Beyond redlining: Gentrification, displacement, disadvantages, and exclusivity predict urban environmental and health inequities

This study investigated environmental justice by developing and comparing four contemporary urban segregation typologies (persistent exclusivity, persistent disadvantage, recent gentrification, and recent displacement-hosting) with historical Homeowners' Loan Corporation (HOLC) zones and 104 variables spanning the natural and built environments, pollution, environmental hazards, health, and disability. We applied principal component analysis to the 2010 and 2020 American Community Survey and the US Census data to derive neighborhood typology indices for 342 tracts in Portland, Oregon. Using Spearman's correlation and end-member comparisons, we assessed relationships among the typologies, HOLC zones, and environmental and health outcomes. HOLC zones predicted persistently exclusive areas in the urban core but not current injustices elsewhere. Persistently exclusive neighborhoods, both within and outside HOLC zones, had more tree canopy, less dense development, lower disaster risks, better preventive care, and fewer diseases than other areas, but more air pollution exposure. Recently gentrified areas had more transit and community resources but worse heat exposure, pollution, and impervious surface coverage and aligned strongly with HOLC C and D zones. Recent displacement-hosting neighborhoods were cleaner and greener but lack transit and community resources, while exhibiting weak health outcomes. Persistently disadvantaged areas, often outside HOLC zones, faced the most severe conditions, including minimal access to nature, aging infrastructure, the highest pollution and hazard exposure, and the worst health outcomes and disability rates. Our study offers insights into the spatial mechanisms of urban inequities and well-being, underscoring the need to look beyond redlining to fully understand and address today's social and environmental injustices.