Environmental Chemistry Commons^™

Development Of Quantitative Methods To Study Pfas Using Proton Induced Gamma-Ray Emission, Colin Langton

Honors Theses

Per- and polyfluoroalkyl substances (PFAS) are man-made chemicals that have become a major environmental concern. They can be found in a broad range of everyday products and pose a significant risk to the public due to their adverse health effects. They are persistent, bioaccumulate and do not break down in the environment. This project specifically aims to determine the concentration of Fluorine, a key identifier of PFAS, in environmental samples. To do this, we employ proton induced gamma-ray emission (PIGE) to screen for Fluorine within our samples. PIGE is performed at the Union College Ion Beam Analysis Laboratory using a …

The Design Of A Pcr-Based Assay To Detect And Isolate The Serine Palmitolytransferase Gene From Environmental Bacteria, Lana Taylor

Honors Theses

Sphingolipids are a natural class of lipids that function as structural elements of cell membranes and signaling molecules for important cellular activities such as cell growth, differentiation, apoptosis, recognition, and adhesion. These lipids can be found universally in eukaryotic cells as well as some species of bacteria, such as those found in the human gut microbiome and in the environment in soils. Though sphingolipid production is rare in bacteria, both eukaryotic and prokaryotic sphingolipid biosynthesis begin with the condensation of serine and palmitoyl CoA into 3-ketodihydrosphingosine catalyzed by the enzyme serine palmitoyltransferase (SPT). In recent years, several studies have shown …

Isolated Point Discharges Into Coastal Swashes As Nutrient Sources To Coastal Waters, Mary E. Olsen

Honors Theses

Coastal water quality in the Grand Strand of South Carolina is directly influenced by human activities. Nutrient-rich runoff, stemming from numerous anthropogenic sources, finds its way into coastal waters through freshwater inputs often through tidal creeks, termed swashes. In order to better describe the amount of nutrient inputs into Singleton Swash and White Point Swash, we examine anthropogenic runoff from isolated identifiable point discharges and their nutrient concentrations. We report concentrations of dissolved inorganic nitrogen (DIN, as the sum of nitrate, nitrite and ammonium) and phosphate in discharge and creek water. We hypothesize that nutrient concentrations of isolated, minor point …

The Quantitative Assessment Of Pond Scum: An Examination Of The Biogeochemistry Of Phosphorus Cycling In The Belgrade Lakes, Abbey M. Sykes

Honors Theses

The internal recycling phosphorus in freshwater lake bottom sediments represents a significant source of hypolimnetic phosphorus (P) release for many of Maine’s lakes. In summer months, Maine lakes often thermally stratify and the lake hypolimnion develops anoxia, leading to a reduction in redox potential at the sediment-water interface. These reducing conditions facilitate the reductive dissolution of ferric iron, and, since phosphorus is often present in freshwater lake sediments as solid FeOOH-PO₄ complexes, results in release of soluble phosphorus into the water column. Our current study presents field and laboratory data from sediment fractionation extractions designed to quantify concentrations of …

Development Of Catalytic Chromia-Based Aerogels, Fiona Fitzgerald

Honors Theses

Over one billion automobiles are in use around the world, the majority of which employ internal combustion engines. Catalytic converters are used to convert the toxic compounds found in car exhaust -- carbon monoxide, nitrogen oxides (NOx) and hydrocarbons -- to less harmful gases. The typical catalytic converter employs as catalysts expensive raw materials (platinum, palladium and/or rhodium) wash-coated onto an alumina-based ceramic substrate. Aerogel materials have high surface area and thermal stability, properties that make them attractive for catalysis applications. Aerogels made with transition metal oxides are candidates to replace platinum in the catalytic converter. Chromium oxide (chromia) materials …

Spectroscopic And Computational Studies Of The Agricultural Active Ingredient Dicamba, James Johnson

Honors Theses

3,6-dichloro-2-methoxy benzoic acid, more commonly known as Dicamba, is the active ingredient in an array of pesticides used on farmlands across the globe. Dicamba’s mode of action works by mimicking the plant hormone auxin, which is synonymous to growth hormones in mammals. The mimicking of auxin results in excessive elongation and growing, which is eventually fatal for plants when the rate of growth can no longer be sustained. Dicamba has risen in prominence in recent years due to drift damage as a result of Dicamba’s high volatility. Having the ability to identify Dicamba is crucial for the agricultural industry. The …

The Effects Of Climate Change And Forest Disturbances On Terpene Production Of White Pine (Pinus Strobus) And Red Pine (Pinus Resinosa) In Northern Michigan, Troy Dehagen

Honors Theses

The secondary impacts that climate change may have on the interactions between forests and the atmosphere through forest disturbances is of increasing interest as the climate continues to change. Anthropogenic climate change, which is a direct result of coal and fossil fuel emissions, is likely to impact forest ecology through increased temperatures and extreme precipitation events, thus increasing the frequency and severity of climate-induced forest disturbances. Forest disturbances may have a secondary impact on the production and emission of biogenic volatile organic compounds (BVOC) within forests. In the presence of oxides of nitrogen (NO_x) produced from fossil fuel …

