When did Los Angeles First Experience Smog?

Los Angeles experienced its first smog in 1943. Residents believed that it was part of a Japanese chemical warfare attack, when in fact it was because of the rapidly increasing automobile traffic. Prior to 1943, Los Angeles was known for its pure air, and even had many recovery wards for tuberculosis patients.

More facts about smog:

• The word smog is actually a portmanteau of the words fog and smoke. The word was first used in London in the early 1900s.


• Smog tends to take on a different color according to what causes it. Gray smog is usually caused by industrial byproducts like ash and sulfur, while brown smog is caused by car emissions.


• The American Lung Association estimates that over half of Americans live in counties with dangerously high levels of smog.