Toxicology Commons^™

Arsenic Speciation Analysis Of Biological Fluids : A Study Of Liquid Chromatography Coupled To Analytical Atomic Spectrometric Instrumentation, Kanna Ito

Legacy Theses & Dissertations (2009 - 2024)

Arsenic exists as many different chemical forms including inorganic, methylated and dietary species. The toxicity of these species varies: some are highly toxic and can cause adverse health effects in many parts of the body; others are considered relatively non-toxic. Monitoring arsenic exposure is usually accomplished by its direct measurement in biological fluids. Urine is the specimen of choice for assessing arsenic exposure, because of its short biological half-life in blood. There have been very few studies of arsenic species in blood, yet such research can provide valuable information on arsenic distribution and its metabolism in the body.

Evaluating And Regulating Lead In Artificial Turf, Gregory Van Ulirsch, Kevin Gleason, Shawn Gerstenberger, Deaphne B. Moffett, Glenn Pulliam, Tariq Ahmed, Jerald Fagliano

Environmental & Global Health Faculty Research

Background: In 2007, a synthetic turf recreational field in Newark, New Jersey, was closed because lead was found in synthetic turf fibers and in surface dust at concentrations exceeding hazard criteria. Consequently, public health professionals across the country began testing synthetic turf to determine whether it represented a lead hazard. Currently, no standardized methods exist to test for lead in synthetic turf or to assess lead hazards.

Objectives: Our objectives were to increase awareness of potential lead exposure from synthetic turf by presenting data showing elevated lead in fibers and turf-derived dust; identify risk assessment uncertainties; recommend that federal and/or …

Antibactertial Property And Toxcity Study Of Medicinal Plant Tinospora Crispa L., Altammar Khadijah Ahmed Y.

Student Works (2010-2019)

Tinospora crispa is a medically important herb used for centuries in traditional medicine for the treatment of various ailments. The aim of this study was to investigate the safety of the aqueous and alcoholic extract of Tinospora crispa by determining its toxicological effects after acute administration in rats, and to investigate the antibacterial activity of both extracts. Disc diffusion and broth dilution methods were carried out in determining the antibacterial effects of the plant extract on the pure cultures of clinical isolates of 8 MRSA and S. aureus ATCC strain. The disc-diffusion method of the ethanolic extracts showed inhibition zone …

Characterization Of Arsd: An Arsenic Chaperone For The Arsab As(Iii)-Translocating Atpase, Jianbo Yang

Wayne State University Dissertations

Arsenic is a metalloid toxicant that is widely distributed throughout the earth's crust and causes a variety of health and environment problems. As an adaptation to arsenic-contaminated environments, organisms have developed resistance systems. In bacteria and archaea various ars operons encode ArsAB ATPases that pump the trivalent metalloids As(III) or Sb(III) out of cells. In these operons, an arsD gene is almost always adjacent to the arsA gene, suggesting a related function. ArsA is the catalytic subunit of the pump that hydrolyzes ATP in the presence of arsenite or antimonite. ArsB is a membrane protein which containing arsenite-conducting pathway. ArsA …

Perubahan Tahap Kerintangan Dalam Nyamuk Culex Quinquefasciatus, Aedes Aegypti Dan Aedes Albopictus Terhadap Insektisid Malathion, Permethrin Dan Temephos., Hidayati Hamdan

Student Works (2010-2019)

In this study, selective pressure bioassay test against malathion, permethrin and temephos had been carried out at the larval stage of Cx. quinquefasciatus, Ae. aegypti and Ae. albopictus. Meanwhile, only selection pressure against malathion and permethrin was taken for the adults. The rate of resistance had reduce 52.68 and 13,130 fold in the malathion and permethrin strains of Cx. quinquefasciatus larvae while for the adults, a reduction of 6.14 and 10.37 fold had been observed. A reduction of 4.97, 64.16 dan 51.0 fold had been observed for the Ae. aegypti larvae while 2.74 and 4.48 fold in their adults. Treatment …

Immunomodulatory Effects Of Diesel Exhaust Particles, Ashley Kay Masterson

Boise State University Theses and Dissertations

Diesel exhaust particles (DEP) represent a key component of particulate matter pollution and a serious cardiopulmonary health risk, as these particles have been associated with increased morbidity and mortality following exposure. In this study, we investigated the immunomodulatory properties of DEP on helper T cells by measuring changes in activation, cytokine production, and viability. The expression of CD40L, a key regulatory protein, was increased by DEP in the absence of physiologic stimuli without parallel increases in the expression of CD25 and CD69 activation markers. Additional studies utilizing a variety of T cell stimuli, including T cell receptor signaling and CD28 …

