The October 1996 edition of the journal Science reported the first actual scientific evidence from the cell biology level to link smoking to lung cancer. While many scientists have long been convinced by statistical studies and animal experiments that tobacco causes cancer, a statistical association was not in itself absolute proof. Until now the tobacco industry has always maintained that "the causal link remains to be established." In the published paper, researchers from the University of Texas M.D. Anderson Cancer Centre in Houston and the Beckman Research Institute of the City of Hope in Duarte in California, studied the effects of a cigarette-smoke ingredient on a gene known as p53. The scientists say a chemical found in cigarette smoke has been found to cause genetic damage in lung cells that is identical to the damage observed in many malignant tumors of the lung.
Since 1955, the incidence of lung cancer has risen in all EEC/EU countries (with Denmark and the UK at the top), against a falling rate for all cancers. Lung cancer is by far the commonest cause of cancer for men and smoking is the biggest single cause, accounting for 30% of all cancer and almost all lung cancer. Lung cancer rates in women have increased in all European countries since 1955.
Between 2% and 5% of lung cancer cases can be attributed to radon accumulating indoors.