What Is It?
Oxyquinoline occurs as a white powder or crystals, whereas Oxyquinoline Sulfate occurs as a pale yellow crystalline powder. Oxyquinoline and Oxyquinoline Sulfate are used in the formulation of hair dye products.
Why Is It Used?
Oxyquinoline and Oxyquinoline Sulfate function as chelators. By binding trace metals, hydrogen peroxide used in hair care product (including hair dyes) is stabilized.
Oxyquinoline and Oxyquinoline Sulfate have antimicrobial activity and in some countries may be used as topical anti-infective agents.
The safety of Oxyquinoline and Oxyquinoline Sulfate has been assessed by the The Cosmetic Ingredient Review (CIR) was established in 1976 as an independent safety review program for cosmetic ingredients. The CIR Expert Panel consists of independent experts in dermatology, toxicology, pharmacolgy and veterinary medicine. The CIR includes participation by the U.S. Food & Drug Administration and the Consumer Federation of America. (CIR) Expert Panel. The CIR Expert Panel evaluated the scientific data and concluded that Oxyquinoline and Oxyquinoline Sulfate were safe as used as stabilizers for hydrogen peroxide in rinse-off hair care products. The data were insufficient to determine the safety of Oxyquinoline and Oxyquinoline Sulfate in leave-on cosmetics and personal care products.
CIR Safety Review: Oxyquinoline was metabolized and excreted in the urine as glucuronides. These ingredients exhibited little acute or subchronic toxicity. A 100 mg dose of Oxyquinoline was only slightly irritating to the eye. Oxyquinoline and Oxyquinoline Sulfate were genotoxic in certain Salmonella typhimirium strains with metabolic activation and in a lymphoma assay. No genotoxicity was found in a fruit fly sex-linked recessive lethal test, bone marrow micronucleus test, a bone marrow and hepatocyte micronucleus test, unscheduled DNA synthesis in hepatocytes, and chromosome aberrations and sister-chromatid exchanges in hepatocytes. Oxyquinoline was non-carcinogenic in several feeding studies, and newly available studies including one with the human c-Ha-ras gene, demonstrated that Oxyquinoline was not carcinogenic. In clinical tests, Oxyquinoline was neither an irritant nor a sensitizer when tested at 1% in petrolatum.
The available data demonstrated that Oxyquinoline and Oxyquinoline Sulfate as stabilizers for hydrogen peroxide in rinse-off hair care products were safe in the present practices of use. The CIR Expert Panel requested additional information on UV absorption and phototoxicity data to assess the safety for leave-on cosmetics and personal care products.
More information about the safety of hair dyes.
Health Canada permits the use of Oxyquinoline and Oxyquinoline Sulfate (8-Hydroxyquinoline and its sulfate salt) as stabilizers for hydrogen peroxide in rinse-off and leave-on hair care products at concentrations equal to or less than 0.3% and 0.03%, respectively.
Oxyquinoline and Oxyquinoline Sulfate are listed as Hydroxy-8-quinoline and its sulfate in the Cosmetics Directive of the European Union (see Annex III) and may be used as stabilizers for hydrogen peroxide in rinse-off and non-rinse-off hair care products at a maximum concentration of 0.3% and 0.03%, respectively. As indicated in Annex II, these ingredients may not be used in any other manner in cosmetics and personal care products in the European Union.
Link to the EU Cosmetic Regulation:
More Scientific Information
Oxyquinoline is a heterocyclic phenol amine and Oxyquinoline Sulfate is its salt. In hair products containing hydrogen peroxide, these ingredients function as chelators. Binding trace levels of metals that may be present helps stabilize the hydrogen peroxide.
Search the Code of Federal Regulations http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/cfrsearch.cfm
EU Cosmetics Inventory http://ec.europa.eu/consumers/cosmetics/cosing/