2020 Yes https://doi.org/10.3390/ijerph17186931 Mullen, Casey North America Observational Epidemiology Study Exposure Study Students Elementary (K-5) Particulate Matter (PM) Test Performance Air pollution PM 2.5 Environmental jsutice Primary schools Academic proficiency Salt Lake County, Utah Study of 156 Utah schools examined third-grade test scores relative to chronic and peak PM2.5 exposure. Higher pollution linked to reduced math and ELA proficiency, with stronger effects in advantaged schools.