Monitoring Of Heavy Metal Loading Into The Wetlands South Of Lake Victoria Basin, Nothern Tanzania, M K D Mutakyahwa, J R Ikingura, G Y S Mtui

Tanzania Journal of Science

The paper discusses sources, concentrations and physicochemical parameters of heavy metals of environmental concern in the wetlands of Lake Victoria basin in Tanzania. The metals investigated include copper (Cu), lead (Pb), zinc (Zn), cadmium (Cd), chromium (Cr), nickel (Ni), arsenic (As), manganese (Mn), cobalt (Co) and mercury (Hg). These metals are released into the wetlands via weathering and erosion of rock formations, mining operations and industrial activities, discharge of municipal and domestic waste, and use of agrochemicals. The levels of these heavy metals in soil, sediment, water, and biota differ. Wetlands impacted by gold mining activities in the South Lake …

Effects Of The Polycyclic Musk Hhcb On Individual- And Population-Level Endpoints In Potamopyrgus Antipodarum, Signe Pedersen, Henriette Selck, Daniel Salvito, Valery E. Forbes

Valery Forbes Publications

Although the polycyclic musk 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethylcyclopenta[γ]-2-benzopyran (HHCB) is frequently detected in aquatic sediments, very little is known about its effects on sediment-feeding organisms. Effects of sediment-associated HHCB on growth, feeding rate, survival and reproduction in the gastropod Potamopyrgus antipodarum were measured in the laboratory. Snails were exposed to six nominal HHCB concentrations: 0, 0.1, 1, 10, 30 and 100 μg g−1 dry weight (dw) sediment. Adult survival and growth were not affected by HHCB. However, juvenile growth and survival, reproduction, time to first reproduction and adult feeding rate were more sensitive endpoints and declined with increasing HHCB concentration. Individual-level endpoints for …

In Vitro Toxicity Of Silver Nanoparticles In Human Lung Epithelial Cells, Christina R. Kearns

Theses and Dissertations

Nanotechnology is quickly becoming incorporated into everyday products and uses. Silver nanoparticles, specifically, are being used in commercial products, to include aerosols. The purpose of this research was to determine whether silver nanoparticles are toxic to human lung epithelial cells. Different types (coated vs. uncoated), concentrations (10, 50, 100, and 200 µg/mL) and sizes (coated 5 and 80nm, uncoated 10 and 80nm) of silver nanoparticles were used during this study. Toxicity measurements were completed through in vitro techniques. Another study was also completed on toxicity mechanisms by measuring the reactive oxygen species (ROS) generated. Results showed that silver nanoparticles induce …

The Amphipod Orchomenella Pinguis — A Potential Bioindicator For Contamination In The Arctic, Lis Bach, Valery E. Forbes, Ingela Dahllöf

Valery Forbes Publications

Indigenous organisms can be used as bioindicators for effects of contaminants, but no such bioindicator has been established for Arctic areas. Orchomenella pinguis is a benthic amphipod, ubiquitous in the Arctic and can be found in high numbers. We collected O. pinguis at sites with different contamination levels. Population characteristics (body length distribution, average dry weight and amphipod organic content) were related to sediment contaminant concentrations, in order to identify suitable endpoints for using this species as a bioindicator. We show that O. pinguis was prevalent in both clean and contaminated areas, easy to sample and that its population characteristics …

Genetic And Non-Genetic Factors That Cause Inter-Individual Variations In Cyp2a13 Gene Expression, Hong Wu

Legacy Theses & Dissertations (2009 - 2024)

The overall goal of this dissertation is to investigate the mechanisms underlying the large interindividual variations in susceptibility to lung carcinogenesis. We focused on CYP2A13, a respiratory tract-specifically expressed enzyme, which is the most efficient P450 towards bioactivation of a tobacco-related carcinogen 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK). The expression level of CYP2A13 varies substantially among human lung samples. Our central hypothesis is that CYP2A13 expression level is affected by both genetic regulators and non-genetic factors. The specific aims are 1) to identify the mechanisms underlying the decreased allelic expression of a CYP2A13 allele (7520C>G); 2) to identify frequent single-nucleotide polymorphisms (SNPs), associated …

Application Of Multiple Mass Spectrometric Techniques In The Isolation, Determination And Characterisation Of The Marine Toxins; Azaspiracid, Keith O'Callaghan

Theses

The Azaspiracids are a class of polyether marine biotoxins that present a significant health risk to consumers of shellfish. Since their discovery in the late 1990s several human intoxications have been reported, and traced to Irish shellfish farms resulting in closures or harvest rejections. As such incidents involving azaspiracid shellfish poisoning have a major socio-economic impact on communities that rely on shellfish farming revenues.

