Hair Dyes and Contact Dermatitis - Toxic Beauty

Severe cases of facial and scalp dermatitis have been reported through the application of permanent hair dyes. Chemical solutions used to highlight hair can corrode the scalp in some cases.

One incredibly potent cause of allergic contact dermatitis in humans is a hair colourant called paraphenylenediamine (PPD), also referred to as p-phenylenediamine, used in permanent hair dyes. This substance was prohibited for use in hair dyes in Germany, France and Sweden in the 2oth century, because concerns developed about its damaging health effects.

PPD is not approved for direct application to the skin, yet when hair dye is applied it usually does come in contact with the scalp and very often the forehead and ears. According to Dr John P McFadden, senior lecturer at St John's Institute of Dermatology, patients with contact allergies to hair dyes often have dermatitis around the face or hairline and sometimes facial swelling is so severe that the patients must be hospitalized.

He also highlights the growing number of individuals suffering allergic reactions to PPD in patch tests. A survey of one London contact dermatitis clinic, where eczema patients were patch tested for reactions to PPD, found that allergy to the substance had almost doubled from 4.2 percent in January 1999 to 7.1 percent in December 2004.

The study authors state the 'disturbing' increase in positive reactions to PPD over the six-year period where research took place 'may be due to subjects dyeing their hair in increasing numbers and perhaps at an earlier age'.

Patch testing data from other countries such as Belgium, Portugal, Denmark, Germany and Singapore support this pattern. Dr McFadden writes in the British medical Journal that more than one million Thai adults and 1.3million adults in Germany may become sensitive to PPD.

Of those individuals who are allergic to PPD, 10 per cent also react to semi-permanent hair dyes. Those who may have sensitivity to PPD may also develop cross-sensitivity to azo and aniline dyes ( used in hair dyes, ballpoint pen inks, petrol, diesel oil and as a colorant in foods and medications), benzocaine and procaine (used in local anaesthetics), para-aminobenzoic acid (PABA) = used in sunscreens and some face creams), para-aminosalicylic acid (used in tuberculosis treatment) sulphonamides (used in pharmaceutical drugs), carbutamide (used in diabetes medication) and hydrodiuril (a diuretic medication).

According to Scientific Committee on Consumer Products (SCCP) PPD sensitizes 100 per cent of laboratory animals used in predictive allergenicity testing at high enough concentrations. When one particular study advertised for individuals suffering from adverse reactions to hair dye, 55 people with severe allergic contact dermatitis came forward.

In some cases swelling of the scalp, ears and face were so acute that the people were originally treated for angio-oedema (allergic reaction causing swellings beneath the skin) and some had had to be admitted in to hospital.

The study concluded that this substance presents a significant health risk for the population, yet it is authorized in hair dyes in concentrations of up to 6 percent in the EU and 4 percent in the US.

DID YOU KNOW?

Abrasive substances are used in exfoliants, such as talc, fruit pits, crushed nutshells and aluminium oxide (in the case of microdermabrasion) to soften or remove the stratum corneum.

The International Dermal Institute 'do not recommend the use of crushed fruit pits, shells or similar damaging substrates', due to their ability to cause skin irritation.

Dr Sandy Tsao, an instructor of dermatology at Harvard Medical School, points out that removing the stratum corneum leaves the skin vulnerable to sunburn, wrinkles, age spots and cancerous legions. Aggressively rubbing exfoliating products onto the skin can cause broken capillaries and tiny skin fissures.

Reference: Toxic Beauty: Dawn Fellowship