HC Orange No. 1

What Is It?

HC Orange No. 1, which refers to Hair Colorant Orange No. 1, occurs as a dark orange, fine crystalline material. HC Orange No. 1 is used in the formulation of semi-permanent hair dyes, colors and tints.

Why Is It Used?

HC Orange No. 1 helps to impart color to hair. The exact color obtained will depend on the other ingredients that are used in the preparation and the starting color of the hair.

Scientific Facts

HC Orange No. 1 is used in semi-permanent hair coloring systems that are usually applied in a shampoo base and contain thickeners, alkalizers, and foam stabilizers. The color that is produced results from careful formulation of the product so that the ingredients interact in a highly controlled process.

Safety Information

The safety of HC Orange No. 1 has been assessed by the Cosmetic Ingredient Review (CIR) Expert Panel. The CIR Expert Panel evaluated the scientific data and concluded that HC Orange No. 1 was safe for use in hair dye formulations at concentrations up to 3.0%.

CIR Safety Review:

Skin penetration of HC Orange No. 1 was 1.28% at 24 hours. Acute oral exposure studies produced little toxicity, and short-term toxicity studies produced reduced body weight and increased liver and kidney weights after feeding of 0.5% HC Orange No. 1. There was no evidence of reproductive or developmental toxicity using concentrations up to 1.25% HC Orange No. 1 or in a multi-generation study in which 0.15% HC Orange No. 1 was painted on the skin.

While evidence suggests this ingredient is a mild ocular irritant, no skin irritation, sensitization, or photosensitization were seen in tests. The preponderance of data (four out of five studies) indicated that this ingredient was not genotoxic. Hepatocellular and parathyroid hyperplasia were noted in the dermal carcinogenicity study, but the overall findings were clearly negative.

Because the highest concentration tested that produced no significant sensitization in clinical tests was 3%, the CIR Expert Panel concluded that safety could be assured only at levels equal to or less than 3%.

More information about the safety of hair dyes

In Europe, HC Orange No. 1 is permitted for use in non-oxidative hair dye products at a maximum concentration of 1%. Please see Annex III for additional information concerning the use of HC Orange No. 1 in hair dye products marketed in Europe.

Link to the EU Cosmetic Regulation: http://europa.eu/legislation_summaries/consumers/product_labelling_and_packaging/co0013_en.htm

More Scientific Information

Hair dyeing formulations belong to three categories — temporary, semi-permanent and permanent coloring of hair. Temporary coloring preparations, often called color rinses, provide color which lasts until the first shampooing.

Ingredients which impart temporary color may have a fairly high molecular weight and are unable to penetrate the hair shaft. These materials are simply deposited onto the hair fiber and are removed by subsequent shampooing.

Semi-permanent coloring preparations generally provide color through several shampooings. These materials are often low molecular weight pre-formed dyes which can penetrate the hair shaft to some extent. HC Orange No. 1 is also known as 2-nitro-4′-hydroxydiphenylamine. HC Orange No. 1 functions as a hair colorant.


The FDA’s fact sheet on Hair Dye Products http://www.fda.gov/Cosmetics/ProductandIngredientSafety/ProductInformati…

Search the FDA Code of Federal Regulations http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/cfrsearch.cfm

EU Cosmetic Ingredients Inventory http://ec.europa.eu/consumers/cosmetics/cosing/