Recent evidence suggests that azaspiracid poisoning events may become more commonplace. With this increased risk the understanding of azaspiracids mode of action and biological targets becomes crucial. To support these endeavours effective analytical methods need to …

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 …

Effect Of Increased Carbon Dioxide Levels On Urushiol Production In Toxicodendron Radicans And Toxicodendron Toxicarium, Meredith Gilbert

Theses and Dissertations

It is hypothesized that global warming is at least partially due to increased greenhouse gases, one of which is carbon dioxide. An increase in atmospheric carbon dioxide has been shown to stimulate higher rates of plant productivity, including the production of plant toxins like urushiol. Urushiol, a secondary plant compound produced in members of the Anacardiaceae family, causes dermatitis in sensitive individuals. An increase in urushiol production could increase the reactivity of certain individuals to plants like poison oak and poison ivy. To determine how elevated levels of atmospheric carbon dioxide would effect urushiol production, 16 samples of poison ivy …

Urinary Excretion Of (1-3)-Beta-D-Glucans., Debra K. Head

Electronic Theses and Dissertations

(1→3)-β-D-Glucans are carbohydrate polymers that are present in the cell wall of various fungi and bacteria; they are pathogen associated molecular patterns that circulate during infection and modulate immunity. Our laboratory has previously established the pharmacokinetics of intravenously and orally administered glucans; the present studies investigated the renal excretion of (1→3)-β-D-glucans following intravenous and oral administration. Three fluorescently-labeled glucans were administered to adult male rats in the presence or absence of toxic challenge. Urine specimens were collected and analyzed by fluorescence spectroscopy, size-exclusion chromatography and GPC/MALLS. 71 ± 3% of fluorescence remained in the >5K MWCO fraction; this fraction showed …

Acquisition De Modèles Pour L’Étude De L’Absorption Percutanée Des Substances Chimiques : Cellules De Diffusion À Flux Continu, Claude Viau, Suzanne Leroux, Ross Thuot, Sophie Lim

Rapports de recherche scientifique

Dans les milieux de travail où des substances chimiques sont utilisées, celles-ci peuvent se retrouver dans l’air. Les employés peuvent donc y être exposés par le fait de la respiration. C’est d’ailleurs pour ça que le règlement sur la santé et la sécurité du travail donne des valeurs limites d’exposition dans l’air pour près de 700 substances chimiques. Mais il est aussi possible d’être exposé par le contact des substances avec la peau. Quand on veut savoir à quel point un travailleur peut absorber des substances dans son organisme de cette manière, on doit savoir trois choses principales :

• la …

Development And Recycling Of Novel Arsenic Removal Technology, Morgan Jones

Mahurin Honors College Capstone Experience/Thesis Projects

As of 2006, the U.S. Environmental Protection Agency (EPA) changed the Maximum Contaminant Level (MCL) for arsenic from 50 parts per billion (ppb), to 10ppb because of links to cancer. Current remediation technologies are expensive; therefore, this change will result in increased economic pressure on rural communities with high levels of arsenic in their drinking water. Lowering of the standard has spurred the development of a novel remediation technology that has shown the ability to reduce arsenic in drinking water at the source, with the added benefit of low-cost disposal of a stable and benign waste product in ordinary landfills. …

The Influence Of Citrate, Maltolate And Fluoride On The Gastrointestinal Absorption Of Aluminum At A Drinking Water-Relevant Concentration: A 26Al And 14C Study, Yuzhao Zhou, Wesley R. Harris, Robert A. Yokel

Pharmaceutical Sciences Faculty Publications

The objectives were to test the null hypotheses that (1) citrate, maltolate, and fluoride do not significantly influence oral Al bioavailability, C_max or T_max at an Al dose relevant to drinking water exposure; and (2) Al citrate and maltolate are absorbed intact from the gastrointestinal tract. Male Fisher rats were given 1 ml of solution intra-gastrically containing 1 nCi ²⁶Al (65 nmol total Al) as the Al³⁺ ion, or as complexes with ¹⁴C-citrate, ¹⁴C-maltolate or fluoride, during concurrent ²⁷Al iv infusion. Blood was repeatedly collected for serum ²⁶Al, total Al and ^{14 …}

Occurrence And Biological Effect Of Exogenous Steroids In The Elkhorn River, Nebraska, Usa, Alan S. Kolok, Daniel D. Snow, Satomi Kohno, Marlo K. Sellin, Louis J. Guillette Jr.

