What is air pollution?
Air pollution is made up of harmful particles (PM) such as diesel soot, tyre and brakewear, and gases. These gases are mainly nitrogen dioxide (N02) and ozone.
Around 300 (1) Bristol deaths are caused each year by Jong-term exposure to air pollution. Around 60-80,000 annual UK deaths are estimated to be caused by air pollution (2).
Air pollution causes more premature deaths than alcoholism or obesity. Only smoking causes more early deaths than air pollution in Britain (3). It has been strongly linked to asthma, lung cancer and cardiovascular illness.
Nitrogen Di-oxide emissions in Bristol
This map is taken from the 2014 Air Quality report for Bristol. It shows the annual mean level of nitrogen dioxide at the sites shown.
The ley point to note is that any site with levels of NO2 above 40 microgm/m3 is above the EU limit. ie it is illegal.
This is all the sites coloured yellow or red. Looking at the report, 52 sites (out of 92) have levels of emissions above the limit.
Who is most at risk?
Air pollution affects us all, but some people are at greater health risk than others:
Children. Pollution is greater at child height and children's lungs are still growing. Children whose schools are near a busy road are at even greater risk.
Older people. The respiratory systems of older people are more vulnerable and take longer to repair or recover than those of younger adults.
Asthma sufferers and people with other respiratory or cardiovascular conditions.
People living near a busy road. Those living within 150 metres are at greater risk. For people living within 50 metres the risk is even higher.
Poorer people. Health inequality is a major problem in Bristol. Poorer people have lower life expectancy and more illness. They are more likely to live near busy roads than rich people, suffering greater exposure to air pollution.
These higher risk groups add up to a very large number of Bristol residents.
But because we are all moving around a highly polluted city, everyone's health is threatened.
1 King's College London, 2015. Understanding the Health Impacts of Air Pollution.
2 Studies published in 2015 by King's College London and the Committee on the Medical Effects of Air Pollutants.
3 Clean Air in London, Guide to health impacts.