About 7% of people with dermatitis had allergic reactions to oxidized linalool, a breakdown product of linalool (a common fragrance ingredient). The study found that while pure linalool is safe, it oxidizes when exposed to air, and those oxidized byproducts are what actually trigger allergies—meaning your fragrance exposure matters as much as the ingredient itself.

Researchers tested nearly 2,900 dermatitis patients across six countries (Denmark, UK, Singapore, Spain, Sweden, Australia) using a standardized patch test with oxidized linalool to see who reacted to it.

Funding not disclosed in abstract