What causes London’s air pollution, and other smoggy questions

London. (We think.) Image: Getty.

I fear my chronic sore throat may be caused by air pollution – but I’m too nervous to ask the GP. I’m not one of the “very sensitive individuals” that this Defra blog says should be concerned. I am not old, pregnant, nor suffering from a pre-existing lung or heart condition. And even if the pollution is giving me gip, I can hardly expect our over-stretched NHS to prescribe a cure for breathing.

But is it time to ditch my press-on-regardless mentality with regard to air quality? On Monday last week, pollution levels in London were so high that Mayor of London Sadiq Khan issued his first “very high” alert. When levels are this bad, the government’s Daily Air Quality Index recommends that even healthy members of the public “reduce physical exertion, particularly outdoors”.

On a day to day basis, Defra advises that UK air pollution “is not expected to rise to levels at which people need to make major changes to their habits to avoid exposure”.

But London's most recent pollution-peak is not a one off. Brixton Road in Lambeth breached the EU’s legal limit of annual exposure to Nitrogen Dioxide (NO₂) within the first five days of 2017. And the consequences of long-term exposure, even to low level ambient pollution, are not to be sniffed at. The Royal College of Physicians estimates that outdoor air pollution is a contributing factor in around 40,000 deaths per year. The estimate on the Defra website is 25,000.

So when do the short term effects, such as sore eyes and throat, become symptoms of a chronic health concern? When does an air pollution “episode” become long term exposure?

The short and shocking answer is that if you lived in London for the whole of 2016, then you likely exceeded the limits for long-term exposure to at least one kind of air pollution. According to Timothy Baker, principal analyst at The London Air Quality Network, “the vast majority of London exceeds its long term annual average of Nitrogen Dioxide levels”.

Lawyers from ClientEarth have even taken the government to court over the country’s illegal levels of NO₂ – not just in London, but in 37 out of 43 zones across the UK.

So if you think it’s time to de-smog your knowledge of the subject, here’s what you need to know:

How bad is London, really?

We are used to seeing contemporary images of Beijing’s brown haze or older photos of Britain's “peasouper” smogs – and, in comparison, London's recent fog appears a relatively picturesque affair.

But don’t be fooled. According to The Telegraph, at 3pm on Monday 23 January the government’s Air Quality Index hit a peak of 197 micrograms per cubic metre for particulate matter. That’s 190 micrograms higher than the World Health Organisation’s upper safety limit and 7 micrograms higher than notoriously unhealthy Beijing.

What are these pollutants doing to me?

report published last year by the Royal College of Physicians, argued that the serious effects of long-term exposure to air pollution, even at lower levels, “cannot be ignored”. Cancer, asthma, stroke and heart disease, diabetes, obesity, and dementia are just some of the conditions to which air pollution has been linked. There is even evidence to suggest that it may be damaging your mental health.

Young children are particularly at risk. This passage from the RCP report is particularly chilling: “Children living in highly polluted areas are four times more likely to have reduced lung function in adulthood. Improving air quality for children has been shown to halt and reverse this effect. For older people, living near a busy road speeds up the rate of lung function decline that is associated with ageing.”

You can’t see it. You often can’t smell it. So how do we even know air pollution exists?

The government’s Daily Air Quality Index measures for particle pollutants of size PM2.5 and size PM10: this means that the air contains tiny particles of soot (black carbon), metals and other compounds that are either two and one half microns or less, or ten microns or less, in width. It also measures the levels of the gases Nitrogen Dioxide (NO₂), Sulphur Dioxide (SO₂) and Ozone.

DEFRA collects this data from over 300 monitoring sites across the UK, which you can find listed on this interactive map. The most intensive measuring network in the country, however, is run by the London Air Quality Network at Kings College London. The team here uploads hourly pollution indexes for the capital to their website and apps.

What causes it and how can it be stopped?

Timothy Baker from The London Air Quality Network, says that last Monday’s peak was due to a build up of localised fumes, pollution drifting in from the continent, and a period of windless weather that failed to disperse the dirty air.

