Objective: To examine state‐level environmental inequality trends over time by constructing a new, longitudinal data set and comparing change in environmental and economic inequality.

Methods: We use Environmental Protection Agency's (EPA) RSEI (Risk‐Screening Environmental Indicator) database to create measures of exposure to industrial air toxins and inequality in exposure by race and poverty status. Measures were calculated for each of three periods: 1990–1994, 2000–2004, and 2010–2014.

Results: Exposure declined but inequality persisted. The geographic patterns displayed by race‐ and poverty‐related environmental inequality differ. But, states with higher levels of race‐based inequality had higher levels of exposure. Poverty‐based environmental and economic inequality exhibited a moderate, positive relation that was spatially patterned.

Conclusion: While environmental quality improved, we saw little progress in reducing environmental inequality. Though both race‐ and poverty‐based inequality remain, they result from different mechanisms. Future research should examine the relations between deindustrialization and economic, environmental, and political inequality.