Biology Faculty Publications

Recent studies of surface waters in North America, Japan, and Europe have reported the presence of steroidogenic agents as contaminants. The current study has three objectives: 1) to determine if steroidogenic compounds are present in the Elkhorn River, 2) to determine if sediments collected from the Elkhorn River can act as a source of steroidogenic compounds to aquatic organisms, and 3) to determine if site-specific biological effects are apparent in the hepatic gene expression of fathead minnows. Evidence was obtained using three approaches: 1) deployment of polar organic chemical integrative samplers (POCIS), 2) deployment of caged fathead minnows, and 3) …

Lead-Contaminated Candies In Southern Nevada, Shawn Gerstenberger, Glenn Savage, Clayton Sellers, Keith Zupnik, Emmanuel C. Gorospe

Environmental & Global Health Faculty Research

Lead-contaminated candies from Latin America are beginning to gain attention in the public media1,2 and in the medical literature.3–5 These candies come from a number of sources and are manufactured outside Food and Drug Administration regulatory control. In 2005, we sampled 50 imported Latin American candies sold in Southern Nevada. A total of 20 (40%) tested positive with an average lead content of 1.46  0.27 mg/kg in the candies’ wrappers and straws, based on standard Graphite Furnace Atomic Absorption Spectrophotometry methodology. Given these results, the Southern Nevada Health District issued a cease-and-desist order on February 13, 2006, to local …

The Status Of Childhood Lead Poisoning And Prevention In Nevada, Usa, Anne Rothweiler, Elena E. Cabb, Shawn Gerstenberger

Environmental & Global Health Faculty Research

One of the first steps in addressing the problem of childhood lead poisoning is to identify the possible sources of exposure in specific communities and target high-risk populations with appropriate interventions. Due to several factors, such as lack of funding and lack of blood lead reporting, little information exists regarding the occurrence of childhood lead poisoning and the prevalence of potential exposure sources in the state of Nevada. Following the recent establishment of a Nevada-based Lead Poisoning Program, we compiled the most current information available on Nevadans, and use this knowledge to suggest future research objectives and outreach activities for …

Landholder Information For The Safe Use And Management Of Strychnine For Emu Control, Renee Donovan, David Goodall

Biosecurity published reports

Farmnote 34/2003 - Guide to safe use of strychnine poison for emu control included.

Strychnine is a highly poisonous substance that is used in Western Australia for the control of Wild Dogs and Emus. Its use is restricted by law.

This manual outlines your roles and responsibilities in regard to Strychnine use for emu control. In particular this manual outlines the essential information you need to know in regard to:

• The legislative requirements for Strychnine control in Western Australia
• The properties and mode of action of Strychnine
• How to apply to have a strychnine emu baiting program carried out on …

Landholder Information For The Safe Use And Management Of Strychnine For Wild Dog Traps, Renee Donovan, David Goodall

Biosecurity published reports

Farmnote 33/2003 - Guide to the safe use of strychnine for jawed traps is included.

Strychnine is a highly poisonous substance that is used in Western Australia for the control of Wild Dogs and Emus. Its use is restricted by law.

This manual outlines your roles and responsibilities for using and managing Strychnine for Wild Dog control. In particular, this manual outlines the essential information you need to know in regard to:

• The legislative requirements for Strychnine control in Western Australia
• The properties and mode of action of Strychnine « How to lodge an application to use Strychnine
• How to …

Landholder Information For The Safe Use And Management Of 1080, Renee Donovan, David Goodall

Biosecurity published reports

This manual outlines your roles and responsibilities for using and managing 1080. In particular this manual outlines the essential information you need to know in regard to:

• The legislative requirements for 1080 control in Western Australia
• The properties and mode of action of 1080
• How to lodge an application to lay 1080 baits How to safely store and transport 1080
• The procedures and notification required to carry out a baiting proposal
• Personal safety, identifying signs of poisoning & effecting appropriate first aid treatment
• Your responsibilities for notifying DAFWA and the Police of any accidents or incidents
• Methods for evaluating the …

Cadmium Toxicity On Arterioles Vascular Smooth Muscle Cells Of Spontaneously Hypertensive Rats, Benny Washington, Shunta Williams, Patrice Armstrong, Charlie Mtshali, John T. Robinson, Elbert L. Myles

