Did You Know? ~ Donora, Pennsylvania, Killer Smog

On October 27, 1948, a deadly smog began amassing in the working town of Donora, Pennsylvania. By the following day, residents suffered signs of respiratory distress, which was attributed to asthma. People attending a football game couldn’t see the players on the field. Driving home was like driving in dense fog. The smog kept growing, and over the next week, twenty people died. The smog continued until rain fell on October 31. Afterward, fifty more people died and hundreds suffered health problems for the rest of their lives. Even ten years after the incident, mortality rates in Donora were higher than those in other nearby communities.

The culprit? An atmospheric inversion layer plus hydrogen fluoride and sulfur dioxide emissions from U.S. Steel's Donora Zinc Works and its American Steel & Wire plant. 

An inversion layer happens when the air near the ground stays cooler than the air above. It doesn’t expand and can’t rise. Whatever is released into the air near the ground stays there. During this deadly week, the factories kept pumping out industrial pollutants, and the people of Donora were slowly poisoned by the cloud that settled over them. Their lungs were burned with sulfur and their red blood cells destroyed by carbon monoxide.

Unfortunately, both U.S. Steel and other companies in Donora conspired with the U.S. Public Health Service to keep the facts from the public. Their part in the incident wasn’t revealed until the 1990s.

On November 1, 2008, the New York Times described the incident as “one of the worst air pollution disasters in the nation’s history.  The Donora Smog Museum was opened on October 20, 2008. It’s located in an old storefront at 595 McKean Avenue near Sixth Street.