The UK capital’s controversial congestion charge is responsible for higher levels of the dangerous nitrogen dioxide, says a new research report from a leading science and technology university.
The ULEZ charge, which was first introduced in 2003, has been studied as to its effectiveness at reducing pollutant levels by the Norweigian University of Science and Technology (NTNU), but the research has found that a 20 per cent increase in buses and black cab taxis has increased NO2 levels.
The study’s lead, Professor Green from NTNU said that although levels of carbon monoxide and other particulate matter dropped after the congestion charge was introduced, but the NO2 levels only fell minimally.
Professor Green said that any drops in emissions has to be factored against the fact that newer cars were pumping out less pollution as the decade wore on.
“For instance CO emissions were on average falling in all urban areas in the UK for a variety of reasons including the vehicle fleet becoming 'cleaner',” Green told The Daily Mail.
“This means if you just compare London before and after the change it looks like the congestion charge reduced CO. But you would find this if you picked any two random points in the 2000s.
“To get people onto public transport, the buses and black cabs were exempt from the charge,' said Professor Green.
“Bus departures and routes were expanded after introducing the charge in the city centre. Bus and taxi traffic increased by more than 20 per cent.'
“The problem was that all the buses and London taxis ran on diesel.”
London has exceeded national air pollution levels since 2015 and scientific evidence shows that just 30 minutes of exposure to NO2 can lead to adverse respiratory effects.
Despite this a spokesman for the London mayor Sadiq Khan said that the city has stopped licensing diesel black cabs and has made the fleet of buses greener.
“Fifty thousand people are estimated to die prematurely in the UK every year due to air pollution,' said Professor Green.
“Before the coronavirus, exhaust was the fastest growing cause of death globally.
“In fact, researchers in Germany have found that exposure to exhaust leads to a sharp increase in coronavirus mortality.”