Those who live in the Central Valley know our air is bad, but now researchers are connecting the dots with what's making our air so unhealthy.
Scientists at U.C. Davis. have been studying air quality samples taken along Shaw Avenue in Fresno, from 2008 and 2009.
They have been able to isolate key sources of air pollution, measuring everything from tail pipe emissions to smoke from barbeques.
Dr. David Lighthall, health science adviser for the San Joaquin Valley Air Pollution Control District said, "In a concentrated source environment, like Shaw Avenue, in a city like Fresno, we do have a high concentration of primary emissions. So the good news is, the sources and the health risks that were identified in this study, are exactly the kinds of things that the air district here is focusing on."
The smaller particulate matter is considered to be the most harmful and is linked to higher rates of heart and lung disease.
Everything from gross polluting vehicles to commercial barbeque restaurants are being looked at for more emissions control.