The Donora Killer Smog which came in 1948 was primarily as a result of emissions from the steel mill .
The Donora Killer Smog happened in the town of Donora, Pennsylvania in the year 1948 and led to the death of 20 people while cauing injusries to more than 6,000 people.
The reason for the smog was because of the steel mill in the town emitting harmful substances in the air and due to atmospheric conditions at the time, it developed into a killer smog.
Find out more on the SMog at https://brainly.com/question/8911267
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