LeftieBiker wrote:I grew up (and still live) across the Hudson River from an old paper mill town. One square mile, and something like three paper mills. I'd walk over the bridge after school, and the river would be filled with floating globs of yellow foam, while the air smelled of rotten eggs. I've never been to LA, but I can imagine it.
Industrial pollution long predates LA's primarily car-induced 'photochemical' smog, as does the word 'smog' itself, usually claimed to have been invented in 1905 (possibly in 1893 or earlier) as a contraction for (coal) smoke + fog. As far as U.S. toxic smog incidents, this one may be the worst for acute effects not caused by an accident:
1948 Donora smog
The 1948 Donora smog was a historic air inversion that resulted in a wall of smog that killed 20 people and caused respiratory problems for 6,000 people of the 14,000 population of Donora, Pennsylvania, a mill town on the Monongahela River 24 miles (39 km) southeast of Pittsburgh. The event is commemorated by the Donora Smog Museum.
Sixty years later, the incident was described by The New York Times as "one of the worst air pollution disasters in the nation's history". Even 10 years after the incident, mortality rates in Donora were significantly higher than those in other communities nearby. . . .
As for the most acutely toxic coal smog event, that would probably be this from 1952:
Great Smog of London
The Great Smog of London, or Great Smog of 1952, was a severe air-pollution event that affected the British capital of London in early December 1952. A period of cold weather, combined with an anticyclone and windless conditions, collected airborne pollutants—mostly arising from the use of coal—to form a thick layer of smog over the city. It lasted from Friday, 5 December, to Tuesday, 9 December 1952, and then dispersed quickly when the weather changed.
It caused major disruption by reducing visibility and even penetrating indoor areas, far more severe than previous smog events experienced in the past, called "pea-soupers". Government medical reports in the following weeks, however, estimated that up until 8 December, 4,000 people had died as a direct result of the smog and 100,000 more were made ill by the smog's effects on the human respiratory tract. More recent research suggests that the total number of fatalities may have been considerably greater, one paper suggested about 6,000 more died in the following months as a result of the event.
London had suffered since the 13th century from poor air quality, which worsened in the 1600s, but the Great Smog is known to be the worst air-pollution event in the history of the United Kingdom, and the most significant in terms of its effect on environmental research, government regulation, and public awareness of the relationship between air quality and health. It led to several changes in practices and regulations, including the Clean Air Act 1956. . . .
China's endemic smog is a factor in shortening the lives of far more people on an annual basis, and possibly they may have had more acute deaths in some events than the above, but they weren't reported.