A person is at risk of developing lung cancer if they: smoke; are over the age of 50; work in industries where substances such as asbestos, nickel, chloromethyl ether, chromium, beryllium or arsenic are used; have or have had a lung disease; have a family history of lung cancer; are former smokers; have been exposed to second-hand smoke over many years or; have been exposed to radon. (Tenet Heal