Description
HYDROQUINONE is an aromatic organic compound, according to the official chemical description. Its chemical name, 1,4-dihydroxybenzene, denotes a benzene ring with two hydroxyl groups at positions 1 and 4. The CosIng entry assigns it the technical functions of antioxidant, bleaching agent, hair dye, fragrance component and reducing agent. In general terms, antioxidants are used in cosmetics to delay oxidation processes in the formulation; reducing agents take part in chemical reactions of the system; hair dyes impart color to the hair; bleaching agents act on the color of substrates; and fragrance components contribute to the olfactory profile.
The substance appears in Annex II, reference 1339, of Regulation (EC) No 1223/2009 as a generally prohibited component, with the literal clause "with the exception of entry 14 in Annex III". That exception corresponds to Annex III, reference 14, which authorizes its use exclusively in artificial nail systems ("Artificial nail systems") at a maximum concentration of "0.02% (after mixing for use)" and under the condition of "Professional use". The mandatory labelling warnings, according to the entry itself, are "For professional use only", "Avoid skin contact" and "Read directions for use carefully". The CosIng entry also records a CMR classification: Carcinogenic Cat. 2 and Mutagenic Cat. 2.
In cosmetic formulations, antioxidants are used to delay oxidation processes in the formulation; reducing agents take part in chemical reactions of the system; hair dyes impart color to the hair; and components with a fragrance function contribute to the olfactory profile of the finished product. The information presented is for technical reference only and does not constitute a recommendation for use or an efficacy claim.