Wildfire smoke continues to cause unhealthy air in Oregon

Jan 20, 2024

Wildfire smoke continues to cause unhealthy air quality across Oregon, a new study from the state Department of Environmental Quality shows.

Last year's wildfire season was less intense than those of 2020 and 2021, the study reported. There also was less smoke in 2022 compared with other recent years.

There still were long-lasting fires, however, that created unhealthy air quality in communities across the state.

Last year, most of the smoke impacts were in central and southern Oregon, according to the report.

Oakridge, southeast of Eugene, had more days with unhealthy air quality than anywhere else in the state. At 37 days, it's also the most ever experienced by the city.

The largest fire in Central Oregon last year, the Cedar Creek Fire, burned just outside Oakridge, starting on Aug. 1 and burning into October. It rapidly increased in size in September when strong easterly winds and unusually warm weather impacted the state.

Willamette Valley cities experienced more days with poor air quality last year than in 2021, though fewer than during the catastrophic wildfires of 2020.

Eugene had seven days with unhealthy air quality last year, up from three in 2021. Salem had three, up from zero in 2021. Albany had two, up from zero in 2021. Portland had three, up from zero in 2021.

The yearly report tracks wildfire-related air quality trends in 24 Oregon communities, using data from the Air Quality Index.

The index measures levels of fine particulate matter, or PM 2.5, the primary pollutant in wildfire smoke. It categorizes air quality, from best to worst, as good, moderate, unhealthy for sensitive groups, unhealthy, very unhealthy and hazardous.

The report calls the number of days in the in the four worst groups "unhealthy air quality days."

The report shows that since 2012, air quality has been worsening, with more frequent days categorized as unhealthy or worse.

The state's wildfire season historically started in late July and ended in early September. Now, fires have been starting in mid-July and lasting until early October.

Fires also are larger, according to the National Interagency Fire Center.

"If these trends continue, Oregon should expect to see an increasing number of days with (unhealthy air quality) during the summer, and not just in Southern Oregon where it is more common," the report reads. "This will include areas which have historically not seen significant smoke impacts, such as the north coast, the Willamette Valley and the Portland Metro area."

Wildfire smoke contains a wide variety of pollutants, including particulate matter (PM2.5 and PM10), black carbon, nitrogen dioxide, carbon monoxide, volatile organic compounds, polycyclic aromatic hydrocarbons and metals.

According to the Oregon Health Authority, PM2.5, which are the smallest particles, may represent the greatest health concern because the particles can be inhaled deeply into the lungs and may even reach the bloodstream.

OHA offers recommendations for staying safe during smoke events:

Tracy Loew covers the environment at the Statesman Journal. Send comments, questions and tips:[email protected] or 503-399-6779. Follow her on Twitter at@Tracy_Loew