In the middle of World War II, Los Angeles residents believe the Japanese are attacking them with chemical weapons. A thick fog that makes people’s eyes sting and their noses run takes 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 LA the largest car market the industry had ever seen. But the influx of cars and factories—combined with the region’s bowl-like topography, which trapped fumes—created trouble for Angelenos.
After the first big smog, public pressure temporarily shut down a Southern California Gas Company plant, but the smog episodes continued to get worse. The mayor announced the problem would be eliminated in four months. Ha! (Cough!)
The search for the culprit of the “gas attacks” wasn’t found until the early 1950s.Caltech chemist Arie Haagen-Smit was the first to recognize ozone as smog’s primary source. Ozone is created when partially unburned exhaust from automobiles and the hydrocarbons from oil refineries are hit by sunlight. Haagen-Smit also demonstrated that ozone was the cause of the bleach smell LA residents were reporting, as well as the source of their eye irritation and respiratory problems.
But LA built more and more freeways, and new industries came into town. The smog became commonplace, with dangerous levels as often as two hundred days a year. People got used to it. (Wheeze!)
It would take another twenty years for California to finally enact decisive standards to limit smog pollution from vehicles. The smog laws were ultimately mirrored across the country.—JM