Processed tobacco contains over 3000 known chemical compounds, many of which have been directly linked to causing cancer in humans. There have been at least 28 carcinogenic agents identified in spit tobacco. As of May 15, 2000, The Department of Health and Human Services (DH&HS) added spit tobacco to the official list of “known human carcinogens.” According to the DH&HS, cancers of the oral cavity have been associated with the use of chewing tobacco and snuff. Their studies indicate that the tumors often arise at the site of the placement of the tobacco.
The most potent of the carcinogens in spit tobacco are the Nitrosamines, especially N-Nitrosamines, which can be detected in the juice produced from the mixture of tobacco and saliva. These Nitrosamines are formed from the nicotiana alkaloids during the processing of the leaves. The nitrosation process continues in the mouth, stimulated by oral bacteria. The FDA regulates nitrosamines levels in food products, however since tobacco is a non-regulated product, the levels often exceed those found in food by 100-1000 times. Because of the close proximity of the tobacco to the oral mucosal during spit tobacco use, the levels of N-Nitrosamines found in the blood of spit tobacco users are 1.5 to 2.8 times higher than the levels inhaled by persons smoking 20 cigarettes per day.
Other potent carcinogens found in spit tobacco include radioactive polonium 210, benzopyrene, arsenic, cyanide, formaldehyde, cadmium and uranium. As potent as these carcinogens are, it is impossible to predict when or if cells will become cancerous as a result of continuous exposure. Consequently, spit tobacco users take a risk of developing oral cancer every time they use the product.
Spit tobacco manufacturers add other compounds to their products to achieve the flavors and textures their customers want. Spit tobacco contains high levels of sodium and in many brands, up to 25% sugar and other sweeteners. Flavorings, such as menthol, cherry, and mint, are added to many of the products to make them more palatable.