Medical Toxicology Commons^™

The Intersection Of Herbicide Policy, Exposure, And Health At The University Of Connecticut, Katherine Hayward

Honors Scholar Theses

Pesticides play an extremely complicated role in our everyday lives. From the water you use to make your coffee, to the breastmilk your neighbor provides for their child, to the lake your dog swims in, chemical pesticides or their byproducts have been found in nearly every corner of our lives. The chemicals used in synthetic herbicides, a subcategory of pesticides, have far reaching negative impacts on human health, biodiversity, and water quality. Despite there being numerous published studies on the relationships between pesticide exposures and health, there is still ongoing discord and controversy surrounding their role in our lives. After …

Differential Transcriptional Alterations In Detoxification Genes In Parkinson’S Disease In Egypt, Nourhan Shebl

Theses and Dissertations

PD is the most common motor neurodegenerative disease worldwide. The underlying cause of PD is still unknow, owingthis to the complexity of the disease. Often, genetics and environmental factors are collaborating in the initiation of the disease. Despite the diversity of its genetical and environmental profiles, the Egyptian population is one of the mostunderrepresented population in terms of PD research. In this study, we investigated PD through various perspectives tohighlight the complexity of the disease in Egypt, taking into consideration the diversity of the Egyptian population. We recruited PD patients and reference controls from 4 governorates: Cairo, Giza, Alexandria, and …

Investigating The Role Of The Hedgehog Pathway In Connection To Atrazine Endocrine Disruption, Anusha Kv Lakshmi Dharmavathi

The Journal of Purdue Undergraduate Research

No abstract provided.

Micro-Rna Analysis Of Extracellular Vesicles Secreted By Alveolar Macrophages And Epithelial Cells In Response To Cadmium, Anisha Bhakta

Biotechnology Theses

Inhalation of cadmium (Cd) has been an environmental health concern with the increase in industrial activities and smoking. Cd exposure is known to affect several organs such as lungs, kidneys, and liver. In this study, we wanted to understand if Cd inhalation exposure can affect the lungs and other organs in the body. Exosomes are extracellular vesicles secreted by all living cells and are known to carry toxicants between organs. We investigated whether Cd exposure could affect exosome biogenesis and their composition. Cd exposure did not affect the viability of A549, a lung epithelial cell line and macrophages derived from …

Sub-Region Based Radiomics Analysis For Survival Prediction In Oesophageal Tumours Treated By Definitive Concurrent Chemoradiotherapy, Congying Xie, Pengfei Yang, Xuebang Zhang, Lei Xu, Xiaoju Wang, Xiadong Li, Luhan Zhang, Ruifei Xie, Ling Yang, Zhao Jing, Hongfang Zhang, Lingyu Ding, Yu Kuang, Tianye Niu, Shixiu Wu

Health Physics & Diagnostic Sciences Faculty Publications

Background: Evaluating clinical outcome prior to concurrent chemoradiotherapy remains challenging for oesophageal squamous cell carcinoma (OSCC) as traditional prognostic markers are assessed at the completion of treatment. Herein, we investigated the potential of using sub-region radiomics as a novel tumour biomarker in predicting overall survival of OSCC patients treated by concurrent chemoradiotherapy. Methods: Independent patient cohorts from two hospitals were included for training (n = 87) and validation (n = 46). Radiomics features were extracted from sub-regions clustered from patients' tumour regions using K-means method. The LASSO regression for ‘Cox’ method was used for feature selection. The survival prediction model …

Improving Access To Clean Water In Rural Ecuador: The Connection Between Willingness To Pay And Population Health, Micalea Leaska

Capstone Collection

Climate change is affecting social and environmental determinants of health through access to safe drinking water, safely managed sanitation systems, and access to health care services and the ability for individuals to break free from unsuitable circumstances. Ecological disturbances such as those caused by climate change can cause a shift in host vectors or a change in habitat that results in a greater likelihood of the pathogen coming in contact with humans. Water, sanitation, and hygiene (WASH) services and their accessibility to populations can directly impact a community’s vulnerability to diseases and limiting factors to increase economic growth. If rural …

A Longitudinal Study Of Peripubertal Serum Organochlorine Concentrations And Semen Parameters In Young Men: The Russian Children's Study, Lidia Minguez-Alarcon, Oleg Sergeyev, Jane S. Burns, Paige L. Williams, Mary M. Lee, Susan A. Korrick, Luidmila Smigulina, Boris Revich, Russ Hauser

Mary M. Lee

BACKGROUND: Exposures to endocrine disrupting chemicals during critical phases of testicular development may be related to poorer semen parameters. However, few studies have assessed the association between childhood organochlorine (OC) exposure and adult semen parameters.

