Is air pollution a problem?Everyone has a right to clean air. Despite this, millions of tons of harmful gases and particles are released into the air each year. Some of this pollution reaches our lungs with every breath we take.
The black smoke emitted from many diesel engines is one obvious form of air pollution. Many other types of pollution can't be seen but are just as damaging to our health.
Forty years ago coal burning was responsible for most pollution in our cities. The infamous London smog of 1952 resulted in an extra 4,000premature deaths. Today, thanks to smokeless fuels, taller chimney stacks and reductions inindustrial emissions, our cities are relatively free of smoke.
That doesn't mean air pollution has disappeared. Power stations, factories, offices and even our homes all help pollute the air we breathe. Motor vehicles are a major source of air pollution, both in towns and in the country.
One in every five people is particularly at risk from air pollution. People who already have a lung disease, the elderly and children are likely to be especially affected by high levels of pollutants.
Which pollutants cause the problems?Smoke
The majority of city smoke comes from diesel exhausts. In some areas coal burning or electrical generating power stations make up a significant proportion of total smoke.
Large smoke particles are trapped in the upper airways (nose to voicebox), but smaller particles (PM10s) may travel deeper into the lungs.
High levels of PM10s cause increased breathing difficulties in people with asthma, COPD and other lung conditions. They may also causepremature death in older people with heart and lung disease. For this reason, PM10s are now thought to be the most important of the
common air pollutants.
Sulphur dioxide (SO2)
Sulphur dioxide (SO2 ) is produced by power stations and diesel engines. SO2 and smoke produced by coal burning were responsible for the high death rates during the London smog of 1952. Although levels have fallen, SO2 is still a potential health problem in some parts of Britain. Its main effect is on the lungs where it makes the airways narrow. This makes breathing difficult, particularly for people with asthma and young children.
Nitrogen dioxide (NO2)
Nitrogen dioxide (NO2 ) is one of the chemicals produced when fuel is burnt in power stations and cars. NO2irritates the lining of the airways. Together with other pollutants, the levels of NO2 found close to busy roads may have a bad affect on some people with asthma.
Ozone (O3 ) is the main ingredient of modern smog. In Britain ozone levels are highest during hot summers. Ozone irritates the lungs, causing coughing and chest pain. It also stings the eyes, nose and throat. People with lung diseases are particularly at risk, but up to a third of normal healthy people may develop symptoms when they exercise outdoors. This can lead to a decrease in their athletic performance.
Carbon monoxide (CO)
Carbon monoxide (CO) is an odourless, poisonous gas that comes mainly from traffic exhaust. It stops the blood carrying oxygen to the brain, heart and other tissues. People with heart disease are particularly at risk. Cigarette smoke is a big source of carbon monoxide; smokers have much higher levels in their blood than non-smokers.
Lead is bad for the normal development of children. Lead levels are falling but lead in petrol still accounts for 80% of lead in air.
Acid air happens during modern smog when NO2 and SO2 are converted into acids; particularly nitric and sulphuric acid. These form into tiny clouds of acid droplets. It is this 'acid air' which eventually falls as acid rain, damaging plants and trees. We can breathe in fine particles of acid. This causes irritation of the airways, coughing and sometimes wheezing.
How can I protect myself against air pollution?If you are exposed to urban pollution for any length of time you should think about protecting your lungs with a mask. Good masks keep out large particles. People with asthma and others with breathing difficulties may find this makes the air they breathe less irritating. Masks also show motorists how concerned you are about air pollution.
In the UK, advice on levels of air pollutants is available at www.airquality.co.uk. Where levels of air pollutants are high, if you are affected you should spend less time outside, particularly in city streets.
If your asthma is affected by air pollution, follow the treatment plan that you normally use when your condition gets worse.
What can you do about air pollution?Cars are a major source of air pollution in our cities. In 2006 there were 33.4 million licensed motor vehicles in Britain. By the year 2025 there could be 50 million. You can cut down on some pollution if you use unleaded petrol and drive a car with a catalytic converter. If your vehicle uses diesel, be sure to buy ultra clean diesel.
Or drive less - use public transport when you can. If the public transport service in your area is poor, write and tell your local authority why you are adding to air pollution.
If air pollution is to be controlled we need to adopt strict air quality standards for all the main pollutants. And we need to monitor the quality of the air we breathe. Ask your local authority if they measure the pollutants mentioned in this leaflet.