On 10 December 1952 life in London was starting to return to normal; trains and buses were running again and theatres and cinemas could reopen. The fog that had shrouded the capital between the 4th and 9th had dispersed, leaving around 4,500 deaths in its wake and another 15,000 Londoners ill and off work. High death rates continued until the following February: they were initially attributed to flu, but modern re-analysis suggests that 7,000 more people died from smog effects in subsequent months. This was neither the first nor the last smog to kill people. Warning signs included two smogs in industrial towns: in 1930 in the Meuse Valley, Belgium where 60 people died and, in 1948, Donora, Pennsylvania in the US where a two-day smog killed 20 people and left 6,000 ill – over 40% of the town’s population.
The 1956 Clean Air Act with its smokeless zones brought about great improvements in London’s air but not before smogs in 1956, 1957 and 1962 claimed around 1,500 more lives. With the widespread availability of natural gas, and closure of much of London’s industry and riverside power stations, the air in the capital is now very different. But the hazard from solid fuel burning has been replaced by new urban pollutants, mainly from diesel traffic. Today, London’s air pollution represents a health burden of around 4,300 deaths per year, a similar figure to those killed in the first days of the 1952 smog.
via Pollutionwatch: Clean Air Act in 1956 cleared London smogs | Environment | The Guardian.