OBJECTIVE: We examined whether peripubertal serum OC concentrations are associated with semen parameters among young Russian men.

METHODS: From 2003 to 2005, 516 boys were enrolled at age 8-9 years and followed for up to ten years. Serum OCs were measured in the enrollment samples using high-resolution mass spectrometry. At age 18-19 years, 133 young men provided one or two semen samples (256 samples) collected …

Toxic Environmental Exposures And Kidney Health In Children., Darcy K. Weidemann, Virginia M. Weaver, Jeffrey J. Fadrowski

Manuscripts, Articles, Book Chapters and Other Papers

High-level exposures to a number of agents are known to have direct nephrotoxic effects in children. A growing body of literature supports the hypothesis that chronic, relatively low-level exposure to various nephrotoxicants may also increase the risk for chronic kidney disease (CKD) or accelerate its progression. In this review we highlight several environmental nephrotoxicants and their association with CKD in children and adolescents. We also discuss unique epidemiological challenges in the use of kidney biomarkers in environmental nephrotoxicology.

A Modular One-Generation Reproduction Study As A Flexible Testing System For Regulatory Safety Assessment, Richard Vogel, Troy Seidle, Horst Spielmann

Troy Seidle, PhD

The European Union’s Registration, Evaluation and Authorisation of Chemicals (REACH) legislation mandates testing and evaluation of approximately 30,000 existing substances within a short period of time, beginning with the most widely used “high production volume” (HPV) chemicals. REACH testing requirements for the roughly 3000 HPV chemicals specify three separate tests for reproductive toxicity: two developmental toxicity studies on different animal species (OECD Test Guideline 414) and a two-generation reproduction toxicity study (OECD TG 416). These studies are highly costly in both economic and animal welfare terms. OECD TG 416 is a fertility study intended to evaluate reproductive performance of animals …

Stratified Meta-Analysis To Examine Data Biases In Lung Cancer Studies Of Refinery Workers, Sherman Selix

Yale Day of Data

Petroleum refineries employ a variety of workers who historically experienced different potentials for asbestos exposure depending on job tasks. Associations between petroleum refinery work and lung cancer related to occupational asbestos exposure have been quantified among various locations, corporations, and time periods. To combine the data from several individual refinery studies and examine an overall effect, a systematic review and stratified meta-analysis was employed. Using set search terms among four databases, 112 potential publications were identified, of which 29 qualified for meta-analysis. Risk estimates and confidence intervals were extracted from these publications to construct four separate datasets. Inverse variance weighting …

Genetic Modification Of The Association Between Peripubertal Dioxin Exposure And Pubertal Onset In A Cohort Of Russian Boys, Olivier Humblet, Susan A. Korrick, Paige L. Williams, Oleg Sergeyev, Claude Emond, Linda S. Birnbaum, Jane S. Burns, Larisa Altshul, Donald G. Patterson Jr., Wayman E. Turner, Mary M. Lee, Boris Revich, Russ Hauser

Mary M. Lee

BACKGROUND: Exposure to dioxins has been associated with delayed pubertal onset in both epidemiologic and animal studies. Whether genetic polymorphisms may modify this association is currently unknown. Identifying such genes could provide insight into mechanistic pathways. This is one of the first studies to assess genetic susceptibility to dioxins. OBJECTIVES: We evaluated whether common polymorphisms in genes affecting either molecular responses to dioxin exposure or pubertal onset influence the association between peripubertal serum dioxin concentration and male pubertal onset. METHODS: In this prospective cohort of Russian adolescent boys (n = 392), we assessed gene-environment interactions for 337 tagging single-nucleotide polymorphisms …

Early Chronic Low-Level Lead Exposure Produces Glomerular Hypertrophy In Young C57bl/6j Mice, Christina Sobin, John Basgen

Christina Sobin, Ph.D.

