Impacts of prenatal phthalate and bisphenol exposure on infant cognition and early language development

The neurodevelopmental impacts of prenatal exposure to endocrine disrupting chemicals including bisphenols and phthalates are a growing public health concern. Bisphenols and phthalates are used in plastic consumer products, food and drink packaging and containers, personal care and household products, medical supplies, and building supplies. Due to their widespread use, exposure is nearly ubiquitous among women of childbearing age and among pregnant women. Epidemiological studies have found associations of prenatal exposure to bisphenol A (BPA) and phthalates with adverse neurobehavioral and cognitive outcomes during early and middle childhood, and there is growing evidence that they may also have detrimental effects on language development. However, results of these studies have varied and only one has assessed the impacts of these prenatal exposures on cognition very early in life. Additionally, replacement chemicals within the bisphenol and phthalate families have recently been used increasingly in consumer products and even less is known about their impacts on neurodevelopment. The goal of this dissertation is to establish an automated cognitive assessment paradigm that can be used to assess infant cognition in environmental epidemiology as well as to examine associations of prenatal exposures to BPA, two of its replacement chemicals, bisphenol F (BPF) and bisphenol S (BPS), diethyl phthalate (DEP), di-(2-ethylhexyl) phthalate (DEHP), and the DEHP replacement chemical diisononyl phthalate (DINP) with infant cognition and early language development. Chapter 3 presents a general profile of the Illinois Kids Development Study (IKIDS) cohort, within which the research presented here was conducted. Chapter 4 demonstrates the feasibility of using state-of-the-art eye tracking technology to adapt a visual recognition memory (VRM) paradigm from developmental psychology studies for use in environmental epidemiology and characterizes infant looking behavior outcome measures that pertain to information processing speed, attention, social cognition, and recognition memory. Chapter 5 examines associations between prenatal maternal urinary biomarkers of bisphenol and phthalate exposure and VRM paradigm outcome measures of infant cognition. Results suggest adverse impacts of prenatal BPF exposure on information processing speed, of prenatal DEHP exposure on attention in males but not females, and of prenatal DINP exposure on recognition memory. Chapter 6 assesses associations between prenatal urinary biomarkers of bisphenol and phthalate exposure and measures of language development in 2-year-old children, and results suggest adverse impacts of prenatal exposure to BPF and DEP on language development. These results offer an approach for assessing infant cognitive development in large-scale epidemiological studies and demonstrates that they are sensitive to the impacts of prenatal exposures on specific cognitive domains. Furthermore, these results add to a growing body of literature showing that prenatal exposure to bisphenols and phthalates may impact cognitive and language development, and demonstrate that replacement chemicals presumed to be less toxic than the chemicals they are replacing may have detrimental impacts on neurodevelopment.LimitedAuthor requested closed access (OA after 2yrs) in Vireo ETD syste