Donora Death Fog: The Crisis that Led to Modern Air Pollution Laws

Overview

The Donora Death Fog, while not widely known, was a pivotal event in 1948 that contributed to the initiation of air quality regulations in the U.S.
Occurred in Donora, Pennsylvania, causing 20 deaths and hospitalizing half the town due to trapped toxic gases from a weather phenomenon known as an atmospheric inversion.

Date: October 26, 1948
Location: Donora, PA, home to U.S. Steel Corporation’s Donora Zinc Works and American Steel and Wire.
Phenomenon: Atmospheric inversion leading to thick smog.
The fog intensified by October 29, reducing visibility to the extent that even during a local football game, players were not visible.
U.S. Steel plants ceased operations on October 30, and the fog lifted the following day.

Anticyclone: A high-pressure system covering large areas, causing air to move downward and outward in a clockwise motion. This naturally occurring weather event combined with industrial pollution led to the disaster.
Geography: Donora is located in the Monongahela River Valley, which contributed to the weather inversion.
Pollution Trapped: Toxic particulates like zinc, cadmium, and lead were compounded by hydrofluoric acid, sulfur dioxide, and carbon monoxide.
Impact: Acute fluorine poisoning was identified in victims, and all crops perished, particularly corn due to its sensitivity to fluorine.

Not the only recorded deadly temperature inversion: similar events in Belgium (1930), Mexico (1950), and London (1952).
Air Pollution Laws:
- California passed its first state pollution law in 1947.
- The Federal Air Pollution Control Act was enacted in 1955.
- The Clean Air Act was established in 1963, authorizing government control over pollution.
Environmental Protection Agency (EPA):
- Created by an Executive Order from President Nixon in 1970.
- Enforces United States air pollution laws, including those under the Clean Air Act Amendments of 1970.

The Donora Smog Museum emphasizes the impact of the event with the tagline "Clean Air Started Here."
The event was instrumental in raising awareness of air pollution hazards, leading to significant political and regulatory actions.