The 2026 "State of the Air" report from the American Lung Association showed soot and smog levels in Indiana do not paint a healthy picture.

Emissions data taken between 2022 and 2024 found several counties received "C," "D," and "F" grades.

Tiffany Nichols, director of advocacy for the American Lung Association, said as the weather gets warmer, it's important to know the air quality before spending time outdoors.

"The Indiana Department of Environmental Management puts out what's called No Zone Action Days," Nichols explained. "On days when the air is bad, we encourage you to wear an N95 mask and also limit the time outdoors, especially if you don't want to wear a mask for yourself or your children."

Indiana’s major interstates – I-465 and I-70 – are heavily used by motorists and diesel truck drivers and can produce high rates of emissions. The highways run through and around most major Indiana cities, Nichols pointed out, making certain communities more vulnerable to pollution.

Smog is ground-level ozone pollution and soot is particulate matter. Both can cause a host of health problems, including premature deaths and births, respiratory illnesses, strokes and mental decline.

As the data center tug-of-war continues in Indiana, one recurring concern among Hoosiers has been the environmental impact of the facilities. Nichols noted the American Lung Association receives regular inquiries from residents about whether these data centers could increase contaminant levels.

"Data centers can be another source of pollution," Nichols stressed. "We encourage those that are looking to put data centers in certain communities or all communities that they work with those communities and that they use renewable zero-emission energy sources to power them."

Another influence on Indiana's air quality was the 2025 Canadian wildfires. The Indiana Department of Environmental Management issued a statewide Air Quality Action Day in late June as winds carried smoke into the Midwest.

Source: Public News Service