Browsing by Subject "Pollution"
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Item Open Access An Analysis of Erosion and Sedimentation Programs in North Carolina(2010-04-30T15:03:13Z) Stogner, MichelleSedimentation is considered to be the number one pollutant of North Carolina waters. When excessive sediments enter the water, normally as a result of construction or agriculture, severe ecological consequences occur. Soil particles can transport chemical pollutants, increase turbidity and decrease the quality of receiving waters. In North Carolina there are 53 local (county or city) Erosion and Sedimentation Control (E&SC) Programs that have the authority to approve E&SC Plans for construction activities within their own jurisdictional boundaries. This Masters Project evaluated 24 E&SC programs by examining their Ordinances and comparing them with the model ordinance drafted by Department of Environment and Natural Resources. In addition, I organized and analyzed local program data that was collected from the 24 programs through a survey as part of the Muddy Waters Watch Program, an Environmental Protection Agency Section 319 grant project. The data extracted was on buffer widths, staff, active construction sites, notices of violations, limit of site exposure and graded slopes and fills. In order to assess the importance of these regulations, I conducted a riparian buffer analysis on the French Broad River using the National Land Cover Dataset Change Product for 1992 to 2001. The results indicate that the number of staff and their qualifications varied among the programs. On average, each active construction site was inspected once a week, and in some situations once every two weeks. The ordinance analysis showed that while each program has the model ordinance as a reference, each is unique to their area. However, certain aspects of the model ordinance, such as exposure and slopes, should be modified for different North Carolina regions. The French Broad River buffer analysis demonstrated the importance for adequate buffer regulations. While the amount of change was small, the change that did occur was classified as buffering land types (forest and grasslands) to pollutant land types (urban, industrial and agriculture). The French Broad River has the least stringent buffer regulations, the most active construction sites and the steepest slopes. Areas such as this are more prone to sediment pollution and thus should have wider buffer widths.Item Open Access Characterizing Environmental Per- and Polyfluoroalkyl Substance (PFAS) Exposure and Effects in North Carolina Communities(2022) Hall, Samantha MariePer- and polyfluoroalkyl substances (PFAS) are synthetic chemicals used in a wide array of products and applications (e.g., nonstick cookware, waterproof and water-repellent textiles, firefighting foam). Following their decades of use, PFAS have garnered concern as “forever chemicals” due to their extreme persistence in the environment and in humans. PFAS have further elicited concern because they have been linked to adverse health effects in humans, and their huge number (over 12,000 different chemicals) and complex chemistry make them very challenging to analyze and study for exposure and toxicology. Two particular PFAS chemicals, perfluorooctanoate (PFOA) and perfluorooctane sulfonate (PFOS), are drinking water contaminants that can be found in the blood of the vast majority of people. PFOA and PFOS are also linked to toxic effects like kidney and testicular cancer, increased blood cholesterol, and reproductive outcomes. These two chemicals are being phased out of use and federal drinking water standards are likely upcoming. However, the replacements for these two chemicals are much less well-characterized, and many of these newer, replacement PFAS chemicals can be found in the environment of North Carolina due (at least in part) to industrial pollution.
The overarching goal of this dissertation was to characterize the potential exposure and health effects of PFAS in North Carolina communities. The surface water and drinking water in some areas of North Carolina have been found to be contaminated with PFAS; however, there are additional routes of PFAS exposure beyond drinking water, such as ingestion of house dust or placental transfer during pregnancy. This dissertation explores various routes of PFAS exposure and better characterizes the specific PFAS analytes that can be found in North Carolina and the concentrations in which they are present. Additionally, this dissertation evaluates this exposure and potential associations with some adverse health outcomes in a few North Carolina communities.
