Poor air quality kills thousands of urban dwellers, so it’s time to start paying attention to the data
Back in July last year, I published a primer on air pollution – what it is, how damaging it can be, and the options we have for measuring and combating it. And today I’m writing about it again. Whilst I’d desperately love to be bringing you good news, I’m afraid I can’t. But the city that is under severe scrutiny today is my beloved London.
London has a long and complicated history with pollution. The period now known as The Great Stink was largely ended by the development of a reliable sewer network. In 1952, a toxic fog smothered the city, killing thousands, and fatbergs are becoming worryingly commonplace. But 2017 may well become another year to add to the pollution history books.
The city breached its annual limits of nitrogen dioxide (NO2) just 120 hours into 2017. A sensor on the always-congested Brixton Road, one of many monitored by King’s College London, recorded a staggering 17 hours in a single day when NO2 concentrations exceeded the “safe” 200 micrograms per cubic meter limit set by the World Health Organization. And at several points in the day, levels of NO2 peaked at 350 micrograms / m3. That news was followed up by a paper, published two weeks ago by the University of Surrey, which showed that Tube passengers are exposed to eight times more air pollution (in the form of particulate matter, or PM) than those who drive to work. That’s despite the fact that, as this study showed, car drivers in London are actually the most polluting commuters.
Dr Prashant Kumar, who led the study, said: “We found that there is definitely an element of environmental injustice among those commuting in London, with those who create the most pollution having the least exposure to it.” Exposure to PM was also shown to depend on the route too – passengers on the District line, which uses trains with closed windows, were exposed to far lower concentrations of PM than those travelling on the Victoria and Northern lines, which each use open ventilation. So there’s definitely an argument to be made for better train design. But, of course the real issue is above ground – with the fuel-belching vehicles on London’s roads.
The city’s Mayor, Sadiq Khan, pledged to battle air pollution in his election campaign, and since taking office, he’s started to deliver on it. His promised Ultra Low Emission Zone is already in the planning, and will come into force in September 2020. In that zone, which covers a large proportion of the city, cars, motorcycles, vans, minibuses, buses, coaches and heavy goods vehicles will need to meet restrictive exhaust emission standards – those who fail to meet them will be fined each time they drive into the city. In January, he tweeted a series of warnings when a period of “very high air pollution” hit the city. But, he was roundly criticized for encouraging people to stay home, rather than telling drivers to stay off the road (prompting this tweet from a journalist at Business Insider).
Just last week, he announced a new scheme called the toxicity charge, or T-charge, which will apply to the most polluting vehicles from 23 October this year. Writing in the Independent, Khan said, “Diesel and petrol vehicles that do not meet the Euro 4 emission standard – typically registered before 2006 – will have to pay an extra daily £10 charge to come into central London. This means that those driving into the Congestion Charge zone between 7am and 6pm on weekdays, in one of these polluting vehicles, will have to pay £21.50 in total.”
Whether that’ll be enough to curb London’s air quality crisis is unlikely, of course, but I hope that, at the very least, this campaign increases awareness of how important air quality measurements are to urban life. I’m not talking about low-cost, personal monitors here, though. As this piece in Nature suggests, the lack of regulation around those devices should make us little skeptical of their promised performance. The co-author of that article, Prof Alastair Lewis, also said in a Guardian interview, that the air pollution monitoring equipment used by governments “typically costs tens of thousands of pounds. If we had a cheap way of doing it, we’d do it the cheap way.”
Thankfully, a number of these government monitoring schemes provide their data in an open format, which has enabled the development of multiple online tools. The newest one is an interactive air quality map titled BreezoMeter, which combines data from governmental sensors, satellites, weather patterns, transportation dynamics and other sources. In my July 2016 article, I also told you about the World Air Quality Index, there’s the Plume Labs database too. Also new-to-the-market is AirVisual, a crowd-sourced platform that provides access to historical, real-time, and forecast air quality data from all over the world. Individual regions also manage this sort of data – millions of Chinese urban dwellers rely on smartphone apps, which report on local air quality on a minute-by-minute basis, radio stations in Mexico City report on ozone levels daily, and since moving to New Zealand in December, I’ve also come across a map maintained by the country’s National Transport Agency.
The air quality crisis cannot be ignored any further. So it’s time to get clued up. Have a look around the data available in your region, familiarize yourself with the latest advice from the WHO, and most importantly of all, try to use your car less. Your lungs, and those of the people around you, will thank you for it.