How polluted is the air in London? Well, it is so dirty than it is more polluted than the air in Beijing, in terms of nitrogen dioxide concentration. In fact, levels of the nitrogen dioxide in London’s center monitoring station – in Marylebone Road -- are the highest in Europe.
Where did that come from? The city has initiated several measures aimed at reducing carbon dioxide emissions, including toll for entering central London, a bike-hire program and growing public-transport network.
The European Union has traditionally urged people change into diesel vehicles since such units let out less carbon dioxide. But diesel engines have a dirty secret – they emit contaminants like the very harmful nitrogen dioxide.
Simon Birkett, founder of Clean Air in London nonprofit group, remarked to Bloomberg that governments knew over a decade ago that diesel emits harmful pollutants, but chose to turn a blind eye and focused on just reducing carbon dioxide emissions.
He said that this has led to a “public-health catastrophe." Diesel also has another secret – its combustion leads to emission of tiny particles called PM2.5s, which according to government agency Public Health England, probably lead to deaths of 3,389 people in London in 2010.
Jeremy Langrish, a clinical lecturer in cardiology at the University of Edinburgh, remarked since nitrogen dioxide and PM2.5s are both results of diesel combustions, it has become hard to identify deaths attributable only to NO2.
Langrish noted that exposure to air pollution is associated with hikes in deaths from cardiovascular disease like heart attacks and strokes. He added that exposure to air pollution is also associated with respiratory issued like asthma.
According to The World Health Organization, nitrogen dioxide can inflame the airways and worsen bronchitis in children. Aside from London, the cities of Paris, Rome, Athens, Madrid, Brussels and Berlin also had locations that have excessive NO2 concentrations. [source: automotive news - sub. required]