Fluoride intake is essential for dental health, yet excessive consumption can lead to fluorosis, a condition negatively affecting teeth and bones. Tea, one of the most widely consumed beverages globally, naturally accumulates fluoride, making it a significant but often overlooked dietary source. Black tea is the most popular type of tea consumed in the U.S. In this study we compared fluoride levels across six brands of black tea and investigated how brewing conditions and water sources affect fluoride concentrations in tea. We brewed black tea from six locally popular brands (Lipton, Tazo, Fortnum & Mason, Twinings, Tetly, and Harney & Sons), using two water sources (distilled water and Seattle tap water), with four samples for each brand using both water sources. We brewed 50 mL of water at 100°C, then we let each sample of the tea sit for 5, 10, and 20 minutes. Ion chromatography was used to measure fluoride concentrations at each time interval. We compared these values to the U.S. Environmental Protection Agency's (EPA) recommended fluoride level of 4.0 mg/L. Our results help characterize the variation between brands and the influence of brewing duration on fluoride release. These findings contribute to a better understanding of fluoride exposure from tea consumption, helping consumers make informed choices about their dietary fluoride intake.

Beaver dams can function as natural filters helping decrease pollution in streams, creeks, and rivers. Beaver dams slow down the water flow in a creek or river, forming ponds that help trap excessive nutrients. An excess of nutrients such as phosphate and nitrate can cause eutrophication, leading to increased algal blooms that can produce toxins and ultimately deplete oxygen in the water. This study investigates the ion levels of chloride, fluoride, phosphate, nitrate, sulfate, and bromide upstream and downstream of the major beaver dam at Pipers Creek in North Seattle's Carkeek Park over the course of a year to better understand the long-term impacts of the dam. We collected three water samples at each of eleven sites along the creek, eight upstream from the dam, and three downstream. Ion chromatography was used to measure the concentrations of anions at each site. The results of this study help elucidate the role of beavers in moderating water quality and provide important baseline data documenting seasonal variations in the nutrient load at Pipers Creek. These findings can also be used to better understand the impact of new beaver dams in other freshwater systems.

The health risks of particulate matter measuring less than 2.5 micrometers (PM2.5)  include: respiratory disease, cardiovascular issues, and cognitive impairments. Its presence near schools and colleges remains underexplored. This study examines the relationship between PM2.5 exposure levels and academic outcomes in community colleges located in historically redlined neighborhoods across four major West Coast cities: Los Angeles and San Diego in California; Portland, Oregon; and the greater Seattle area in Washington. Using data from the PurpleAir Network, state air quality indices, and community college governing bodies, we analyzed and compared PM2.5 levels near institutions located within historically redlined neighborhoods and institutions located outside those neighborhoods. Leveraging the Python programming language and Google Colab, we examined correlations between an institution’s demographic makeup and transfer rates relative to PM2.5 exposure. Data sets obtained were filtered between the hours of 8 AM and 1 PM during the months of January 2024 through December 2024. Our findings indicate a correlation between higher PM2.5 exposure and lower academic performance for colleges serving predominantly racially marginalized communities located within historically redlined neighborhoods. This research reinforces the role of environmental inequities in shaping educational disparities and highlights the need for targeted policies to address air quality in affected communities.

Low-income communities are often disproportionately exposed to air pollution. High concentrations of pollutants such as particulate matter under 2.5 µm (PM2.5) and human aerosol emissions, including carbon dioxide (CO2), have been linked to various health and cognitive issues. Performance arts, including singing and playing instruments, produce human aerosol emissions and are considered high risk for airborne disease transmission. Our study evaluated the accumulation of CO2 and PM2.5 in high-risk environments (band classrooms) in low-income public schools in King County (WA), to determine whether there is a correlation between accumulation rates and Title 1 designation. Title 1 designation, which provides government funding for schools with a high percentage of students from low-income households, was used to represent low-income communities. We compared four middle schools that qualified for Title 1 designation to one school that did not qualify. Concentrations of CO2 and PM2.5 were measured using the Aranet4 Home CO2 sensor and a PurpleAir Classic sensor for PM2.5. We took a baseline measurement of both concentrations when the classroom was unoccupied. We then analyzed the change in concentration rates when classes were in session, taking into account classroom size and number of students. Our data showed concentrations above recommended levels at 1,370 ppm (parts per million) for CO2 in one of the Title 1 schools suggesting that Title 1 schools may be at greater risk of poor indoor air quality, though additional studies are needed. This additional exposure to pollutants and human aerosol emissions in already high-risk environments like band classrooms may lead to increased airborne disease transmission, highlighting the disparity in healthy learning environments. These classrooms require additional measures to maintain healthy concentrations of CO2 and PM2.5 to reduce the risk of airborne disease transmission particularly in low-income communities. 

