Hair Dye Allergies

About 5% of permanent hair dyes users develop allergy, mostly as an allergic contact dermatitis with redness and itching in the head area, but systemic reaction with involvement of the whole body skin and other organs may appear in severe cases (1). Hand dermatitis affects considerable percent of hair-dressers (2). The main cause is substance PPD.

PPD (4-ParaPhenyleneDiamine, C6H8N2)

PPD is widely present on the market since 1909 and it is still used in over 2/3 of permanent hair dyes. Commercial hair dye product typically comes in two bottles: the one with PPD based dye (non-oxidized and thus colorless) and the other with oxidizer or developer, usually hydrogen peroxide (H2O2). In the hair dying process initially the peroxide is used to break down the natural hair pigment melanin, then the PPD is used to replace melanin. When PPD reacts with peroxide it becomes partly oxidized and colored and it is this form which may cause allergy. Fully oxidized PPD does not cause allergy, so PPD sensitive persons can wear fur coats dyed with PPD safely (3). PPD can also be found in some dark colored cosmetics and temporary tattoos. In France, Germany and Sweden PPD was banned as a hair dye because it was thought to be too dangerous for health. (4).

Precautions needed:

Alternative names for PPD: PPDA, Orsinâ„¢, Rodolâ„¢, Ursolâ„¢.

Other hair dye substances which can cause allergy: 6-hydroxyindole, Isatin, p-Methylaminophenol (5).

Related substances to PPD which may also cause an allergic reaction: Azo groups (chemically: R-N=N-R) used in temporary hair dyes, ballpoint pen inks, gasoline and as coloring agent in foods and medications. Local anesthetics benzocaine and procaine, sulfa drugs, Para-aminobenzoic acid (PABA) in sun-protective creams, para-aminosalicylic acid used for tuberculosis.

Hair dyes producers misleadingly use some terms. “Hypoallergenic” hair dyes should less likely cause allergies, but this is not proven. “Fragrances free or unscented” only means the product has no odor, but this tells nothing about the risk for allergies. If a hair dye is completely “natural” it still doesn’t mean it can’t cause allergy.

Types of allergies caused by hair dyes

Allergic contact dermatitis (ACD) is an immunologic skin reaction that occurs in a genetically predisposed individual, the risk of sensitization rises with frequency of contacts with the allergen (6). A minimum of 10 days after initial use of PPD is required that an individual develops a specific sensitivity. On second and subsequent exposures to PPD an allergy reaction can develop in 6-72 hours (delayed hypersensitivity). In this process PPD molecule are destroyed by macrophages and cytotoxic T lymphocytes which histologically appear as a granuloma and it is clinically evident as a skin redness or rash and vesicles of various degrees. Affected areas are eyelids, rims of ears, skin at hair line, beard and are usually well demarcated but may propagate beyond the site of contact. Symptoms are itching or burning feeling.

Contact urticaria can develop in minutes to about 1 hour after exposure. Allergen (PPD) induces massive IgE antibodies production which leads to increased vascular permeability with skin redness and edema (swelling of eyelids). Contact Urticaria Syndrome (CUS) with red patches over the whole body skin and bronchial asthma with wheezing, sneezing, difficult swallowing an vomiting can appear.

Anaphylactic shock is extremely rare but its life threatening condition. Face oedema, grasping for air, blood pressure fall, rapid worsening of patient’s general state and fast death if not immediate help is available is usual sequence of events. It was reported that a 38 year mother died in UK in August 2000 shortly after changing her hair dye. She was asthmatic before and she firstly developed a nonspecific allergy with scalp itching after using her old hair dye for some months. After changing the dye anaphylactic shock developed and she died within an hour after applying it (7, 8 ).

Allergy Sensitivity Test

Consumer can apply a 20 cent sized spot of solution (i.e. dye and developer mixed together) behind the ear or the inner bend of the elbow for 48-72 hours. If no irritation or rash occurs during this time then the test is negative and the hair color may be considered as safe to use. If rash of a certain size (according to test scale) develops, this is a sign of allergy.

Dermatologist will use a patch test (9). A patch with a 2% PPD in petrolatum is applied to the upper back and checked after 48 hours. Negative reactions show no skin changes, positive can vary from a mild rash to prominent blisters or ulcers. With “ready-to-use” T.R.U.E. patch test 24 possible allergy causing substances (including PPD) are used (10).

Treatment of PPD Allergy

In acute severe cases of PPD hair dye dermatitis the hair and scalp has to be washed thoroughly with a mild shampoo. 2% hydrogen peroxide solution or compresses of potassium permanganate in a 1:5000 dilution has to be applied to completely oxidize the PPD. To soften the crust a wet dressing of olive oil and lime may be used.

The patch test has to be made afterwards to determine if there an allergy to PPD exists or there is “only” a common (non-allergic) contact dermatitis present. In the case of proved allergic dermatitis corticosteroid cream which diminish immune response can be applied.

Currently there are no permanent hair dyes that can be safely used by PPD allergic individuals.


Popular posts from this blog

Cheap Natural Dry Skin Care Tips For Dry And Damaged Skin

Women's Top 5 Health Concerns

Find a swimsuit that makes your hips look smaller