Facts about PPD and hair colorants
You may have read about a particular hair dye used in hair colorants called PPD (paraphenylenediamine or p-phenylenediamine).
The use of PPD is strictly regulated in the cosmetics safety legislation. PPD may only be used in hair colorants up to a certain level and products have to carry specific labelling instructions and warnings.
However, PPD is sometimes used illegally in so-called 'black henna' temporary tattoos - the sort that you might be offered at fairs and on the beach. You should always avoid these tattoos because PPD can be very harmful if applied direct to your skin in such high concentrations.