Biology Faculty Research

Cadmium (Cd) is frequently used in various industrial applications and is a ubiquitous environmental toxicant, also present in tobacco smoke. An important route of exposure is the circulatory system whereas blood vessels are considered to be main stream organs of Cd toxicity. Our previous results indicate that cadmium chloride (CdCl2) affects mean arterial blood pressure in hypertensive rats. We hypothesized that Cd alters the intracellular calcium transient mechanism, by cadmium-induced stimulation of MAPKs (ERK 1 & 2) which is mediated partially through calcium-dependent PKC mechanism. To investigate this hypothesis, we exposed primary cultures of vascular smooth muscle cells (VSMCs) from …

Smoking, Anemia, And Risk Of Oral Clefts In Utah, Melinda Michelle Moss

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Cigarette smoke contains sufficient carbon monoxide to induce maternal and fetal hypoxia. Hypoxia is a known teratogen, and consequently maternal smoking has been the focus of many studies on adverse birth outcomes, including cleft lip and palate. Current literature of epidemiological studies on smoking and clefts suggests a modest but statistically significant increase in risk of clefting associated with maternal smoking. A biological condition that may also contribute to hypoxia is anemia. Data from the Utah Child and Family Health Study was used to assess the effects of hypoxia-inducing conditions, maternal smoking, anemia, and their interaction, on the risk of …

The Speciation Of Metals In Mammals Influences Their Toxicokinetics And Toxicodynamics And Therefore Human Health Risk Assessment, Robert A. Yokel, Stephen M. Lasley, David C. Dorman

Pharmaceutical Sciences Faculty Publications

Chemical form (i.e., species) can influence metal toxicokinetics and toxicodynamics and should be considered to improve human health risk assessment. Factors that influence metal speciation (and examples) include: (1) carrier-mediated processes for specific metal species (arsenic, chromium, lead and manganese), (2) valence state (arsenic, chromium, manganese and mercury), (3) particle size (lead and manganese), (4) the nature of metal binding ligands (aluminum, arsenic, chromium, lead, and manganese), (5) whether the metal is an organic versus inorganic species (arsenic, lead, and mercury), and (6) biotransformation of metal species (aluminum, arsenic, chromium, lead, manganese and mercury). The influence of speciation on metal …

A Broad-Spectrum Mer Operon In A Multi-Drug Resistant Strain Of The Fish Pathogen, Aeromonas Salmonicida, Erin Parry

Honors Theses

Aeromonas salmonicida AS03, a potential fish pathogen, was isolated from Atlantic salmon, Salmo salar, in 2003. This strain was found to be resistant to ≥1000 mM HgCl2 and ≥32 mM phenylmercuric acetate as well as multiple antimicrobials. Mercury (Hg) and antibiotic resistance genes are often located on the same mobile genetic elements, so the genetic determinants of both resistances and the possibility of horizontal gene transfer were examined. Specific PCR primers were used to amplify and sequence distinctive regions of the mer operon. A. salmonicida AS03 was found to have a pDU1358-like broad-spectrum mer operon, containing merB as well as …

Chemical Constitutents And Cytotoxicity Of Some Tanzanian Wild Mushrooms, V. Nyigo, L. D. Baraza, M. H. H. Nkunya, S. J. M. Mdachi, C. C. Joseph, A. Waziri

Tanzania Journal of Science

The sterol ergosterol and ergosta-4,22-diene-3β,7α-diol, together with 4-hydroxybenzaldehyde were isolated from the mushroom species Polyporus molluscensis, Cantharellus isabelinus, C. symoensii and a Podaxis species. Their structures were established on the basis of spectroscopic data. The ethanol extracts of mushroom samples of Agaricus sp. and Termitomyces letestui also showed cytotoxicity against the brine shrimp larvae.

Differences In Pah Tolerance Between Capitella Species: Underlying Biochemical Mechanisms, Lis Bach, Annemette Palmqvist, Lene Juel Rasmussen, Valery E. Forbes

Valery Forbes Publications

The polychaete Capitella capitata consists of a species complex within which differences in tolerance to tox­icants have been observed. For example, it has been shown that Capitella sp. S is more sensitive (e.g., in terms of survival, growth and reproduction) to PAH and other stressors than the more opportunistic Capi­tella sp. I, which is able to take up and biotransform the PAH fluoranthene (Flu). In the present study, an in­vestigation was performed to examine whether differences in tolerance between Capitella species sp. I and sp. S are due to differences in biotransformation, measured as the amount of Flu-metabolites produced by …