Final Report on the Safety Assessment of Stearalkonium Chloride

Abstract

Stearalkonium Chloride is a cationic quaternary ammonium salt used in cosmetic products at concentrations of ≤0.1 to 5%. It is used in cosmetics predominantly for its surfactant and antimicrobial properties. Studies have failed to establish with certainty the oral LD50 in rats of Stearalkonium Chloride, the value falling between 0.5 and 1.25 g/kg. In mice, an LD50 value of 0.760-0.113 g/kg was reported in a seven-day oral study. Single application dermal studies with concentrations of up to 25% have shown Stearalkonium Chloride to produce minor irritation in rabbits. Acute eye studies in rabbits have shown a 25% solution of the material to be a severe irritant. Concentrations of 1.25% and less are slightly and transiently irritating to the rabbit eye. A repeated insult patch test with a 1% aqueous solution of Stearalkonium Chloride on 50 subjects showed the material to be neither a primary irritant nor a sensitizer. A single 48-hour patch test with challenge two weeks later indicated that 20% Stearalkonium Chloride is not a sensitizer. On the basis of the evidence at hand, it is concluded that Stearalkonium Chloride is safe when incorporated in cosmetic products in concentrations similar to those presently marketed.