The balance of ions in soil and water directly impacts sustainable agriculture, human health, and livestock well-being. Small family farms, such as the one in this study, often depend on well water for household and agricultural use, making water quality essential for both food safety and long-term farm viability. This study investigates the spatial distribution of key anions, including nitrate (NO₃⁻), nitrite (NO₂⁻), and phosphate (PO₄³⁻), in soil and well water across a small family-operated farm in Woodinville, WA. These ions were selected due to their roles in plant growth, soil chemistry, and potential health effects on humans and animals. The farm sustains 68 animals, including chickens, cows, donkeys, alpacas, llamas, sheep, quails, and horses, and provides food and water for seven residents. Soil and water samples were collected from distinct zones, including livestock pens, vegetable fields, and tap water from the farm’s well, to evaluate how land use influences ion distribution. Soil samples were collected at multiple sites; ions were extracted from the samples using a  common water extraction method. Ion chromatography (IC) was employed to quantify anion concentrations and assess spatial variability. While this study does not determine definitive sources of the ions, analyzing variations in these ion concentrations near crop fields and livestock areas can help assess potential nutrient leaching and runoff. This type of comparative analysis of soil and well water samples helps quantify potential risks to both farm operations and the health of residents and livestock. This research underscores the importance of ongoing water and soil quality monitoring to ensure the sustainability of small-scale farms that rely on well water and homegrown food, while offering insights for improved land and resource management practices

Glaciers have long been used as the bellwethers of climate change, given their ability to store gases, dust, microbes, and other environmental materials in their layers; tracking their recession has also been an important visual indicator of climate change. In this research, I examine how anions in newly exposed vary with depth. To do this, I took samples from exposed vertical ice faces on the Coleman glacier, on the north face of Mount Baker. Samples were thawed and analyzed using ion chromatography.  Trace amounts of chloride, nitrate, sulfate, and phosphate were found in each sample. The ion concentrations showed no trend with depth, and the ice itself appeared uniform. This is in contrast from vertical cores taken from solid ice in numerous other surveys, which show distinct annual layers and variation. This suggests that the ice at vertical faces has different properties from that at the top layers, including in its ability to trap environmental markers. Further research is needed to confirm this difference and examine which of these markers is most affected. Increased understanding of these markers could give more insight into how glaciers change over time and interact with their environment.

Safe drinking water in schools is crucial for children's safety and academic performance. While Seattle Public Schools has tested for some contaminants, such as lead, the district's responsibility for ion-specific testing for anions such as phosphate, bromide, nitrite, nitrate, chloride, sulfate, and sulfite is less clear. High concentrations of anions pose potential health risks, including reduced oxygen in red blood cells, higher risks of tumors in children, and diarrhea. This research investigated the anion concentration in water fountains across seven high schools in the Seattle Public Schools. Twenty-one water samples were collected from seven public high schools and analyzed for anion concentration using ion chromatography. Results were compared to the Environmental Protection Agency's (EPA) maximum contaminant level (MCL). All test samples were below the EPA's MCL. These results suggest that the drinking water in these schools does not pose potential risks to students from anion contamination. While regular monitoring and management are still necessary to maintain safe drinking water, Seattle Public Schools have met the safety requirements for anion concentration in their drinking water. 