In Chapter 2, the relationships between PFAS exposure during pregnancy and birth outcomes are explored. This chapter includes data on PFAS concentrations in placenta samples from 120 participants in Durham, North Carolina and evaluates the subsequent associations between placental PFAS exposure and birth outcomes (e.g., infant birth weight, gestational age). A total of 11 PFAS were measured in placental tissues collected in 2010-2011, and the compounds PFOS, PFOA, PFNA, and PFDA were detected in all placenta samples. A few placental PFAS were associated with birth outcomes. The most striking result was that placental PFOS was associated with changes in birth weight, but the direction of change depended on the sex of the infant. For male infants, placental PFOS was associated with lower birthweight, and in female infants, placental PFOS was associated with higher birthweight.
In Chapter 3, the exposure to PFAS through drinking water is evaluated in a community with known PFAS water contamination. This chapter includes data on PFAS concentrations in blood serum and drinking water samples from 49 participants in Pittsboro, North Carolina. The community receives its drinking water from the Haw River, a part of the Cape Fear River watershed. Blood and water samples were collected at two different timepoints to explore temporal variability in contamination. This community was found to have blood levels of PFAS about two to four times higher than the U.S. average. This chapter also includes results on the associations between PFAS blood level and clinical chemistry measurements, such as serum lipids, as indicators of health. Negative associations were found between serum PFOS and PFHxA with decreased electrolytes and decreased liver enzymes. Positive associations were found between serum PFOA and PFHxS with increased total cholesterol and increased non-HDL cholesterol.
In Chapter 4, the effects and toxicokinetics of PFAS in a pregnant rabbit model are evaluated. This chapter includes data from an animal study of 21 pregnant rabbits provided with drinking water that is representative of the PFAS exposure observed in Pittsboro, North Carolina. Rabbits were exposed to this environmentally-relevant mixture of ten different PFAS during and before pregnancy. After exposure, the wastes and tissues were evaluated to measure the PFAS concentration that accumulated. This provided information on where PFAS are distributed in the body after exposure. The liver of the pregnant rabbit was also evaluated to determine if there was an increase in lipids in the liver, or any changes in liver lipid metabolism. For this study, few differences were noted between treated animals and control animals, indicating that the environmentally-relevant dose had little effect on pregnant rabbits. However, due to the lack of PFAS accumulation in blood, tissue, or in wastes, it is likely that the dose of PFAS given through drinking water was too low.
In Chapter 5, the levels of PFAS in indoor house dust were evaluated. This chapter includes data on PFAS concentrations in indoor dust from 184 homes in Durham, North Carolina, as well as 49 fire stations across the U.S. and Canada. House dust and fire station dust PFAS concentrations were then evaluated for associations with characteristics of the building (e.g., square footage, amount of carpeting, age of building construction). Levels of precursor PFAS, such as fluorotelomer alcohols, were typically higher in dust than the perfluoroalkyl acids. This study, along with previous literature, shows that the legacy PFAS in dust has been decreasing, but the precursor PFAS has been increasing in U.S. house dust. Few associations were found between building characteristics and dust PFAS. However, one notable result was that higher 8:2 FTOH was found in dust from buildings with more carpeting, indicating that carpets may be an important source of exposure to fluorotelomer alcohols (possibly from stain-proofing treatment).
Collectively, this dissertation provides important information on the potential exposure and health effects of PFAS in North Carolina communities.
