126 JOURNAL OF COSMETIC SCIENCE Table II Assay of Commercially Available Products % Total lactic % Total glycolic % Total acid acid salicylic acid Product 1: Alpha hydroxy lotion 4.1 Product 2: Refining toner 0.22 0.91 Product 3: Alpha hydroxy lotion 3.7 Product 4: Alpha hydroxy lotion 1.7 Product 5: Hydroxy cream 3.6 Product 6: AHA facial treatment 5.5 Product 7: Lotion 2.8 5.9 Product 8: AHA body lotion 5.1 Product 9: AHA hand cream 5.8 Product 10: AHA hand lotion 4.1 Product 11: Eye cream 0.48 Product 12: Facial masque 1.1 0.51 O.O3 0.15 curves for derivatized hydroxy acid standard mix and a commercially available personal care product are shown in Figure 1. ACCURACY AND PRECISION Linearity studies demonstrated excellent linearity in the working range expected in commercial personal care products, detailed in Figure 2. Methodology validation studies were conducted in which placebo personal care products were spiked with varying levels of sodium L-lactate, glycolic acid, and salicylic acid, and analyzed using this method. Average recoveries of lactic acid, glycolic acid, and salicylic acid were 99.74%, 99.16%, and 99.40%, respectively, with an average standard deviation of 2.2, and are detailed in Table I. Results obtained from analyzing commercially available personal care products are detailed in Table II. REFERENCES (1) D. de Villiers, E. Wurster, T. Bergh, and K. Narsai, Stability-indicating HPLC assay of the alpha hydroxy acids lactic acid and glycolic acid in nonionic creams, Pharmazie, 53, 204-205 (1998). (2) S. Scalia, R. Callegari, and S. Villani, Determination of glycolic acid in cosmetic products by solid- phase extraction and reversed-phase ion-pair high-performance liquid chromatography,J. Ch,vmatogr., 795, 219-225 (1998). (3) K. Nakamura, Y. Morikawa, and I. Matsumoto, Studies on high-speed liquid chromatography in cosmetic analysis, Bunseki Kagakz•, 29, 314-318 (1980). (4) J. D. Blake, M. M. Clarke, and G. N. Richards, Determination of organic acids in sugar cane process juice by high-performance liquid chromatography, J. Chromatogr., 398, 265-277 (1987). (5) S.H. Ashoor and J. Welty, Determination of organic acids in foods by high-performance liquid chromatography, J. Chromatogr., 287, 452-456 (1984). (6) P.S. Nassos, J. E. Schade, A.D. King, and A. E. Stafford, Comparison of HPLC and GC methods for measuring lactic acid in ground beef, J. Food Sci., 49, 671-674 (1984). (7) K. Molever, Quantitative determination of glycerin in soap by capillary gas chromatography, J. Am. Oil Chem. Soc., 64, 1356-1357 (1987). (8) K. Molever, Quantitative determination of sodium lauroyl sarcosinate by gas chromatography,J. Am. Oil Chem. Soc., 70, 101-103 (1992).

j. Cosmet. Sci., 53, 127-150 (March/April 2002) Papers Presented at the 2001 Annual Scientific Meeting and Technology Showcase (Friday's Program) December 6-7, 2001 New York Hilton New York, NY 127