Neighborhood characteristics such as deteriorating housing, crime levels and rental instability can affect human health, from changes in weight to accelerated cellular aging. We are an interdisciplinary research team working within ELEMENT (Early Life Exposures in Mexico to ENvironmental Toxicants), an ongoing, 20-year birth cohort that has collected biological samples and physical assessments from 600 mother-child pairs located throughout Mexico City. Recently, detailed ethnographic information has been collected on ELEMENT families and neighborhoods, which will allow us to examine how housing turnover and insecurity affect susceptibility to environmental chemicals and influence anthropometry and molecular measures of health (DNA methylation, telomere length). By linking molecular, epidemiological, and environmental information to ethnographically observed neighborhood conditions we can investigate how neighborhoods get under the skin.