Killer smog, continuing over London for the next 4 days. 50 years ago today, London was beset by its worst ever atmospheric pollution. An anticyclone settled over London, the wind dropped, the air grew damp and a thick fog began to form. In many parts of the capital it became impossible for pedestrians to find their way at night, and in the Isle of Dogs the visibility was at times nil. High concentrations of smoke and sulphur dioxide in the air caused many Londoners to suffer respiratory or cardiac problems, and perhaps as many as 12000 deaths eventually followed. It was reported that a number of cattle at Smithfield Market died of asphyxiation, and a performance at the Sadler's Wells Theatre had to be suspended when fog in the auditorium made conditions intolerable. In response to the Great London Smog, the Government passed its first Clean Air Act in 1956 which regulated what could be burned in houses and created smoke-free zones.
50 years later, in spite of an unjustified international reputation, London is now only rarely beset by fog. There may still be pollution in the air, but it's of a very different kind. Modern pollutants from vehicle exhausts include carbon monoxide, nitrogen dioxide, ozone, benzines and aldehydes. They are less visible than the pollutants of yesteryear but are equally toxic, causing eye irritation, asthma and bronchial complaints. Perhaps we'd all do better to campaign against existing air pollution rather than worry about the vague threat of a terrorist gas attack on the tube.