Project Summary/Abstract The diversity supplement submission aims to fund Ms. Kelli Williams' participation in an environmental epidemiology study to gain knowledge about the design, conduct, and analysis of epidemiological research for environmental toxins in children, and to contribute her expertise in the social determinants of health combined with her enthusiasm for increasing diversity in research to the overall process by developing and conducting an ancillary study. Ms. Williams is currently enrolled in the Epidemiology PhD program at the University of Pennsylvania and is not funded by any other NIH grant. Some environmental chemicals of concern to children are polybrominated diphenyl ethers (PBDEs) and organophosphate esters (OPEs). PBDEs hyperactivity, shown particulates affects and of neurodevelopment ongoing prospective PBDEs assess modification health retardant using Holmes, minority are linked to memory issues, and cognitive impairment, disrupting vital t hyroid ormones. OPEs have been to have neurotoxicity and behavioral effects in animals and some human studies. Children exposed t o experience sleep disturbances, and sleep is crucial for proper neurodevelopment; its deficiency cognition, psychosocial development, and mental health. Research gaps exist regarding how prenatal postnatal PBDEs/OPEs influence U.S child sleep health and neurodevelopment with social determinants health (SDOH) considerations. No prior studies explore these chemicals' roles in sleep health-mediated and their SDOH interactions. Filling this gap demands epidemiological studies through an birth cohort assessing environmental toxicants ffects on human neurobehaviors. Through a pregnancy and birth cohort study, we will: 1) investigate the associations between pre/post-natal and sleep health; 2) investigate the associations between pre-/post-natal OPEs and sleep health; 3) the mediation effect of sleep health and PBDEs/OPEs on neurobehavior; and 4) determine the effect of specific SDOH between PBDEs/OPEs and sleep health and neurobehavior. Ms. Williams has an immense interest and background in population-research, social determinants of research. She will design and complete her doctoral issertation assessing the impact of prenatal flame- exposure on sleep health, neurodevelopment, and social determinants of health factors in children, innovative analysis techniques, under the guidance of her mentors, Dr. Aimin Chen and Dr. John with a goal of an independently unded research career to improve various disease outcomes for and/or underserved populations. h e d f