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Lead

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Speciation, Distribution, Prediction, And Mobility Of Lead In Urban Soils: A Multiscale Study, Jennifer Bower Jan 2017

Speciation, Distribution, Prediction, And Mobility Of Lead In Urban Soils: A Multiscale Study, Jennifer Bower

Graduate College Dissertations and Theses

Lead (Pb), a trace metal notorious for its impacts on human health, has achieved worldwide environmental dispersal resulting from centuries of use by human society. The toxicity of Pb is governed largely by its mineral form, which is in turn controlled by pH, localized reactivity and soil processes that differ according to soil type, location and Pb source. Given the context of these localized dependencies, or site specificity, efforts to predict Pb toxicity and refine sustainable remediation techniques are most useful when Pb behavior is constrained and predicted within environments with homogeneous conditions, such as a single soil. I evaluated …


Channel Sediment And Mining-Lead Storage In Flat River Creek, Old Lead Belt, Missouri, Ralph Joseph Hill Dec 2016

Channel Sediment And Mining-Lead Storage In Flat River Creek, Old Lead Belt, Missouri, Ralph Joseph Hill

MSU Graduate Theses

Historical mining for lead (Pb) in the Old Lead Belt District introduced large volumes of tailings into nearby streams resulting in the large-scale contamination of channel bed and bar deposits in Big River which drains the southeastern Missouri Ozarks. Tailings pile sites have been remediated so that present contamination sources to the river are primarily from the remobilization of Pb stored in channel and floodplain deposits. This study examined the channel geomorphology and sediment geochemistry of Flat River Creek (FRC), a major tributary to the Big River which drains an area that includes three of the six major mines in …


Influence Of Permeate From Domestic Reverse Osmosis Filters On Lead Corrosion And Leaching From Plastic Pipes, Jyotsna Shrestha May 2016

Influence Of Permeate From Domestic Reverse Osmosis Filters On Lead Corrosion And Leaching From Plastic Pipes, Jyotsna Shrestha

Theses and Dissertations

Reverse Osmosis filters are gaining popularity nowadays, in domestic water supply system, to meet the increasing demand of pure and improved drinking water. There are various types of domestic RO filters with varying sizes, capacities, and treatment stages available. However, there exist a few concerns regarding the RO treatment system. One of the major issues in the quality and distribution of drinking water is the corrosive water that the RO system produces. Therefore, this research herein tends to focus on the corrosive effect of the permeate water on lead metal, as lead is considered a serious problematic drinking water contaminant. …


Identifying Source Of Lead Particles In Floor Dust Using Computer Controlled Scanning Electron Microscope (Ccsem), Joyashree Sarker May 2016

Identifying Source Of Lead Particles In Floor Dust Using Computer Controlled Scanning Electron Microscope (Ccsem), Joyashree Sarker

Earth & Environmental Sciences Dissertations

Identifying the sources of lead (Pb) in indoor dust by analysis of the contents of the dust provides an opportunity to mitigate the source of contamination. In this study, it is hypothesized that in residential properties where there exist the potential for friction surfaces to contribute old lead-based paint to the dust such material can be identified by microscopic examination of the dust. Although old lead-based paint in such circumstances can be implicated, without studying the dust it is impossible to know whether some other contributing source may be important. Exterior soil and dust that potentially can enter the home …


Characterization Of 1, 4, 7-Trithiacyclononane, [9]Anes3 As A Potential Toxic Heavy Metal Chelator, Nahid Bakhtari Jan 2016

Characterization Of 1, 4, 7-Trithiacyclononane, [9]Anes3 As A Potential Toxic Heavy Metal Chelator, Nahid Bakhtari

Student Theses and Dissertations

Toxic heavy metal poisoning with metals including lead, mercury, and cadmium, whether in the environment or through ingestion, remains a persistent problem. Remediation of metal contamination and poisoning has generally been treated with chelating agents that bind metals, rendering them inert, and allow for easier removal. Chelation involves the formation of two or more separate coordinate covalent bonds between a polydentate ligand and a single central atom. However, chelators are not without side effects. Due to the similar size of metal ions and lack of specificity of ligands, chelators can also remove beneficial metals like iron and zinc from the …


