Pharmacology, Toxicology and Environmental Health | Open Access Articles

Accuracy Of Therapeutic Drug Monitoring In Vancomycin And The Pharmacist Role: A Retrospective Case-Series, Kateryna Parkhomenko

Senior Theses

Vancomycin is a mainstay of therapy for treating virulent and resistant infections, especially methicillin-resistant Staphylococcus aureus (MRSA). However, vancomycin requires therapeutic drug monitoring (TDM) for optimal dosing and treatment. This requires pharmacists to calculate a dosing regimen that correlates to appropriate goal vancomycin concentrations in the blood. Dosing vancomycin can be difficult, as it varies on a patient’s weight, renal function, age, etc. Doses may have to be adjusted in response to out-of-range concentrations, which requires further pharmacy calculations. Inaccurate dosing poses a risk to patient safety and places a resource and time burden on pharmacists. If vancomycin dosing methods …

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Superfund And Society Benumbed: An In-Depth Look At Environmental Justice In South Carolina, Sydney A. Hampton

Senior Theses

This thesis investigates the relationship between superfund sites in minority communities and their public health through the lens of social vulnerability. Various demographic parameters were used to assess the risk associated with minority communities and exposure to hazardous waste. After investigating the history of the Environmental Justice movement, three superfund sites of interest in South Carolina, and demographic and public health data; each community was analyzed to determine association between exposure to hazardous waste and minority status. Each examined community exhibited characteristics contributing to heightened social vulnerability, potentially causing increased susceptibility to negative health outcomes from exposure to hazardous waste.

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Dependence On Humidity And Aerosol Composition Of The Gas-Particle Partitioning Of Weakly And Moderately Polar Vocs, Jeonghyeon Ahn, Guiying Rao, Eric P. Vejerano

Faculty Publications

Volatile organic compounds (VOCs) dominate the class of pollutants that accumulate in the atmosphere and indoors. Assessing the gas-particle partitioning of VOCs is important to determine their fate, transport, and adverse health impacts. This work is a companion to our earlier study on the temperature dependence of VOC partitioning. Here, we report our measurement of the gas-particle partition coefficient (Kp) for weakly polar (trichloroethylene, TCE) and moderately polar (n-butanol, n-BuOH) VOCs under varying relative humidity (RH) levels onto organic and inorganic aerosols. Kp of TCE was four to five orders of magnitude lower than those …

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Environmentally Persistent Free Radicals As Sources Of Pops, Eric P. Vejerano, Jeonghyeon Ahn, Junaid Latif, Mustafa Mamun

Faculty Publications

Environmentally persistent free radicals (EPFRs) are a new class organic pollutant sharing some of the attributes of persistent organic pollutants (POPs). This opinion/short review aims to describe the properties of EPFRs that merit their recognition as an additional and potentially significant source of POPs. EPFRs are ubiquitous in diverse environments because of multiple factors: (1) organic precursors from anthropogenic, biogenic, and other natural emission sources are abundant; multiple mechanisms in PM and soils form (2) EPFRs; and (3) EPFRs are stable and persist for a long time, thereby, accumulate in the environment and potentially transported long range. The hazards of …

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Nanoantibiotics: Functions And Properties At The Nanoscale To Combat Antibiotic Resistance, M. Mustafa Mamun, Adeola Julian Sorinolu, Mariya Munir, Eric P. Vejerano

Faculty Publications

One primary mechanism for bacteria developing resistance is frequent exposure to antibiotics. Nanoantibiotics (nAbts) is one of the strategies being explored to counteract the surge of antibiotic resistant bacteria. nAbts are antibiotic molecules encapsulated with engineered nanoparticles (NPs) or artificially synthesized pure antibiotics with a size range of ≤100 nm in at least one dimension. NPs may restore drug efficacy because of their nanoscale functionalities. As carriers and delivery agents, nAbts can reach target sites inside a bacterium by crossing the cell membrane, interfering with cellular components, and damaging metabolic machinery. Nanoscale systems deliver antibiotics at enormous particle number concentrations. …

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A Method To Measure The Partitioning Coefficient Of Volatile Organic Compounds In Nanoparticles, Guiying Rao, Jeonghyeon Ahn, Abigail Evans, Michelle Casey, Eric P. Vejerano

Faculty Publications

The partitioning behavior of volatile organic compounds (VOCs) into nanoparticles is less studied compared to those of semivolatile organic compounds (SVOCs) because of the lower concentration of the VOCs that is expected to partition into particles. One challenge in measuring the accurate partition coefficient of VOCs is quantifying their low mass fraction that sorbed on nanoparticles and differentiating them from the high VOC concentrations present in the gas-phase. Systematically characterizing the partitioning coefficient at a specific environmental condition is also difficult when sampling in the field. During field sampling, thermal and non-thermal issues such as sampling artifacts and non-equilibrium conditions …

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A Letter To Reconsider The Conditions For Testing Decontaminated N95 Respirators For Emergency Reuse To Address Shortage, Eric P. Vejerano, Jeonghyeon Ahn

