Polluted London sets its sights on cars

London : Gone are the days of London's "pea souper" smogs, but like many European cities, the British capital is once again being choked by pollution -- and has road traffic firmly in its sights.

In 1952, the Great Smog suffocated London for five days, bringing the city to a standstill as soot-filled clouds descended onto the streets and into people's lungs, leaving more than 12,000 dead.

The crisis prompted a clampdown on the use of coal in the city --  but decades on, pollution is still causing more than 9,000 premature deaths per year.

This time, the key culprit is nitrogen dioxide (NO2), produced by cars and trucks -- and particularly diesel engines, which emit three times more NO2 than petrol vehicles.

"Industry... is part of the problem, but the focus, the problem areas are next to roads," Gary Fuller, a senior lecturer in air quality measurement at King's College London, told AFP.

London Mayor Sadiq Khan is on a personal mission to deal with the "lethal" air in the city, after blaming pollution for his adult-onset asthma.

This week he announced plans for new charges for diesel cars and older petrol vehicles, which could see drivers pay £24 (28 euros, $30) a day to enter central London by 2019.

But the issue is not just confined to the city centre, or indeed to the capital itself.

"The NO2 limit value is exceeded in many major cities up and down the country," Fuller said.