How can air pollution cause cancer?

  • Exposure to air pollution increases the risk of lung cancer.
  • On average air pollution levels in the UK are low, so the increased risk of cancer for each individual person is generally small.

Air pollution can be separated into outdoor and indoor air pollution. Both can increase the risk of cancer and diseases such as respiratory and heart diseases.

What is outdoor air pollution?

Outdoor air pollution is a mixture of tiny dust-like particles and substances in the air. Outdoor air pollution can be man-made, such as fumes from vehicles or factories, vehicle tyre and brake wear and smoke from burning fuels like wood or coal. But it also includes natural substances, such as wind-blown dust.

What is the cancer risk from outdoor air pollution?

In 2013, the International Agency for Research on Cancer (IARC) confirmed that outdoor air pollution is a cause of cancer. Tiny dust-like particles just millionths of a metre wide, called ‘particulate matter’, make up a part of outdoor air pollution. The smallest particles known as PM10 and PM2.5 are linked to lung cancers caused by pollution. It is not fully understood how these particles can damage DNA in cells and cause cancer.  

How big is the risk of outdoor air pollution in the UK?

The UK has fairly low levels of outdoor air pollution compared to other countries around the world. And levels of most pollutants including PM10 and PM2.5 are within the EU limits. On average, levels of both PM10 and PM2.5 in the UK are low, so the increased risk for an individual is fairly small. However, levels can peak and drop depending on the time of year and even the weather.

Overall, almost 1 in 10 lung cancer cases in the UK are caused by exposure to outdoor air pollution. However, it’s important to keep risks in perspective. Smoking has a much bigger effect on the risk of developing lung cancer than air pollution.

Air pollution levels tend to be higher in UK towns and cities, especially in southern and east areas of the UK. You can find out more about air pollution in your area on the UK-AIR website.  

What can I do to reduce my cancer risk?

There is no need to avoid going outside because it is difficult for anyone to avoid air pollution completely. There are things you can do to reduce your cancer risk in general such as not smoking, keeping a healthy weight and staying safe in sun. Find out more here.  

How can air pollution levels be reduced?

As individuals we can all play our part to help to reduce air pollution levels by trying to avoid creating more of it. Choosing active travel options like walking and cycling rather than using cars can help reduce pollution levels from transport and it is a great way to be more active.

Everyone has a right to be healthy. Cancer Research UK supports national and local strategies to reduce outdoor air pollution. In particular, we support the prompt introduction of clean air zones and the promotion of cycling and walking in cities.

What is indoor air pollution?

Indoor air pollution can have many sources. For example, the burning of solid fuels to heat homes and to cook with could be a source, but this is less common in the UK.  The main source of indoor air pollution in the UK is second-hand smoke from cigarettes.

Second-hand smoking, also known as passive smoking, can cause lung cancer and other health problems like heart disease.

Most exposure to second-hand smoke happens in the home and is particularly dangerous for children.

If you are a smoker, smoking outside ,well away from the home can help reduce exposure for others. And stopping smoking will have benefits for both your health and others.

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