Early chronic lead exposure continues to pose serious health risks for children, particularly those living in lower socioeconomic environments. This study examined effects on developing glomeruli in young C57BL/6J mice exposed to low (30 ppm), higher (330 ppm) or no lead via dams’ drinking water from birth to sacrifice on post-natal day 28. Low-level lead exposed mice [BLL mean (SD); 3.19 (0.70) µg/dL] had an increase in glomerular volume but no change in podocyte number compared to control mice [0.03 (0.01) µg/dL]. Higher-level lead exposed mice [14.68 (2.74) µg/dL] had no change in either glomerular volume or podocyte number. The …

Diet And Toenail Arsenic Concentrations In A New Hampshire Population With Arsenic-Containing Water, Kathryn L. Cottingham, Roxanne Karimi, Joann F. Gruber, M Scot Zens, Vicki Sayarath, Carol L. Folt, Tracy Punshon, J. Steven Morris, Margaret R. Karagas

Dartmouth Scholarship

Background: Limited data exist on the contribution of dietary sources of arsenic to an individual's total exposure, particularly in populations with exposure via drinking water. Here, the association between diet and toenail arsenic concentrations (a long-term biomarker of exposure) was evaluated for individuals with measured household tap water arsenic. Foods known to be high in arsenic, including rice and seafood, were of particular interest.

Methods: Associations between toenail arsenic and consumption of 120 individual diet items were quantified using general linear models that also accounted for household tap water arsenic and potentially confounding factors (e.g., age, caloric intake, sex, smoking) …

Microglial Disruption In Young Mice With Early Chronic Exposure To Lead, Christina Sobin, Mayra Flores Montoya, Natali Parisi, Tanner Schaub, Miguel Cervantes, Rodrigo Armijos

Christina Sobin, Ph.D.

The mechanisms by which early chronic lead (Pb) exposure alters brain development have not been identified. We examined neuroimmune system effects in C57BL/6J mice with Pb exposure, including levels that may be common among children in lower socioeconomic income environments. Pups were exposed via dams’ drinking water from birth to post-natal day 28 to low, high or no Pb conditions. We compared gene expression of neuroinflammatory markers (study 1); and microglial mean cell body volume and mean cell body number in dentate gyrus, and dentate gyrus volume (study 2). Blood Pb levels in exposed animals at sacrifice (post-natal day 28) …

Associations Between Cadmium Exposure And Neurocognitive Test Scores In A Cross-Sectional Study Of Us Adults, Timothy Ciesielski, David C. Bellinger, Joel Schwartz, Russ Hauser, Robert O. Wright

Dartmouth Scholarship

Background: Low-level environmental cadmium exposure and neurotoxicity has not been well studied in adults. Our goal was to evaluate associations between neurocognitive exam scores and a biomarker of cumulative cadmium exposure among adults in the Third National Health and Nutrition Examination Survey (NHANES III).

Methods: NHANES III is a nationally representative cross-sectional survey of the U.S. population conducted between 1988 and 1994. We analyzed data from a subset of participants, age 20–59, who participated in a computer-based neurocognitive evaluation. There were four outcome measures: the Simple Reaction Time Test (SRTT: visual motor speed), the Symbol Digit Substitution Test (SDST: attention/perception), …

Associations Between Toenail Arsenic Concentration And Dietary Factors In A New Hampshire Ppopulation, Joann F. Gruber, Margaret R. Karagas, Diane Gilbert-Diamond, Pamela J. Bagley, M Scot Zens, Vicki Sayarath, Tracy Punshon, J Steven Morris, Kathryn L. Cottingham

Dartmouth Scholarship

Background: Dietary factors such as folate, vitamin B12, protein, and methionine are important for the excretion of arsenic via one-carbon metabolism in undernourished populations exposed to high levels of arsenic via drinking water. However, the effects of dietary factors on toenail arsenic concentrations in well-nourished populations exposed to relatively low levels of water arsenic are unknown.

