摘要

<正>London may be known for its drizzly weather,but in 1952 the city’s quintessential1fog cover turned deadly,and no one knew why—until now.For five days in December 1952,a fog that contained pollutants enveloped all of London.By the time the dense fog cover lifted,more than 150,000 people had been hospitalized and at least 4,000 people had died.Researchers now estimate that the total