LAVENDER OIL/WATER/STABILIZER SYSTEMS 439 Table IV The Percent Composition for Samples for the Water/Lavender Oil/Laureth 4 System for the Determination of Evaporation Pathways Sample % Water % Lavender % Laureth % Water % Lavender % Laureth before oil before 4 before after oil after 4 after evaporation evaporation evaporation evaporation evaporation evaporation B1 13.0 3.0 84.0 14.5 0.0 85.5 B2 14.0 6.0 80.0 15.8 2.8 81.4 B3 17.0 14.0 69.0 18.3 11.1 70.6 B4 12.0 19.0 69.0 15.5 14.7 69.8 B5 3.0 26.0 71.0 7.3 21.3 71.4 B6 1.0 29.0 70.0 5.7 24.1 70.2 B7 1.5 37.5 61.0 6.1 32.2 61.7 B8 1.5 55.5 43.0 5.9 50.5 43.6 not straight lines, but curved ones, far from the water corner, but in a way that reduced the percent of fragrance (Figure 8) (18). For the 35øC evaporation, the compositions of selected samples are given in Table IV, showing the percentage of each sample before evaporation and after evaporation. Figure 9 shows the positions of these samples before and after warm evaporation. For our system, a different approach was chosen, and the weights of samples were reported while the refractive indices were measured for the liquid and the vapors to relate the pathway of the evaporation. From the results of the refractive index and the weights Lavender oil © Before evaporation ß After evaporation B• B6 B5 B4 B3 B2 BI Laureth 4 Water Figure 9. Positions of selected samples before and after warm evaporation and their evaporation pathways. O, position of sample before evaporation l, position of sample after evaporation.

440 JOURNAL OF COSMETIC SCIENCE of samples before and after evaporation for the liquid samples (Table IV), the positions of the samples before and after evaporation are pointed out in Figure 9, which clarifies that the pathways are not straight lines but curves. At room temperature the water is the first to evaporate, but once the temperature is raised to 35øC, the lavender oil or some of its compounds evaporate first. This was expected, since water supports the evaporation of fragrance material, and at this tem- perature it helps to drive off the volatile compounds. CONCLUSION The structural changes observed during evaporation of the fragrance emulsions can be related to the different amphiphilic association structures in the phase diagram. Fra- grance solublization studies have shown how fragrance ingredients are solubilized in surfactant solution (L2) and how such a system serves as a fragrance reservoir. The different intermolecular interactions between the fragrance compounds and the surfac- tant results in different patterns during evaporation of the fragrance emulsion as well as of the microemulsion. Although at room temperature water is the first to evaporate, the higher surfactant solutions evaporate more slowly and retain their weight for slow and fast evaporations. Once the temperature is raised to 35øC, lavender oil or some of its compounds evaporate first, since water supports the evaporation of fragrance material and at this temperature helps to drive off the volatile compounds. ACKNOWLEDGMENTS The author thanks the Deanship of Academic Research of the University of Jordan for funding this research project, and also Ayat Bozeya and Tamador A1-Ahmad for their valuable help. REFERENCES (1) Kirk-Othmer, Encyclopedia of Chemical Technology, 3rd ed. (John Wiley & Sons, New York, Chichester, Brisbane, Toronto, Singapore, 1981), vol. 16, p. 324. (2) O. Secondini, Handbook of Perfumes & Flavors (Chemical Publishing Co., New York, 1990), p. 48. (3) A. Dale and S. Cornwell, The role of lavender oil in relieving perineal discomfort following childbirth: A blind randomized clinical trial, J. Adv. Nursing, 19, 89-96 (1994). (4) C. Dunn, J. Sleep, and D. Colerr, Sensing an improvement: An experimental study to evaluate the use of aromatherapy, massage and periods of rest in an intensive care unit, J. Adv. Nursing, 21, 34•40 (1995). (5) K. Hm and C. Sh, Lavender oil inhibits immediate-type allergic reaction in mice and rats,J. Pharm. Pharmacol., 51,221-226 (1999). (6) M. Billany, S. Denman, S. Jameel, and J. K. Sugden, Topical antirheumatic agents as hydroxyl radical scavengers, Int, J. Pharmacol., 124, 279-283 (1995). (7) S. Nyiredy, B. Renata, and T. Heinz, Gas chromatographic retention behavior of substances of plant origin, Acta Pharm. Hung., 55, 49-58 (1985). (8) E. Revenchon, G. Dellaporte, and F. Senatore, Supercritical CO 2 extraction and fractionation of lavender essential oil and waxes, J. Agr. Food Chem., 43, 1654-1658 (1995). (9) V. D. Zheljazkov and N. E. Nielsen, Studies on the effect of heavy metals (Cd, Pb, Cu, Mn, Zn and Fe) upon the growth, productivity and quality of lavender, J. Essential Oil Res., 8, 259-274 (1996).