London Smog: Just How Bad Is the Air in the UK Capital?

This article originally appeared on VICE UK.

London's air is not good for Londoners. You may have already worked this out for yourself via all that black stuff you regularly hack up after your morning cycle into work. However, last week the campaigning group Clean Air in London released a damning report demonstrating just how harmful the capital's air pollution can be; according to their findings, 1,300 people have died prematurely in 2015 alone as a result of London's diminishing air quality.

It's a bold, headline-grabbing figure, but what does it actually mean?

"The figure of 1,300 people dying prematurely in London as a result of air pollution so far this year is a statistical estimate," says Dr. Heather Walton of King's College London. "This figure is based on fine particulate air pollution, PM2.5. Studies of large groups of people show that there is a correlation between the annual average PM2.5 concentrations across a city and the numbers of deaths—or, more precisely, the timing of their deaths."

PM2.5 relates to particles that are 2.5 micrometers or smaller in diameter. They can only be seen under an electron microscope (which retail at roughly £65,000 [$100,000]), so your chances of dodging them on the high street are pretty slim.

"Particulate matter contains mixtures of many components, including heavy metals, polycyclic aromatic hydrocarbons, and other components," Dr. Walton explains. Once all these little particles are swirling about inside your lungs, they can cause something called oxidative stress.

"This is where antioxidant defenses in the lung are depleted, reactive compounds are produced and reactions occur that change parts of lipid, DNA, and protein molecules within the lung," she says. "The body responds to this by generating an inflammatory response in the lung, and this, in turn, can change the composition of the blood in a way that increases the risk of damage to the heart, or can lead to neural messages that change the rhythm of the heart. Even if these processes occur to only a minor degree, it can still be a problem in people with heart or lung disease who will already have increased oxidative stress and increased levels of inflammation."

That's why the report uses the clunky phrase "premature deaths." You're pretty unlikely to suddenly develop critical issues as a result of air pollution, but if you're already sick then all the nasty crap being churned through your lungs is only going to make you sicker.

Other junk in the air includes Nitrogen Dioxide (NO2), which can cause bronchitis, asthma, and other respiratory conditions; and ground-level o-zone, which creates a summertime smog—perfect for adding character to photographs of urban foxes, but also capable of inflaming the lungs, as well as generally irritating the eyes, nose, and throat.

The final problem that Dr. Walton identifies is one that might make you feel a little like you're living in a Simpsons Movie–esque domed city designed specifically to kill you both slowly and painfully. "Exposure to air pollution is ubiquitous," she warns. "So even if it is a weaker risk factor than other risk factors, such as smoking, it can still have an extensive public health impact because so many people are exposed."

Sucking in London's grim, dirty air is an inevitable part of living in the city. Rather than frolicking on the Outer Hebrides, our unsullied lungs bathed in particulate-free air, we're all destined to engage in daily battle with this invisible enemy. Even if you head to Hampstead Heath for the day and feel like you're probably breathing in clean air because you're surrounded by bushes and insects you've never seen before, think again: it's awful all over the city, with Kensington and Chelsea taking the absolute top position in terms of Air Most Likely to Kill You Early.

The inexorable spread of shitty air has led to something of a fight back within the scientific community. The Clean Air in London app, developed by founder Simon Birkett, alerts the user on days when pollution is forecast to be high and gives them advice on how to reduce their emissions and exposure to air that's going to be particularly harmful.

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Still, these are only baby steps into a very grown-up problem; Jenny Bates, air pollution campaigner for Friends of the Earth, calls air pollution the "biggest environmental cause of premature death," claiming it's responsible for "killing 29,000 people prematurely a year from fine particles, but this could double if the effects of toxic NO2 gas are added, and there are health effects below current EU legal limits."

Bates also observes that "air pollution is carcinogenic and hits the most vulnerable and disadvantaged hardest." The link between air pollution and deprived areas has been long established—a 2005 report on the issue concluded that "significant sources of pollution are disproportionately located in more deprived areas," and that, while the health issues varied on a site-by-site basis, the sense of "place stigma" surrounded heavily polluted areas remained.

So London's atmosphere, which once inspired Monet but now inspires that guy on the tube to cough directly into your mouth, disproportionately impacts areas already underrepresented by Westminster's interests. Barry Gardiner, MP for leafy Brent North and Shadow Environment Minister, has responded to the figures by stating that "1,337 people have already died as result of air pollution, yet the mayor's proposals will not bring this down to safe levels until 2030. We need decisive action now to protect our children; not vague promises for 15 years down the line."

Simon Birkett, founder of Clean Air in London, believes there's one simple move to be made if we want to start making progress now. "The biggest single step London could take to address this crisis would be to ban all diesel vehicles from the most polluted places, [in the same way] coal was banned so successfully almost exactly 60 years ago," he tells me over email.

Air pollution isn't going to kill you today, but just like those who worked with asbestos in the 1980s, there's a ticking clock looming over our heads. With an increased number of environmentally efficient vehicles being produced—including electric buses—and plans to safeguard parts of London as "Ultra-Low Emission Zones" (which will, presumably, protect social housing and not just Hyde Park and Blackheath), things might get better eventually. But we've still got a number of years to spend at this dangerous level, so get used to shelling out more than anyone else in the UK on rent while your health continues to suffer.

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