An Investigation Of The Uptake, Distribution, And Accumulation Of Lead And Other Trace Elements In Caprine Brain Tissues Using Analytical Atomic Spectrometry, Amy Joanna Steuerwald Jan 2016

An Investigation Of The Uptake, Distribution, And Accumulation Of Lead And Other Trace Elements In Caprine Brain Tissues Using Analytical Atomic Spectrometry, Amy Joanna Steuerwald

Legacy Theses & Dissertations (2009 - 2024)

Exposure to toxic elements and dysregulation of essential elements have been implicated in neurodegenerative disorders. Despite the importance of trace elements in neurological function, little is known regarding their uptake and distribution within brain tissues. Even less is known regarding the impact of toxic metal exposure (i.e., Pb) on endogenous metals within the brain.


Fabrication, Characterization, And Application Of Carbon Nanoparticles For The Detection Of Heavy Metal Ions In Aqueous Media, Aaron Michael Simpson Dec 2015

Fabrication, Characterization, And Application Of Carbon Nanoparticles For The Detection Of Heavy Metal Ions In Aqueous Media, Aaron Michael Simpson

MSU Graduate Theses

This research set out to develop a method for producing Carbon nanoparticles (CNPs) from glycerol and use them to detect Cu2+, Hg2+, and Pb2+ ions in aqueous solution. Three synthesis methods were developed using the following mixtures: (1) glycerol and silica, (2) glycerol, silica, and H3PO4, and (3) glycerol with H3PO4. The structure of the particles was characterized using a variety of spectroscopic techniques. Size distributions were obtained from scanning electron microscopy images. The particles were spherical with average diameters of 66, 58, and 89 nm respectively and believed to consist of a carbon core with carboxylic acid and alcohol …


Source Constraints Of Ore Metals In Mississippi Valley-Type Deposits In Central And Eastern Tennessee Using Pb Isotopes, Austin Moyers May 2015

Source Constraints Of Ore Metals In Mississippi Valley-Type Deposits In Central And Eastern Tennessee Using Pb Isotopes, Austin Moyers

Graduate Theses and Dissertations

The Mississippi Valley-Type (MVT) Central and East Tennessee (TN) Districts contain economically significant lead-zinc deposits that occur in the Early Ordovician carbonates of the Knox Group. Although both districts share similar host rock, have similar temperatures of formation, and typically fill open spaces of collapse breccias or replace their host carbonates, previous studies may suggest that these ores did not form from the same mineralizing fluids and may have different Pb sources. Nu Plasma MC-ICP-MS Pb isotopic analyses on sulfides from Central and East TN were conducted and the metal sources evaluated. Results were plotted on covariation diagrams with respect …


Comparison Of Blood Lead Levels Between Children In An Urban Setting And Children In A Rural Setting, Juan Manuel Alvarez Jan 2015

Comparison Of Blood Lead Levels Between Children In An Urban Setting And Children In A Rural Setting, Juan Manuel Alvarez

Open Access Theses & Dissertations

Environmental heavy metal exposure is a public health problem that is of great concern because it is highly toxic for children. The urban setting in downtown El Paso is historically known to be contaminated through various sources of contamination of heavy metals. The goal of this study was to compare whether children in a historically contaminated urban downtown area had significantly increased levels of lead exposure as compared to children in a demographically similar rural area approximately 20 miles north of the urban center, while controlling for gender and age. Cadmium and mercury were also measured for comparison purposes. It …


Development Of Method For Detection Of Lead In Samples Collected From Keweenaw Peninsula Mines, Michigan In Collaboration With Environmental Biology Research Students, Sindhu Reddy Aaireddy Apr 2013

