Killer Smog

October 26, 1948 - Today was the first day of a deadly week for Donora, Pennsylvania. A suffocating smog rolled over the town of 14,000 and sickened half the population. 20 people and hundreds of animals would die within 5 days. The New York Times called it one of the worst air pollution disasters in American history.

Donora was a mill town and residents had grown accustomed to the sulfur dioxide emissions from two factories, the Donora Zinc Works and the American Steel & Wire Plant. What turned the smog deadly was an unusually warm mass of air that settled over the town and trapped the killer fumes in a valley.

At the worst point in the week, citizens of Donora had to stew inside a thick cloud of acrid yellow smog that included toxic levels of sulfuric acid, nitrogen dioxide and fluorine. The density of the poisonous air made it almost impossible to drive, so emergency vehicles had to creep along the sides of roads, hugging the curb. Drivers actually craned their heads out the car windows since their windshields were caked in sticky muck.

A team of heroic doctors fanned out across the town delivering life-saving oxygen to their sickest patients. Relief finally came on Halloween when it rained. In the aftermath, investigators quickly zeroed in on the town's zinc plant as the biggest contributor to the disaster. Its emissions were so toxic that all the vegetation within a half-mile radius of the plant died.