A recent investigation by The Chicago Tribune has found that plenty of vehicles around the city are being allowed to idle on city streets, even though a tough law was passed over four years ago to severely limit such behavior. According to the investigation, Chicago police have not written a single ticket for violation of the anti-idling law. Diesel exhaust is a well-known trigger of asthma attacks, and has been labeled as one of the single most dangerous types of air pollution by the U.S. Environmental Protection Agency. Studies have shown that miniscule particles of soot in diesel exhaust often become lodged in the lungs and penetrate into the bloodstream, even in areas of low concentration.
As Michael Hawthorne of The Tribune reports, "To leave diesel-powered vehicles idling for more than three minutes is illegal in Chicago, yet the Tribune observed dozens of violations in the last three months. The fumes are more than an acrid nuisance; testing by the newspaper found the amount of lung- and heart-damaging soot in the air next to idling buses soared up to 30 times higher than normal street levels."