dl-Tryptophan from Mexico
The synthetic racemic form of the essential amino acid tryptophan, explicitly listed under HTS 2933.99.1200 as an aromatic nitrogen heterocyclic compound. Used in nutritional supplements, animal feed, and pharmaceutical intermediates. Its indole ring structure qualifies it for this specific subcategory.
Duty Rate — Mexico → United States
110%
Rate breakdown
9903.04.6094.2%Except as provided in heading 9903.04.61, patented pharmaceutical articles as provided for in subdivisions (c) and (d) of U.S. note 40 to this subchapter
9903.05.5510%Except for products described in headings 9903.05.85–9903.05.92 and 9903.05.94, articles the product of Mexico, as provided for in U.S. note 52 to this subchapter
Import Tips
• FDA prior notice required for food/feed grade tryptophan shipments
• Certificate of Analysis must specify optical rotation confirming dl-form
• Heavy metal and microbial testing documentation prevents FDA holds