This City Has America's Cleanest Air

The air cleared over many of the world’s largest cities over the course of the COVID-19 pandemic. Factories shut down and their emissions temporarily disappeared. People stopped driving cars because there was nowhere to go.

However, the long-term future of clean air remains at grave risk. Millions of people die each year from air pollution-related illnesses. Most of the blame for these deaths comes from remarkably dangerous air in the large cities of China and India. America is not blameless, though.

The new American Lung Association 2021 “State of the Air” report indicates that “millions of people are living with and breathing polluted air, placing their health and lives at risk.” The report rates cities and states. The three primary measurements are based on ozone, year-round particle pollution and short-term particle pollution.

The American Lung Association also picked what it considers the cleanest cities, based primarily on ozone, which Climate Central defines as “a pollutant which forms when heat and sunlight allow the reaction of two other pollutants: nitrogen oxides and volatile organic compounds.” The cause of these, Climate Central experts add, are “chemicals which come from industrial plants, electric utilities, vehicle exhaust, wildfire smoke, and oil and gas extraction.” The other factors are year-round particle pollution and short-term particle pollution.

The cleanest city in America is Altoona-Huntingdon, Pennsylvania. It is located about halfway between the Pittsburgh and the New Jersey border. It is followed on the American Lung Association list by Bangor, Maine, and Bismarck, North Dakota.

Click here to read about the 30 most polluted places on Earth.