While performing an overall work of toxicological assessment of hair dyes safety, the SCCS has released this memorandum on their sensitizing potential. The SCCS confirms that hair dye substances which fulfill the criteria for classification as skin sensitizers may not be safe for consumers, particularly so for hair dye substances categorized as extreme and strong sensitizers.
It was necessary to write the Memorandum as the assessment of the safety of hair dyes has been in terms of general toxicology rather than sensitization potential. Hence, "hair dye chemical X is safe for use at Y% in hair dyes intended for the consumer apart from its potential to cause skin sensitization".
Thus, the SCCS publishes an updated review of the sensitizing potency of the hair dye chemicals now evaluated, which should be, says the text, considered as indicative as evaluations are ongoing.
Substances classified as extreme sensitizers
• Toluene-2,5-diamine
• p-Phenylenediamine
• N-Phenyl-p-phenylenediamine
• 1,2,4-Trihydroxybenzene
• Dihydroxyindole
• 6-Hydroxyindole
• Isatin
• Basic Brown 17
• 4-Nitro-o-phenylenediamine
• HC Red n° 1
• HC Red n° 3
• 4-Amino-3-nitrophenol
• 3-Nitro-p-hydroxyethylaminophenol
• Indigofera tinctoria
Substances are classified as strong sensitizers
• Resorcinol
• m-Aminophenol
• 1-Naphthol
• 4-Amino-2-hydroxytoluene
• Phenyl methyl pyrazolone
• N,N-bis(2-Hydroxyethyl)-p-phenylenediamine sulfate
• 4-Amino-m-cresol
• 6-Amino-m-cresol
• Hydroxyethyl-p-phenylenediamine sulphate
• Hydroxyethyl-3,4-methylenedioxyaniline HCl
• 2,6-Dimethoxy-3,5-pyridinediamine HCl
• Hydroxypropyl bis (N-hydroxyethyl-p-phenylenediamine) HCl
• 6-Methoxy-2-methylamino-3-aminopyridine HCl
• 2,6-Diaminopyridine
• 1-Acetoxy-2-methoxynaphthalene
• 1-Hydroxyethyl-4,5-diamino pyrazole sulfate
• 2-Methyl-1-naphthol
• HC Red n° 7
• HC Violet n° 1
• HC Orange n° 2
• 2-Amino-6-chloro-4-nitrophenol
• Hydroxyanthroquinone aminopropyl methyl morpholinium …
