A smoker has a risk of lung cancer because of smoking that is much greater than that of individuals who have never smoked, but, even so, that person has a fairly good chance of not developing a lung cancer based on the risk seen in the population of all smokers. If that smoker does develop lung cancer, the lung cancer will be caused by the tobacco smoke and could have been avoided if the person had never smoked. If we look closer at the population of smokers with a risk of lung cancer, we can identify criteria that select those with the most risk of developing lung cancer based on the cumulative dose of tobacco smoke that they are exposed to and to factors of individual susceptibility. However, the causal association between tobacco smoke and lung cancer is so strong that we seldom do more than obtain a smoking history and do not require a detailed analysis of corroborating evidence to link a smokers lung cancer to tobacco smoke in the vast majority of cases.
Many studies examine only the risk of lung cancer for asbestos-exposed populations and do not investigate the criteria for ascribing an individuals lung cancer to asbestos exposure. Studies have demonstrated that certain occupations and populations of workers commonly have higher asbestos exposures and greater risks of asbestos-related diseases than others. For compensation, however, a worker must substantiate the individual claim (Philip T. Cagle, 2008).
