Acetyl Hexamethyl Tetralin
Tonalide · AHTN
What it is
A synthetic polycyclic musk, chemically close to Galaxolide, used for its sweet musky scent in perfume, detergent, and fabric softener.
In this product: Fragrance and fixative. Adds musky depth and anchors lighter notes so the scent holds longer.
Dose & route, what actually matters
Like other polycyclic musks, the issue is persistence rather than a single dose. It resists breakdown, accumulates in fat and waterways, and shows up in human blood and breast milk with chronic use.
EUROPEAN UNION
Assessed by the EU SCCNFP, which classified it Category 3 (insufficient data) pending percutaneous absorption, phototoxicity, and organ-discoloration data. Not banned, monitored under REACH as an environmental concern.
UNITED STATES
No restriction. Hides inside “Fragrance” on US labels.
The evidence
The EU SCCNFP assessed AHTN (Tonalide) and classified it Category 3 (insufficient data), requiring further absorption, phototoxicity, and organ-discoloration data before a safety conclusion.
regulatory · 2000 · source
Tonalide is a persistent polycyclic musk repeatedly detected in human blood, breast milk, and adipose tissue, and assessed for persistent-bioaccumulative-toxic properties under REACH-aligned methodology.
review · 2022 · source
California Prop 65: Not listed.
How to avoid it
Scan for “Tonalide,” “AHTN,” or “Acetyl Hexamethyl Tetralin.” It is not yet individually labelled in the EU, so it still hides under “Parfum.” Fragrance-free or full-disclosure brands are the reliable route.
Editorial analysis of publicly available regulatory and peer-reviewed sources. Not medical advice. We name our evidence and link it, including when an ingredient is fine.