Some of the localised pollution contained high levels of particles from wood burning fires – possibly from families putting their feet up on a chilly Sunday afternoon. But don’t let the temptation to moan about fire-place owners distract you from the most pressing cause of London’s pollution problem: the nitrogen dioxide emissions resulting from an increased use of diesel cars.

“Diesel is a lot worse than petrol,” says Baker. “Petrol cars over the last twenty years have had their act cleaned up [...] but modern diesel cars are only just meeting the same sort of standards that they should have been meeting ten years ago.”

What can I do to protect myself?

Checking the daily air pollution forecasts in your area is a sensible place to start. Then you can decide whether or not to exercise outside, avoid busy roads, or don (as I’m considering) your very own Darth-Vader-style protection mask.

What can be done by others?

There is hope. Last week, Sadiq Khan announced funding for audits that will identity ways London schools can lower their exposure to pollution, while in Paris, authorities responded to pollution peaks by imposing temporary driving restrictions and making public transport free.

But more action is also needed from the government. “The government has consistently failed to deal with air pollution across the UK,” says ClientEarth lawyer Anna Heslop. ““We get these smogs every winter, so besides the air quality plans which the government has been ordered to improve by the UK High Court, we need action in the very short term, especially in our bigger cities.”

In the meantime (cough), I should perhaps take a deep breath and book that GP appointment.

India Bourke is editorial assistant at the New Statesman, where this piece was originally published

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Owning public space is expensive. So why do developers want to do it?

Granary Yard, London. Image: Getty.

A great deal has been written about privately owned public space, or POPS. A Guardian investigation earlier this year revealed the proliferation of “pseudo-public spaces”. Tales of people being watched, removed from or told off in POPS have spread online. Activists have taken to monitoring POPS, and politicians on both sides of the pond are calling for reforms in how they are run.

Local authorities’ motives for selling off public spaces are normally simple: getting companies to buy and maintain public space saves precious public pounds. Less straightforward and often overlooked in this debate is why – given the maintenance costs, public safety concerns and increasingly unflattering media attention – developers would actually want to own public space in the first place.

To answer that question it’s important to note that POPS can’t be viewed as isolated places, like parks or other public spaces might be. For the companies that own them, public spaces are bound up in the business that takes place inside their private buildings; POPS are tools that allow them, in one way or another, to boost profits.


In some cities, such as Hong Kong and New York, ownership of public space is a trade-off for the right to bend the rules in planning and zoning. In 1961 New York introduced a policy that came to be known as ‘incentive zoning’. Developers who took on the provision of some public space could build wider, taller buildings, ignoring restrictions that had previously required staggered vertical growth to let sunlight and air into streets.

Since then, the city has allowed developers to build 20m square feet of private space in exchange for 80 acres of POPS, or 525 individual spaces, according to watchdog Advocates for Privately Owned Public Space (APOPS).

Several of those spaces lie in Trump Tower. Before the King of the Deal began construction on his new headquarters in 1979, he secured a pretty good deal with the city: Trump Tower would provide two atriums, two gardens, some restrooms and some benches for public use; in exchange 20 floors could be added to the top of the skyscraper. That’s quite a lot of condos.

Shockingly, the current president has not always kept up his end of the bargain and has been fined multiple times for dissuading members of the public from using POPS by doing things like placing flower pots on top of benches – violating a 1975 rule which said that companies had to provide amenities that actually make public spaces useable. The incident might suggest the failure of the ‘honour system’ under which POPS operate day-to-day. Once developers have secured their extra square footage, they might be tempted to undermine, subtly, the ‘public’ nature of their public spaces.

But what about where there aren’t necessarily planning benefits to providing public space? Why would companies go to the trouble of managing spaces that the council would otherwise take care of?

Attracting the ‘right sort’

Granary Square, part of the £5bn redevelopment of London’s Kings Cross, has been open since 2012. It is one of Europe’s largest privately-owned public spaces and has become a focal point for concerns over corporate control of public space. Yet developers of the neighbouring Coal Drop Yards site, due to open in October 2018, are also making their “dynamic new public space” a key point in marketing.

