Back in December 1952, the city of London was enveloped by a dense smoke-filled fog that lingered for four days and brought the city to a standstill. Cars and buses couldn't drive down the street, and train service had to be halted because visibility was so poor.
The foul air even crept indoors, and an opera had to be halted in mid-performance because was impossible for the audience to see the stage. At a livestock show, cattle keeled over from inhaling the tainted air. Hospitals were filled with patients in respiratory distress--more than 4,000 of whom eventually died as a result, by one estimate.
The horrifying environmental disaster, caused by the combination of a high-pressure front and light winds that trapped fumes over the city, led the British government to phase out coal furnaces, and in the years since, the city has built 80 monitoring stations in an effort to be more vigilant about air quality.
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Even so, the health effects of the Great Smog still persist, according to a newly published study in the American Thoracic Society's American Journal of Respiratory and Critical Care Medicine.
In the study, researchers from Columbia University's Mailman School of Public Health, the University of California, San Diego and University of Massachusetts studied how London's Great Smog affected early childhood health and the long-term health consequences.
The scientists found that children exposed to the Great Smog in their first year of life were nearly 20 percent more likely to develop childhood asthma than those who weren't, and nearly 10 percent more likely to have asthma as adults.
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