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Indole-3-Propionic Acid from China

Indole-3-propionic acid features a three-carbon carboxylic acid chain, under HTS 2933.99.0500 due to indole structure precedence. Used as neurotransmitter precursor and antioxidant.

Duty Rate — China → United States

12.5%

Rate breakdown

9903.05.3112.5%Section 301 (forced labor) — additional 12.5% ad valorem on products of China

Import Tips

Chain length variation doesn't affect indole classification

Water-soluble; verify dry powder vs solution form on import

Growing nutraceutical use; pure chemical stays Chapter 29