Non-fatal firearm injuries significantly outnumber fatal ones, yet research of acute rehabilitation for these injuries remains sparse leading to disproportionate effects on marginalized populations. The goal of this study was to characterize the use of inpatient rehabilitation (IPR) after firearm-related injury in local and nationwide samples. I hypothesized that patients who suffered from gunshot wounds (GSWs) and are transferred from acute hospitalization to IPR (referred to as the GSW IPR population) have greater injury severity compared to other traumatic injuries. Injury severity was assessed using three metrics: Injury Severity Score (ISS) total length of stay (LOS) at the hospital and Intensive Care Unit (ICU LOS). Additionally, we sought to evaluate associations between patient demographics—age, primary insurance type, race—and the frequency of discharge to IPR due to GSWs. Patients were identified locally from the Harborview Medical Center (HMC) Trauma Registry, and nationally, using the Trauma Quality Improvement Program (TQIP) database with deidentified patient records from over 700 participating Level I-V and undesignated trauma centers. R statistical analysis displayed both HMC and TQIP samples having a much higher ISS, LOS, and ICU LOS for GSW IPR patients compared to other traumatic injuries, supporting my primary hypothesis. Demographic data also revealed GSW IPR patients were more likely to be younger, and insured by Medicaid for both sampled. Interestingly, national data showed that patients with a GSW were less likely to discharge to IPR, and more likely to be Black or Hispanic, while local data concluded opposite findings, with GSW patients being more likely to discharge to IPR, and no significant racial association to IPR frequency. This study raised questions regarding the variability between regional and national health outcomes, and allowed us to assess demographic disparities and potential gaps in accessibility to rehabilitation services after fire-arm related injuries.

The collection of underwater sounds for anomaly detection can contain white noise, making it challenging to analyze data. This project’s goal was to improve the process of analyzing data and detection in the presence of white noise. The project focused on the detection of the fin whale’s twenty hertz down sweep call. The call is visually recognizable on the spectrogram, a tool that visualizes audio using shape and color over time as a static image. The project used detection output from the publicly available WhaleTracks software as a comparison to the method presented herein. I focused on tuning a part of the detection process to better detect fin whale calls in a noisy environment. We focused on studying changes in the Python script find_peaks function’s prominence parameter in a normalized signal. The prominence parameter is a variable responsible for characterizing the sensitivity of the detector. Lower values of the prominence parameter increase the sensitivity of the detector and higher numbers lower the sensitivity. My research analyzed how changes in the prominence parameter would affect the detection of fin whale calls. Using a Google Colab notebook, I modified a set of code that took in data, processed the data into a readable form for the machine, detected peaks in the twenty hertz range, and then printed the data in the form of several graphs readable for the human eye. Based on the time frames used for evaluation, we concluded that the best value for the prominence parameter for all environmental conditions was three. In the future, this prominence parameter should instead be made dynamic, changing depending on the amount of sound energy present in the audio data.

Halofun is an object-oriented program using Chebfun software in MATLAB that employs low rank spectral approximation methods to efficiently compute and store functions on annuli. The computational cost of numerical techniques are often a major constraint in computing and working with large and complex mathematical problems. Low rank representations of functions can reduce computational costs; low rank function approximation has relations and advantages similar to that of the singular value decomposition in terms of isolating the most important features of the problem. Similar to writing a matrix representation as a sum of rank 1 matrices, we can write a function as a sum of k rank 1 functions. By using a representation based on Chebyshev/Fourier basis functions, we can make use of fast, FFT-based transforms and other fast algorithms to compute with functions on annuli. Halofun expands on previously developed low rank spectral methods in rectangular, circular, disk and spherical domains, so that a user-friendly software for fast and spectrally accurate computations now exists for ring-shaped domains.

The efficiency and reliability of solar energy systems depend on panel orientation and energy storage performance, especially in seasonal climates. This research focuses on optimizing solar panel angles and addressing energy storage inefficiencies to enhance the University of Washington Tacoma's Giving Garden solar energy system. By adjusting panel tilt based on seasonal variations, the system can maximize solar energy capture throughout the year. Furthermore, diagnosing and resolving storage inefficiencies—such as battery faults, voltage fluctuations, and improper charging cycles—can improve overall system performance and longevity. This study also examines fault protection mechanisms within the system, identifying current leakage points and implementing solutions to maintain battery health. Through experimental analysis, real-time data collection, and practical system adjustments, this research aims to develop a comprehensive strategy for improving energy output, minimizing losses, and ensuring a more resilient off-grid power solution for sustainable agricultural applications.