Fragrance allergy
This article has been translated from Finnish to English by Semantix. You can find the original article at the web adress https://www.kosmetiikka-allergia.fi/tietoa-kosmetiikasta/aurinkosuojavoiteetKirjaudu
We use perfumes merely for the pleasant scent that they give to our bodies. Fragrances are now also widely used in other cosmetic and household products from toothpaste to floor wax, as people prefer to use products that have a pleasant scent rather than completely unscented products. Fragrances without a particular scent are also used for odour masking, i.e. to cover an unpleasant distinctive smell of a product.
Fragrances
Fragrances used in products are combinations of natural scents and individual chemical compounds. Fragrances are highly volatile and fade away quickly. The fragrance industry uses more than 5,000 chemical scents and approximately 200 natural scents. The chemical structure of individual scents are well-known and clearly defined. They are either extracted from plants or made synthetically, and they have a simple and usually distinctive odour. Natural fragrances combine several chemicals, and a single fragrance may include hundreds of chemical compounds. Therefore, the natural fragrances are so full of nuances. Essential oils, which are made of fresh plant parts and sap, are one of the most important products among natural fragrances. Each perfume is a complex mixture of several natural fragrances and synthetic scents. Both fragrances and spices contain several same allergens, such as cinnamaldehyde and eugenol. Due to its anaesthetizing effect, eugenol is also used in dentistry.
Products that contain fragrances
Fragrances are found in almost all cosmetic and personal care products. Fragrances are added into shaving lotions, deodorants, skin creams, powders, cleansing milks, mascaras, lipsticks and other cosmetic products, sunscreen products, bath oils and foams, soaps, shampoos and other hair care products, toothpastes and mouthwashes. Synthetic scents are widely used in other household products as well. Almost all chemicals used at home, from detergents to cleaners and polishing agents, are scented.
Perfumes are usually made with fragrances mixed with alcohol, and the proportion of fragrances in the mixture is about 20–30%. In milder perfumes, such as cologne, the fragrance proportion is 4–5%, in soaps 1–2% and in cosmetic products usually 0.5%. Often a single fragrance is used to mask odours of a product, and only a very small amount, approximately 0.01 %, is used.
Symptoms of fragrance allergy
Most of the skin reactions caused by fragrances are due to allergic contact dermatitis, which is developed as a result of delayed hypersensitivity. Rash caused by a fragrance allergy is due to contact dermatitis which is triggered by a single or various fragrances coming in contact with the skin. Rash caused by the combined effect of fragrances and sunlight are rare. Fragrances can also trigger rhinitis and other respiratory symptoms to some people. Respiratory symptoms are not caused by allergic contact dermatitis but rather by irritant reaction.
The most common symptoms caused by fragrance allergy are skin symptoms in the face area (eye make-up, face creams, lipsticks), armpits (deodorants) and hands (hand creams, soaps). Rash in the eyelids or armpits is typically the first symptom. Eyelid rash can be caused not only by sensitivity to eye make-up or eye cream products but also to fragrances used in hair-cleansing products. Typical symptoms of a rash caused by fragrance allergy include red spots on the skin, itchy skin and, in a long term, dry and flaky skin. Eyelid rash often causes inflammation as well. On hands, the rash can cause blisters.
Diagnosis of fragrance allergy
Skin tests, i.e. patch tests, are used to identify the fragrances that cause allergic contact dermatitis. The regular patch test batteries used internationally include testing for different fragrance mixtures and balsam of Peru. Balsam of Peru is a natural substance which contains several other substances, and its use in cosmetics is forbidden. In approximately half of the fragrance allergy cases, balsam of Peru gives a positive result in patch tests. When allergy to cosmetics is suspected, a patch test can also be done with the products that caused the reaction. However, this kind of testing method does not always identify the fragrance allergy.
The suitability of a cosmetic product can also be evaluated by a user test. The evaluated substance is applied across a 2x2 cm skin area in the crook of the elbow or the inner part of the upper arm in the morning and evening for one week. If no rash occurs during the testing, the product is likely to be safe for a common use.
Fragrance allergy is increasing
The increased use of fragrances has also caused an increase in fragrance allergy cases over the last couple of decades. Several European and American studies have showed that fragrances are the most common substances in cosmetic and skin care products that cause allergic contact dermatitis. Four out of five patients have been female. According to a recent study conducted in Danish population, approximately 6% of the young adults are allergic to cosmetics. One third (2%) of the reactions was caused by fragrances in cosmetics, second third by preservatives and the last third by other substances contained by cosmetics. Of the customers who contacted the skin care and cosmetics information desk of Helsingin Allergia- ja Astmayhdistys, 33% had a fragrance allergy in 2017. The medical records of the general hospitals in Finland and the dermatology outpatient clinics of the Finnish Institute of Occupational Health showed that 6.9 % of the patients in 2000–2002 had a fragrance allergy. The most common allergens of the fragrance mixtures included oakmoss, isoeugenol and hydroxycitronellal. According to European studies, the allergic reactions caused by oakmoss have been increasing. Though its scent is considered ‘masculine’, half of the people who are currently allergic to it are female, which indicates that the substance is widely used also in cosmetics aimed at women.
Tips for dealing with fragrance allergy
Although a person with a fragrance allergy may get a reaction only from one or two fragrances, they may need to avoid the use of all scented products. The fragrance that triggers a reaction may be used as one of the components in several different types of products. However, there are many fragrance-free products available, including complete product lines from cosmetics to detergents. On the other hand, the so-called natural cosmetics usually contains a lot fragrances, and the natural cosmetics is actually a typical cause for fragrance allergy.
According to the current EU Cosmetics Directive, the packaging of cosmetic products must indicate all the product ingredients. However, it is not required to specify which fragrances have been used, and only the INCI name of ‘parfum’ or ‘aroma’ is used. The 26 fragrances that most commonly cause allergic reactions must be clearly identified in the list of ingredients of the product packaging.
Spices and food flavourings may contain the same allergens used in fragrances. It has been reported that some people with fragrance allergy have experienced symptoms in the mouth and even a rapid development of rash after eating spices. In practice, however, these cases are rare and limiting one’s diet is only recommended in special cases.
The most efficient way to prevent rash caused by fragrance allergy is to avoid the use of scented products. If the symptoms are mild, it is possible to use fragranced products depending on the condition of the skin. If rash still appears, mild hydrocortisone lotion will heal the rash fairly quick, but only if the substance that causes the reaction has been eliminated.
Revised in January 2018, original 2014
Kristiina Alanko, docent
dermatologist