Scientists claim fragrance and hair care ingredients cause eczema

In a thesis presented at the Sahigrenska Academy patch tests purportedly showed that over 5 percent of those who had the test were allergic to the fragrance ingredient linalool, which was oxidized to simulate normal use.

In the study 3,000 patients already suffering from allergy-induced skin conditions were given an oxidized linalool patch, with the results showing that between 5 – 7 percent of individuals showed a distinct allergic reaction to the substance.

Linalool is derived from flowers and spice plants and is used to fragrance a broad spectrum of household consumer goods, from personal care products such as soaps and shampoos through to a range of household cleaning products.

Linalool is ubiquitous​

Johanna Bråred Christensson, dermatologist and author of the thesis says that Linalool is found in 60 – 80 percent of perfumed hygiene products, making it difficult to avoid for individuals suffering from the allergy.

"I would suspect that about 2 percent of the complete population of Sweden are allergic to air oxidized linalool. That may not sound very much, but it is serious since linalool is so widely used as a fragrance ingredient,”​ she said.

Previous studies on contact allergies have tended to highlight the effects of Nickel and Cobalt on contact allergies and have in turn drawn links with the incidence of eczema and other related skin conditions.

One in five suffer contact allergies​

Indeed, the widespread use of these products in a variety of consumer products is thought to account for allergic contact allergies in an estimated one in five of the population in Sweden.

However, neither Nickel or Cobalt is commonly used in personal care formulations.

Christensson believes that the results of her study indicates that Linalool rates as the third most likely chemical to induce an allergic skin reaction in humans, behind Nickel and Cobalt respectively.

Linalool has been cited as a moderate to frequent allergen and EU regulations require that any product containing it should specify that approximately 1 percent of users are likely to have an allergic reaction to it.

Linalool was last reviewed by the US Environmental Protection Agence in April 2007, when it was determined that there was no ‘clear indication that linalool was the only possible cause of adverse effects’.