These carcinogens are found only in tobacco. Wide variation in TSNA levels was observed among ten cigarette brands likely due to differences in tobacco blending practices used by the different manufacturers. In partnership with Florida, CDC assessed the nicotine, pH, and moisture content of six moist snuff products. These products reflected a cross-section of the products from the five leading U.S. moist snuff brands sold in the U.S. during 1997. The analysis found substantial differences in the pH, the amount of moisture and nicotine, and the percentage of free nicotine in these brands.
Free nicotine is the chemical form most readily absorbed into the bloodstream.