The area's industries and individual residents will be asked to voluntarily reduce emissions that cause ozone pollution. The area shown on the map has a severe ozone-pollution problem. Although ozone cannot be seen or tasted it can irritate lungs and make breathing difficult. The urban haze that we call smog contains pollutants that react to form ozone. Most of the pollutants that form ozone come from cars.
Large factories account for another portion of the emissions.
Small businesses such as printing plants, service stations, and auto body shops, and people using lawnmowers, paints, and cleaning solvents account for another portion of the emissions. Ozone pollution is of particular concern to the more than 500,000 people with asthma and other respiratory problems in the Lake Michigan area, because when it is breathed into the lungs, ozone reacts with lung tissue. It can harm breathing passages, making it more difficult for the lungs to work. It also can cause eye and throat irritation and cause a greater susceptibility to infection. There is an association between ozone levels in the outdoor air and increased hospital admissions for respiratory causes, such as asthma.