The darker red areas, concentrated in the centre of London, have the higher percentage of deaths attributable to air pollution. The outer boroughs, excluding Hounslow, have lower levels of air pollution.

Across the world, air pollution is leading to the premature deaths of more than three million people annually – more than HIV/AIDS and malaria combined. In the UK, annually, PM2.5 pollution alone is estimated to lead to the loss of 340,000 years of life.

On average, filthy air cuts eight months off the life expectancy of British people. For the 200,000 people in Britain most directly affected by air pollution, it cuts their life expectancy by two years. Our map above shows the effects of air pollution by borough in London: showing the percentage of deaths in each borough that it is estimated are caused by air pollution.

So what does air pollution do to our bodies?

Lungs

Air pollution inflames people’s lungs and causes them to tighten up. It contributes to asthma and exacerbates it in individuals who already have it. PM2.5 and PM10 (tiny air particles) can penetrate deep into people’s lungs – PM2.5 is thought to have the biggest health impact. Nox also causes inflammation of the airways – and in the long term increases symptoms of bronchitis in asthmatic children.

In the short term, more people are admitted to hospital for heart and lung problems when air quality is bad. This is particularly a problem for people with asthma or COPD (a group of lung conditions), and older people – most asthma sufferers say poor air quality worsens their symptoms. At very high levels of air pollution, even normally healthy individuals may experience a sore throat and eyes or a tickly cough.

Longer term it has huge impacts – like smoking, it leads to an increased risk of lung cancer. Diesel has been classified by the WHO as a class one carcinogen.

Perhaps most worryingly, air pollution is also known to stunt the growth of children’s lungs. Studies in East London have found schoolchildren as young as eight can have up to 10% less lung capacity – and the same study found that London’s Low Emission Zone had made no difference to children’s health.

Heart

PM2.5 is small enough that not only does it get into the lungs, it also penetrates into the bloodstream.

In the 1990s, researchers began to realise that air pollution also affects the heart – and given the prevalence of health and circulatory problems in the UK, the contribution of air pollution to this is a crucial issue. Air pollution also contributes to cardiovascular disease.

Brain

Researchers have begun to link air pollution with degenerative disorders such as dementia. One study even found that older women who live in places with particulate air pollution (PM2.5 and PM10) are as much as 92% more likely to develop dementia.

Womb

Air pollution is now recognised to have an effect on babies – and if mothers are breathing poor quality air, it can even affect them in the womb. It also lowers the birthrate amongst women, can cause premature birth – and contributes to a low birthweight, according to a study of children born just after the Beijing Olympics.

What can I do?

• • • Join Friends of the Earth’s air pollution campaign.
    • Walk, cycle or take public transport  – instead of driving.
    • Write to your MP about the issue.
    •  Read our article on what you can do to protect yourself.

Follow our Clear The Air series this week to find out more about the air pollution crisis in our boroughs.