Item Open Access Exceeding the Threshold: Analysis of Public Information Transfer using Instrumental Variables(2014-04-16) Inder, GabrielleThis paper examines how information transfer about contamination levels found at brownfield sites capitalizes into nearby property values. More specifically, a hedonic model is used to test the impact on housing transaction prices when a binary measure (i.e. exceeding a threshold or not) or a continuous measure (i.e. chemical levels) is used. In the analysis, I exploit the variation in the contaminant thresholds, caused by regulatory conditions defined by the state of Massachusetts, holding the contaminant level constant. As thresholds are tied to neighborhood attributes in areas surrounding brownfields, threshold exceedance is potentially correlated to unobserved factors that impact housing values. An instrumental variables approach is used to create variation in threshold exceedance through the use of an instrument that measures the presence to underground aquifers. After instrumenting for threshold exceedance, my estimates indicate that a 10.8% decrease in housing values occurs when a contaminant threshold is exceeded, while the continuous measures of toxicity indicate a negative but insignificant effect. These findings suggest that policy makers should consider information conveyance when creating policies to inform homeowners of pollution presence, as improved information provision may increase public awareness about local environmental concerns.Item Open Access Impacts of Governors’ Early-life Heatwave Experiences on Local Environmental Performance(2023-04-28) Li, JiahuanAs a main outcome of climate change, heatwave events have increasingly caused both physical and psychological trauma to human beings. This research investigates the mental influence of early-life heatwave experiences on the personalities of top managers and the subsequent impact on organizational performance. Specifically, the study examines whether public sector governors with early-life heatwave exposure promote local environmental outcomes during their tenure. Employing an ordinary least-squares (OLS) approach, the empirical analysis utilizes two unique datasets comprising the biographical experiences of 4018 municipal governors over the past 50 years and the pollution levels of 288 cities between 2000 and 2016. This study provides clear and robust evidence that early-life heatwave exposure significantly reduces jurisdictional CO2 emissions by 1.1% and PM2.5 pollution by 2.1%, despite variations in heatwave criteria. These findings supplement the top management literature and challenge the current belief of the public unawareness of climate change.Item Open Access Making and Unmaking of Guiyu: The Global Center of E-waste(2021-06-01) Feng, YuqiaoAs the industry of electronic devices rapidly develops, the disposal and recycling of e-waste become an issue at stake. Despite the constant effort of both governments and Non-Governmental Organization, exportation to developing countries remains one of the major approaches for the first world to dispose their hazardous e-waste. Developing countries in Asia and Africa are such perfect destinations for e-waste dumping for their cheap labor and the lack of environmental regulation. Without adequate precaution and proper handling guide, human health and environmental integrity are under threat in these areas. China, being the largest electronics manufacture country, aside from dealing with the considerable amount of domestic e-waste, also faces multiple challenges in regulating the importation of e-waste. In addition to discuss the historical background, current situation, and possible future of e-waste trading on a global level, this project focuses on Guiyu, China, a small southern town which is considered one of the largest e-waste centers in the world. Taking Guiyu as an example, this paper aims to reveal the complexity surrounding the disposal and recycling of e-waste and the potential harm on human health of informal recycle activities. Tracing back the history of e-waste trading in Guiyu helps understand the how did the business become dominant industry. The economic and social context and the shared cultural belief of Chaoshan people also play key roles in the local e-waste recycle development. The paper suggests possible upstream and downstream solutions as well. The paper relies on secondary sources including academic journals, local newspaper, and public documents. Visual and audio material such as documentaries and interview footages are also important resources for the project. Related works that had been conducted within the Chinese language sphere are important sources for this project. To combine local perspective in the process of research, the paper largely depends on articles and official reports that are written in Chinese. Due to the difficulty in obtaining reliable and objective report on the result of the industrial park in Guiyu, the future of Guiyu and its e-waste business remains uncertain.Item Open Access Mercury Capture in North Carolina as a Co-Benefit of Phase II of the Acid Rain Program(2006) Quinlan, Paul JMercury emissions from coal-fired power plants pose environmental and public health concerns in North Carolina. Once converted to methylmercury in aquatic environments, mercury compounds can bioaccumulate in fish and other species, including humans. In humans, mercury compounds can function as a neurotoxin to a fetus and impair neurological development of young children. Recent multi-pollutant strategies are expected to reduce the amount of mercury emitted from coal-fired power plants in North Carolina. To test this assumption, this study examines the mercury capture of a similar piece of existing legislation, the Acid Rain Program. Holding other variables constant, this study finds that during the Phase II years of the Acid Rain Program, coal-fired power plants emitted on average 208 fewer pounds of mercury per year compared to the Phase I years. These results suggest multi-pollutant strategies can be an effective strategy to reduce mercury emissions.