London has some of the highest air pollution rates in the UK and it is the inner city areas that are affected the most.

According to London Mayor, Sadiq Khan, the “most deprived” areas are the places that suffer the most from polluted air and they are exposed to air pollution rates that are 25% higher than average.

So just how bad is the air we breathe in London and what’s causing it?

Well, the air in London is so bad it’s actually illegal, according to the UK and EU Air Quality Limits. According to a study published by Sadiq Khan more than 2 million of us are living with illegally high air pollution rates and 400,000 of that sizeable figure are children. This has dire consequences, especially for children; it stunts their growth and causes a number of illnesses.

The biggest contributor to the filthy air we breathe is roadside transport. It’s roadside diesel vehicles that emit the most Nitrogen Dioxide (NO2) and are the main culprit in the city’s toxic air crisis. The NO2 levels on the roads of inner London have stayed relatively stable since the early 2000s, says the report published by Greenpeace. One of our busiest streets, Oxford Street, leaves shoppers to breathe in air that is 4 times over the legal limit. The pollution caused by diesel cars is so detrimental to our health that the Transport Secretary, Grant Shapps has said the 2040 ban on diesel cars may be moved to five years earlier. Diesel is a huge factor in our toxic air, the Greenpeace report said,

“It will not be possible to address the air pollution crisis in London without tackling this principal source of the problem.”

There isn’t much escaping the dangerously high air pollution levels, especially if you commute into work. The Underground has been deemed the “dirtiest place in the city” with some of the highest levels of polluted air in the capital. According to an investigation led by the Financial Times the pollution levels on the underground are as much as 10 times higher than the guidelines set out by the World Health Organization. For us who commute into work, taking the tube for an hour a day doubles our exposure to PM2.5 particles which is massively detrimental to our health by worming their way into our lungs and causing a number of health problems. TfL claims the air on the underground is safe for us to breathe, according to the Financial Times. Although they have never published their own findings on the air quality on the Underground.

Transport in London is clearly one of our biggest offenders in the toxic air crisis. But what does this mean for real Londoners? I was able to speak to Martin Smith, who has been a resident in Southwark for over 40 years. Southwark has some of the worst air pollution rates in the capital. Martin is also heavily involved in the “anti-poisons movement” and believes strongly in organic living. He has seen firsthand the deterioration in our air quality and has suffered the consequences of it. Martin spoke to us at our Climate Change Live journalism event about what it has been like living in the borough for so long.

Although, on a global scale London’s toxic air doesn’t even compare with the levels in places New Delhi and Kanpur our levels are still lethally high. Causing premature deaths and diseases. We don’t really get to see how bad it is, we just suffer the consequences. But London’s air really is a silent killer.