Lung cancer is not just a smoking disease. Now granted, the predominate or overwhelming number of lung cancers in the United States are smoking related. But, right behind smoking is asbestos as one of the primary causes of lung cancer. So, you can be a life long non-smoker, but have been occupationally exposed to asbestos and the asbestos exposure can be a cause of your lung cancer. Similarly, you can be a smoker, work in an environment that you were occupationally exposed to asbestos on a regular basis and the science shows that the asbestos exposure combined with your smoking dramatically increases the odds of developing lung cancer. Some studies shows that increase in the order of 20-30 times greater chance that you would develop lung cancer if you had both smoked and been occupationally exposed to asbestos than if you had just smoked and never been exposed to asbestos.. If you worked in an environment that asbestos was being used prior to the mid 1980s could have been refineries, chemical plants, powerhouses, service in the US Navy, construction or in the oil fields all of those kinds of occupations would likely lead to asbestos exposure if they occurred before the mid 1980s.
If you have lung cancer, even if you smoked, asbestos can the cause of your lung cancer.