Methanesulfinic Acid Sodium Salt from Mexico
Sodium methanesulfinate (CH₃S(O)ONa) is the sodium salt of methanesulfinic acid, classified under HTS 2930.90.4950 per Chapter 29 note 4(C)(1). Contains sulfur directly linked to carbon via sulfinic acid function; distinguished from sulfonic acids. Used as reducing agent in organic 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
• Submit counterion analysis confirming sodium content per salt classification rules
• Include oxidation state confirmation (S(IV) vs S(VI) sulfonic acids)
• Hygroscopic; specify moisture content <5% in COA