Faculty Publications

The battle with COVID-19 pandemic has resulted in the shortage of personal protective equipment, particularly, N95 respirators. Healthcare workers who reused N95 respirators may resort to unproven methods of cleaning/sterilization that can severely compromise the respirators’ filtration efficiency. A recently issued guideline will test decontaminated N95 respirators against particles with a median diameter of 0.075 ± 0.020 µm at a flow rate of 85 L min–1. For emergency reuse, these conditions may be too stringent. N95 respirators tested at this flow rate had predicted efficiencies of < 69%, assuming complete degradation of their electrostatic coating. Experimental efficiencies were ~15% lower. For emergency reuse, we recommend to either adjust the flow rate closer to normal breathing, or the size of the test particle should reflect that of virus-laden respiratory aerosols (~> 0.5 µm). By reconsidering the test conditions, a substantial fraction of used/decontaminated respirators can …

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Influenza Virus Infectivity Is Retained In Aerosols And Droplets Independent Of Relative Humidity, Karen A. Kormuth, Kaisen Lin, Aaron J. Prussin, Eric P. Vejerano, Andrea J. Tiwari, Steve S. Cox, Micheal M. Myerburg, Seema S. Lakdawala, Linsey C. Marr

Faculty Publications

Pandemic and seasonal influenza viruses can be transmitted through aerosols and droplets, in which viruses must remain stable and infectious across a wide range of environmental conditions. Using humidity-controlled chambers, we studied the impact of relative humidity on the stability of 2009 pandemic influenza A(H1N1) virus in suspended aerosols and stationary droplets. Contrary to the prevailing paradigm that humidity modulates the stability of respiratory viruses in aerosols, we found that viruses supplemented with material from the apical surface of differentiated primary human airway epithelial cells remained equally infectious for 1 hour at all relative humidities tested. This sustained infectivity was …

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Aerosol Microdroplets Exhibit A Stable Ph Gradient, Haoran Wei, Eric P. Vejerano, Weinan Leng, Qishen Haung, Marjorie R. Willner, Linsey C. Marr, Peter J. Vikesland

Faculty Publications

Suspended aqueous aerosol droplets (<50 μm) are microreactors for many important atmospheric reactions. In droplets and other aquatic environments, pH is arguably the key parameter dictating chemical and biological processes. The nature of the droplet air/ water interface has the potential to significantly alter droplet pH relative to bulk water. Historically, it has been challenging to measure the pH of individual droplets because of their inaccessibility to conventional pH probes. In this study, we scanned droplets containing 4-mercaptobenzoic acid–functionalized gold nanoparticle pH nanoprobes by 2D and 3D laser confocal Raman microscopy. Using surface-enhanced Raman scattering, we acquired the pH distribution inside approximately 20-μm-diameter phosphate-buffered aerosol droplets and found that the pH in the core of a droplet is higher than that of bulk solution by up to 3.6 pH units. This finding suggests the accumulation of protons at the air/water interface and is consistent with recent thermodynamic model results. The existence of this pH shift was corroborated by the observation that a catalytic reaction that occurs only under basic conditions (i.e., dimerization of 4-aminothiophenol to produce dimercaptoazobenzene) occurs within the high pH core of a droplet, but not in bulk solution. Our nanoparticle probe enables pH quantification through the cross-section of an aerosol droplet, revealing a spatial gradient that has implications for acid-base–catalyzed atmospheric chemistry.

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Physico-Chemical Characteristics Of Evaporating Respiratory Fluid Droplets, Eric P. Vejerano, Linsey C. Marr

Faculty Publications

The detailed physico-chemical characteristics of respiratory droplets in ambient air, where they are subject to evaporation, are poorly understood. Changes in the concentration and phase of major components in a droplet—salt (NaCl), protein (mucin) and surfactant (dipalmitoylphosphatidylcholine)—may affect the viability of any pathogens contained within it and thus may affect the efficiency of transmission of infectious disease by droplets and aerosols. The objective of this study is to investigate the effect of relative humidity (RH) on the physico-chemical characteristics of evaporating droplets of model respiratory fluids. We labelled these components in model respiratory fluids and observed evaporating droplets suspended on …

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Nanotechnology In The Real World: Redeveloping The Nanomaterial Consumer Products Inventory, Marina E. Vance, Todd Kuiken, Eric P. Vejerano, Sean P. Mcginnis, Michael F. Hochella Jr., David Rejeski, Matthew S. Hull

Faculty Publications

To document the marketing and distribution of nano-enabled products into the commercial marketplace, the Woodrow Wilson International Center for Scholars and the Project on Emerging Nanotechnologies created the Nanotechnology Consumer Products Inventory (CPI) in 2005. The objective of this present work is to redevelop the CPI by leading a research effort to increase the usefulness and reliability of this inventory. We created eight new descriptors for consumer products, including information pertaining to the nanomaterials contained in each product. The project was motivated by the recognition that a diverse group of stakeholders from academia, industry, and state/federal government had become highly …

