5 Final Report on the Safety Assessment of Propylene Glycol Stearate and Propylene Glycol Stearate Self-Emulsifying

Abstract

Propylene Glycol Stearates (PGS) are a mixture of the mono- and diesters of triple-pressed stearic acid and propylene glycol and are used in a wide variety of cosmetic products. Studies with 14C-labeled PGS show that it is readily metabolized following ingestion. In rats, the acute oral LD50 has been shown to be approximately 25.8 g/kg. The raw ingredient produced no significant dermal toxicity, skin irritation, or eye irritation in acute tests with rabbits. Subchronic animal studies produced no evidence of oral or dermal toxicity. Propylene glycol monostea-rate was negative in in vitro microbial assays for mutagenicity. In clinical studies, PGS produced no significant skin irritation at concentrations up to 55% nor skin sensitization on formulations containing 2.5%. Photo-contact allergenicity tests on product formulations containing 1.5% PGS were negative. From the available information, it is concluded that Propylene Glycol Stearates are safe as cosmetic ingredients in the present practices of use.