L-Histidine from Mexico
L-Histidine essential amino acid for histamine production and metal chelation in supplements. HTS 2922.49.49 despite imidazole ring, classified by amino acid function. Used in allergy research and nutrition.
Duty Rate — Mexico → United States
4.2%
Rate breakdown
9903.03.030%Articles the product of any country, as provided for in subdivision (aa)(ii) of U.S. note 2 to this subchapter
Import Tips
• Imidazole content doesn't trigger heterocyclic classification per chapter structure
• Chelate formation documentation for pharma applications
• Buffer properties require pKa declaration for research imports