What it does
CosIng, the EU's cosmetic ingredient database, lists two functions for linalool: perfuming and deodorant.1 It is one of the most widely used fragrance substances. Market surveys reviewed by the EU's Scientific Committee on Consumer Safety (SCCS) found limonene and linalool to be the fragrance chemicals most commonly used in cosmetics, and one UK review found the two in 63% of 300 consumer products.2
Where it comes from
Linalool occurs in plants: together with linalyl acetate it is the main component of lavender oil.2 The SCCS describes it as common in scented cosmetics and in household products.2 Whether it arrives in a product through a plant oil or as a separate ingredient, the EU labelling rule treats it the same way.3
Why EU labels name it
Linalool has its own entry in Annex III of the EU cosmetics regulation, number 84: its presence must be indicated in the ingredient list when it exceeds 0.001% in leave-on products or 0.01% in rinse-off products.4 It was one of the 24 fragrance allergens on the list before the 2023 amendment added more.5
The entry sets no maximum amount.4 Its purpose is to let people who are already allergic to linalool find it on a label, because once someone is sensitised, a much lower concentration is enough to trigger symptoms.5
As a pure substance, linalool has an EU harmonised classification as a skin sensitiser, Skin Sens. 1B, with the hazard statement "May cause an allergic skin reaction".6 That classification describes the concentrated substance. For a finished cosmetic, the EU rule is the labelling above.
Oxidation: what sources say
Most of linalool's allergy story is about what happens after it meets air. The SCCS reports that its allergenicity is closely related to oxidation, and that the primary oxidation products, the hydroperoxides, are the main allergens.2
Patch tests bear this out. In a study in six countries, oxidised linalool prepared with a stable 1% content of linalool hydroperoxides gave positive reactions in 6.9% of 2,900 consecutive dermatitis patients, ranging from 3% to 13% between clinics. The authors describe pure linalool as not allergenic, or a very weak allergen.7 These were patients referred for patch testing, not the general population.
The SCCS adds that air oxidation can be limited to some extent by keeping air away from ingredients and finished products while they are handled and stored, and by suitable antioxidants.2
How it appears on a label
As Linalool, usually near the end of the list after Parfum, since the labelling thresholds are far below 1%. A lavender ingredient, which the 2023 rules name Lavandula Oil/Extract, can appear on the same list, and so can Linalyl Acetate, which has had its own allergen entry since 2023.5
If you know you react to linalool, its name is what to look for. A list that says only Parfum cannot confirm it is absent, because below the thresholds it need not be named. See EU fragrance allergen labels and fragrance free vs unscented.