JOURNAL OF COSMETIC SCIENCE 154 DETERMINATION OF SAFROLE LEVELS IN ESSENTIAL OIL SAMPLES FROM MARKETS We used Stout Camphor essential oil prepared by ether extraction from Stout Camphor wood as the positive control and determined the safrole contents in 15 commercially available Stout Camphor essential oil samples, Small-fl ower Camphor essential oil (upper layer and lower layer) samples, and one sample each of cypress oil, natural peppermint oil, China oil, Pak Fah Yeow, Green oil and Cardamom fl ower oil (23 samples in total). Using the method developed in this study, safrole was detected in 21 of the 23 samples. All 15 Stout Camphor essential oil samples purchased from markets were found to contain safrole, in levels ranging from 37.65 to 355.07 mg/g. The upper layer of Small-fl ower Camphor essential oil did not have a detectable level of safrole, whereas the lower layer of the essential oil had up to 642.98 mg/g of safrole. The safrole levels in the remaining essential oil sam- ples were as follows: cypress oil, 129.11 mg/g natural peppermint oil, 35.28 mg/g China oil, 109.56 mg/g Pak Fah Yeow, 33.37 mg/g Green oil, 0 mg/g and Cardamom fl ower oil, 22.06 mg/g. The results indicated that many of the Stout Camphor essential oils and other essential oils available on the market have high levels of the carcinogenic agent safrole. CONCLUSION In this study, we developed a fast and simple gas chromatographic method to quantify saf- role in essential oils. The method only requires the addition of an IS DA methanol solution, Table V Safrole Contents of Various Commercially Available Essential Oils Sample Content (mg/g)a Stout Camphor essential oil (extracted by ether) 32.73 Small-fl ower Camphor essential oil (upper layer) ND Small-fl ower Camphor essential oil (Lower layer) 642.98 Commercial Stout Camphor essential oil (S1) 37.65 Commercial Stout Camphor essential oil (S2) 306.52 Commercial Stout Camphor essential oil (S3) 326.98 Commercial Stout Camphor essential oil (S4) 256.18 Commercial Stout Camphor essential oil (S5) 281.60 Commercial Stout Camphor essential oil (S6) 196.48 Commercial Stout Camphor essential oil (S7) 136.46 Commercial Stout Camphor essential oil (S8) 176.85 Commercial Stout Camphor essential oil (S9) 301.65 Commercial Stout Camphor essential oil (S10) 355.07 Commercial Stout Camphor essential oil (S11) 269.70 Commercial Stout Camphor essential oil (S12) 227.09 Commercial Stout Camphor essential oil (S13) 304.91 Commercial Stout Camphor essential oil (S14) 199.76 Commercial Stout Camphor essential oil (S15) 278.37 Cypress oil 129.11 Natural peppermint oil 35.28 China oil 109.56 Pak Fah Yeow 33.37 Green oil ND Cardamom fl ower oil 22.06 a Average of duplicate analyses. (24) ND: not detected.

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