Illinois U.S. Sen. Dick Durbin is calling for an investigation into the pollution levels that could affect Metra passengers. That follows a Chicago Tribune story that shows diesel soot levels on some trains are abnormally high.

Senator Durbin, a Democrat, said he wants a study of Metra’s pollution levels by government agencies, including the Environmental Protection Agency and the Occupational Safety and Health Administration. In particular, he wants the agencies to look at the safety levels of what’s called diesel soot; particulates from diesel engines.

“Not only does it aggravate bronchial situations and pulmonary disease and asthma, but it really has been traced to cancer,” Durbin said. “It’s a serious issue.”

Durbin said he’d like to see newer engines in Metra trains, but that’s expensive. “Four-million dollars for a new engine, $2 million to rehab an old engine. So, they’re looking at the reality of the bottom line,” Durbin said.

Durbin said in the meantime, Metra recently received grant money that would help it keep trains from having to sit for hours with their engines on while waiting to leave Ogilvie Transportation Center.