Allergy to hair dye

doi:10.1136/bmj.39042.643206.BE

BMJ 2007;334:220 (3 February), doi:10.1136/bmj.39042.643206.BE

Editorials

Allergy to hair dye

Its incidence is rising, as more and younger people dye theirhair

The first 150 words of the full text of this article appear below.

For more than 100 years para-phenylenediamine(PPD) and other related members of the aromatic amine familyhave been the main agents used in permanent hair dyes, and morethan two thirds of hair dyes currently contain PPD. This compoundis an effective hair dye owing to its low molecular weight,its ability to penetrate the hair shaft and follicle, its strongprotein binding capacity, and its rapid polymerisation in thepresence of a coupler (a kind of catalyst) and an oxidisingagent. However these properties also make PPD an ideal contactallergen and, indeed, it is among the most potent.¹

During the 20th century allergic reactions toPPD became such a serious problem that it was banned from hairdyes in Germany, France, and Sweden.² Current European Unionlegislation allows PPD to comprise up to 6% of the constituentsof hair dyes on the consumer market (3% when added to . . . [Full text of this article]

John P McFadden, senior lecturer¹, Ian R White, consultant dermatologist¹, Peter J Frosch, director², Heidi Sosted, senior researcher³, Jenne D Johansen, director³, Torkil Menne, professor³

¹ St John's Institute of Dermatology, St Thomas' Hospital, London SE1 7EH, ² Department of Dermatology, Hautklinik Stadtische Kliniken, University of Witten/Herdecke, D-44137 Dortmund, Germany, ³ National Allergy Research Centre, Department of Dermatology, Gentofte Hospital, DK-2900 Hellerup, Denmark

john.mcfadden@kcl.ac.uk