Assessing the legacy of redlining on spatial inequities in social and environmental determinants of health

Although housing discrimination was outlawed in the United States in 1968, historic redlining remains a driver of racialized inequities in environmental health. However, there are many aspects of environmental health that are not yet well-understood in relation to redlining. We investigated the legacy of redlining on social and environmental determinants of health and the spatial distribution of these relationships across Baltimore and Philadelphia. We use publicly available spatial data sources on sociodemographics, built environment, housing, mobility, and arrests to understand the distribution of determinants of health given historic redlining. Multiscale geographically weighted regression was implemented to measure the relationship between these dimensions and redlining grades. While we identified strong, spatially heterogenous relationships between redlining and social and environmental determinants of health, for nearly all determinants of health, we observed the most adverse characteristics in “C” tracts, indicating a yellow-lining effect. Meanwhile, redlined tracts in both cities exhibited a mix of built environment characteristics, including higher levels of walkability, housing density, renter-occupied housing, and vacancies. Our findings suggest that while redlining has played a role in shaping neighborhood conditions, other factors, such as ongoing disinvestment and neighborhood transformation processes are likely influential in determining current social and environmental determinants of health. • Most adverse social and environmental determinants of health in yellow-lined (“C”) tracts. • GIScience methods are applied to investigate associations between redlining and urban built environments. • Strong, spatially heterogenous relationship between redlining and determinants of health. • Other racialized neighborhood change processes may attenuate the relationship between redlining and health.