ST. LOUIS — On the first day of summer, St. Louis experienced its first orange-level air quality rating of the season.

The orange-level rating is based on the U.S. Air Quality Index. During such advisories, members of sensitive groups may experience health effects, but the general public is less likely to be affected.

At-risk groups include people with lung disease, children, older adults, and those who are active outdoors (including outdoor workers). Prolonged or heavy outdoor exertion should be reduced. Doctors say when the heat index is high, there is more ground-level ozone and more particular matter in the air. When that goes into your lungs, it can cause inflammation.

Community groups say there are things people can do to improve the air quality, like taking public transit, carpooling, vanpooling, walking, biking, or working from home instead of driving in single-occupancy vehicles.

If you’ve been hesitant to take public transit, Kim Cella with the Citizens for Modern Transit says now is the time to give it a try. She and the group recently launched a campaign called “Don’t Pollute. Switch Up Your Commute.”

“Transit is a great way to get you there, whether for work or for play, and people need to realize that it’s very simple to give it a try,” said Cella. “Look around. U.S. gas prices are nearing $5 a gallon. Look at what your choices are, public transit. A monthly pass is $78. That can be a tank of gas in your car depending on what you drive. Think about it.”

To learn more about accessing public transit in the St. Louis area, visit https://cleanair-stlouis.com/commute/. The site also has information about carpooling, vanpooling, and ride-matching services.