETD)

The California Condor (Gymnogyps californianus) is a critically endangered species that reached its nadir in 1987 with a population of 27 birds in the wild. Intensive management efforts have been implemented to aid the condors’ recovery, however, anthropogenic factors, like use of lead ammunition, continue to cause fatalities in this vulnerable population. Lead toxicosis, which is responsible for approximately 40% of all condor deaths since 1992, is one of the most significant threats to condors. In birds lead poisoning leads to neurological dysfunction, reproductive impairment, immune suppression, gastrointestinal disturbance, anemia, and ultimately increased vulnerability to predation, starvation, and infection. For …

Acute And Repeated Effects Of Synthetic Cannabinoid Agonism And Cannabinoid Receptor 1 Positive Allosteric Modulation, Kristen R. Trexler

Graduate Theses, Dissertations, and Problem Reports (ETD)

Recent years have seen a rise in the diversity and use of synthetic cannabinoids. Currently, there is little known about the effects of specific synthetic cannabinoid compounds. As such, little research has been done evaluating the acute and chronic effects of synthetic cannabinoid administration or the development of tolerance and withdrawal. The present study aimed, in part, to evaluate the acute and repeated effect of a third-generation synthetic cannabinoid, AB-FUBINACA. Mice were treated with AB-FUBINACA (0.1-3 mg/kg, i.p.) or vehicle and were tested repeatedly in the tetrad battery of assays, which included tests of catalepsy, antinociception, hypothermia, and locomotor activity. …

Effects Of E-Cigarette Flavoring Chemicals On Human Macrophages And Bronchial Epithelial Cells, Anna Manzi Morris

Graduate Theses, Dissertations, and Problem Reports (ETD)

E-cigarettes and vapes are relatively new devices which are popular among young adults and teens. These devices vaporize an “e-liquid” for the user to inhale, which typically contains a mixture of propylene glycol (PG), vegetable glycerin (VG), varying concentrations of nicotine, and flavoring chemicals. Due to these flavoring chemicals being intended for ingestion as a food additive, their respiratory health effects are not well understood. Thousands of e-cigarette flavors are available on the market, many of which have the potential for toxicity. The majority of e-liquid flavoring chemicals (ELFCs) have not been tested for inhalation safety. In this study, we …

The Acute Effect Of Propanil On Reproductive Hormones, Ovarian Gene Expression And Splenic Cells In C57bl/6 Female Mice, Malia Danielle Berg

Graduate Theses, Dissertations, and Problem Reports (ETD)

Earlier evidence indicates exposure to propanil, a post-emergent herbicide used on rice and wheat fields, increases the number of antibody-secreting cells (ASC) in the spleen of mice after immunization with heat-killed Streptococcus pneumoniae (HKSP, 2x10⁸ CFU). Interestingly, an intact hypothalamic-pituitary-gonadal (HPG) axis is required for this immune response assessed on day 7-10 after immunization in female mice. Hence, an overarching premise is that propanil arbitrates the connection between the reproductive and immune system by altering the concentration of hormones involved in the HPG axis, which may then affect the populations of splenic cells. Hypotheses were tested with C57Bl/6 female …

Electrochemical Detection Of Fentanyl Using Screen-Printed Carbon Electrodes With Confirmatory Analysis Of Fentanyl And Its Analogs In Oral Fluid Using Liquid Chromatography-Tandem Mass Spectrometry, Colby E. Ott

Graduate Theses, Dissertations, and Problem Reports (ETD)

Utilizing screen-printed carbon electrodes (SPCEs), a fast, simple, and sensitive approach toward the detection, identification, and quasi-quantitation of fentanyl was achieved both in an electrochemical cell and as a drop on the electrode surface. Electro-oxidation of fentanyl at the electrode was demonstrated using adsorptive stripping square-wave voltammetry between -0.5 V and +1.6 V with 100 mM Tris-HCl buffer at pH 8.5 as supporting electrolyte. Parameter optimization was conducted during method development to include supporting electrolyte and pH, electrochemical technique, pre-treatment and equilibration time, and various surface modifications. The simplest method utilizing an unmodified SPCE was determined to be appropriate for …

