Study questions potential fragrance allergen not currently declared in cosmetics

Linalyl acetate, a fragrance chemical that is one of the main constituents of the essential oil of lavender, may be an emerging fragrance allergen and should appear in the declaration of ingredients for cosmetics, according to a study by the University of Gothenburg, which suggests that it can cause allergic eczema.

As it stands, the chemical is not on the list of allergenic compounds pursuant to the EU Cosmetics Directive, meaning it does not need to be declared on cosmetic products sold within the EU.

In accordance with the EU Cosmetics Directive, make-up, ointments, shampoo, deodorants, toothpaste and other products must contain a declaration of ingredients in order for consumers to avoid the substances to which they are allergic.

Products sold in the EU are safe thanks to strict guidelines; however new studies at Sahlgrenska Academy have found that linalyl acetate can react with oxygen in the air to form strongly allergenic hydroperoxides, which could mean it may be a common cause of contact allergy.

The study, ‘Air-oxidized linalyl acetate – An emerging fragrance allergen?’ has been published in Contact Dermatitis, and suggest that the substance is mildly allergenic and should be included in the declaration of ingredients for cosmetic products.

This is because at present it could be difficult for consumers to try and avoid the substance as it is not currently highlighted in products.

Study

The study assessed 1,717 subjects for eczema related to contact allergy, and found that approximately 2% of them had allergic reactions to oxidized linalyl acetate.

"That may seem like a small percentage," says Lina Hagvall, a researcher at the University of Gothenburg. "But it is approximately the same result as for the fragrance compounds listed in the Cosmetics Directive."

The subjects who reacted to oxidized linalyl acetate were also exposed to other fragrance compounds that are part of routine testing these days, and a total of 57% of them had no allergic reaction.

"The trials suggest that a broad range of tests is required to detect contact allergies to fragrance compounds," continues Dr Hagvall. "Current tests do not identify the majority of people who have contact allergy to oxidized linalyl acetate.”

According to the researchers, the study findings should lead to inclusion of oxidized linalyl acetate among the fragrance compounds used for diagnosis of contact allergy and it should also appear in the declaration of ingredients for cosmetic products.