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Ethyl Methylphosphonic Acid (EMPA) from Mexico

Ethyl methylphosphonic acid (CH3P(O)(OH)(OC2H5)) is a hydrolysis product of nerve agents, featuring phosphorus bonded to one methyl group and one ethyl group with no additional carbon atoms. Classified under HTS 2930.90.9225 due to its specific phosphorus substitution pattern matching the heading description. Used in chemical analysis and degradation 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 NMR spectra confirming P-CH3 and P-OC2H5 bonds; critical for avoiding misclassification as general phosphonic acids

Comply with Chemical Weapons Convention import notifications; subject to enhanced scrutiny and end-use certificates

Label as research chemical only; commercial formulations may shift to pesticide classifications