Freakonomics Radio

As the Trump administration rolls back environmental regulations, we revisit a 2022 episode that explored the hidden cost of an invisible threat: air pollution.   SOURCES: Angela Duckworth, psychologist at the University of Pennsylvania. Michael Greenstone, economist at the University of Chicago, director of the Energy Policy Institute, co-director of the Climate Impact Lab. Stephan Heblich, economist at the University of Toronto. Andrea La Nauze, economist at Deakin University. Steve Levitt, professor emeritus of economics at the University of Chicago. Edson Severnini, economist at Boston College.   RESOURCES: "Most Polluted Cities," (American Lung Association, 2026). "Air Pollution and Adult Cognition: Evidence from Brain Training," by Andrea La Nauze and Edson Severnini (Journal of the Association of Environmental and Resource Economists, 2025). "Air Pollution and Student Performance in the U.S.," by Michael Gilraine and Angela Zheng (NBER Working Papers, 2022).