Pollution shortens Londoners’ lives by between nine and 16 months
GAZING out over London’s chimneys, Liverpool’s docks or Edinburgh’s spires can cloud a tourist’s judgment. Air pollution “plagues” Britain, says one UN official. The capital is particularly nasty, and compares poorly with other European cities (see chart). On some days last month particulate levels in London were higher even than in Beijing. On February 17th the mayor, Sadiq Khan, will launch a £10 ($12) “toxic charge” on the most polluting vehicles—broadly speaking those registered before 2005—to come into force in October.
Three pollutants cause most worry: nitrogen dioxide (a gas emitted in vehicle exhausts), ozone (a triatomic form of oxygen which harms the lungs) and tiny particulates, the smallest of which are the most damaging as they get deep into the lungs.
Chronic exposure means Londoners’ lives are between nine and 16 months shorter than they would otherwise be, according to a study by King’s College London. And sudden spikes leave inhabitants gasping. Acute episodes occur in three main ways, says Gary Fuller, who helps run King’s College’s air-quality monitoring network. First, pollution lingers if a layer of cold air forms close to the ground without wind, as happens during chilly months. Second, the circulation of dirty air around Europe’s large cities, as often happens in spring, causes southern England to suffer. And third, in summer, heat and the sun’s ultraviolet rays help to create smog.
British courts have given the government until the end of July to come up with a new plan to cut air pollution. It is likely to focus on cars. Poor air quality is a localised problem that can be caused by nearby airports, factories or power plants. But curbing vehicle-use helps in all cities—and traffic is one area in which Britain’s generally feeble city mayors have some power.
Because about half of certain particulate-matter that vehicles release comes from sources other than the exhaust pipe, such as brakes and tyres, stricter standards on emissions alone do not solve the problem. Paris, Madrid and Athens want to ban diesel cars and vans by 2025.
London will struggle to copy them. Less than a year ago British ministers rejected a diesel scrappage scheme, in which drivers would have been paid for trading in dirty old vehicles for cleaner ones. The political cost of angering diesel drivers, previously encouraged to buy the vehicles because of their lower carbon-dioxide emissions, made such a move impossible. But reports now suggest an updated scheme is under discussion. Mike Hawes of the Society of Motor Manufacturers and Traders, a lobby group, supports such a plan in principle, but frets that even with incentives, the poorest drivers may balk at shelling out for new, cleaner models.
Other schemes are needed. Company cars, which comprise about half of the new ones sold in Britain, are a taxable benefit. The levies paid on them are based largely on the amount of carbon dioxide they produce, making diesel cars the best to buy. Tweaking fiscal rules could change that. Investing in electric and other low-emission vehicles also helps: the government plans to spend £600m on them and the infrastructure they need, such as charging stations, by 2020. Even London’s buses, police cars and black cabs are cleaning up.
More people could stay away from the steering wheel altogether. Lesley Hinds, who has responsibility for transport and the environment on Edinburgh council, says a pilot scheme there to encourage children to walk to school, by closing roads outside nine primaries, has been so successful that it may become permanent. A trade-off exists, however. More space on the streets for pedestrians and cyclists means less for cars, leading to congestion. And the exhaust systems of snarled-up vehicles work less efficiently than those of ones on the move. So the fog of politics makes deciding on what mix of policies to use even harder.