The FDA banned safrole as a direct food additive due to carcinogenicity concerns, and its primary remaining legitimate uses are in certified research and forensic reference standard contexts. Any commercial import requires DEA registration and is subject to strict quantity and end-use controls.

All three are named at the HS6 level within the heterocyclic oxygen-heteroatom subchapter — safrole at 2932.94, isosafrole at 2932.91, and piperonal at 2932.93 — reflecting the HS Committee's decision to enumerate each controlled precursor separately. Correct identification of the specific compound is therefore essential to avoid misclassification among these closely related headings.