Methods: As part of a population-based case-control study of skin and bladder cancer from the USA, we evaluated relationships between consumption of dietary factors and arsenic concentrations in toenail clippings. Consumption of each dietary factor was determined from a validated food frequency questionnaire. We …

Rice Consumption Contributes To Arsenic Exposure In Us Women, Diane Gilbert-Diamond, Kathryn L. Cottingham, Joann F. Gruber, Tracy Punshon, Vicki Sayarath, A. Jay Gandolfi, Emily R. Baker, Brian P. Jackson, Carol L. Folt, Margaret R. Karagas

Dartmouth Scholarship

Emerging data indicate that rice consumption may lead to potentially harmful arsenic exposure. However, few human data are available, and virtually none exist for vulnerable periods such as pregnancy. Here we document a positive association between rice consumption and urinary arsenic excretion, a biomarker of recent arsenic exposure, in 229 pregnant women. At a 6-mo prenatal visit, we collected a urine sample and 3-d dietary record for water, fish/seafood, and rice. We also tested women's home tap water for arsenic, which we combined with tap water consumption to estimate arsenic exposure through water. Women who reported rice intake (n …

Identifying And Reducing Lead Exposure Associated With The Use Of Cultural Practices In Southern Nevada Hispanic Communities, Maria Castillo-Couch

UNLV Theses, Dissertations, Professional Papers, and Capstones

Despite large amounts of national data on lead and childhood lead poisoning, the status of childhood lead exposure in Nevada as a result of the use of cultural practices in the Hispanic population is unknown. The influx of immigrant Hispanic populations to Nevada, their low education level, the high number of them who are living in poverty present an increased risk for children to be exposed to lead through the use of imported consumables, home remedies and alternative medicine (i.e., healers/ sobadores).

A 61-question survey collected data from Hispanics over 18 years of age who have or take care …

Δ-Aminolevulinic Acid Dehydratase Single Nucleotide Polymorphism 2 And Peptide Transporter 2*2 Haplotype May Differentially Mediate Lead Exposure In Male Children, Christina Sobin, Natali Parisi, Tanner Schaub, Marisela Gutierrez, Alma Ortega

Christina Sobin, Ph.D.

Child low-level lead (Pb) exposure is an unresolved public health problem and an unaddressed child health disparity. Particularly in cases of low-level exposure, source removal can be impossible to accomplish, and the only practical strategy for reducing risk may be primary prevention. Genetic biomarkers of increased neurotoxic risk could help to identify small subgroups of children for early intervention. Previous studies have suggested that, by way of a distinct mechanism, d-aminolevulinic acid dehydratase single nucleotide polymorphism 2 (ALAD2) and/or peptide transporter 2*2 haplotype (hPEPT2*2) increase Pb blood burden in children. Studies have not yet examined whether sex mediates the effects …

Mycotoxins In Grains – Causes, Prevention And Control, Hester F. Vismer

INTSORMIL Presentations

Discusses mycotoxins, their effect on grain, mitigation considerations, and resulting human toxicology.

A Bland–Altman Comparison Of The Lead Care® System And Inductively Coupled Plasma Mass Spectrometry For Detecting Low-Level Lead In Child Whole Blood Samples, Christina Sobin, Tanner Schaub, Natali Parisi, Eva De La Riva

Christina Sobin, Ph.D.

Chronic childhood lead exposure, yielding blood lead levels consistently below 10 μg/dL, remains a major public health concern. Low neurotoxic effect thresholds have not yet been established. Progress requires accurate, efficient, and cost-effective methods for testing large numbers of children. The LeadCare® System (LCS) may provide one ready option. The comparability of this system to the “gold standard” method of inductively coupled plasma mass spectrometry (ICP-MS) for the purpose of detecting blood lead levels below 10 μg/dL has not yet been examined. Paired blood samples from 177 children ages 5.2–12.8 years were tested with LCS and ICP-MS. Triplicate repeat tests …

An Evaluation Of Plastic Toys For Lead Contamination In Day Care Centers In The Las Vegas Valley, Joseph Alan Greenway

UNLV Theses, Dissertations, Professional Papers, and Capstones

The harmful effect of childhood exposure to environmental lead continues to be a major health concern. This study examined lead contamination within the plastic of children's toys. It was also hypothesized that the use of lead as a stabilizer would result in higher incidents of elevated lead (> 600 ppm) in polyvinyl chloride plastics (PVC) than non-PVC plastics. It was also hypothesized that, due to the use lead chromate, yellow toys would have higher incidents of elevated lead (> 600 ppm) than toys of other colors. Toy samples were limited to those found in day care centers in Las Vegas, …

