Rep. Calvin Callahan joined lawmakers from Iowa, Minnesota and North Dakota in filing a formal complaint against Canada over wildfire smoke.

Air quality has taken a serious hit across the United States as a twofold blow of wildfires in the West and in Canada have sent smoke pouring across large sections of the country — a problem that’s set to linger for days.

As Canada grapples with one of its worst wildfire seasons on record, smoke from the blazes have prompted air quality alerts across the U.S.

Breathing in polluted air for extended periods of time can pose a serious health risk for people, especially for vulnerable populations.