7. PROJECT SUMMARY This individual NRSA will provide mentored training in children?s environmental health for Kelsey Dzwilewski. Ms. Dzwilewski has completed coursework in neurotoxicology, developmental psychology, and statistics, and has initiated a research project assessing the effects of prenatal environmental exposures on neurodevelopment during infancy. This award would allow her to complete further coursework in epidemiology, and complete her thesis project under the guidance of an exceptional mentor team with expertise in neurotoxicology, environmental health, epidemiology, and biostatistics. The potential for adverse impacts of prenatal exposure to phthalates and bisphenol A (BPA) on neurodevelopment is a growing public health concern. Replacement chemicals such as bisphenol F (BPF) and bisphenol S (BPS) with similar chemical structures are being introduced; however, relatively little is known about their potential impacts on neurodevelopment. While previous studies have shown adverse impacts of prenatal exposures to phthalates and BPA on global measures of cognition, behavior, and social outcomes during childhood, results have varied across populations, sexes, and outcome measures. Furthermore, very few studies have assessed the impacts of these exposures on specific cognitive domains or measured neurodevelopmental outcomes early in life. This research will take place in the context of an ongoing prospective birth cohort study. Ms. Dzwilewski will use data she is collecting in the context of this study to assess the impacts of prenatal exposure to phthalates, BPA, and replacement chemicals on working memory, attention, and information processing speed at 7-8 months of age (Aim 1). The impact of exposures on face processing will also be assessed (Aim 2). This project will build on research illustrating that infant looking behaviors can be used as stable, reliable measures of basic cognitive processes. Moreover, the study will use infrared eye tracking to assess the impacts of phthalates and bisphenols on these specific domains in finer detail than has been possible with more traditional infant testing techniques. Looking behaviors will be assessed while infants view photographs of human faces and include novelty preference (a measure of working memory), average shift rate between simultaneously-presented stimuli (a measure attention), and average fixation duration (a measure information processing speed). The ratio of time spent looking at the eyes compared to other regions of the face will be used as a measure of face processing. Prenatal exposures will be measured via maternal urinary phthalate metabolites and total bisphenols in a pooled samples of urines collected across pregnancy, providing a stable estimate of exposure throughout the prenatal period. It is hypothesized that prenatal exposure to phthalates, BPA, and their replacements will be associated with adverse impacts on working memory, attention, information processing speed, and/or face processing. These findings will provide novel information regarding the impact of these ubiquitous environmental toxicants on neurodevelopment early in life.