Air pollution from traffic is killing vast numbers every year - and the problem is getting worse. Andrew Marszal
16 Feb 2010
What is the biggest killer on our roads? It's not black ice, or drunk driving, or even badly installed accelerator pedals. In fact, it's air pollution – and it's getting worse. According to the most recent official figures – published back in 1998 – up to 24,000 people in Britain die before their time every year as a result of air pollution caused by vehicles, compared with 2,600 killed in road accidents. Yet EU researchers say that this figure could represent less than half of the true toll, given that new studies are increasingly linking long-term exposure to traffic pollution to a range of chronic diseases.
Last week, the House of Commons's Environmental Audit Committee heard evidence that about 35,000 people – or 51,500, if you use the methodology devised by the European Topic Centre on Air and Climate Change – died prematurely in 2005 as a result of exposure to tiny airborne particles generated by traffic. Professor Frank Kelly, an environmental health expert at King's College London, claimed that about 3,500 and possibly up to 8,000 deaths in London alone could be attributed to this kind of pollution.
At first sight, this idea seems strange. The pea-souper fogs that once defined our capital city have long vanished, the last straw being the so-called Great Smog of 1952, when a thick cloud of pollution settled over London and penetrated deep into its inhabitants' lungs for five days. The resultant 12,000 deaths led to new policies that aimed to cut industrial emissions – the main source of air pollution at the time. A couple of decades later, the fumes caused by traffic congestion (most notoriously in southern California) seemed to have been similarly defeated by the catalytic converter.
Although modern pollution is less visible, it is no less prevalent. Road transport is now responsible for up to 70 per cent of air pollution in urban areas, the two main culprits being nitrogen dioxide – increasingly believed to be a major cause of asthma in children and present at higher levels in London than any other capital in Europe – and tiny airborne particulates. Both are emitted by the combustion of fuel, although other particulates – sometimes as much as half of the total – can come from road dust and brake and tyre wear, which are harder to measure – or regulate.
Despite tighter emissions standards, both nitrogen dioxide and the particulates have remained in the atmosphere thanks to the rise of diesel engines, which emit less carbon dioxide but produce smaller and more chemically complex particulate matter damaging to human lungs. Indeed, diesels have risen from powering eight per cent of new car registrations in the early 1990s to more than 40 per cent today, while traffic volumes have risen by a quarter.
So what are the dangers? A report by the US-based Health Effects Institute, which draws on more than 700 recent studies, shows "strong evidence" that cardiovascular and lung disease can be the result of long-term exposure to high levels of air pollution. Particularly dangerous manifestations can include atherosclerosis – a hardening of the arteries which can lead to heart attack or stroke – and a narrowing of the airways known as chronic obstructive pulmonary disease. These findings were not factored into the 12-year-old Defra figures for early deaths, which are yet to be updated to include the long-term effects of exposure. Nor did they include the fact that the HEI report points to stunted lung development in children and possibly complications during pregnancy as further likely hazards for those in highly exposed areas, such as homes sited within 500 metres of a major road (a category that includes nearly 12 million people in England alone, including a disproportionate number of poorer families and ethnic minorities). According to one study, children growing up with high exposure are unlikely ever to attain full lung function.
In its submissions to the Environmental Audit Committee, the Department for Transport insisted that adequate efforts were being made to reduce the impact of harmful traffic emissions. However, Graham Pendlebury, the department's environment and international director, has had to concede that a relatively small proportion of our resources is committed to air quality. Germany, for example, has roughly 40 "low emission zones" in city centres, designed to reduce pollution in the worst-hit areas; here, we only have one, which operates across London.
No wonder, then, that Britain has breached EU limits on airborne particulates (which are based on World Health Organisation recommendations) every year since the rules came into force in 2005, and is equally woeful in terms of nitrogen dioxide, for which new rules came in this year. EU limits for nitrogen dioxide for the whole of 2010 were breached in less than a month in London, and scores of town and cities are set to exceed the levels now in force.
The European Commission has launched legal action to force Britain to comply (the Government has until June to apply for an extension, although its last appeal for such was rejected back in December). If we are punished, the cost is expected to be about £300 million. Embarrassingly, the process will come to a head around the time of the 2012 Olympics, which London has promised will be the greenest ever.
As if this wasn't bad enough, the National Audit Office revealed last month that Britain is not on target to meet even its own objectives on five different air pollutant types. Progress in improving air quality has, it said, largely stalled over the past decade. Particulate matter is still most heavily concentrated in London, though several other cities, including Glasgow and Birmingham, avoided EU fines only after last-minute appeals for extensions.
What can be done? Giving evidence to the Commons committee, Prof Kelly said that the Government, the Mayor of London and local councils had to act decisively, as in the same way they had over obesity or smoking, adding that we need to reduce the number of vehicles on the roads "by at least 20 to 30 per cent". Some experts say that emissions from power stations and domestic gas boilers must also be addressed, with greater use made, for example, of clean renewable energy, and the promotion of the boiler scrappage scheme, which subsidises cleaner, modern gas boilers.
Others point out that air pollution and its devastating impact on public health have long been kept in the shadows by the more headline-grabbing concerns of the green movement: the decision to promote diesel engines, on the basis of their relatively lower carbon footprint, is a classic example. It would be ironic if we succeeded in saving the planet, only to choke to death in the process.