27 C.F.R. § 21.38 Formula No. 4.
Title 27 - Alcohol, Tobacco Products and Firearms
(a) Formula. To every 100 gallons of alcohol, or to every 100 gallons of rum of not less than 150 proof, add:
One gallon of the following solution: Five gallons of an aqueous solution containing 40 percent nicotine; 3.6 avoirdupois ounces of methylene blue, U.S.P.; and water sufficient to make 100 gallons. (b) Authorized uses. (1) As a solvent:
460. Tobacco sprays and flavors. (2) Miscellaneous uses:
812. Product development and pilot plant uses (own use only).
Title 27: Alcohol, Tobacco and Firearms
PART 21—FORMULAS FOR DENATURED ALCOHOL AND RUM
Subpart D—Specially Denatured Spirits Formulas and Authorized Uses
§ 21.38 Formula No. 4.
