The Chicago region’s air quality is one of the worst in the country. Health advocates say diesel-burning trucks and equipment are a major cause.

The transportation industry contributes billions of dollars to our region’s economy, but there’s a downside. Each semi-truck and diesel-burning train spews soot into the air; much more than an average car.

Health experts say the pollution causes thousands of cases of asthma each year. New research suggests kids are particularly susceptible if they live near busy roads.

That worries Brian Urbaszewski of the American Lung Association. He says cleaner semis will be on the market later this year.

“The problem is that these devices are only going to be required on new vehicles off the factory floor, and we literally have hundreds of thousands of these vehicles out there that are going to pollute for years to come,” he says.

Local governments are trying to improve air quality. For example, Illinois required contractors to use cleaner diesel equipment for the Dan Ryan construction project. The City of Chicago made similar requirements for contractors working on O’Hare expansion.