Halogenated Flame Retardants And Organophosphate Esters In The Air Of Electronic Waste Recycling Facilities: Evidence Of High Concentrations And Multiple Exposures, Sabrina Gravel, Jérôme Lavoué, Bouchra Bakhiyi, Miriam L. Diamond, Liisa M. Jantunen, Jacques Lavoie, Brigitte Roberge, Marc-André Verner, Joseph Zayed, France Labrèche

Études primaires

Background

In response to a worldwide increase in production of electronic waste, the e-recycling industry is rapidly rowing. E-recycling workers are exposed to many potentially toxic contaminants, among which flame retardants (FRs), mainly suspected of being endocrine disruptors, are thought to be the most prevalent.

Objective

To conduct an exposure assessment of four chemical groups of FRs in Canadian e-recycling facilities, and to identify the main cofactors of exposure.

Methods

Personal air samples were collected over a workday for 85 workers in six e-recycling facilities, grouped into three facility sizes, and for 15 workers in control commercial waste facilities. Total …

Critical Physicochemical Properties For Nanoparticle Toxicity: Impact Of Surface Coating And Size On Particle-Induced Cell Transformation And Inflammatory Response, Tiffany Kornberg

Graduate Theses, Dissertations, and Problem Reports (ETD)

Nanoparticles, which measure 100 nm in at least one dimension, have surged in development, production, and use for a wide range of applications. However, the rapid pace of development for these emerging materials with unclear/unknown toxicity profiles makes it difficult to adequately assess health risk associated with exposure. One critical obstacle which limits scientific research to fill these critical knowledge gaps is the lack of accurate and predictive models for nanotoxicology studies, particularly those which involve occupationally relevant exposure scenarios (pulmonary exposure to low dose of particles in the circulating air). Typically, animal models are used to assess potential systemic …

Potential Impact Of Northern Resource Development On Aquatic Biota: Toxicity Of Chromium And Rare Earth Element Processing Reagent, So Yeon Choi

Theses and Dissertations (Comprehensive)

Chromite and rare earth element development was identified in the 2015 Canadian Federal budget as a significant opportunity, however, key data gaps exist regarding the environmental concerns related to these resource developments. Chromium is essential in the production of stainless steel, and no suitable substitute is known. Rare earth elements (REEs) are a series of metals that are composed of 15 lanthanides, as well as scandium and yttrium. Uses for REEs range from electronic devices (i.e. cell phones, computers, televisions) to magnets and controlling nuclear reactors. While commercial production of REEs signify a great economic opportunity for Canada, key data …

Toxicity Of Formulated Insecticide Mixtures To Apis And Non-Apis Bees, Joseph Edward Belsky

Graduate Theses and Dissertations

This work investigates ecotoxicology of new insecticide mixtures to Apis and non-Apis bees. Previous studies have demonstrated the acute and sub-lethal toxicity of individual active ingredient insecticides to honey bees and to a lesser extent non-Apis bees. However, the contact toxicity of formulated premix insecticides containing multiple active ingredients to bees has not been thoroughly assessed. To address this void, laboratory studies simulating exposure to four premix insecticides under different field-realistic scenarios were conducted for two bee species.

Honey bee, Apis mellifera (Linnaeus) contact exposure was examined by simulating three scenarios: (1) when bees continuously forage in a field and …

The Role Of Cyp2a5 In Cadmium-Induced Liver Injury, Julia Salamat

Electronic Theses and Dissertations

Cadmium is present in food and groundwater. Tobacco smoking and occupational exposure are also major sources for cadmium. Cadmium is primarily accumulated in liver, a major organ metabolizing exogenous chemicals. Chemical metabolism may cause detoxification, but it can also cause bio-activation resulting in liver damage. Cytochrome P450s (CYP) are major liver metabolism enzymes, and cadmium chloride (CdCl2) can induce CYP2A5 in mice. We examined the effect of CYP2A5 on CdCl2-induced liver injury using CYP2A5-knockout (cyp2a5-/-) mice. The cyp2a5-/- mice and their control WT mice were injected CdCl2 intraperitoneally at 5 mg/kg body weight, respectively, to induce liver injury. …

