Take a nice deep breath. For thousands of people living in London, that’s a luxury.  

With its plethora of parks, our capital may be one of the greenest cities. But it’s also one of the most polluted. For the last five years, London has been in breach of EU safety limits on NO₂.

I’ve noticed it getting worse. For an instant lesson in air quality, head for the outer reaches of one of the Tube lines and see how fresh the air feels when you step outside. 

Pollution isn’t just an irritant to the throat, nose, or eyes. It’s damaging to health, increasing the risk of lung cancer and chronic lung disease, and driving up hospital admission rates for those with pre-existing lung or heart disease.

Children’s lungs are most vulnerable, yet around 330,000 London kids go to school in areas with illegal levels of pollution.

Pollution has also been linked with damage during pregnancy, including low birth weight and pre-term birth.

I’ll cut a long story short: at least 9,500 deaths a year in London are linked with air pollution.

We may not have the pea-soupers of the 1950s that smothered London in soot and sulphur dioxide for days at a time. But we have a haze of small particles, especially PM2.5s, along with the toxic gas nitrogen dioxide NO₂ (not to be confused with laughing gas because this one isn’t funny).

PM2.5s are fine particles, less than 2.5 micrometres in diameter. They come from things like motor vehicles, power plants, and wood-burning, and they’re harmful because they’re small enough to reach the deepest recesses of the lungs.

Nitrous oxide comes largely from diesel cars, lorries, and buses. It follows that pollution is worse near busy roads, which is often where less advantaged families live. But even short-term exposure to air pollution can damage.

Why am I banging on about it now?

Because on May 5, London elects a new Mayor. As a parent, a doctor, and a Londoner, I whole-heartedly support The British Lung Foundation’s #Londonlungs campaign. It calls for the next Mayor and Assembly members to prioritise lung health.

So much could be done, from tree and hedge planting schemes to improving transport strategy and extending the ultra-low emission zone (ULEZ) eastwards – where there’s a lot of deprivation and air pollution.

You too can help by getting on board and asking all the mayoral candidates whether they pledge to protect Londoner’s lungs. You could also share the campaign on social media with the hashtag #Londonlungs.

What else can you do?

There are obvious individual steps to help protect the lungs and heart, like not smoking.

Driving less, for instance by sharing cars or using public transport, helps drive down vehicle emissions. If you’re buying or leasing a car, choose a low-emission model.

Take the longer route on foot or cycle via a less polluted area if you can. You may be interested in the Clean Space app. 

The British Lung Foundation has some great tips for when air pollution levels are very high. You can find them here.