Historic Cases
Toxicity Associated with Atmospheric Emissions
Smog, Acids and Metals


Meuse Valley Disaster

The Meuse River Valley west of Liäge, Belgium was the sight of the first extensively documented, and one of the worst, industrial air pollution disasters. Several thousand persons became violently ill, and sixty persons reportedly died from died from atmospheric poisoning between December 3-5, 1930. During those three days, a "soupy" mixture of industrial smoke and fog covered the entire country. It was most concentrated along a length (20 km) of the narrow (1 to 2 km) River Meuse to a height of 60 to 80 m.

Victims, who were primarily elderly, suffered from acute respiratory problems. These included shortness of breath and hoarseness, persistent coughs, production of a frothy phlegm succeeded by a puslike mass, nausea, and vomiting. Deaths were attributed to acute heart failure. While most of the victims were predisposed to injury, because of previously weakened lungs and hearts, other younger and healthier individuals also became seriously ill. Similarly, cattle exhibited the same symptoms, and some died, along with birds and rats in the contaminated area.


Donora Disaster

The greatest air pollution disaster occurred in Donora, Pennsylvania in October, 1948 under remarkably similar conditions to those that occurred eighteen years before in the Meuse Valley. Industrial emissions from several large plants, including zinc smelters, which emitted acids (e.g., sulfuric acid) and from steam locomotives burning high-volatile soft coal were combined with a fog and trapped in the river valley by a high pressure condition. Nearly 6,000 (5, 910) persons (42% of the population) were diagnosed with respiratory and associated problems from the pollution. These included: irritation in their eyes, nose, and throat; pains and constriction in the chest; shortness of breath; severe headaches; nausea and vomiting. The highest illness rates occurred among smokers. Animals (2 dogs, 7 chickens, and 2 rabbits) were also reportedly killed by the air pollution.

This figure illustrates the "agism" of toxicants associated with the Donora disaster. There, as in the Meuse Valley Disaster, the victims were primarily elderly individuals predisposed to the toxic emissions through previous respiratory problems. This individual is being interviewed by a Public Health nurse, who was acquiring information to establish the epidemeology of the incident (photo from the US Public Health Service).



Fossil fuel combustion (fire places and coal burning plants), combined with fog, accounted for even greater disasters in London, England during the 1950's. A total of 4,075 deaths were attributed to atmospheric pollution that occurred in December, 1951. Another 1,000 deaths above the normal rate were subsequently attributed to a toxic fog that only lasted 18 hours in 1956.


Los Angeles

A new form of atmospheric pollution. "smog", was recognized in Los Angeles in the 1940's to 1950's. It is formed by atmospheric reactions with automobile exhaust (smoke) and fog. The highly oxidizing smog in Los Angeles is composed of a mixture of ozone, nitrogen oxides, and peroxidized organic compounds (e.g., peroxycetyl nitrate or PAN). The problem is exasperated by the geography of the Los Angeles basin, which tends to trap the smog during summer periods. The 1960 California Health Department Survey: Air Pollution Effects Reported by California Residents noted that three fourths of the population in metropolitan areas of southern California experienced peculiar burning and annoying irritation of their eyes during peak periods of smog; and there have been numerous acute episodes of smog since 1942.



Another incident occurred in Piscataway, New Jersey in 1971. It was attributed to emissions from several factories, including many chemical plants, and from traffic in the surrounding area. Symptoms included excessive lacrimation (tearing), reddened throats, breathing difficulties, cough, chest pain, abdominal pain, vomiting, and tingling in the extremities.



The common causes of these incidents are primarily attributed to acids formed by industrial emissions (i.e., sulfuric, nitric), as well as carbon monoxide and carbon dioxide from fossil fuel combustion. Other contaminants (e.g., zinc, cadmium, mercury, fluoride,…) released by industrial and fossil fuel combustion are considered to have exacerbated the problem at different locations. One example of this is the history of toxic lead emissions from the Selby smelter in California. These began at the turn of the last century and reappeared intermittently until the middle of this century.


This photo shows the damage caused to vegetation downwind from the emissions from the Selby smelter at the turn of the century (from Holmes et al, 1915). The burns were attributed to sulfuric acid deposited on the leaves. It was derived from atmospheric emissions of sulfur from the smelter.


This photo shows a horse suffering from lead pollution emitted from the Selby smelter at the turn of the century (from Holmes et al., 1915). The flaring nostrils characteristic of "roaring", which is due to the paralysis of the diaphragm. It is caused by lead poisoning through the ingestion of foliage contaminated with lead fallout from the smelter.


Amdur, M.O. 1991. Air Pollutants. In: Casarett and Doull's Toxicology: The Basic Science of Poisons (M.O. Amdur, J. Doull, and C.D. Klassen, eds.), Pergammon Press, New York, NY.

Holmes, J.A., E.C. Franklin, and R.A. Gould. 1915. Report of the Selby Smelter Commission. Bulletin 98, Department of the Interior, Washington, D.C.

Waldbott, G.L. 1973. Health Effects of Environmental Pollutants. The C.V. Mosby Company, Saint Louis, MO.


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