Development Of Method For Detection Of Lead In Samples Collected From Keweenaw Peninsula Mines, Michigan In Collaboration With Environmental Biology Research Students, Sindhu Reddy Aaireddy

All Capstone Projects

Mining is one of the most important industries and a main cause of global pollution due to release of heavy metals into air, water, and soil. Some of these elements are persistent in the environment for years and bioaccumulation in living organisms causing toxic effects. Such elements are known as PBTs (persistent, bioaccumulate and toxic). The nature of toxicity depends on the properties, size of population exposed to it and period of exposure. For this reason, we are interested in developing a method to detect heavy metals in soil samples, mine tailings, plant and animal samples collected from surroundings of …


My Experience Exploring The Effects Of Lead (Pb +2) Toxicity In Drosophila Melanogaster Using Sociability Interaction Testing And Microarrays At The University Of Puerto Rico-Rio Piedras In San Juan, Puerto Rico, Charlton Diaz Jan 2013

My Experience Exploring The Effects Of Lead (Pb +2) Toxicity In Drosophila Melanogaster Using Sociability Interaction Testing And Microarrays At The University Of Puerto Rico-Rio Piedras In San Juan, Puerto Rico, Charlton Diaz

Honors Theses

Lead is an environmental contaminant widely dispersed throughout the world. Exposure to lead causes neurological damage in humans and may be linked to neurodevelopmental pathologies such as attention deficit hyperactivity disorder, antisocial behavior, and autistic spectrum disorders (ASD). Drosophila melanogaster (fruit flies) have been used to understand the behavioral, synaptic, and molecular changes that occur after developmental exposure to lead and to study ASD-associated pathology. Flies were exposed through the mother and until eclosion to either a lead-laced medium or a control corn-based medium and were isolated until the beginning for the behavioral studies. Sociability testing was done using a …


Lead And Associated Heavy Metal Distribution In El Paso, Texas, Ali Ragab Elkekli Jan 2013

Lead And Associated Heavy Metal Distribution In El Paso, Texas, Ali Ragab Elkekli

Open Access Theses & Dissertations

Contamination by lead and other heavy metals is one of the most important environmental concerns of today, locally and globally. This issue has led scientists and researchers to study the effect of heavy metals and their distribution in the environment. The aim of the present research is to document the concentration and geographic distribution of heavy metals in El Paso.

The selected heavy metals in the El Paso soil are lead, cadmium, chromium, zinc, antimony and copper. The soil sample for the study was collected during a previous community lead study (RO1 ESO11367; 2001-2006). 500 superficial soils samples were collected …


Lead And Cadmium In Seabirds Of South Africa, Carly Summers Aug 2012

Lead And Cadmium In Seabirds Of South Africa, Carly Summers

All Theses

Levels of lead (Pb) and cadmium (Cd) were investigated as potential stressors in adult African penguins (Spheniscus demersus) in the Western Cape Province, South Africa and in nine species of breeding seabirds on Marion Island, South Africa. Seabirds are sentinels of environmental pollution and allow researchers to study contaminant dynamics in marine ecosystems. Many seabirds occupy high trophic positions, which gives them the potential to highlight threats to other apex predators from environmental pollutants. They also accumulate contaminants in higher concentrations because of their greater size and lifespan than may be detectable in lower trophic organisms. Blood samples were collected …


Geomorphological Approach To Toxic Trace Metal Distribution Across A Medial Bar Deposit In The Trout Brook Of The Park River Watershed, Hartford, Ct, Kelsey Semrod Apr 2012

Geomorphological Approach To Toxic Trace Metal Distribution Across A Medial Bar Deposit In The Trout Brook Of The Park River Watershed, Hartford, Ct, Kelsey Semrod

