SAFETY EVALUATION OF PERFLUOROPOLYETHERS, LIQUID POLYMERS USED IN BARRIER CREAMS AND OTHER SKIN-CARE PRODUCTS

Fomblin HC products are a 'family' of high-purity perfluoropolyethers manufactured for barrier cream and other personal care applications wh ich involve direct application to the skin. To confirm the safety of s uch use, representative Fomblin HC products were tested in experimenta l animals for acute toxicity, primary and repeated insult irritancy, s ensitization and photosensitization, subacute oral toxicity and comedo genicity; mutagenicity was examined in vitro, and irritancy or sensiti zation was also investigated on human skin (in patch tests with volunt eers). A high molecular weight Fomblin HC only was tested in rats for subacute oral toxicity and in man for dermal effects. Single oral dose s of 15 g/kg body weight were without evident toxicity to rats, as wer e single dermal applications or an ip injection at 5 g/kg. No primary irritant action was seen in rabbits or man, and similarly there was no evidence of skin sensitization or photosensitization in guinea pigs, or sensitization in man. No mutagenic action on Salmonella strains of tester bacteria was seen in repeat dose irritancy or oral toxicity tes ts in rabbits or rats, no adverse effects of Fomblin HC products were noted; in particular, daily oral administration (1000 mg/kg/day) to ra ts over 28 days produced no significant reaction. No comedogenic actio n was found. From the known chemistry of the perfluoropolyethers, the test programme reported here and the limited published data, it is con cluded that the intended use of Fomblin HC products in formulations ap plied to human skin has a high margin of safety. Copyright (C) 1996 El sevier Science Ltd.