Wildfire smoke is driving terrible air quality in major cities, but relief is coming

Thick, choking plumes of smoke from wildfires in Canada are pouring into major cities across the Midwest, Northeast and mid-Atlantic, bringing dangerous air quality to more than 100 million people. More than 100 million people in 18 states and the District of Columbia are under air quality alerts. "Very unhealthy" and "hazardous" air quality stretches from northeast Minnesota to southeast Virginia. Milwaukee, Chicago, and Detroit had some of the worst air quality in the country Friday morning, but dangerous levels of pollution stretched into southern Ohio and West Virginia. "Chicago is currently experiencing its worst air quality in recorded history," the mayor's office said in a social media post Thursday evening. "Please stay indoors, and if you must go outdoors, use a well-fitted N95 or KN95 mask for your safety." The Detroit Health Department is offering free masks to residents on Friday and encouraging everyone to stay inside. In Philadelphia, "everyone is likely to experience health effects from being exposed" to smoke in the air Friday, officials warned in a media release. Worst current air quality: Toledo, Ohio, Hazardous, 471. Grand Rapids, Michigan, Hazardous, 428. Columbus, Ohio, Hazardous, 413. Duluth, Minnesota, Hazardous, 351. In Canada, 3,500 fires have burned more than 6 million acres this summer, with a dozen blazes flaring up in Ontario in recent weeks, filling the skies with smoke drifting south, like it did in an extreme way in 2023. Canadian wildfire activity this year is nowhere near the hyperactivity of 2023 but the combination of wildfires in Ontario and a heat dome in the central US spells smoky trouble for millions. Climate change was found to be responsible for the majority of the increase of surface wildfire smoke. Wildfire smoke contains dangerous, tiny pollutants called PM2.5 that can travel deep into the lungs or enter the bloodstream when inhaled.