The Gazette-Times

Due to rising pollution levels related to stagnant weather conditions, the state Department of Environmental Quality issued an "air pollution advisory" Friday for much of the Willamette Valley, the Greater Portland-Vancouver area, and the Medford/Grants Pass area.

The National Weather Service in Oregon issued an "air stagnation advisory" for the region. Stagnant conditions are expected to persist through the weekend and into Monday. The exceptions are areas near the Columbia River Gorge, where east winds should keep pollution levels down, and the Eugene-Springfield area.

According to the weather service, much of the area is experiencing light winds and dry, cold air in combination with low overnight temperatures. These weather conditions create inversions that keep fine particles from wood smoke and vehicle exhaust trapped at ground level, particularly during the evening and early morning hours. These microscopic particles are inhaled deeply into lungs and can damage delicate lung tissues.

Higher-than-usual pollution levels may cause health problems for sensitive individuals. According to the Environmental Protection Agency, people with heart or lung disease, older adults and children are at greatest risk from particulate pollution and should consider restricting their outdoor activities beginning early in the evening and through early morning until the weather changes.

DEQ is currently seeing highest levels of pollution in the evening, when people are using wood stoves. These higher levels typically persist into the early morning hours. If burning wood is your only source of heat, burn hot fires using dry wood to lessen pollution.

To see current pollution levels, see the DEQ's Web site at www.deq.state.or.us/aqi/index.aspx.