The candidate is seeking a Pathway to Independence Award to provide an intensive research, training and career development program as an epidemiologist and developing investigator at the Stanford University. The long-term goal is to become a leading investigator in the field of environmental perinatal epidemiology with the intention of informing clinical decisions and environmental policy to improve pediatric health. To continue her progress towards this goal, the candidate is proposing a study addressing specific hypotheses of the role of social factors, namely neighborhood deprivation and acculturation, in the relationship between traffic-related air pollution and adverse birth outcomes. The exposures of interest include ambient air pollutants and traffic density. The adverse birth outcomes include structural birth defects and outcomes related to birth weight and gestational age. She will use semi-parametric methods estimate population- level effects with a more causal parameters of interest. She will develop and use indices to characterize neighborhood deprivation and acculturation and investigate these factors as potential effect modifiers. With the use of geographic information systems (GIS) tools and publicly available data, the candidate will characterize the social context of the neighborhood of each participant to gain more insight into the interaction of the physical and social environment in determining health outcomes. The data comprising these indices will be shared via an online database for researchers to use for future studies in the San Joaquin Valley of California. This research supports the National Institutes of Health's mission to prevent disease and improve the health and well-being of Americans and the NIEHS's mission to build integrated environmental health research programs to address the cross-cutting problems in human biology and human disease. With the robust research program that the candidate has proposed, she plan for future training and the strong team of mentors and advisors, and she intends to become an independent researcher and prepare herself to compete for R01 funding to: 1) expand the geographic and temporal range; 2) combine with databases that include additional neonatal outcomes; and 3) create a more rich exposure assessment by collecting more data on additional pollutants such as pesticides and air toxics.