The Role Of Cathelicidin In The Regulation Of Gut Microbiota And Inflammasome Activation In Alcoholic Liver Disease., Fengyuan Li

Electronic Theses and Dissertations

Alcoholic liver disease (ALD) is characterized by gut dysbiosis and hepatic and intestinal inflammation. Gut microbiota is critically maintained by antimicrobial peptides (AMPs) expressed in the epithelial and immune cells. AMPs are also identified as immune-regulators in various diseases. Previous studies demonstrated that deficiency of AMPs REG3 lectins exacerbated alcoholic steatohepatitis. LL-37 is the sole member of human cathelicidin AMP family, named CRAMP in mouse. Despite of the extensive studies in infectious diseases and in gut-microbiota-related inflammatory bowel disease, the role of LL-37/CRAMP in ALD is yet unknown. Our previous studies showed a decreased intestinal CRAMP in a mouse model …

Analysis Of Synthetic Opioids In Postmortem Blood, Vitreous Humor, And Brain Tissue, Rachel K. Chesser

Student Theses

In the United States, the use of new synthetic opioids (e.g. fentanyl and derivatives) has become an increasing health issue with thousands of overdose deaths being observed since 2013. With the high mortality rate associated with these substances, postmortem analyses and interpretation of synthetic opioids has become extremely important. However, due to the novelty of these compounds, the available data is limited and provides challenges to toxicologists. The focus of this project was to examine the postmortem distribution of new synthetic opioids in blood, vitreous humor, and brain tissue. New methods were developed and validated to quantify 13 synthetic opioids …

Postmortem Toxicology Of New Synthetic Opiods, Marta Concheiro, Rachel Chesser, Justine Pardi, Gail Cooper

Publications and Research

One hundred fifteen Americans die every day from opioid overdose. These overdose fatalities have been augmented by the increased availability of potent synthetic opioids, such as fentanyl and its derivatives. The death rate of synthetic opioids, other than methadone, increased by 72.2% from 2014 to 2015, and doubled from 2015 to 2016, situating the USA in the midst of an opioid overdose epidemic. The analytical identification of these opioids in postmortem samples and the correct toxicological data interpretation is critical to identify and implement preventive strategies. This article reviews the current knowledge of postmortem toxicology of synthetic opioids and the …

Neurobehavioral Evaluation Of Mice Dosed With Water Hemlock Green Seeds And Tubers, Camila F. P. Orlando-Goulart, Kevin D. Welch, James A. Pfister, Daniel S. Goulart, Adilson D. Damasceno, Stephen T. Lee

Poisonous Plant Research (PPR)

Water hemlock are plants of the genus Cicuta and are toxic to animals and humans. The primary toxin is cicutoxin, which is abundant in the tubers, but less abundant in other parts of the plant. Other cicutoxin-like compounds, such as cicutols, which may also contribute to the toxicity of water hemlock, are more abundant in non-tuber plant parts. The objective of this study was to determine the toxicity of different parts of water hemlock and characterize their effects on motor function/coordination in mice. An aqueous extract of green seeds, dry seeds, tubers, flowers and stems of water hemlock was dosed …

The Value Of Chemical Defense: The Effects Of Toxin Milking On The Physical, Physiological, And Behavioral Performance Of Cane Toads (Rhinella Marina), Ryann Blennerhassett

Independent Study Project (ISP) Collection

Amphibians have cutaneous glands on their skin which produce a number of toxic compounds that serve as protection against predators and microorganisms. Cane toads (Rhinella marina) have large parotoid glands located on their shoulders to store toxins, many of which are derived from lipids and are thus energetically expensive to produce. I used a combination of field and laboratory studies to investigate behavioral and physiological consequences of toxin loss and replenishment in cane toads. In a cross-sectional study, free-ranging toads were euthanized and dissected to identify correlations between toxin content and morphology /physiology. Experimental manipulations (manually expressing toxin from glands) …

A Review Of Inhalation Exposure To Mold And Adverse Health Outcomes, Amanda S. Persad, Todd Stedeford, Marek Banasik, Tomasz T. Suchecki, Carlos A. Muro-Cacho

Florida State University Journal of Land Use and Environmental Law

No abstract provided.