Senior Theses and Projects

The Trout Brook, a major tributary of the Park River watershed, was sampled for heavy metals in sediment with a focus on Pb, Cu, Cd, and Zn. These metals are known to be contaminating the river due to a history of discharge from metal finishing industries. In a watershed-wide survey conducted in September 2011, high concentrations of metals were found in the Trout Brook, with some sites exceeding the probable effect concentration (PEC). The Trout Brook contains a Sanitary Sewer Overflow (SSO) and a vegetated medial bar that may be trapping sediment. Based on the results of the earlier studies, …


Low Level Exposure To Air Pollution And Risk Of Adverse Birth Outcomes In Hillsborough County, Florida, Maria B. Mainolfi Mar 2012

Low Level Exposure To Air Pollution And Risk Of Adverse Birth Outcomes In Hillsborough County, Florida, Maria B. Mainolfi

USF Tampa Graduate Theses and Dissertations

In this retrospective cohort from 2002 through 2007, 104,003 singleton live births in Hillsborough County, Florida were analyzed to elucidate the relationship between feto-infant morbidity outcomes and prenatal exposure to six criteria air pollutants. This study is based on three linked databases: The Florida Hospital Discharge database; The vital statistics records of singleton live births; Air Pollution meteorological data from the Environmental Protection Agency. There are six common air pollutants, particulate matter 2.5 (PM2.5), particulate matter 10 (PM10), ground-level ozone (O3), carbon monoxide (CO), nitrogen (NOx), and lead (Pb). These pollutants are harmful to human health and the environment. The …


Characterizing Dissolved Organic Matter And Cu2+, Zn2+, Ni2+, And Pb2+ Binding In Salt Water And Implications For Toxicity, Rachael L. Diamond Jan 2012

Characterizing Dissolved Organic Matter And Cu2+, Zn2+, Ni2+, And Pb2+ Binding In Salt Water And Implications For Toxicity, Rachael L. Diamond

Theses and Dissertations (Comprehensive)

The binding of metal to dissolved organic matter in aquatic environments is important in controlling the bioavailability and potential toxicity of metals such as Zn2+, Pb2+, Ni2+ and Cu2+. The purpose of this research is to: (i) quantify binding capacity to different sources of marine organic matter at environmentally relevant concentrations; (ii) test fluorescence quenching and voltammetric method for use in seawater conditions and; (iii) compare predicted speciation parameters with toxicological observations in the same samples.

Information regarding the solubility of copper and copper compounds is important for risk assessment and can be …


Defining A Molecular Mechanism For Lead Toxicity Via Calcium-Binding Proteins, Michael Kirberger May 2011

Defining A Molecular Mechanism For Lead Toxicity Via Calcium-Binding Proteins, Michael Kirberger

Chemistry Dissertations

Essential metals like Ca2+ and Zn2+ play critical roles in biological processes through protein interactions. Conversely, non-essential metals (e.g., Gd3+ and Pb2+) also interact with proteins, often with toxic effects. Molecular metal toxicity is assumed to be due to ionic displacement, and studies have demonstrated that Pb2+ replaces Zn2+, Ca2+ and other essential metals in proteins. The focus of this work was to compare protein Ca2+ and Pb2+ -binding sites and to investigate a mechanism of Pb2+ toxicity in Ca2+-binding proteins, particularly the intracellular trigger protein …


Analysis Of Mercury And Lead In Birds Of Prey From Gold-Mining Areas Of The Peruvian Amazon, Peggy Shrum Dec 2009

Analysis Of Mercury And Lead In Birds Of Prey From Gold-Mining Areas Of The Peruvian Amazon, Peggy Shrum

All Theses

This study was conducted to determine levels of lead and mercury in the raptors of the South-eastern Peruvian Amazon. The study took place within the Los Amigos Conservation Concession in Madre de Dios, Peru. Eighty-six raptors from among sixteen species were captured with Bal-Chatri traps. From each individual, feather samples were obtained for mercury analysis and blood was taken for lead analysis. Each raptor was then released without incident or injury.
Mercury amalgamation for gold extraction is widely used by small-scale, transient mining operations, which are numerous along the rivers and creeks in the tropical forests and other locations in …


