Digital Commons Network^™

Arsenic : Risk, Exposure, Policy And Management, Nadia Binte Jamil

Theses, Dissertations and Culminating Projects

Arsenic (As) contamination in drinking water is a global concern. About 150 million people from 70 countries in the world are at risk to health hazards associated with As contamination. In this study, we compared four As mitigation approaches practiced in Bangladesh and their costs. Our results show that intervention that is associated with the lowest cost of exposure reduction is testing and switching ($3/person), followed by intermediate wells ($28/person), deep tube wells ($143/person), and piped water supply system ($158/person). We then prioritized affected villages to reduce exposure and facilitate mitigation using three criteria: weighted exposure (mean As concentration x …

Responses Of The Symbiotic Sea Anemone Anthopleura Elegantissima To Microplastics, Robert Beck

WWU Graduate School Collection

The Salish Sea, a large and complex fjord estuary, receives waters impacted by a watershed that includes 8 million people aggregated in several large urban and industrial centers. Microplastics, defined as plastic particles less than 5 mm in their largest dimension, are transported from this watershed into the Salish Sea where they are easily ingested by filter feeders, herbivores and predators. To measure effects of microplastics on one common and important intertidal species, we exposed the sea anemone Anthopleura elegantissima to polyester microfibers at concentrations of 0, 0.01, or 0.1 g/L in the laboratory and measured the responses of the …

Addressing Uncertainties Of Polychlorinated Biphenyls In Schools, Alice Fan

Master's Projects and Capstones

Despite the potential neurological health deficits resulting from polychlorinated biphenyls, there is a lack of inhalation studies and regulations to protect students and teachers who are widely exposed to PCBs in older (1950 to 1979) schools. To estimate the extent of PCB detections in Los Angeles County schools, I applied a mathematical model to estimate the range of PCB detections in schools built between 1950 and 1984. I estimate the range of 17-34% PCB detections of open schools within Los Angeles County. Next, I reviewed exposure tools provided by the US EPA to bridge the uncertainty gaps between ingestion and …

Particles In Welding Fumes, Rebecca T. Williams

USF Tampa Graduate Theses and Dissertations

The purpose of this study was to investigate whether or not differing base metals and filler wires used during welding processes contributed to differing amounts of ultrafine particles (UFP) and nanoparticles being emitted during the welding procedure. The study was also conducted to determine UFP and nanoparticle exposure in the breathing zones of the welders as well as the breathing zones of pipefitters and fire watchers, who commonly sit 6ft behind the welding arc. In order to determine if UFP and NP exposures differed with base metal and filler wire, all welding processes utilized the same welding machine for metal …

Polychlorinated Biphenyl (Pcb) Pollution Of The Hudson River: Social Policy And Health Considerations, Laura Schad

Honors Theses

The purpose of this paper is to examine pollution in the Hudson River and the role General Electric has had in creating this problem. The focus will be on social issues and problems that have emerged as a result of the environmental damage from pollution. Until recently, there was little research done on the health and environmental justice issues that impact the New York communities where GE’s factories were located. This paper examines the material collected and studies that were done which document Hudson River pollution and the contributions as well as cleanup efforts of General Electric. The overall problems …

Preserving Biodiversity For A Climate Change Future: A Resilience Assessment Of Three Bay Area Species--Adenostoma Fasciculatum (Chamise), Arctostaphylos Canescens (Hoary Manzanita), And Arctostaphylos Virgata (Marin Manzanita), Alison S. Pollack

Master's Projects and Capstones

Anthropogenic climate change is an undeniable threat to the future of the natural world and human civilization. These shifts will have profound impacts on vegetation, especially for species endemic to isolated regions or sensitive to climate change factors. However, species resilience can predict success into the next century. Resilience is defined as the ability to withstand climate change factors, whereas vulnerability is defined as susceptibility to climate induced stress or damage.

Chaparral and coastal scrub ecosystems within the Bay Area of California provide a unique context for examining resilience, as many species are adapted to high temperatures, drought, and wildfire—all …

An Analysis Of The Influences On Household-Level Adaptations To Environmental Hazards, Tiia Maria Carraway

LSU Master's Theses

Utilizing a randomized phone survey of coastal Louisiana residents, this study will focus on identifying which influences from a resident’s exposure, socio-economic vulnerability and adaptive capacity are the best indicators of an individual’s resilience. Two binary logistic regression models were developed to test the associations of resident response to: 1) acute hazards via household emergency plan adoption and 2) chronic hazards represented by behavior modification in response to daily air quality reporting where adoption of these two risk-reducing behaviors are viewed as increased individual resilience. Bivariate correlation analysis found that a north – south grouping of coastal Louisiana was significantly …

Geography Of Pestecide Exposure In The Lower Valley (El Paso County, Texas), Critina Solis Sanchez

Open Access Theses & Dissertations

Previous studies using GIS have been used to understand the demographics of particular areas of a city and the risks associated with living there. In the Lower Valley (Socorro, Clint, and San Elizario) area of El Paso County (TX), there has been a rapid growth in population. This increase in growth has led to this project about the types of pesticides used in farms and if they are creating possible health risks for people living in this area and which populations are most at risk. To determine population risk, I use existing GIS information, specifically a USDA aerial photograph taken …

Uncertainty Analysis In Ecological Risk Assessment Modeling, Tepwitoon Thongsri

Dissertations

A probabilistic approach employing Monte Carlo simulations for assessing parameter and risks as probabilistic distributions was used in an ecological risk assessment (ERA) model to characterize risk and address uncertainty. This study addresses the following sources of uncertainty: parameter inputs in the ERA models, risk algorithms and uncertain input concentrations. To achieve this objective, both sensitivity and uncertainty analyses are being conducted. Monte Carlo simulations were used for generating probabilistic distributions of parameter and model uncertainty. All sensitivity, uncertainty, and variability analyses were coded in Visual Basic as part of the ERA model software version 2001, which was developed under …