PEASOUPFOG
Pea soup fog
Pea soup, or a pea souper, also known as a black fog or killer fog, is a very thick and often yellowish, greenish, or blackish smog, caused by air pollution that contains soot particulates and the poisonous gas sulfur dioxide. These very thick smogs occur in cities and are derived from the smoke given off by the burning of soft coal for home heating and in industrial processes. Smog of this intensity is often lethal to vulnerable people such as the elderly, the very young and those with respiratory problems.The above text is a snippet from Wikipedia: Pea soup fog
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