Scientists at the University of California, Davis, have discovered that hydrogen peroxide or similar oxidants are what actually cause healthy lung cells to become cancerous.

The researchers say that this finding is important because it may help the tobacco industry develop 'safer' cigarettes by eliminating such substances in the smoke, and give medical researchers a new avenue to developing lung cancer treatments.

'With the five-year survival rate for people with lung cancer at a dismally low 15.5 percent, we hope this study will provide better insight into the identification of new therapeutic targets,' said Tzipora Goldkorn, senior author of a study report, published in The FASEB journal.

During the study, the research team exposed different sets of human lung airway cells (in the laboratory) to cigarette smoke and hydrogen peroxide, and then incubated them for one to two days. They then assessed exposed airway cells for signs of cancer development, along with unexposed airway cells.

The researchers observed that the cells exposed to cigarettes smoke, and the cells exposed to hydrogen peroxide showed the same molecular signatures of cancer development, while the unexposed cells did not.