The Safety And Efficacy Studies Of True Lavender Essential Oil And Ku-shui Rose Essential Oil

Essential oil plays an increasingly important role in the efficiency application field like adjunctive therapy and aesthetic health care.However,it is because of the lack of related laws and regulations,Chinese oil products exsist huge potential safety hazard.Therefore,true lavender(Lavandula angustifolia)and Ku-shui rose(Rosa Setate × Rosa Rugosa)were chosed to study their acute toxicity,repeated-dose toxicity,skin irritation,skin sensitization,eye irritation,and anti-anxiety efficacy.The first step,two types of essential oils were extracted by steam distillation and their components were identificated by Gas chromatography-mass spectrometer.The results showed that linalool(29.71%)and linalyl acetate(27.06%)relatively occupy most in the true lavender essential oil,meanwhile,citronellol(36.19%)and geraniol(18.02%)relatively occupy most in the Ku-shui rose essential oil.The second step,the experiments of acute toxicity and repeated-dose toxicity were conducted via guinea pig Buehler test.The hepatic and renal toxicity of essential oils were evaluated by guinea pigs’ weight change,blood routine and biochemical indexes,organs observation after gross anatomy,weight coefficient of organs and tissue slice observation of organs.The result of cute toxicity test showed that median lethal dose of true lavender essential oil and that of Ku-shui rose essential oil are both higher than 10000 mg/kg.In addition,the results of repeated-dose toxicity found that,after treated for 7 days with the dose of greater than 1250mg/kg,the animals in true lavender group and Ku-shui rose group all showed hepatotoxic effects and renal toxic effects.The lowest observed toxic effect level of true lavender essential oil is 1250mg/kg,while the lowest observed toxic effect level of Ku-shui rose essential oil is 625mg/kg.The third step,murine local lymph node assay was conducted to study the skin irritation and sensitization.Briefly,the right ears of mice were exposed to essential oils with different concentrations,and auricle thickness and weight change were used to study irritation,and the change of lymph nodes weight and proliferation of lymphocyte were used to study sensitization.The result showed that both of pure true lavender essential oil and pure Ku-shui rose essential oil are irritant and allergenic.The allergenic level of true lavender essential oil is “medium”,while the allergenic level of Ku-shui rose essential oil is “severe”.No observed irritant effect level and allergenic effect level of true lavender essential oil are 25%.While,no observed irritant effect level of Ku-shui rose essential oil is 25%,and no observed allergenic effect is 12.5%.The fourth step,hen’s egg-chorioallantoic membrane assay was performed to study the eye irritation.The chorioallantoic membranes(CAM)were exposed to essential oils with different concentrations.And then,stereo microscope was used to observe the blood vessel on CAM.The occurrence time of bleeding,dissolution,and coagulation were recorded to evaluate the level of eye irritation.The result proved that both of the eye irritant level of pure true lavender essential oil and pure Ku-shui rose essential oil are “severe”,and no observed eye irritant effect level of true lavender essential oil is 25%,while no observed eye irritant effect level of Ku-shui rose essential oil is 12.5%.The fifth step,based on the results of safety studies,volunteers’ skin applying assay with safe concentration and dose was conducted to study anti-anxiety efficacy.We recruited volunteers and assigned them randomly into control group or essential oil groups.The base oil or plant essential oil was applied to the skin after volunteers were made anxious by mental arithmetic test(MAT).The difference of physical signs,such as blood pressure and heart rate variety,after MAT and after oil absorption were compared.The result showed the acute anxiolytic-like effect of true lavender is better than Ku-shui rose,meanwhile,the concentration of 1% was proved safe.This research might provide scientific basis for the use of essential oils and data support for the establishment of relevant standards.