1943: In the middle of World War II, Los Angeles residents believe the Japanese are attacking them with chemical warfare. A thick fog that makes people’s eyes sting and their noses run has taken hold of the city. Visibility is cut down to three city blocks.
As residents would later find out, the fog was not from an outside attacker, but from their own vehicles and factories. Massive wartime immigration to a city built for cars had made L.A. the largest car market the industry had ever seen. But the influx of cars and industry, combined with a geography that traps fumes like a big bowl, had caught up with Angelenos.
“People in Los Angeles were very proud of their air,” said Chip Jacobs, one of the authors of Smogtown: The Lung-Burning History of Smog in Los Angeles. “They said that L.A. was the land of pure air, and that moving there could cure tuberculosis and alcoholism. They thought there had to be one simple answer.”
The day after the first big smog, city officials pointed to the Southern California Gas Company’s Aliso Street Plant as the source of the thick cloud. The facility manufactured an ingredient in synthetic rubber called butadiene.
Public pressure temporarily shut down the Aliso Street Plant, but the smog episodes continued to get even worse. Undeterred, Los Angeles Mayor Fetcher Bowron announced in August that there would be “an entire elimination” of the problem within four months.