Red flag
Evidence key Strong Moderate Weak How we grade
Cancer classification Scent ingredient Restricted in the EU Limited by IFRA
- What it can be used for
- Adds scent (the functions the EU ingredient database, CosIng, lists for it; a product may use it for any of them)
- CAS number
- 93-15-2
Why it’s flagged
Classified as a known or probable human carcinogen.
- IARC Group 2A (probably carcinogenic to humans). Source: IARC Monographs list of classifications
IARC Group 1 means carcinogenic to humans, Group 2A probably carcinogenic. EU Carc. 1A means known, 1B presumed to cause cancer in humans. These describe a hazard, not the risk at the amount in one product.
Used to add scent: its official function is perfuming or fragrance.
- Listed functions: fragrance, perfuming. Source: EU CosIng ingredient database
The EU ingredient database (CosIng) lists this ingredient's function as perfuming or fragrance, so it may be there to add scent, even on a label that never says “fragrance.”
Allowed in EU cosmetics only with limits.
- Annex III entry 102; products: (a) Fine fragrance; (b) Eau de toilette; (c) Fragrance cream; (d) Other leave-on products and oral products; (e) Rinse-off products; max (a) 0.01%; (b) 0.004%; (c) 0.002%; (d) 0.0002%; (e) 0.001%. Source: EU Cosmetics Regulation, Annex III (restricted)
Annex III (restricted substances) or Annex V (preservatives) of the EU Cosmetics Regulation sets maximum amounts, allowed product types or required warnings.
Use limited by the fragrance industry's own IFRA standard.
- IFRA standard “Methyl eugenol”: use limited. Source: IFRA Standards Library
IFRA, the fragrance industry's own standards body, sets maximum amounts for this material in different kinds of products.
What the research says
- Citronella oil, marketed as a natural insect repellent, has been banned in the European Union and Canada since 2006, partly because it contains methyl eugenol, which the US National Toxicology Program considers 'reasonably anticipated to be a human carcinogen' based on animal studies. Weak evidence. Ramsey 2020 (YJBM)
Each finding shows its evidence grade. See every graded fact or how we grade.
Don’t want it on you or in your air? Look for “fragrance-free,” not “unscented.” An unscented product can still contain a masking fragrance. Why the words matter.
What this page can’t tell you
These lists describe what a substance can do, its hazard. The risk from one product depends on how much is in it and how you use it, and the label doesn’t say how much.
Not being on a list doesn’t make an ingredient safe. It may never have been assessed.
“Fragrance” or “parfum” on a label can hide this ingredient and many others. In the US, the individual chemicals in a fragrance are rarely named on the label.
Check your products
Check a whole labelProducts that list itEWG Skin DeepShop fragrance-free
“Products that list it” opens Open Beauty Facts, a free database anyone can edit.
Flagged the same way
Official lists checked September 2026. Spotted a mistake? Tell us.