Sodium Sulfate

What Is It?

Sodium Sulfate is an inorganic salt. In cosmetics and personal care products, Sodium Sulfate is used in the formulation of cleansers, bath soaps and detergents, and skin care preparations.

Why Is It Used?

Sodium Sulfate increases the thickness of the aqueous (water) portion of the finished product.

Scientific Facts

Sodium Sulfate occurs naturally as the minerals mirabilite and thenardite.

Safety Information

The Food and Drug Administration (FDA) reviewed the safety of Sodium Sulfate and determined that it was Generally Recognized As Safe (GRAS) for use as an indirect food additive. The safety of Sodium Sulfate has been assessed by the Cosmetic Ingredient Review (CIR) Expert Panel. The CIR Expert Panel evaluated the scientific data and concluded that Sodium Sulfate was safe in rinse-off formulations, and safe with limits in leave-on formulations.

CIR Safety Review:

In assessing the safety of Sodium Sulfate, the CIR Expert Panel relied on its GRAS status to preclude the need for many studies. Further, the submission of dermal irritation and sensitization data addressed the CIR Expert Panel’s concerns about the lack of such studies in the published literature. The CIR Expert Panel decided that these data were sufficient to conclude that Sodium Sulfate was safe as used in rinse-off formulations. However, because some of these formulations produced irritation under patch test conditions, the CIR Expert Panel restricted the use of Sodium Sulfate in leave-on products to 1%.


Link to Code of Federal Regulations for Sodium Sulfate…

Sodium Sulfate may be used in cosmetic 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:

The Joint FAO/WHO Expert Committee on Food Additives has not found it necessary to limit the daily intake of Sodium Sulfate.

More Scientific Information

Sodium Sulfate, in the decahydrate form (includes 10 water molecules) and the anhydrous form (has no water molecules), is used as a viscosity increasing agent – aqueous in cosmetic products. Inorganic salts are the compounds formed when an inorganic base reacts with an inorganic acid. Under these circumstances, the base provides the cation while the anion is derived from the acid.


Find out more about the regulation of Food Additives by the Food and Drug Administration

Food Ingredients and Packaging:

Food Contact Substances:

Substances Generally Recognized As Safe (GRAS):

Search the Code of Federal Regulations

EU Cosmetics Inventory