Isopropyl Methylphosphonic Acid (IMPA) from Canada
IMPA contains a phosphorus atom bonded to one methyl group and one isopropoxy group (P-CH3, P-O-CH(CH3)2). Fits HTS 2931.49.0055 as the phosphorus has one isopropyl group allowed by the heading description with no further carbon atoms in the chain. Marker compound for chemical weapons verification.
Duty Rate — Canada → United States
100%
Rate breakdown
9903.04.6096.3%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 OPCW or laboratory certification for legitimate analytical use to avoid security delays
• Test for impurities that could trigger reclassification to pesticide headings (3808)
• Store and ship as corrosive solid; verify temperature control for stability