The whole problem revolves around how little data there actually is.
Basically JUUL invented nic salt a few years ago. Nicotine is alkali. It’s a base. If you mix almost any acid and almost any base there is a reaction and you get a salt. There are thousands of different salts only one of them (NaCl) is table salt. Table salt is is sodium and chlorine. A very strong acid and a very strong base come together (the sodium protonated the chlorine) to make a very stable compound. Weaker acids and bases make much less stable compounds. Nicotine is a very weak base.
This is a very similar process to how some designer drugs are made. Alter the chemical composition and it’s a different chemical with different properties. The issue is designer drugs often have slightly or vastly different behaviors from their original chemicals. Examples are numerous.
JUUL was forced to admit in court that their particular “nic salt” was actually nicotine benzoate. Nicotine reacted with benzoic acid. There are numerous other acids also being used to make “nic salt” though and to my knowledge none, including nicotine benzoate, have had any sort of safety testing.
This doesn’t mean they’re necessisarly dangerous. It just means we don’t know. There is some minimal evidence that indicates (not proves just indicates) that many of the protonated nicotines may (not are just May) be much more addictive than unprotonated nicotine. This was in the form of a chart of blood levels over time for the various chemicals. The protonated nicotines all got into the blood much faster and metabolized much faster as well.
