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Thioglycolic Acid (Mercaptoacetic Acid) from Mexico

Thioglycolic acid (HSCH₂COOH), also known as mercaptoacetic acid, is the prototypical organo-sulfur carboxylic acid classified under HTS 2930.90.4950. Features direct sulfur-carbon bonding meeting heading 2930 criteria; excluded from Chapter 32 coloring matters. Widely used in hair permanents, metal polishing, and chemical synthesis.

Duty Rate — Mexico → United States

100%

Rate breakdown

9903.04.6095.8%Pharmaceuticals Annex IV: patented pharma articles — 100% floor rate
9903.05.900%Articles already subject to Section 232 (steel/aluminum/copper + derivatives, autos + parts, wood, medium/heavy vehicles + parts, semiconductors, patented pharma) — U.S. note 52(f)

Import Tips

Include odorant/emetic documentation if added for safety per Chapter 29(g)

Certify <0.1% heavy metals content for cosmetic/pharma grade imports

Segregate 70% aqueous vs pure forms; different documentation requirements