Criteria air pollution and marginalized populations: Environmental inequity in metropolitan Phoenix, Arizona

Our objective is to examine spatial relationships between modeled criteria air pollutants (i.e., nitrous oxides, carbon monoxide, and ozone) and sociodemographics in metropolitan Phoenix, Arizona. Modeled air pollution offers environmental justice researchers a new and robust data source for representing chronic environmental hazards. Methods. We used multiple regression equations to predict criteria pollution levels using sociodemographic variables at the Census block group level. Results. We find that Census block groups with lower neighborhood socioeconomic status, higher proportions of Latino immigrants, and higher proportions of renters are exposed to higher levels of criteria air pollutants. Proportion African American, however, is not a significant predictor of criteria air pollution in the Phoenix metro area. Conclusions. These findings demonstrate clear social-class and ethnic-based environmental injustices in the distribution of air pollution. We attribute these patterns to the role of white privilege in the historical and contemporary development of industrial and transportation corridors in Phoenix in relation to racially segregated neighborhoods. Although all people are implicated in the production of criteria pollutants, lower-income and ethnic-minority residents are disproportionately exposed in metropolitan Phoenix.