P-PHENYLENEDIAMINE SULFATE

Name / description

p-Phenylenediamine Sulphate; Benzene-1,4-diammonium Sulphate

---

Function(s) of this ingredient in cosmetic products

HAIR DYEING

Colours the hair

---

Occurrence in cosmetics

Oxidation hair colourant (permanent hair dyes)

---

Background information on use in cosmetics

Cosmetic hair dyes are subdivided according to different operating principles. There are temporary dyes (tints), semi-permanent dyes (semi-permanent hair colours) and permanent dyes (oxidation dyes or bleaches). Temporary dyes are characterised by the use of direct dyes (eg cationic dyes such as Basic Red 56 or Acid Blue 62). There is no chemical reaction with other components; the dyes adhere to the hair surface and last for one to two hair washes. For temporary hair dyes, azo, triphenylmethane or anthraquinone dyes are used. The temporary dyes are sold as aqueous alcoholic solutions. In combination with hairspray, it is also possible to apply very small golden or silver gloss pigments or even fluorescent substances to the hair. Semi-permanent dyes (tints) also use direct dyes (eg nitro dyes such as HC Blue 2 or HC Yellow 10). The hair is coloured circularly, which ensures that it lasts for eight to 10 hair washes. Nitro dyes diffuse because of their low molecular size into the hair but are washable. Other dyes which are used include nitrophenyl diamines, azo and quinonimine dyes in combination with organic solubilizers such as glycol ether or polypropylene. In the event of permanent dyes (oxidative hair dyes), colourless precursors, also referred to as developers and couplers, are first used. The actual dyes are formed through a chemical reaction. The entire hair is dyed and the colour is not washable.

---

Information on safe use

Hair colourants are at present amongst the most thoroughly examined cosmetic products on the EU market. Since 2003 the European Commission has pursued a global strategy for the safety assessment of hair colourants and hair dyes in Europe. More than 100 individual hair colourants were considered as safe by the Scientific Committee for Consumer Safety (SCCS) of the EU Commission after a comprehensive assessment and are allowed for use in Annex III of the EC Cosmetics Regulation. https://ec.europa.eu/health/scientific_committees/docs/citizens_hairdyes_en.pdf This substance is expressly approved and / or subject to a restriction as a result of an entry in Annex III of the EC Cosmetics Regulation after an assessment by the Scientific Committee on Consumer Safety of the EU Commission (SCCS). Restrictions can relate eg to purity criteria, a maximum concentration or the restriction to certain product categories. Subject to the conditions possibly imposed in Annex III, the use of this substance in cosmetic products is safe.

---

Why are we talking about it?

P-phenylenediamine (PPD) is accused of inducing allergies (sensitising). The facts: Existing data confirm the sensitising potential of PPD. However, the use of hair dyes has increased significantly, while the number of adverse reactions has remained stable. A better degree of purity of PPD and expertise in formulation have indeed made it possible to offer safer hair dyes. In addition, the concentration of PPD in hair dyes has been voluntarily lowered to the minimum by the manufacturers. Severe reactions can occur, but compared to the volumes of hair dye used, they are very rare. Nevertheless, because this risk is known, the use of hair products containing PPD must always be accompanied by strict conditions of use which are always duly mentioned on the packaging: - Hair dyes containing this substance must categorically be avoided if you have already had an allergic reaction, even a mild one, to PPD (as a subsequent one could be more severe). - Do not use if you have a henna tattoo: it is indeed recommended to be careful with temporary black henna tattoos, which may contain PPD and induce sensitisation and therefore potentially an adverse reaction to an ulterior hair dye. - It is recommended to systematically do a patch test 48 hours before the dye itself. If these conditions of use are not respected, in case of a reaction to a hair dye, it is recommended to consult an allergist in order to rule out an allergy to PPD. Last, professionals in contact with hair colouring products containing PPD should use gloves. Key points to take away: PPD is a known allergen, but the work done on the quality and formulation of the products allows for a safe use (except for the persons who are sensitive). Reactions can nevertheless occur, which is why it is imperative to respect the precautions for use indicated on the product. People who are allergic to PPD should of course avoid using dyes containing PPD.

---

Belongs to the following substance groups

---

Regulating cosmetics

Cosmetics Ingredients are subject to regulation. Please note, different regulations may apply to cosmetic ingredients outside the EU.