Ethyl Methanethiosulfonate from Mexico
Ethyl methanethiosulfonate is a synthetic organo-sulfur reagent used in protein chemistry for cysteine modification. It qualifies under HTS 2930.90.92.51 as an other organo-sulfur compound with S-C bonds, not covered by specific 2930 subheadings. Primarily employed in biochemical research and proteomics.
Duty Rate — Mexico → United States
13.7%
Rate breakdown
9903.05.5510%Section 301 (forced labor) — additional 10% ad valorem on products of Mexico
Import Tips
• Provide end-use statement for research vs. commercial to avoid dual-use scrutiny
• Ensure <0.1% heavy metal impurities per USP standards for lab reagent classification
• Package in amber glass with inert atmosphere; light-sensitive nature common inspection issue