ST. PAUL — If you have noticed the haze outdoors lately, there may be an explanation.

The Minnesota Pollution Control Agency (MPCA) listed most state air quality at the moderate level Thursday.

The trend will continue the next several days, with weak surface winds with a predominantly southerly component, according to the MPCA.

“While this will bring some warmer air than we have had the past couple days, the weak winds are allowing for pooling of particulate matter,” read the MPCA air quality detailed forecast.

Particle pollution, also called particulate matter is made up of tiny pieces of solids or liquids in the air, according to the Centers For Disease Control and Prevention (CDC).

Particles may include dust, dirt, soot, smoke and drops of liquid. Primary particle sources include wood stoves. Secondary particle sources include motor vehicles, according to the CDC.

The MPCA listed Minnesota air pollution particle levels Thursday morning at 85 in the Twin Cities, 78 in Detroit Lakes, 77 in St. Cloud, Marshall 68, Rochester 67, West Duluth 63, Brainerd 54. The particle level at Ely was listed at 3 Thursday.

Moderate air quality particle levels range from 51 to 100. Good air quality particle levels are under 50. Unhealthy levels for sensitive groups at 101-150, unhealthy 151-200 and very unhealthy 201-300.

Moderate air quality is acceptable but there may be some risk for some people, particularly those who are unusually sensitive to air pollution, according to airnow.gov.

Particle pollution has been linked to eye, lung, and throat irritation, breathing trouble, lung cancer and problems with babies at birth, such as low birth weight, according to the CDC.

In addition, particle pollution may make asthma and heart disease symptoms worse.

Ways to deal with high particle pollution levels include avoiding busy roads and highways due to motor vehicle emissions.

For more information, visit cdc.gov and pca.state.mn.us/air/current-air-quality

Fritz Busch can be emailed at fbusch@nujournal.com.