Breathing air in polluted metropolitan areas such as Los Angeles or Riverside can reduce your life expectancy by 2 to 3 years.

Transportation sources such as cars, trucks, buses, ships and trains account for 90% of the cancer risk associated with air pollution.

Diesel exhaust from trucks, ships, trains and buses has been declared to contain over 40 substances listed as hazardous air pollutants by the U.S. EPA.

When you drive in bumper-to-bumper traffic, pollutants outside can seep into your car, making the air you breathe inside your car up to 10 times more polluted than typical city air.

Every day that a ship sits at dock unloading its cargo, it releases an entire ton of smog-forming and toxic pollutants.

If you live, work or go to school near high-traffic roads, seaports or railyards, you face a greater risk of cancer or decreased lung function, as these places contain more concentrated levels of air pollution.

For your child, toxic air pollution is an even bigger problem, in part because children breathe much more quickly than adults.

Asthma is a leading cause of school absenteeism, according to the California Department of Education.

Even if you don't smoke cigarettes, your lungs or heart may be similarly damaged simply from exposure to ozone and particulate matter.

Health impacts from diesel pollution exposure, such as premature death, heart disease, asthma and bronchitis, cost some $22 billion statewide in 2004, not including impacts such as lost work and school days.