Survey Of Health Effects Among Residents Adjacent To A National Priority List Site In Ssouthwest Virginia., Danette Haywood Dec 2003

Survey Of Health Effects Among Residents Adjacent To A National Priority List Site In Ssouthwest Virginia., Danette Haywood

Electronic Theses and Dissertations

The Saltville Waste Disposal Site is a National Priority List site used during the 77- year operation (1895–1972) of an electrolytic chlorine and caustic soda plant. A cross-sectional study was conducted to determine disease prevalence among Saltville Medical Center (SMC) patients. Diseases associated with chronic exposures to mercury, arsenic, and lead were reviewed in patient records and these data were analyzed. Ratios of illness observed at the SMC were compared to health studies of similar environmental exposures and disease prevalence among residents of neighboring communities. Prevalence ratios were calculated for residents and non-residents of Saltville who were SMC patients. Saltville …


Analyzing The Education Mandate Of Title X: The Lead-Based Paint Reduction Act Of 1992, William Troy Roussel Jan 2002

Analyzing The Education Mandate Of Title X: The Lead-Based Paint Reduction Act Of 1992, William Troy Roussel

LSU Master's Theses

The Environmental Protection Agency appropriates 400 million dollars in grant funding under the authority of Title X: Residential Lead-based Paint Hazard Reduction Act of 1992. The education mandate of Title X states that the federal government must build an infrastructure to educate the public, real estate professionals, and contractors, to name a few, on the hazards of lead-based paint. A survey was developed to assess the effectiveness of the Title X education mandate. Contractors in the City of New Orleans were surveyed to assess their knowledge of the act and the hazards of lead-based paint before attending an 8-hour training …


Characterization And Implementation Of A Continuos Flow Trace Metal Preconcentration System For Inductively Couples Plasma Atomic Emission Spectrometry, Robert N. Sibley Jan 1992

Characterization And Implementation Of A Continuos Flow Trace Metal Preconcentration System For Inductively Couples Plasma Atomic Emission Spectrometry, Robert N. Sibley

Senior Scholar Papers

A continuous flow pre-concentration system for analysis of trace metals in natural waters was characterized and used to determine the copper(II) and lead(II) concentrations in seawater from Penobscot Bay, Maine. Pre-concentrated samples were analyzed by inductively coupled plasma atomic emission spectrometry (ICP-AES). System characterization involved elucidation of the thermodynamic complexation constants, KCu(II) and KPb(II), for Cu(II) and Pb(II) with the pre-concentration column chromatographic material. This was done in aqueous media of known pH and ionic strength. The column contained 8-hydroxyquinoline immobilized on Toyopearl HW-75 fractogel chromatographic resin. The buffer system used for metal binding experiments was an equimolar mixture of …


Effect Of Temperature On The Association Constants Of Some Divalent Metal Ions With Chloride In Sea Water-Like Solutions, Jose Vinicio Macias Zamora Jan 1984

Effect Of Temperature On The Association Constants Of Some Divalent Metal Ions With Chloride In Sea Water-Like Solutions, Jose Vinicio Macias Zamora

University of the Pacific Theses and Dissertations

Association constants for the formation of lead (II) chloride complexes were studies in aqueous solutions also containing copper (II) and cadmium (II) ions.

The ionic strength was adjusted with sodium perchlorate to resemble that of sea water. The temperature was set at fixed values between 5° and 35° C to determine the effect on the equilibria in these systems. The total metal concentration was less than 10-8 M.

