Environmental Radiation and Fetal Outcomes: From the Ground to the Sky

Abstract

Background radiation is an environmental risk factor for human diseases that is often overlooked. This dissertation focuses on two major ionizing radiation exposures that occur naturally at chronic and low doses, particle radioactivity (the radioactive property of particulate matter in the air) and solar activity (changes on the Sun’s surface), and their association with fetal outcomes. The association of particle radioactivity with ultrasound fetal growth parameters was investigated in the first chapter, and solar activity was considered as the exposure of interest in the second chapter. Lastly, the third chapter explores and discusses the association found between solar activity and live births. Overall, particle radioactivity and solar activity were found to be harmful to fetal growth, though the direction and magnitude of their associations varied by exposure. There was also evidence that solar activity exposure may be related to fewer live births, with at least some of which were through pregnancy losses. Future work is needed to understand the clinical and public health implications of the findings.