1. The water-vapour transmission of four polyhydric alcohols has been determined for the products themselves as well as after a 3 % application on a flue-cured tobacco type. These polyhydric alcohols are glycerine, sorbitol, propanediol-1,2 and butanediol-1,3. The butanediol-1,3 shows the most hygroscopic properties.
2. Of the four products examined, the same butanediol-1,3 has the strongest fungistatic effect.
3. The taste of the cigarettes with butanediol-1,3 is better than that with sorbitol or propanediol-,1,2 (and diethyleneglycol).
4. The smoke nicotine content of cigarettes, the tobacco of which is treated with 3 % butanediol-1,3 is significantly lower than that of cigarettes out of the same type of tobacco with the other humectants or out of untreated tobacco. This can possibly be caused:
a. Partially by a relatively high moisture equilibrium of the tobacco.
b. Partially by a selective nicotine absorption in the butt (not in the filter).
c. Possibly there is still another effect, because the nicotine totals show a minimum with the glycol cigarettes. However, further experiments were not done.