92-44-4

Off white to redish white powder

2,3-Naphthalenediol is used in cosmetics asa component of oxidative hair dye. It is usedat a concentration of <0.1%.

ChEBI: Naphthalene-2,3-diol is a naphthalenediol.

2,3-Naphthalenediol shows low toxicity andmild irritant actions on the skin and eyes. Theoral LD50 value for rats of a 5% solutionin propylene glycol may be on the orderof 675 mg/kg (calculated by the method ofWeil). The intravenous LD50 value for miceis 56 mg/kg. At 1% concentration, it causedslight eye irritation in female albino rabbitsand exhibited erythemal response in guineapigs. At the 0.1% level (concentration in hairdye), it had no reaction on human skin. Thiscompound was nonmutagenic in Salmonellatyphimurium strain tests.
There is very little information in the literatureon the toxicity of 2,3-naphthalenediol.Assessment by the CIR expert panel on thesafety of this compound as used in cosmeticshas been inconclusive (Cosmetic, Toiletryand Fragrance Association 1987b).

2,3-Dihydroxynaphthalene is prepared by caustic fusion of 3-hydroxynaphthalene-2,6-disulfonic acid followed by treatment with dilute sulfuric acid under pressure, or by acid desulfonation of 2,3-dihydroxynaphthalene-6-sulfonic acid.