| The effects of uranium in unusually exposed subpopulations have not been thoroughly investigated. The purpose of this dissertation was to assess the impact of environmental uranium exposure on chronic health outcomes in subpopulations living near uranium processing facilities or living in geographic areas with elevated groundwater uranium concentrations.;The first objective was to perform an ecologic assessment of groundwater uranium levels and chronic health outcomes in South Carolina (SC). SaTScan cluster analyses and linear and semiparametric regression models were used to evaluate the relationship between uranium levels and chronic health outcomes.;The second objective was to assess the impact of living near the Fernald uranium processing facility. Multiple logistic regression and analysis of variance were used to evaluate the relationship between uranium levels and hypertension or hematologic parameters.;For colorectal, breast, and kidney/renal pelvic cancers, census tracts (CT) with elevated groundwater consumption and uranium concentrations had increased rates of cancer, especially for CTs populated primarily by African Americans (AAs) (all p<0.05). Alternatively, a statistically significant increased risk for total (p=0.03) and prostate cancer (p=0.04) was found for CTs more heavily populated by European Americans. Several CT clusters were identified in the north and northeast regions of SC that had both elevated uranium concentrations (p<0.05) and elevated bladder, kidney disease, or kidney stone hospitalization rates (p<0.05). A dose-response relationship between groundwater consumption and the effect of elevated uranium concentration on disease risk was observed.;Fernald residents with higher uranium exposures had elevated systolic blood pressures as compared to individuals with lower uranium exposures (p=0.05). For hematologic parameters, individuals with higher uranium exposures had increased eosinophil counts (p=0.03), and decreased lymphocyte counts (p=0.01). When models were stratified by gender, increased systolic blood pressure and eosinophil counts, as well as decreased lymphocyte counts, were detected among women with elevated uranium exposures (all p<0.05), but not among men.;The results of this dissertation support hypotheses linking exposure to environmental uranium with adverse health outcomes. Disparities in the impact of uranium on health outcomes may exist; AAs and women were most affected by uranium exposures in our SC and Fernald studies, respectively. |
