You have to be of a certain age to remember the days when Britain’s cities were often smothered in a smog of soot and fumes that blocked out the light and choked the lungs.
Or you need to be a visitor to a city like Beijing to experience similar misery today. Here, the air is clean and clear, or so it appears. But it is not. Air pollution in our cities may be largely invisible but it is no less deadly. How radical are we prepared to be to clean up the air we breathe?
A report published this week by the National Institute for Health and Care Excellence (NICE), the body usually associated with telling us which drugs the NHS can or cannot afford to prescribe, produces evidence showing that around 25,000 people in England alone die prematurely each year as a result of air pollution that causes asthma, strokes and cancer. In London, a quarter of children are exposed to levels of air pollution in excess of legal limits; 40% of local authorities preside over towns and cities that breach them too.
The cause of the problem is no longer so much the heavy, smoke-stack industries that spewed the foul stuff out as it established Britain as the world’s first great industrial nation. Most of those industries have gone and our economy now depends predominantly on services, much of it provided by workers sitting in front of computer screens rather than stoking furnaces. What’s fouling the air now is traffic. There were 320 billion vehicle miles driven in Britain last year, an all-time high. It will be even higher this year.
Central to the problem is the huge increase in the use of diesel over the last decade or so – something we have discussed in this column before. NICE reports that nearly half the premature deaths due to air pollution in England can be attributed to diesel engines. They pump out four times the legal level of nitrogen dioxide and twenty times the limit of ‘particulates’, the invisible fine particles we inhale all the time.
The story of diesel is the story of the unintended consequences of trying to do good. The last Labour government had its sights set primarily on the need to do something about climate change and because petrol engines churned out more harmful greenhouse gases than diesel engines, incentives were created to encourage people to switch to diesel cars. The incentives worked and there was a massive switch to diesel cars. Although it was known that diesel was responsible for emissions that harmed air quality, the car industry assured everyone they were getting on top of the problem. We believed them. But then the VW scandal blew up. The result has been that although we may be reducing the harm cars do to global warming we are killing vastly more people through diesel fumes.
According to the NICE report the law of unintended consequences is manifesting itself in other ways that are causing us to breathe toxins. Traffic-calming measures (or driver-enraging measures, as a droll friend of mine calls them) such as speed humps, have gone a long way to reduce the incidence of road accidents caused by driving too fast in built-up areas. But it turns out that they have had a bad effect on air pollution in residential streets because they encourage drivers to speed and then brake. That raises the volume of emissions above what they would be if we drove at a steady speed.
Similarly, noise barriers have fulfilled their task of shielding residential areas from the din of busy roads nearby but at the cost of funnelling air pollutants in a way that increases their concentration. Even trees planted with the purpose of absorbing greenhouse gases and improving air quality may, in some circumstances, cause pollutants to settle because leaves and branches slow air currents.
NICE is proposing a set of what seem like commonsense policies to address the problem. Their main aim is to find ways of encouraging drivers to drive at steady speeds rather than in the accelerate/brake mode that adds to emissions. One way is to increase the number of speed cameras that measure average speed rather than take spot photos of speeding drivers. The idea is that if drivers know that they might be caught over a long stretch of road for exceeding an average speed limit rather than for being over the limit just at the place where the camera is positioned, they will try and maintain an average speed that is within the limit for a longer period. It’s also proposed that speed limits on busy roads should be variable depending on the volume of traffic and that motorways close to urban areas should have 50mph limits. NICE reports that such restrictions in the Netherlands have proved ‘highly cost-effective at reducing air pollution’.
NICE argues also in favour of remodelling speed bumps and persuading planners to build new homes, schools and care homes as far away from busy roads as possible. Living rooms should ideally be situated at the backs of houses rather than at the front.
There has been a broadly polite response to these ideas, though inevitably some drivers will object to further curbs on the speed at which they drive. Some local authorities may also jib at the idea of ripping up speed humps they have spent millions laying down. But the main criticism of NICE’s report is that it is not radical enough.
The fundamental problem, it’s claimed, is the fuel we are using. Petrol causes greenhouse gases and diesel causes air pollutants. Only by adopting other fuels (or by drastically reducing what’s been described as our addiction to hypermobility) can we seriously tackle the problem. Sadiq Khan, the Mayor of London, has announced that the capital is to get its first hydrogen-powered double-decker bus. As for our private cars, campaigners for better air quality say the future is electric.
That may be so but the political problem is that we are so invested in our conventional cars, whether petrol or diesel, that it would cause major upheaval and cost if the government were seriously to try to nudge us into abandoning the vehicles we have in favour of newer, greener technologies. The basic political question is this: how much are we prepared to pay to stop the air we breathe from killing us?
