Some of the variation in weight that is not. accounted for in Tables 1 or 2 is due to the variation. in the wood density of the different species. AdjustÂ­. ment factors have been developed to account for the. variation by species. The adjustment factors were. each species by the average density of all of the trees.
For example, regular smoking increases the risk of developing lung cancer; therefore smoking is a risk factor for lung cancer. The risk factors for mouth cancer include: 1  Smoking - studies indicate that a 40-per-day smoker has a risk five times great than a lifetime non-smoker of developing oral cancer.  Chewing tobacco.
Mouth cancer is caused by an uncontrolled growth of cells in the mouth. Mouth cancer includes cancer that starts anywhere in the mouth, including: 1  lips. 2  tongue. 3  gums. 4  floor of the mouth or under the tongue. 5  inside the cheeks and lips. 6  roof of the mouth (the palate). 7  area behind the wisdom teeth.