Picramic Acid

What Is It?

Picramic Acid is a dark red crystalline material. Sodium Picramate is the sodium salt of Picramic Acid. Both Picramic Acid and Sodium Picramate may be used as dyes in in permanent hair dyes and colors.

Why Is It Used?

Picramic Acid and Sodium Picramate 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

Picramic Acid and Sodium Picramate are used in permanent hair coloring systems where color is produced inside the hair fiber. This is accomplished through careful formulation of the product so that the ingredients interact in a highly controlled process.

Safety Information

The safety of Picramic Acid and Sodium Picramate has been assessed by the Cosmetic Ingredient Review (CIR) Expert Panel. The CIR Expert Panel evaluated the scientific data and concluded that Picramic Acid and Sodium Picramate were safe as hair dye ingredients at reported use concentrations.

CIR Safety Review:

The CIR Expert Panel reviewed the safety of Picramic ACcid and Sodium Picramate as they are use in hair dye products. When included in a hair dye formulation, very little skin absorption of Picramic Acid was observed. Sodium Picramate was mutagenic in bacteria but not non -mutagenic in mouse cells in vitro. An oxidative hair dye containing Picramic Acid applied weekly was non-carcinogenic. A hair dye containing Picramic Acid did not cause developmental effects when applied dermally . The CIR Expert Panel noted that Picramic Acid and Sodium Picramate are sensitizers and some persons may be sensitized under intended conditions of use.

The CIR Expert Panel expects that following label instructions on hair dye products will identify persons with irritation and sensitization reactions and allow them to avoid significant exposure. On the basis of the available data, the CIR Expert Panel concluded that Picramic Acid and Sodium Picramate were safe as hair dye ingredients at reported use concentrations.

More information about the safety of hair dyes.

Picarmic Acid and Sodium Picramate are not specifically listed in the Cosmetics Directive of the European Union.

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

Sodium Picramate may be used in hair dyes marketed in Canada at concentrations less than or equal to 0.1%.

Link to the Canada Hot List http://www.hc-sc.gc.ca/cps-spc/person/cosmet/info-ind-prof/_hot-list-cri…

More Scientific Information

Hair dyeing formulations belong to three categories – temporary, semi-permanent and permanent coloring of hair. The permanent hair dyeing formulations are often referred to as oxidative hair dyes which are generally marketed as two-component products.

One component contains the compounds (precursors) that become the colorants and the other component is a stabilized solution of hydrogen peroxide. The two components are mixed immediately prior to use.

The precursors and peroxide diffuse into the hair shaft, where color formation takes place after the ingredients combine to produce the coloring mixture. The precursors are oxidized by the hydrogen peroxide to form the colorant molecules.

These molecules are too large to escape from the hair structure. The hydrogen peroxide in the oxidative hair dye product also serves as bleaching agent for the natural pigment of the hair. The color that is formed depends on the precursors and direct dyes present in the dyeing solution, pH of the dyeing solution and the time of contact of the dyeing solution with the hair as well as the starting color of the hair being dyed. Picramic Acid is also called 2-amino-4,6-dinitrophenol. Sodium Picramate is the sodium salt of 2-amino-4,6-dinitrophenol.