Relationships Between Smoking and Lung Cancer

A great deal of attention has been paid to the relationship between smoking and lung cancer. Indeed, many people automatically assume that relationship. It is therefore important to understand that while smoking is certainly a potential cause of lung cancer, it is not the sole cause of lung cancer in humans. Statistics have shown that cigarette smoking alone increases the risk of lung cancer by a factor of 10 or so; heavy asbestos exposure alone increases the risk of lung cancer by a factor of 5 or so; and the combination of the two independent carcinogens increases the risk factor by about 50 times.

Thus, you do not merely add the risks posed by asbestos to the risks posed by cigarette smoking. The combination of asbestos and smoking multiplies the risk by an unquantifiable, but significantly greater, factor. This relationship is what is referred to as the "synergistic effect" of smoking and asbestos exposure. In short, one plus one does not equal two-it equals five or more.