L-Histidine from Canada
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 — Canada → United States
14.2%
Rate breakdown
9903.05.2910%Except for products described in headings 9903.05.85–9903.05.93, articles the product of Canada, as provided for in U.S. note 52 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