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
14.2%
Rate breakdown
9903.05.5510%Section 301 (forced labor) — additional 10% ad valorem on products of Mexico
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