Worth a closer look
Evidence key Strong Moderate Weak How we grade
Labeled fragrance allergen (EU) Scent ingredient Limited by IFRA
- What it can be used for
- Adds flavor, adds scent and makes alcohol undrinkable (the functions the EU ingredient database, CosIng, lists for it; a product may use it for any of them)
- CAS number
- 100-52-7
Why it’s flagged
A fragrance allergen the EU requires companies to name on the label.
- Annex III entry 330; on labels from 2026 to 2028 (Regulation 2023/1545). Source: EU Cosmetics Regulation, Annex III (restricted)
Must be named on EU labels above 0.001% in leave-on and 0.01% in rinse-off products. Elsewhere, including the US, it can hide inside “fragrance”.
Used to add scent: its official function is perfuming or fragrance.
- Listed functions: denaturant, flavoring, 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.”
Use limited by the fragrance industry's own IFRA standard.
- IFRA standard “Benzaldehyde”: 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
- In 1999 a dermatologist listed ten US "fragrance-free" skin products that named fragrance chemicals in their own ingredient lists, including a "fragrance-free" cleansing bar containing rose, rosewood, cedarwood and almond oils; one manufacturer admitted the benzaldehyde in its fragrance-free product was there to mask an unpleasant smell. Moderate evidence. Scheinman 1999
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.