Expert Panel for Cosmetic Ingredient Safety:
The safety of 2,4-diaminophenol and 2,4-diaminophenol HCl has been assessed by the Expert Panel for Cosmetic Ingredient Safety. The Expert Panel evaluated the scientific data and concluded that 2,4-diaminophenol and 2,4-diaminophenol HCl were safe for use in hair dyes at concentrations up to 0.2% (as the free base).
2,4-Diaminophenol HCl was a skin and ocular irritant but did not induce sensitization. Dermal application of 2,4-diaminophenol was not carcinogenic and 2,4-diaminophenol HCl produced no evidence of carcinogenic activity in National Toxicology Program bioassays. On the basis of available data, and the use of the product as a colorant in oxidative hair dyes, the Expert Panel concluded that 2,4-diaminophenol and 2,4-diaminophenol HCl were safe for use in hair dyes at concentrations up to 0.2% (as the free base).
More information about the safety of hair dyes.
In the European Union, 2,4-diaminophenol and 2,4-diaminophenol HCl are not permitted for use in hair dye products (see Annex II).