The Minnesota Pollution Control Agency has issued an air quality alert for southern, eastern and portions of central Minnesota, effective from noon to 8 p.m. Friday. The affected area includes the entire Twin Cities metro, Marshall, Rochester, St. Cloud and the Tribal Nation of Upper Sioux.

The air quality index is expected to climb into the orange (unhealthy for sensitive groups) category Friday due to unseasonably warm temperatures, mostly sunny skies and high ozone levels moving in from the southern and central U.S. AQI levels should start out in the yellow (moderate) category this morning, before climbing into the orange category during the afternoon and evening. Conditions are expected to improve around sunset Friday as ozone levels decline.

Some more sensitive than others

There are people who are more likely to be affected when ozone pollution reaches an unhealthy level:

• People who have asthma or other breathing conditions like chronic obstructive pulmonary disease (COPD), chronic bronchitis and emphysema

• Children and teenagers

• People of all ages who are doing extended or heavy, physical activity like playing sports or working outdoors

Some healthy people are more sensitive to ozone even though they have none of the risk factors. There may be a genetic basis for this increased sensitivity.

Health effects

Unhealthy ozone levels can aggravate lung diseases like asthma, emphysema and COPD. When the air quality is unhealthy, people with these conditions may experience symptoms like difficulty breathing deeply, shortness of breath, throat soreness, wheezing, coughing or unusual fatigue. If you are experiencing any of these symptoms, use your inhalers as directed and contact your health care provider.

Take precautions

Everyone should take precautions when the air quality is unhealthy.

• Take it easy and listen to your body

• Limit, change or postpone your physical activity

• If possible, stay away from local sources of air pollution like busy roads and wood fires

• If you have asthma or other breathing conditions like COPD, make sure you have your relief/rescue inhaler with you

People with asthma should review and follow guidance in their written asthma action plan. Make an appointment to see your health provider if you don’t have an asthma action plan.

Pollution reduction tips

Ozone is produced on hot, sunny days by a chemical reaction between volatile organic compounds and oxides of nitrogen.

• Reduce vehicle trips and fill up the gas tank at dawn or dusk.

• Encourage use of public transport or carpool, when possible.

• Postpone use of gasoline-powered lawn and garden equipment on air alert days. Use battery or manual equipment instead.

• Avoid backyard fires.