HELENA, Mont. (AP) — Smoke pollution from wildfires burning across the West has again made the air unhealthy to breathe throughout much of western Montana, state officials said Thursday.
Wildfire smoke contains microscopic particles that can irritate the lungs and increase a person's susceptibility to infections including COVID-19, officials said.
Air quality reached unhealthy levels on Thursday across a 20-county area that included the cities of Missoula, Great Falls, Helena, Butte and Bozeman, the state Department of Environmental Quality said.
The poor air quality was expected to linger into Friday. It comes at the tail end of a summer that has seen frequent air quality warnings across large areas of the U.S.
The smoke is from fires burning in Montana and across the western U.S., a region parched by prolonged drought.