Detecting Cyanobacteria Toxins: The Human Health Impact Of An Environmental Problem, Lillian E. Naimie

Honors Theses

Cyanobacteria blooms are a growing concern in the world, as they can form a dense and sometimes toxin scum on water bodies. This paper will outline and discuss the environmental conditions that produce cyanobacteria bloom with a focus on the toxins produced by blooms and specifically the detection of these toxins through two analytical methods. Of the various toxins cyanobacteria are capable of producing, this paper will focus on microcystins and BMAA, a family of hepatotoxins and a specific neurotoxin respectively. The two analytical methods discussed are liquid chromatography coupled mass spectrometry and ELISA kit techniques. The advantages and drawbacks …

Synthesis And Characterization Of Organically Modified Hectorites For Sequestration Of Pfaas From Contaminated Drinking Water, Alexandra Pagano

Honors Theses

Perfluoroalkyl Acids (PFAAs), a family of industrial chemicals, are found in household products such as pizza boxes, microwave popcorn bags, and non-stick pans. PFAAs of different carbon chain lengths and ionic head groups exist, such as PFOA (perfluorooctanoic acid) and PFOS (perfluorooctane sulfonic acid). Used without regulation in industry for decades, PFAAs only recently became recognized as contaminants of emerging concern, since they are bioaccumulative in organisms, persistent in the environment, and toxic. PFAAs are known to accumulate in the blood, liver and kidneys, and drinking water contaminated with PFAAs has been linked to certain types of cancer. Therefore, it …

Presence And Potential Sources Of Pharmaceutical And Personal Care Product Chemicals In Messalonskee Lake, Alyssa T. Kullberg

Honors Theses

Pharmaceuticals and personal care product chemicals (PPCPs) represent a large group of contaminants that are mostly not regulated in surface or drinking water and whose presence and environmental and health impacts are poorly understood. We investigated the presence and potential sources of 18 PPCPs in Messalonskee Lake. We collected samples four times over the summer of 2017 at 13 sites around the lake. Samples were tested for PPCPs using liquid chromatography-tandem mass spectrometry. We detected five out of the 18 PPCPs we tested for at the ng/L level: caffeine, 1,7-dimethylxanthine, acetaminophen, sulfachloropyridazine, and amphetamine. PPCPs showed a significant positive correlation …

Stable Bromine Isotope Signature Of Bromoform From Enzymatic And Abiotic Formation Pathways And Its Application In Identifying Sources Of Environmental Bromoform In The Damariscotta River, Chengyang Wang

Honors Theses

Bromoform is a major source of atmospheric bromine. Most bromoform is produced by marine organisms including macroalgae and phytoplankton, using the enzyme bromoperoxidase (BPO). Bromoform can also be a byproduct of industrial processes such as water disinfection. Identifying sources of environmental bromoform is still a challenge. A novel technique of using quadrupole mass spectrometry coupled to a gas chromatography (GCqMS) was developed and optimized for Br isotope analyses. The study shows that GCqMS in single ion monitoring (SIM) mode can measure 81Br with precision of around ±0.7‰ (60pmol bromoform injected). This study aims to investigate stable Br isotopes of bromoform …

The Clean Air Act And Its Impact On Ground Level Ozone Pollution Levels In Los Angeles, California, Rebecca G. Ford

Honors Theses

Ozone (O₃) occurs naturally as a protective, ultraviolet radiation-shielding “Ozone Layer” in the Stratosphere and as a photochemically produced pollutant in the Troposphere. The Clean Air Act (CAA) of 1970 regulates the emission and concentration of O₃ and five other atmospheric pollutants. Since the signing of the CAA, the ongoing question has been whether or not the National Ambient Air Quality Standards (NAAQS) and regulatory policies have had an effect on decreasing O₃ concentration. The Los Angeles metropolitan area is a prime example of how O₃ can be a public health hazard, and taint a …

Pine Needle Pyrolysis: Bio-Waste Into Biofuel, Alexandra Fuentes

Honors Theses

This project explores the alternate uses of biomass. In particular it focuses on pine needles as a source for biofuels. Pine needles are of interest because in certain Mountain communities they are collected and removed from residential properties. By removing the pine needles, communities create a “defensible space” to prevent wild fires from destroying homes and property. These needles are often placed in regional landfills. The South Tahoe Refuse and Recycling Services alone has more than 4,340 tons of pine needles dumped at their facility annually. This large amount of biomass can be a potential energy source.

