The Oregon Department of Environmental Quality has issued an air quality advisory for Central Oregon counties affected by wildfire smoke.

The department warns that smoke could be at unhealthy levels through noon Friday. DEQ air quality monitors in Central Oregon Thursday morning showed pollution at unhealthy levels for sensitive groups, which includes people with heart and lung disease, older adults and children.

While no major fires are burning in Central Oregon, large wildfires in Southern Oregon and Northern California are contributing to smoke in the region.

Pollutants in smoke can cause burning eyes, runny nose, and can aggravate heart and lung diseases and other serious health problems, according to the DEQ.