I do not think there is, and I am not surprised by the move to regulate it. I've actually been expecting the FDA to step in at some point. There is nothing wrong with making sure a product conforms to standards--that its nicotine content falls within a specific range, that its flavorings conform to food industry standards, that it uses water of a specific purity, that its mechanical components are not prone to injury-causing failure, etc.
Your point about mission creep is a valid one. While there is a strong case to be made for the FDA in its role of enforcing product safety standards, there is not a case to be made for it to attempt to control consumer use of such products. Unfortunately, liberal politicians see the FDA as a tool for enforcing lifestyle decisions on the public (e.g. your food and beverage choices)--and the public, seeing the FDA used in this way, concludes incorrectly that the FDA has no legitimate purpose.
Can you point out the enumerated power that the States gave to the national government to assume that role?