Common fragrance ingredients in shampoos and conditioners are frequent causes of eczema

March 27, 2009

Considerably more people than previously believed are allergic to the most common fragrance ingredient used in shampoos, conditioners and soap. A thesis presented at the Sahlgrenska Academy, University of Gothenburg, Sweden found that over 5% of those who underwent patch testing were allergic to the air oxidized form of the fragrance ingredient linalool.

"I would suspect that about 2% 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. Linalool is found in 60-80 percent of the perfumed hygiene products, washing up liquids and household cleaning agents that can be bought in the nearest supermarket, and it can be difficult for people who are allergic to avoid these products", says dermatologist Johanna Bråred Christensson, author of the thesis.

Around one person in five in Sweden has some form of contact allergy. Nickel is by far the most common substance that causes eczema, but the thesis shows that oxidized linalool occupies third place in the list, after nickel and cobalt.

In the study, oxidized linalool was added at patch testing for more than 3,000 patients who wanted to find out what was causing their eczema. Between 5% and 7% proved to be allergic to the oxidized form of the fragrance ingredient.

"Linalool is present in many products around us, and this is probably the reason that contact allergy to this material is so common. Some people can shower with shower cream that contains linalool but never develop contact allergy, but we know that the risk increases as the exposure to t! he substance increases", says Johanna Bråred Christensson.

Linalool is a fragrance ingredient found naturally in lavender, mint, and other plants. Linalool breaks down when it comes into contact with oxygen, it becomes oxidized and can cause allergy. Manufacturers do include other substances in the products to delay this oxidation process, but allergenic substances can st! ill be formed from linalool when it is stored.

"One way of trying to minimize exposure to oxidized linalool is to avoid buying large packs of soap and shower cream, and always to replace the top after using a bottle", says Johanna Bråred Christensson.!

EU legislation states that manufacturers must specify on the labels of hygiene products whether they contain linalool. Previous studies have shown that oxidized linalool may cause contact allergy in about 1% of patients with eczema.
-end-
BRIEF FACTS: COMMON CONTACT ALLERGENS

Around 10-15% of all Swedes are allergic to nickel, and this is the ! most common form of contact allergy. Another substance that may be present in imitation jewellery is cobalt, to which around 2 3% of the population is allergic. Linalool occupies third place in the list after nickel and cobalt. It has been estimated that 2% of all Swedes are allergic to linalool. Other substances that can cause contact allergy include various perfumes and preservatives.

The Sahlgrenska Academy

The Sahlgrenska Academy is the faculty of health sciences at the University of Gothenburg. Education and research are conducted within the fields of pharmacy, medicine, odontology and health care sciences. About 4000 undergraduate students and 1000 postgraduate students are enrolled at Sahlgrenska Academy. The staff is about 1500 persons. 850 of them are researchers and/or teachers.

This thesis is based on the following papers:

I. Air oxidation increases skin irritation from fragrance terpenes Bråred Christensson J, Forsström P, Wennberg A-M, Karlberg A-T, Matura M. Contact Dermatitis: 2009: 60: 32-40.

II. Oxidized linalool - a significant contact sensitizer Bråred Christensson J, Matura M, Gruvberger B, Bruze M, Karlberg A-T. Manuscript.

III. Hydroperoxides form specific antigens in contact allergy. Bråred Christensson J, Matura M, Bäcktorp C, Börje A, Nilsson JLG, Karlberg A-T. Contact Dermatitis: 2006; 55(4): 230-7.

IV. Limonene hydroperoxide analogues differ in allergenic activity. Bråred Christensson J, Johansson S, Hagvall L, Jonsson C, Börje A, Karlberg A-T. Contact Dermatitis: 2008; 59(6): 344-52.

University of Gothenburg

Related Eczema Articles from Brightsurf:

Vitamin D lessens symptoms of severe eczema in children
Vitamin D supplementation eased the symptoms experienced by children with severe atopic dermatitis, or eczema, in a recent randomized controlled trial published in Pharmacology Research & Perspectives.

TV ads for psoriasis and eczema medications portray few people of color
Commercials from pharmaceutical companies advertising medication to treat psoriasis and eczema lack people from racial and ethnic minorities, according to research from the Perelman School of Medicine at the University of Pennsylvania.

NIH-supported scientists demonstrate how genetic variations cause eczema
New research supported by the National Institutes of Health delineates how two relatively common variations in a gene called KIF3A are responsible for an impaired skin barrier that allows increased water loss from the skin, promoting the development of atopic dermatitis, commonly known as eczema.

Biomedical researchers get closer to why eczema happens
A new study from researchers at Binghamton University, State University of New York may help to peel back the layers of unhealthy skin -- at least metaphorically speaking -- and get closer to a cure.

Researchers uncover novel approach for treating eczema
Researchers at the University of British Columbia (UBC) and Vancouver Coastal Health Research Institute (VCHRI) have identified a key enzyme that contributes to eczema, which may lead to better treatment to prevent the skin disorder's debilitating effects.

Revving up immune system may help treat eczema
Studying eczema, researchers at Washington University School of Medicine in St.

Childhood eczema cannot be prevented by daily moisturiser use, study finds
Using moisturisers on newborn babies does not prevent eczema as previously thought, according to a major new study.

Atopic eczema linked to increase fracture risk in adults
Adults with atopic eczema could face a raised risk of fracture, with the risk increasing the more severe the condition, according to a new study published in the Journal of Allergy and Clinical Immunology.

Long-term dupilumab benefits adolescents with eczema
Results from a phase IIa open-label trial and a subsequent phase III open-label extension trial reinforce findings from an earlier short-term trial that adolescents with moderate-to-severe atopic dermatitis, or eczema, can experience significant improvements with dupilumab.

Multiple genes affect risk of asthma, hay fever and eczema
In a new study from SciLifeLab at Uppsala University, researchers have found a total of 141 regions (genes) in our genetic material that largely explain the genetic risk underlying asthma, hay fever and eczema.

Read More: Eczema News and Eczema Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.