Pollution levels factor in households’ decision to relocate within the United States, but only richer households can afford areas with improved air quality, a new study finds. Researchers analyse detailed origin and destination information of relocating households, rather than just aggregate migration flows, and uncover a direct link between a household’s income and their new chosen county of residence. They find inequalities exist when it comes to who is exposed to the worst areas of pollution — with poorer families hit hardest. Richer households opt to move into cleaner, healthier areas that tend to be more expensive. However poorer families are priced out of these counties and are the ones who move into areas with higher levels of toxic releases.