Reassessing environmental justice through pollution substitution

Growing evidence shows that pollution released to environmental media, such as waterways and land, has increased while air pollution has declined due to stringent regulation in the United States. Such pollution substitution may disproportionately occur in disadvantaged communities, but little research has investigated the extent to which pollution substitution is correlated with communities’ characteristics. Using spatial panel data of toxic release during 1990–2010 and the ethnic diversity index to measure a community's social cohesion and the ability for collective action, we found that pollution substitution is positively associated with greater ethnic diversity, regardless of population size. Moreover, lower ethnic diversity (higher potential of collective action) in adjacent communities increases pollution substitution from air to land in the home community. Our findings suggest that the degree of environmental inequity should be assessed by considering pollution released to all environmental media.