Voronoiapp.com collaborated with HouseFresh to identify the cities and towns in America with the worst air quality.

To do this, they sourced the average PM2.5 concentrations from IQAir for all available U.S. cities and towns in 2024.

Then, they identified the city/town in each state with a population of over 10,000 people with the highest average yearly PM2.5 concentration in 2024...

Worst was Shafter, California, with an air quality that is equivalent to smoking 267 cigarettes per year.