Tests Link Cancer To Snarled Freeway Air
 In as little as three months, the brains of  laboratory rats begin to change after being  exposed to the air around congested Southern  California freeways. The evidence we are clearly  seeing is the molecular cascade that can lead to  the development of cancer, said Dr. Keith L.  Black, chairman of the department of  neurosurgery at Cedars-Sinai Medical Center in  Los Angeles.