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Toxicity Of Engineered Nanomaterials And Their Transformation Products Following Wastewater Treatment On A549 Human Lung Epithelial Cells, Yanjun Ma, Subbiah Elankumaran, Linsey C. Marr, Eric P. Vejerano, Amy Pruden

Faculty Publications

Here we characterize the toxicity of environmentally-relevant forms of engineered nanomaterials (ENMs), which can transform during wastewater treatment and persist in aqueous effluents and biosolids. In an aerosol exposure scenario, cytotoxicity and genotoxicity of effluents and biosolids from lab-scale sequencing batch reactors (SBRs) to A549 human lung epithelial cells were examined. The SBRs were dosed with nanoAg, nano zero-valent iron (NZVI), nanoTiO2 and nanoCeO2 at sequentially increasing concentrations from 0.1 to 20 mg/L. Toxicities were compared to outputs from SBRs dosed with ionic/bulk analogs, undosed SBRs, and pristine ENMs. Pristine nanoAg and NZVI showed significant cytotoxicity to A549 cells in …

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Characterization Of Particle Emissions And Fate Of Nanomaterials During Incineration, Eric P. Vejerano, Elena C. Leon, Amara L. Holder, Linsey C. Marr

Faculty Publications

As the use of nanotechnology in consumer products continues to grow, it is inevitable that some nanomaterials will end up in the waste stream and will be incinerated. Through laboratory-scale incineration of paper and plastic wastes containing nanomaterials, we assessed their effect on emissions of particulate matter (PM) and the effect of incineration on the nanomaterials themselves. The presence of nanomaterials did not significantly influence the particle number emission factor. The PM size distribution was not affected except at very high mass loadings (10 wt%) of the nanomaterial, in which case the PM shifted toward smaller sizes; such loadings are …

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Full-Text Articles in Pharmacology, Toxicology and Environmental Health

Accuracy Of Therapeutic Drug Monitoring In Vancomycin And The Pharmacist Role: A Retrospective Case-Series, Kateryna Parkhomenko

Senior Theses

Superfund And Society Benumbed: An In-Depth Look At Environmental Justice In South Carolina, Sydney A. Hampton

Senior Theses

Dependence On Humidity And Aerosol Composition Of The Gas-Particle Partitioning Of Weakly And Moderately Polar Vocs, Jeonghyeon Ahn, Guiying Rao, Eric P. Vejerano

Faculty Publications

Environmentally Persistent Free Radicals As Sources Of Pops, Eric P. Vejerano, Jeonghyeon Ahn, Junaid Latif, Mustafa Mamun

Faculty Publications

Nanoantibiotics: Functions And Properties At The Nanoscale To Combat Antibiotic Resistance, M. Mustafa Mamun, Adeola Julian Sorinolu, Mariya Munir, Eric P. Vejerano

Faculty Publications

A Method To Measure The Partitioning Coefficient Of Volatile Organic Compounds In Nanoparticles, Guiying Rao, Jeonghyeon Ahn, Abigail Evans, Michelle Casey, Eric P. Vejerano

Faculty Publications

A Letter To Reconsider The Conditions For Testing Decontaminated N95 Respirators For Emergency Reuse To Address Shortage, Eric P. Vejerano, Jeonghyeon Ahn

Faculty Publications

Influenza Virus Infectivity Is Retained In Aerosols And Droplets Independent Of Relative Humidity, Karen A. Kormuth, Kaisen Lin, Aaron J. Prussin, Eric P. Vejerano, Andrea J. Tiwari, Steve S. Cox, Micheal M. Myerburg, Seema S. Lakdawala, Linsey C. Marr

Faculty Publications

Aerosol Microdroplets Exhibit A Stable Ph Gradient, Haoran Wei, Eric P. Vejerano, Weinan Leng, Qishen Haung, Marjorie R. Willner, Linsey C. Marr, Peter J. Vikesland

Faculty Publications

Physico-Chemical Characteristics Of Evaporating Respiratory Fluid Droplets, Eric P. Vejerano, Linsey C. Marr

Faculty Publications

Nanotechnology In The Real World: Redeveloping The Nanomaterial Consumer Products Inventory, Marina E. Vance, Todd Kuiken, Eric P. Vejerano, Sean P. Mcginnis, Michael F. Hochella Jr., David Rejeski, Matthew S. Hull

Faculty Publications

Toxicity Of Engineered Nanomaterials And Their Transformation Products Following Wastewater Treatment On A549 Human Lung Epithelial Cells, Yanjun Ma, Subbiah Elankumaran, Linsey C. Marr, Eric P. Vejerano, Amy Pruden

Faculty Publications

Characterization Of Particle Emissions And Fate Of Nanomaterials During Incineration, Eric P. Vejerano, Elena C. Leon, Amara L. Holder, Linsey C. Marr

Faculty Publications