Suppression Of Peroxisomal Enzyme Activities And Cytochrome P450 4a Isozyme Expression By Congeneric Polybrominated And Polychlorinated Biphenyls, Larry W. Robertson, Isabelle Berberian, Tim Borges, Li-Chuan Chen, Ching K. Chow, Howard P. Glauert, Johannes G. Filser, Helmut Thomas

Toxicology and Cancer Biology Faculty Publications

The purpose of this study was to determine the effects of PCBs and PBBs on peroxisome proliferator-activated receptor-alpha-(PPARalpha-) associated enzyme activities or protein levels. Male Sprague-Dawley rats were administered a single IP injection (150 mu mol/kg) of either 3,3',4,4'-tetrabromobiphenyl, 3,3',4,4'-tetrachlorobiphenyl, 3,3',5,5'-tetrabromobiphenyl, 2',3,3',4,5-pentachlorobiphenyl, 3,3',4,4',5-pentachlorobiphenyl, 2,2',3,3',5,5'-hexachlorobiphenyl, or 3,3',4,4',5,5'-hexabromobiphenyl in corn oil (10 ml/kg). One week later, the activities of catalase, peroxisomal fatty acyl-CoA oxidase, and peroxisomal beta-oxidation as well as cytochrome P450 4A (CYP4A) protein content were determined in subcellular liver fractions. None of the peroxisomal enzyme activities were significantly increased by any of the halogenated biphenyl congeners tested. Except for minor …

Reduction In Urinary Arsenic With Bottled-Water Intervention, Arun B. Josyula, Hannah Mcclellen, Tracy A. Hysong, Margaret Kurzius-Spencer, Gerald S. Poplin, Stefan Stürup, Jefferey L. Burgess

Dartmouth Scholarship

The study was conducted to measure the effectiveness of providing bottled water in reducing arsenic exposure. Urine, tap-water and toenail samples were collected from non-smoking adults residing in Ajo (n=40) and Tucson (n=33), Arizona, USA. The Ajo subjects were provided bottled water for 12 months prior to re-sampling. The mean total arsenic (microg/L) in tap-water was 20.3+/-3.7 in Ajo and 4.0+/-2.3 in Tucson. Baseline urinary total inorganic arsenic (microg/L) was significantly higher among the Ajo subjects (n=40, 29.1+/-20.4) than among the Tucson subjects (n=32, 11.0+/-12.0, p<0.001), as was creatinine-adjusted urinary total inorganic arsenic (microg/g) (35.5+/-25.2 vs 13.2+/-9.3, p<0.001). Baseline concentrations of arsenic (microg/g) in toenails were also higher among the Ajo subjects (0.51+/-0.72) than among the Tucson subjects (0.17+/-0.21) (p<0.001). After the intervention, the mean urinary total inorganic arsenic in Ajo (n=36) dropped by 21%, from 29.4+/-21.1 to 23.2+/-23.2 (p=0.026). The creatinine-adjusted urinary total inorganic arsenic and toenail arsenic levels did not differ significantly with the intervention. Provision of arsenic-free bottled water resulted in a modest reduction in urinary total inorganic arsenic.

Do Recent Data From The Seychelles Islands Alter The Conclusions Of The Nrc Report On The Toxicological Effects Of Methylmercury?, Alan H. Stern, Joseph L. Jacobson, Louise Ryan, Thomas A. Burke

Wayne State University Associated BioMed Central Scholarship

Abstract

In 2000, the National Research Council (NRC), an arm of the National Academy of Sciences, released a report entitled, "Toxicological Effects of Methylmercury." The overall conclusion of that report was that, at levels of exposure in some fish- and marine mammal-consuming communities (including those in the Faroe Islands and New Zealand), subtle but significant adverse effects on neuropsychological development were occurring as a result of in utero exposure. Since the release of that report, there has been continuing discussion of the public health relevance of current levels of exposure to Methylmercury. Much of this discussion has been linked to …

Poison Plants In The Garden, T E H Aplin

Journal of the Department of Agriculture, Western Australia, Series 4

SOME 18 commonly grown garden plants are known to be toxic and many local home gardens have five or six of them.

Several other species can cause skin ailments.