See the USA in your Chevrolet (if you can)

On this day in 1943, a thick "hellish cloud" reeking of bleach descended on the city of Los Angeles.

Residents flew into a panic, suspecting a Japanese chemical attack. But the real culprit was their cars. It was the first wave of "smog" to hit the City of Angels, though the phenomenon would become a familiar, and dangerous, presence in the decades to come.

https://www.smithsonianmag.com/smart-news/1943-hellish-cloud-was-most-vivid-warning-las-smog-problems-come-180964119/