The focus of …

A Novel Method For Determination Of Ammonium Isotope Ratios With Electrospray Ionization Mass Spectrometry, Rebecca J. Chmiel

Honors Theses

Nitrogen (¹⁵N) isotope tracer studies are an invaluable tool for understanding the rate of N transformations in the environment. A mechanistic understanding of N cycling is critical to management of excess N availability in freshwater and marine ecosystems. Conventional methods for measuring ¹⁵N:¹⁴N of dissolved inorganic nitrogen species are time consuming and require large sample volumes. Here, we present a technique for measuring ¹⁵N:¹⁴N in ammonium (NH₄⁺) using electrospray ionization mass spectrometry (ESI-MS). NH₄⁺ present in small volumes of sample (3 ml) is complexed with phenol via …

Effects Of Cigarette Butts On Coastal Waters: An Elemental Analysis Of Seawater From St. Simon’S Island, Katherine Adorati

Honors Theses

Cigarette litter can have detrimental effects on the environment, specifically when taking into account that over 4.5 trillion cigarette butts are littered every year. Within seawater, trace elements present in cigarettes may leach into the ocean, having damaging effects on the marine ecosystem. The goal of this research was to investigate if elemental contaminants leached from cigarette litter are significant in samples of seawater collected near St. Simon’s Island at both high and low tides, surrounding a beach party during the Florida/Georgia football game which occurred on November 1, 2014. Samples were collected in the months prior to and during …

Influence Of The Sea Surface Microlayer On Ozone Deposition Velocity, Kathryn Moore

Honors Theses

The biogeochemical cycles of both iodine and ozone are strongly linked to human health and global climate and are tightly coupled through chemical processes occurring in the surface ocean and troposphere. The concentration and distribution of these compounds have the potential to drive the oxidizing capacity and suite of chemical reactions occurring in the marine boundary layer. However, modeling coupled ocean-atmosphere systems involving them is challenging because of a limited understanding of the magnitude and dominant mechanisms controlling the fluxes of both species, in addition to temporally and spatially heterogeneous distributions of ozone and iodine in the sea surface and …

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 …

A Study Of Dislocations In Crystals Using The Technique Of Chemical Etching, Ramona R. Dennis

Honors Theses

The beauty of many of the crystalline solids has attracted man's attention from the earliest times. Eventually the science of crystallography developed from studies of their shapes. The word crystal sterns from the Greek word "krystallos" meaning "clear ice." The word was first applied to describe the clear quartz crystals found in the Swiss Alps. The crystals were thought to be formed from water under conditions of extreme cold.

The earliest recorded crystallographic observation was in 1597 by Andreas Libarius. He noticed that crystals of different substances often have characteristic shapes. He suggested that the salts in mineral water could …

A Study On Gaseous Ebullitions Of De Gray Reservoir, Arkansas, David Pinkston

Honors Theses

This study was undertaken in order to determine the nature of and the factors that influence the gaseous ebullitions of De Gray Reservoir near Arkadelphia, Arkansas during a yearly cycle.

Two major types of gaseous ebullition are described in the literature. The first has to do with the production and ebullition of elemental oxygen from photosynthesis (Porcella et al., 1975). Hutchinson (1957) predicts that the formation of oxygen bubbles in this manner is limited to very shallow, well lighted, warm waters.

The second type of gaseous ebullition involves the anaerobic digestion of organic matter (Reeburgh, 1969). Anaerobic conditions exist in …

Determination Of The Rate Of Formation Of Hcn, Mitchell Hull

Honors Theses

Nitric oxide is a major air pollutant arising from fossil fuel combustion, yet the fuel contribution to its formulation is uncertain. Since, in combustion, fossil fuels undergo disintegration before oxidation takes place, the study of the pyrolsis of a model constituent of fossil fuels can shed light on NO formation. The rate of inert pyrolytic disappearance of pyridine and the rate of formation of the principal Nitrogen-containing pyrolytic product, HCN, was studied in an inert atmosphere. The rate constant for the formation of HCN and its temperature dependence were determined.

Solubility Of Manganese And Iron In Impoundment Waters, Jim Gilbert

Honors Theses

The purpose of this paper is to show the rate of solubility of certain elements (manganese and iron) in impoundment waters. The rate at which manganese and iron becomes soluble is important in determining if there is a change in the solubility of these elements in impoundment water and free running water.

The solubility of an element under impoundment waters represents a cycle. The mud on the bottom of impoundment waters contain the elements that are insoluble. At a certain stage the element becomes soluble, and it is released from the mud. The soluble element is much lighter than the …

An Attempt To Determine Molybdenum By Atomic Absorption Spectrophotometry, Gary Rice

Honors Theses

An attempt was made to work out a method for routinely determining molybdenum by atomic absorption spectrophotometry. A stock standard was prepared containing 100 ppm molybdenum as MO4. Sensitivity of the spectrophotometer was found to be zero for aqueous solutions in the 1-10 ppm range. A pH-dependence study of extraction of the molybdate with DDC and MIBK gave best results at about pH 4.

Calcium Carbonate Determinations, James Phelan

Honors Theses

Calcium compounds are abundant in nature. The carbonate ion may exist in many varieties, such as aragonite and limestone. Of major importance in the following discussion, however, is calcite. Calcium carbonate may well be of animal origin, prime examples being sea shells, coral, and chalk. Dolomite, on the other hand, is a double carbonate of calcium and magnesium. Calcium in natural waters exists mainly as a bicarbonate, Ca(HCO3)2, which is temporary hardness, or as a sulfate, which is permanent hardness.

From determinations made periodically (every two weeks) since August 1966, a decrease has been found in the calcium content as …