Advancing Methods and Models that Promote Equity in Ambient Air Quality

Several groups in the United States, including communities of color and low-income communities, are frequently disproportionately exposed to ambient (i.e., outdoor) air pollution, reflecting unjust placement of emission sources, systemic bias, and historic race-based land use planning. Eliminating these inequities is critical for advancing environmental justice. This review synthesizes methodological innovations for characterizing and mitigating ambient air pollution inequities, focusing on the past 10 years, mostly in the United States. Advances in exposure assessment (e.g., empirical models, satellite remote sensing, mobile monitoring, sensor networks) provide new tools for characterizing disparities. Advances in techniques for attributing pollution to specific sources (e.g., reduced-complexity models) reveal how emission-reduction approaches may or may not eliminate disparities. Spatially targeted emission reductions are critical for eliminating relative disparities; conventional approaches (e.g., sectoral emission reductions, national concentration standards) are unlikely to eliminate those disparities. This article provides insights for effective interventions to promote equity in ambient air pollution exposure.