 Approximately 8.2 million 3.3 of Americans 12 years of age are current smokeless tobacco ST users, and the prevalence of ST use has increased over the past three years. ST is increasingly being promoted as a harm reduction strategy for cigarette smoking, and two of the worlds largest cigarette manufacturers have entered the ST market. ST use is estimated to be the greatest exogenous source of human exposure to cancer-causing nitrosamines. ST has been associated with oral and extra-oral cancer as well as cardiovascular and cerebrovascular mortality. 