The Pima County Department Environmental Quality has issued a warning for an elevated potential for ground-level ozone air pollution in the Tucson metro area for today, May 26.

“People who are sensitive to air pollution may experience shortness of breath, coughing, throat irritation, wheezing, and breathing discomfort,” said a department press release.

Individuals who are sensitive to ozone should limit time outside doing extraneous activities particularly in the afternoon when elevated ozone levels are likely to occur. Exercising outdoors during this time and breathing deeply can cause ozone to penetrate the lungs more rapidly.

Ozone pollution is caused by vehicle exhaust, industrial and power plant emissions, gasoline vapors, paint, gasoline-powered landscaping equipment, and chemical solvents, as well as natural sources like wildfires. The department said some vegetation “emit oxides of nitrogen and/or volatile organic compounds that form ozone after a photochemical reaction occurs with intense sunlight and heat.”

Humans can take a variety of actions to reduce emissions that contribute to this problem. The department suggests the following:

1. Reduce driving by combining errands into one trip.

2. Avoid idling a vehicle’s engine. Instead of sitting in a long drive-thru line, park, and go inside.

3. Refuel your vehicle after 6 p.m. when fumes are less likely to form ozone.

4. While refueling, always stop at the click to avoid spills and overfilling the gas tank.

5. Make sure your gas cap is tightly sealed.

6. Check your tire pressure monthly to reduce gasoline use.

7. Use low VOC or water-based paints, stains, finishes, and paint strippers.

8. Avoid using gas-powered landscaping equipment.

9. Conserve electricity to reduce emissions from power plants.

Children, adults who are active outdoors, people with respiratory diseases, and individuals with an “unusual sensitivity” are most sensitive to ozone pollution. Pima County encourages individuals who are feeling symptoms to seek medical attention if necessary.