Extras
When smog issue plagued their city in the mid 20th century, Angelenos got creative.
The major breakthrough in understanding L.A.'s deadly smog came from a surprising place.
How has L.A.'s history of smog shown up on the big screen?
Watch a preview of Clearing the Air: The War on Smog.
We were told to "shake it like a Polaroid picture". But what if we got it wrong?
Thousands of Superfund sites have been identified across the United States.
22,000 tons of toxic waste in your own backyard