Final Report on the Safety Assessment of Oxyquinoline and Oxyquinoline Sulfate
Oxyquinoline is a heterocyclic phenol which is used as a fungicide and bactericide in cosmetic formulations at concentrations at, or less than 1.0%. Oxyquinoline is metabolized and excreted in the urine as glucuronides. The acute oral LD50 toxicity in rats was 1.2 g/kg. In subchronic studies, no deaths occurred in male and female rats at 5 doses up to 12,000 ppm or in male and female mice up to doses of 6000 ppm. Solid 100% Oxyquinoline was mildly irritating to rabbit skin and a 100 mg dose of Oxyquinoline was only slightly irritating to the eye. No sensitization test data were available for either of these cosmetic ingredients. Oxyquinoline and Oxyquinoline Sulfate were mutagenic when assayed using the Ames procedure with metabolic activation. Mutagenic activity was also demonstrated in the mouse lymphoma assay. Oxyquinoline was noncarcinogenic in several oral rodent feeding studies. The data from this negative oral carcinogenic assay were judged to be insufficient to evaluate the safety of use of Oxyquinoline and Oxyquinoline Sulfate when cosmetic products containing these ingredients are applied to the skin. It is concluded that the available carcinogenicity and sensitization test data are insufficient to support a conclusion on the safety of Oxyquinoline and Oxyquinoline Sulfate as used in cosmetic products.