Gamma-Butyrolactone (GBL) from Mexico
Gamma-butyrolactone is a five-membered lactone ring (cyclic ester) with oxygen hetero-atom, used as solvent and precursor. Falls under HTS 2932.99.90 as other oxygen heterocycles, distinguished from excluded cyclic esters of polyhydric alcohols.
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
• DEA List I chemical; requires importer registration and advance notice per 21 CFR 1310
• Lactone structure verified by IR spectroscopy; distinguish from polymer grades