Date on Master's Thesis/Doctoral Dissertation
Epidemiology and Population Health
Public Health Sciences with a specialization in Epidemiology, PhD
Committee Co-Chair (if applicable)
children's health; environmental epidemiology; particulate matter; metal exposure; cognitive control
The use of coal combustion for electricity and the storage of coal combustion by-products known as coal ash occur across the United States and around the world. The most abundant type of coal ash, fly ash, contains small particles with metals, some of which are known neurotoxins. Fly ash is currently stored in open-air landfills and surface impoundments that allow fugitive dust to escape into surrounding communities, potentially exposing children to small neurotoxic particles. This dissertation uses preliminary data from a larger cross-sectional study to investigate the relationship between particulate matter exposure, metal exposure, and problems with self-regulation. Recruitment of this study sample, the first 78 of 300 participants, occurred between September 2015 and December 2016. Exploratory spatial data analysis was used to assess how living near fly ash storage is related to indoor particulate matter concentration and exposure to metals. Linear regression models were used to assess the relationship between fly ash exposure, particulate matter exposure, and self-regulation. Furthermore, Bayesian kernel machine regression for variable selection and regression models were used to explore the relationship between metal concentration in particulate matter and children’s self-regulation. The most abundant metal found in fly ash particles was aluminum. The concentration of aluminum in indoor PM10 was significantly related to distance from the fly ash landfills and an Environmental Justice Index used to identify vulnerable populations. In addition, children with higher aluminum exposure were found to perform more poorly on the Behavioral Assessment and Research System Continuous Performance and Selective Attention Tests, indicating general inattention problems. These results are based on a small preliminary sample and should therefore be interpreted with caution. Future studies will further investigate the relationship between aluminum exposure, children’s metal body burden, and cognitive control.
Sears, Clara G., "The particulars about particulates : metal exposure and self-regulation of children living near coal ash." (2017). Electronic Theses and Dissertations. Paper 2699.