HealthDay: In the state of California, failure to meet federal and state standards for air pollution was responsible for nearly $200 million in hospital medical expenses over a three-year period, a new study reports. The Rand Corp., which released the study March 2, estimates that excessive levels of air pollution — including ozone and fine particles in the air — caused nearly 30,000 emergency hospital visits and admissions over the time period from 2005 to 2007 in California. Government …