Ethyl Methylphosphonic Acid (EMPA) from Mexico
EMPA (CH3P(O)(OH)(OC2H5)) is a hydrolysis product of nerve agents, containing a phosphorus atom bonded to one methyl group, one ethoxy group, and one hydroxyl. Classified under HTS 2931.49.0055 due to the single methyl group on phosphorus with no additional carbon atoms beyond the ethyl substituent. Used in chemical analysis standards and decontamination studies.
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
• Submit certificates of analysis proving EMPA purity (>98%) and structural confirmation via mass spectrometry
• Declare any military or CBRN-related end-uses immediately; may require State Department or BIS licenses