Abstract  In vivo irritant or corrosive effects of squalan were determined using EPA OPPTS 870.2500 guideline. The test item was applied on rabbit skin during 4h. The test sites were scored for dermal irritation at 60min after removal of wrappings and scored again at 24, 48 and 72h. The modied Primary Irritating Index is 0.22. In conclusion, in this study, the squalan is considered non-irritant.

Abstract  Squalane and Squalene have been identified as natural components of human sebum. Both ingredients are used in a variety of cosmetics at concentrations ranging from 5 0.1 to > 504b. Animal studies indicate Squalene is slowly absorbed through the skin, while both compounds are poorly absorbed from the gastrointestinal tract. The acute animal toxicity of these ingredients by all routes is low. Both compounds are nonirritants to rabbit skin and eye at 100% concentration. Formulations containing Squalene indicate it is not a significant human skin irritant or sensitizer. limited contact sensitization tests indicate Squalene is not a significant contact allergen or irritant. It is concluded that both Squalane and Squalene are safe as cosmetic ingredients in the present practices of use and concentration.

Abstract  A biochemical method was employed to study the response of rabbit skin to isopropyl myristate, squalane, and decane. The results showed that decane damaged the skin so severely that the biosyntheses of lipids, RNA and DNA were reduced markedly for the first 3 days after application, but increased rapidly after that due to the repair. The effect of squalane was found to be weaker than that of isopropyl myristate, though both oils induced the stimulation of biosynthese in the epidermis. The magnitude of the biochemical effects of the 3 oils on the skin was increased in the order of squalane, isopropyl myristate and decane, which was consistent with the results of macroscopic and histological observations. From the profiles of the effects, it is postulated that the repairing processes are controlled by some feedback mechanisms.

Abstract  Percutaneous absorption of ethyl-alcohol (64175), perhydrosqualene (111013), and p-cymene (99876) was investigated. Male albino-mice were treated topically with 0.1 milliliter of radio labeled solutions of one of the test agents. In some tests with ethyl-alcohol and perhydrosqualene, the stratum corneum was removed before treatment. At selected times, the skin was removed and analyzed for radioactivity. Absorption rates were 10.5 and 0.12 nanomoles per square centimeter per minute for ethyl-alcohol and perhydrosqualene, respectively, for nonabraded skin. When the stratum corneum was removed, ethyl-alcohol penetration rate increased to 200 nanomoles per square centimeter per minute, but the rate for perhydrosqualene did not change. The penetration rate of p-cymene was 32 nanomoles per square centimeter per minute over 1 hour. The authors conclude that dermal absorption is affected by the epidermal barrier and the removal capacity of the blood. The liposolubility of the agent also affects its penetration through the epidermal stratum.

Abstract  Predisafe (rabbit cornea broblast cells culture) is an alternative method developped by Biopredic to determine the occular irritating potential. Cell layer was exposed to pure solution of perhydrosqualen (animal squalan) and cytotoxicity was evluated by neutral red colorimetric method. The results show an ocular tolerance inferior to 15, the substance is considered as slightly irritant for eyes.

Abstract  Assessment of mutagenic activity of squalane was conduced on "Salmonella typhimurium his-" and "Escherichia coli WP2(uvrA)" strains according to the OECD guideline n°471. There is no signicant difference between the number of spontaneaous reversions, the number of reversions obtained in the positive controls (with or without metabolica cativation), and the mean of corresponding experimental historic values obtained in the laboratory. There is no evidence of any increase of number of revertant colonies in the presence of the test substance (5000, 1000, 500, 100 and 50 µg) with or without metabolic activation for bacterial strains in Salmonella typhimurium TA1535, TA97a, TA98, TA100 and Escherichia coli WP2(uvrA).