A new study has identified the mechanism by which air pollution leads to cancer. The nature of the discovery alters medical our understanding of how tumours arise.

The research was conducted at the Francis Crick Institute in London, and it finds that rather than causing direct damage, air pollution functions to cause old, damaged cells to move out of a state of ‘hibernation’.

This is based on the damage to a cell’s DNA forming as it ages. At some future point a trigger makes it cancerous. This may explain, for example, why non-smokers can develop lung cancer. Instead, air pollution is the mechanism in some cases.

This finding alters the established view of how cancer is formed. Here, cancer starts with a healthy cell. As the cell acquires more and more mutations in its genetic code it becomes a cancer and grows uncontrollably.

The finding potentially explains how hundreds of cancer-causing substances act on the body. Based on the discovery if may now become possible to develop drugs that stop certain cancers from forming.