Sodium Naphthalenesulfonate

What Is It?

In cosmetics and personal care products, Sodium Polynaphthalenesulfonate and Sodium Naphthalenesulfonate are used in the formulation of makeup preparations including eyeshadow, mascara, blushers, foundations and lipstick.

Why Is It Used?

Sodium Polynaphthalenesulfonate and Sodium Naphthalenesulfonate enhance the water solubility of other cosmetic ingredients and help to distribute or to suspend an insoluble solid in a liquid. Sodium Polynaphthalenesulfonate also helps to keep the final product from separating into its oil and water components.

Scientific Facts

Sodium Polynaphthalenesulfonate and Sodium Naphthalenesulfonate are sodium salts of naphthalene sulfonic acid. Sodium Polynaphthalenesulfonate is used as an emulsion stabilizer, surfactant – hydrotrope, and/or surfactant – suspending agent.

Hydrotropes are surfactants which have the ability to enhance the water solubility of another surfactant. Prominent members of this group are short chain alkyl aryl sulfonates, sulfosuccinates, and some nonionic surfactants. Sodium Naphthalenesulfonate is used as a surfactant – hydrotrope.

Safety Information

The safety of Sodium Polynaphthalenesulfonate and Sodium Naphthalenesulfonate has been assessed by the Cosmetic Ingredient Review (CIR) Expert Panel. The CIR Expert Panel evaluated the scientific data and concluded that Sodium Polynaphthalenesulfonate and Sodium Naphthalenesulfonate were safe in cosmetic formulations intended to be applied to the skin.

The available data, however, were insufficient to support the safety for use of these ingredients in cosmetic products which may contact mucous membranes or be ingested.

CIR Safety Review: The CIR Expert Panel received data on Sodium Naphthalenesulfonate, including skin penetration data and complete study reports on ocular toxicity and dermal irritation and sensitization, mutagenesis studies and clinical tests.

In assessing the information, the CIR Expert Panel considered the low skin penetration and the low concentrations of use of these ingredients and the absence of significant overall toxicity; and the available negative genotoxicity findings were sufficient to support a conclusion that Sodium Naphthalenesulfonate and Sodium Polynaphthalenesulfonate were safe as used in cosmetic formulations intended to be applied to the skin (external applications).

The CIR Expert Panel took into account that the barrier properties of the skin do no apply when these ingredients contact mucous membranes or are ingested. Accordingly, the CIR Expert Panel concluded that the available data were insufficient to support the safety of Sodium Naphthalenesulfonate and Sodium Polynaphthalene Sulfonate in cosmetic formulations that may contact mucous membranes or be ingested. The residue level of formaldehyde in Sodium Polynaphthalenesulfonate is 0.09%, below the 0.2% limit for free formaldehyde established earlier by the CIR Expert Panel.

More information about formaldehyde.

Sodium Naphthalene Sulfonate and Sodium Polynaphthalene Sulfonate may be used in cosmetics and personal care products marketed in Europe according to the general provisions of the Cosmetics Regulation of the European Union.

Link to the EU Cosmetic Regulation: 
http://europa.eu/legislation_summaries/consumers/product_labelling_and_p…

More Scientific Information

Sodium Polynaphthalenesulfonate is the sodium salt of the product obtained by the condensation polymerization of naphthalene sulfonic acid and formaldehyde. Sodium Polynaphthalenesulfonate functions as an emulsion stabilizer, surfactant – hydrotrope, and/or surfactant – suspending agent).

Sodium Naphthalenesulfonate is the sodium salt of naphthalene sulfonic acid. It functions as a surfatant- hydrotrope.