The Cleveland Department of Public Health’s air quality division and the Northeast Ohio Areawide Coordinating Agency both issued health alerts because of the air. Cleveland called off all outdoor recreation programs for the day, closed its outdoor pools, spray basins and water parks, and canceled trash collection.

The air was so unhealthy that Chris Ronayne, the executive of Cuyahoga County, which includes Cleveland, canceled his annual speech on the state of the county at Jacobs Pavilion at Nautica, an outdoor venue on the banks of the Cuyahoga River.

At the same time, Major League Baseball was pressing ahead with games.

In Pittsburgh, where the Air Quality Index had at one point reached 180, according to AirNow, the Pirates issued a statement saying that they intended to play their game on Wednesday against the San Diego Padres. In Chicago, the Cubs had yet to comment by midafternoon on Wednesday evening’s scheduled game against the Philadelphia Phillies.

Health officials said they remained concerned about the continuing effects of the wildfires on vulnerable populations, including older people, children, people with health conditions and the homeless.

Chad Audi, the president of Detroit Rescue Mission Ministries, which provides services for the homeless, said he was receiving more calls on Wednesday about people with asthma and had referred two people to a hospital.

“We bend the rules a little bit because they’re supposed to be leaving the facility after they have breakfast and come back during dinner time,” he said of the shelter he runs. “As long as we have bad air quality, we’re allowing people to stay. ”

Reporting was contributed by Scott Atkinson, Delger Erdenesanaa, Lola Fadulu, Emma Fitzsimmons, Benjamin Hoffman, Ryan Patrick Hooper, Ida Lieszkovszky, Anushka Patil, Campbell Robertson, Michael D. Shear and Raymond Zhong.