Episode Details

Sassafras albidum smells exactly like root beer—bark, roots, twigs, leaves—and for 300 years it was more valuable than lumber or furs. But in 1960, the FDA banned the molecule that makes it taste like that: safrole. The twist? The flavor and the carcinogen are the same compound, so boiling doesn't help, and the tree is still thriving in North Carolina yards while homebrewing its replacement became the only legal path. 00:00:00 - A tree that smells like root beer 00:01:45 - The FDA ban in 1960 00:03:26 - Why you can't just boil out the toxin 00:05:01 - The unusual regulatory situation 00:06:42 - One law that broke everything 00:08:28 - Concentrated oil toxicity 00:11:44 - One molecule, three regulatory regimes 00:13:17 - The legal paths: banned bark tea, safrole-free extract, filé powder loophole 00:14:52 - The actual tree is in trouble 00:18:05 - The soul is still in the ground --- Sources & further reading: • Long EL, Nelson AA, Fitzhugh OG, Hansen WH — "Liver tumors produced in rats by feeding safrole" — Archives of Pathology 75: 595–604, 1963: https://jamanetwork.com/journals/jama/article-abstract/665379 • Ames BN, Magaw R, Gold LS — "Ranking possible carcinogenic hazards" — Science 236: 271–280, 1987: https://files.toxplanet.com/cpdb/pdfs/Science-Ranking.pdf • 21 CFR § 172.580 — "Safrole-free extract of sassafras": https://www.law.cornell.edu/cfr/text/21/172.580 • National Toxicology Program — "RoC Profile: Safrole": https://ntp.niehs.nih.gov/sites/default/files/ntp/roc/content/profiles/safrole.pdf • DEA Diversion Control Division — "Notice: Safrole and Sassafras Oil": https://www.deadiversion.usdoj.gov/chem_prog/advisories/safrole.html • DEA — "Safrole and Sassafras Oil Are Used in the Illicit Manufacture of MDMA" (April 2025 notice): https://www.deadiversion.usdoj.gov/chem_prog/advisories/docs/Safrole-Notice-Pink-4-30-25-FINAL.pdf • Virginia Native Plant Society — "The Spicebush Swallowtail Butterfly, Its Host Plants, and the New Threat They Face": https://vnps.org/the-spicebush-swallowtail-butterfly-its-host-plants-and-the-new-threat-they-face/ • Bates CA et al. — "Spread, Vector Flight Behavior, and Impact of Laurel Wilt in Sassafras Beyond the Gulf-Atlantic Coastal Plain" — Journal of Forestry 120(6): 633, 2022: https://academic.oup.com/jof/article/120/6/633/6581783 • Cameron RS et al. — "First report of laurel wilt disease caused by Raffaelea lauricola on sassafras in North Carolina" — USDA Forest Service Treesearch, 2018: https://research.fs.usda.gov/treesearch/57612 • NC Dept of Agriculture — "Deadly Laurel Wilt Disease Found in Sassafras for the First Time in N.C." — 2018: https://blog.ncagr.gov/2018/05/23/deadly-laurel-wilt-disease-found-in-sassafras-for-the-first-time-in-n-c/ • Moura DJ et al. — "A Computational Inter-Species Study on Safrole Phase I Metabolism-Dependent Bioactivation" — Molecules 28(3), 2023: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9962551/ • Wiseman RW et al. — "1′-Hydroxysafrole, a Proximate Carcinogenic Metabolite of Safrole" — Cancer Research 33: 590, 1973: https://aacrjournals.org/cancerres/article/33/3/590/479204 • Food Additives Amendment of 1958 (Delaney Clause) — Wikipedia: https://en.wikipedia.org/wiki/Food_Additives_Amendment_of_1958 • Cohen SM et al. — "How the 62-year old Delaney Clause continues to thwart science" — Regulatory Toxicology and Pharmacology, 2020: https://www.sciencedirect.com/science/article/pii/S0273230020301343 • FDLI — "Food Additive Reform: Time to Repeal the Delaney Clause?" — 2019: https://www.fdli.org/2019/02/food-additive-reform-time-to-repeal-the-delaney-clause/ • FoodPrint — "Real Food Encyclopedia: Sassafras and Filé": https://foodprint.org/real-food/sassafras-and-file/ • Wikipedia — "Filé powder": https://en.wikipedia.org/wiki/Fil%C3%A9_powder • Wikipedia — "Desire path": https://en.wikipedia.org/wiki/Desire_path • …and 4 more in the episode research notes This podcast episode was fully generated by AI — research, script, voices, and production. Bui