Bartholomew County is one of several southern Indiana locations that will have an Air Quality Action Day Wednesday with high ozone levels predicted.
The Indiana Department of Environmental Management issued the warning for Bartholomew, Brown, Johnson, Jackson, Monroe and Shelby counties, among others.
Ground-level ozone forms when sunlight and hot weather bake vehicle exhaust, factory emissions and gasoline vapors, IDEM officials said. Ozone near the ground is a lung irritant that can cause coughing and breathing difficulties.
To learn more or to monitor Air Quality Action Days, visit smogwatch.in.gov.