Date on Master's Thesis/Doctoral Dissertation


Document Type

Doctoral Dissertation

Degree Name

Ph. D.


Epidemiology and Population Health

Degree Program

Public Health Sciences with a specialization in Epidemiology, PhD

Committee Chair

Zierold, Kristina

Committee Co-Chair (if applicable)

Baumgartner, Richard

Committee Member

Baumgartner, Richard

Committee Member

Baumgartner, Kathy

Committee Member

Sears, Lonnie

Committee Member

Brock, Guy

Author's Keywords

fly ash; metal exposure; neurobehavioral disorders; children's health


Introduction: Coal ash, generated from the combustion of coal is principally made up of fly ash, which consists of small particles and metals that can affect the development of children. Coal ash is predominately stored in landfills and surface impoundments, of which many are in proximity to residential areas. According to the Environmental Protection Agency, 25% of residents in proximity to electric power plants are children. Few studies have reported a positive association between coal ash and its by-products and neurobehavioral disorders. The purpose of this study was to explore the relationship between coal ash and its components and behaviors underlying autism that includes social, thought, and obsessive-compulsive problems. Methods: Analysis addressed filter fly ash, lift tape fly ash, and combined filter and lift tape fly ash. Body and home metal concentrations were derived from metals found in nails and filters, respectively. Fly ash from lift tape and filter were measured using Scanning Electron Microscopy (SEM) and Energy-Dispersive X-ray Spectrometry (EDX), while the metals found in nails and filters were measured using Proton Induced Emission X-ray (PIXE). Scores from the Child Behavior Checklist were analyzed to assess social, thought, and obsessive-compulsive problems. Logistic regression models, rank sum tests, and correlation tests were used to assess the relationship between fly ash and metals, and social, thought, and obsessive-compulsive problems. Results: There was no statistically significant association between the outcomes and fly ash measures. Results from this research suggest that increased copper levels may be associated with the development of social problems in children (Odds Ratio (OR)=5.44, 95% Confidence Interval (CI)=1.07-27.6). We also found that exposure to an aggregate of all metals was most strongly associated with thought problems with a linear dose response relationship (OR=8.80 for tertile 2; OR=30.2 for tertile 3; PtrendConclusion: Pollutants such as fly ash and metals found in coal ash may affect the behavior of children and need to be further studied. Future research is needed to further understand the etiology between behaviors underlying ASD and environmental factors.

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Epidemiology Commons