- What it can be used for
- Adds scent and stops foaming (the functions the EU ingredient database, CosIng, lists for it; a product may use it for any of them)
- CAS number
- 80-56-8
Why it’s flagged
A fragrance allergen the EU requires companies to name on the label.
- Annex III entry 371; 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”.
What the research says
- Scent-type chemicals typical of fragranced and cleaning products (limonene, pinene, carene) were the signature of home air: close to zero outdoors but tens to hundreds of times higher inside homes. Strong evidence. Gokhale 2008
- In week-long air measurements across 11 European cities, the scent chemicals limonene and alpha-pinene were the compounds most concentrated in homes compared with workplaces (about 4x), attributed to perfumes, cleaning and fragranced products. Strong evidence. Geiss 2011
- Even in Perth, a city with very clean outdoor air, limonene and pinene (scent chemicals typical of citrus- and pine-scented cleaners and air fresheners) were found in 80-100% of homes when a sensitive test was used. Strong evidence. Maisey 2013
- A 1991 US EPA survey of 31 fragrance products already found limonene, linalool, alpha-pinene, benzyl acetate, benzyl alcohol, camphor and acetone among the most common chemicals, the same compounds found in fragranced products tested in the 2010s. Moderate evidence. DONTSPRAYCALIFORNIA 2008 (DOJ ADA docket)
- A car air freshener's own terpenes (alpha-pinene, beta-pinene, p-cymene, limonene) react with in-vehicle ozone to form ultrafine particles and irritant gases (formaldehyde, acetaldehyde, acrolein) that never appear on the product's ingredient list, because they are made in the cabin air, not sold in the bottle. Moderate evidence. Lamorena & Lee 2008 (J Hazard Mater)
- In a study of 25 UK homes using real whole-air canister sampling (not a lab chamber), the scent chemicals D-limonene and alpha-pinene were the single most abundant VOC measured in 94% of homes, regardless of building age, size or occupancy. Moderate evidence. Wang 2017
- Plug-in and hanging car air fresheners mainly release fragrance terpenes (limonene, pinene, dihydromyrcenol) and fruity-smelling esters, the same terpenes found across larger product surveys. Moderate evidence. Pino-Delgado 2021; Steinemann 2011
- In the nasal-lavage arm of the same 130-woman chamber study, breathing a VOC-ozone mixture containing citrus and pine scent chemicals (limonene, alpha-pinene) caused no significant increase in nasal irritation symptoms or in objective inflammation markers (immune cells, IL-6, IL-8, protein) in nasal fluid. Moderate evidence. Laumbach 2005
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.