Killer fog may sound like a hokey horror novel, but for those who survived the environmental disaster in London, it was no laughing matter. Actually, many people had problems simply breathing normally. Although it dissipated in four days, the killer smog of 1952 claimed at least 4,000 lives, according to some estimates. Others place the possible death toll at around 12,000.
London has a history not only of fog but also of thick, nasty smog, and 1952 was not the first time smog took over the city. There are reports of notable smog attacks in 1813, 1873, 1948 and other years. The smog tended to be worse in the winter months, when Londoners would burn more coal to keep warm. Factories that emitted poisonous smoke didn't help either.
Carbon dioxide, hydrochloric acid, fluorine compounds and sulphuric acid clung to water particles in the air to form the deadly fog. Problems were further compounded by the anticyclone hanging over London - this is a system of rotating winds that pushed air downwards and trapped the smoke over the city, preventing it from dissipating.
The infamous smog of 1952 began on December 5. Although the day started out clear, people walking around outside quickly realized there was a serious problem. Visibility was rapidly reduced and drivers could barely see ahead of their cars. Some Londoners reported having to abandon their cars and that when they got out to walk instead, they could not even see their feet.
The killer fog suffocated some Londoners to death. Oxygen levels were low and people had to gasp for breath. Other unfortunate souls died of cardiac arrhythmia, possibly due to the high ozone levels.
On December 9, Londoners finally began to breathe a little easier and see more than a foot in front of their face. The smog lifted and lawmakers tried for environmental reforms. The 1952 killer fog directly impacted the passage of the Clean Air Act of 1956, which encouraged the use of smokeless fuels and placed factories under tighter restrictions. Unfortunately, reform was not quick enough for the approximately 750 Londoners who died in a lesser smog in 1962.