Cushman Wakefield, the real estate company in charge of Coal Drops Yard, says that the vision of the developers, Argent, has been to “retain the historical architecture to create a dramatic environment that will attract visitors to the 100,000 square feet of boutiques”. The key word here is “attract”. By designing and managing POPS, developers can attract the consumers who are essential to the success of their sites and who might be put off by a grubby council-managed square – or by a sterile shopping mall door.

A 2011 London Assembly Report found that the expansion of Canary Wharf in the 1990s was a turning point for developers who now “assume that they themselves will take ownership of an open space, with absolute control, in order to protect the value of the development as a whole”. In many ways this is a win-win situation; who doesn’t appreciate a nice water feature or shrub or whatever else big developer money can buy?

The caveat is, as academic Tridib Banerjee pointed out back in 2001: “The public is welcome as long as they are patrons of shops and restaurants, office workers, or clients of businesses located on the premises. But access to and use of the space is only a privilege and not a right” – hence the stories of security guards removing protesters or homeless people who threaten the aspirational appeal of places like Granary Square.

In the US, developers have taken this kind of space-curation even further, using public spaces as part of their formula for attracting the right kind of worker, as well as consumer, for nearby businesses. In Cincinnati, developer 3CDC transformed the notoriously crime-ridden Over-The-Rhine (OTR) neighbourhood into a young professional paradise. Pouring $47m into an initial make-over in 2010, 3CDC beautified parks and public space as well as private buildings.

To do so, the firm received $50 million  in funding from corporations like Procter and Gamble, whose Cincinnati headquarters sits to the South-West of OTR. This kind of hyper-gentrification has profoundly change the demographics of the neighbourhood – to the anger of many long-term residents – attracting, essentially, the kind of people who work at Procter and Gamble.

Elsewhere, in cities like Alpharetta, Georgia, 3CDC have taken their public space management even further, running events and entertainment designed to attract productive young people to otherwise dull neighbourhoods.

Data pools

The proposed partnership between the city of Toronto and Sidewalk Labs (owned by Google’s parent company Alphabet) has highlighted another motive for companies to own public space: the most modern of all resources, data.

Data collection is at the heart of the ‘smart city’ utopia: the idea that by turning public spaces and the people into them into a vast data pool, tech companies can find ways to improve transport, the environment and urban quality of life. If approved next year, Sidewalk would take over the mostly derelict east waterfront area, developing public and private space filled with sensors.

 Of course, this isn’t altruism. The Globe and Mail describe Sidewalk’s desired role as “the private garbage collectors of data”. It’s an apt phrase that reflects the merging of public service and private opportunity in Toronto’s future public space.

The data that Sidewalk could collect in Toronto would be used by Google in its commercial projects. Indeed, they’ve already done so in New York’s LinkNYC and London’s LinkUK. Kiosks installed around the cities provide the public with wifi and charging points, whilst monitoring traffic and pedestrians and generating data to feed into Google Maps.

The subway station at Hudson Yards, New York City. Image: Getty.

This is all pretty anodyne stuff. Data on how we move around public spaces is probably a small price to pay for more efficient transport information, and of course Sidewalk don’t own the areas around their Link Kiosks. But elsewhere companies’ plans to collect data in their POPS have sparked controversy. In New York’s Hudson Yards development – which Sidewalk also has a stake in – ambiguity over how visitors and residents can opt out of sharing their data when in its public square, have raised concerns over privacy.

In Toronto, Sidewalk have already offered to share their data with the city. However, Martin Kenney, researcher at the University of California at Davis and co-author of 2016’s ‘The Rise of the Platform Economy’, has warned that the potential value of a tech company collecting a community’s data should not be underestimated. “What’s really important is the deals Toronto cuts with Sidewalk may set terms and conditions for the rest of the world," he said after the announcement in October.

The project could crystallise all three motives behind the ownership of POPS. Alongside data collection, Sidewalk will likely have some leeway over planning regulations and will certainly tailor its public spaces to its ideal workers and consumers – Google have already announced that it would move its Canadian headquarters, from their current location in Downton Toronto, into the first pilot phase of the development.

Even if the Sidewalks Lab project never happens, the motives behind companies’ ownership of POPS tell us that cities’ public realms are of increasing interest to private hands.

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