Differential pulse anodic striping voltammetry was used with a conventional three electrode system and a thin-film working electrode of Pt/Hg. Complex formation was followed as a function of the ligand concentration …


Potentiometric Titration Of Sulfate Using A Lead-Mercury Amalgam Indicator Electrode, Charles W. Robbins May 1972

Potentiometric Titration Of Sulfate Using A Lead-Mercury Amalgam Indicator Electrode, Charles W. Robbins

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A lead sensitive indicator electrode was constructed with a 70 percent lead and 30 percent mercury amalgam billet. Sulfate concentrations in pure solutions, natural waters, and soil saturation extracts were determined potentiometrically using the lead-mercury amalgam indicator electrode and a standard calomel reference electrode. Sulfate concentrations over the range 0.4 to 20 milliequivalents sulfate per liter were determined with an automatic titrator and compared to a turbidimetric method for accuracy and precision. The values obtained by the two methods from twelve saturation extracts and three subsurface drainage waters were not significantly different and the potentiometric method was generally more precise. …


A Study Of The Effects Of The Chloride Ion On The Lead-Silver Anodes And On The Lead Tenor Of The Zinc Deposit In Zinc Electrolysis, William A. Mitchell May 1953

A Study Of The Effects Of The Chloride Ion On The Lead-Silver Anodes And On The Lead Tenor Of The Zinc Deposit In Zinc Electrolysis, William A. Mitchell

Bachelors Theses and Reports, 1928 - 1970

The electrolyte used in the commercial production of electrolytic zinc from zinc sulphate solutions contains small amounts of impurities each of which has its own effects upon the process. Impurities such as antimony, cobalt, nickel, and iron tend to lower the current efficiency while other impurities such as chlorine, fluorine, and nitrates tend to increase the corrosion of the lead anodes and thereby increase the lead tenor of the zinc deposit.


Benefication Of An Oxidized Lead Ore From The Franklin Mine Lewis And Clark County, Jack D. Mclenegan May 1949

Benefication Of An Oxidized Lead Ore From The Franklin Mine Lewis And Clark County, Jack D. Mclenegan

Bachelors Theses and Reports, 1928 - 1970

This thesis is concerned with the beneficiation of an oxidized lead ore. Emphasis was placed upon concentration by flotation rather than by gravity methods, although some investigation was made with the Wilfley shaking table. The concentration of lead minerals received most consideration in the problem, but wherever possible attempts were made to increase the silver and gold concentration along with the lead.


The Electroformation Of Lithium-Lead Alloys From Molten Electrolytes, Thomas Prater May 1941

The Electroformation Of Lithium-Lead Alloys From Molten Electrolytes, Thomas Prater

Bachelors Theses and Reports, 1928 - 1970

An attempt was made to make lead-lithium alloys by electrodeposition of lithium using a molten bath and a molten lead cathode.The variables taken into consideration were: composition of the melt, temperature of the melt, and current density. The purpose of changing these factors was to determine what effect each had on the current efficiency.


Structure Of Eutectics, Dilip K. Das May 1939

Structure Of Eutectics, Dilip K. Das

Bachelors Theses and Reports, 1928 - 1970

The present paper is a result of work done on the study of structures of eutectics of a certain eutectic-forming binary systems. In this research work no systems with intermetallic compounds have been studied.


A Study Of Solders, John D. Prater May 1939

A Study Of Solders, John D. Prater

Bachelors Theses and Reports, 1928 - 1970

The purpose of this paper is to furnish a qualitative method of comparing the degree of wetting of various solders upon different plate metals when several fluxes are used.


Electrolytic Recovery Of Copper And Zinc From Brass., V. Kent Loughran May 1938

Electrolytic Recovery Of Copper And Zinc From Brass., V. Kent Loughran

Bachelors Theses and Reports, 1928 - 1970

The reclamation of metals from scrap is becoming increasingly important in the metallurgical industry. Copper, because it does not corrode readily and is electronegative to most common metals, is peculiarly adapted to reclamation.


The Effects Of Lime On The Amalgamation Of Gold., Rollien R. Wells May 1936

The Effects Of Lime On The Amalgamation Of Gold., Rollien R. Wells

Bachelors Theses and Reports, 1928 - 1970

An amalgam is an alloy of mercury with other metals, and amalgamation is the art of making or forming amalgams. In metallurgical language the word is limited to the means adopted for the recovery of gold and silver from their ores by the use of mercury.