JOURNAL OF COSMETIC SCIENCE 230 tical exposures. Consequently, we cannot recommend porcine skin for routine mildness screening by 14 C-SDS penetration. ACKNOWLEDGMENTS Financial support for this research was provided by the Procter and Gamble Company. We thank Tiffany Brooks and Keun Il Kim for help in conducting the human skin pen- etration assays. APPENDIX Tabular results for 10- and 2-min 14 C-SDS penetration into human skin (Tables III and IV). REFERENCES (1) P. N. Moore, S. Puvvada, and D. Blankschtein, Challenging the surfactant monomer skin penetration model: Penetration of sodium dodecyl sulfate micelles into the epidermis, J. Cosmet. Sci., 54(1), 29–46 (2003). (2) C. Froebe, F. Simion, L. Rhein, R. Cagan, and A. Kligman, Stratum corneum lipid removal by surfac- tants: Relation to in vivo irritation, Dermatology, 181(4), 277–283 (1990). (3) S. Ghosh and D. Blankschtein, The role of sodium dodecyl sulfate (SDS) micelles in inducing skin bar- rier perturbation in the presence of glycerol, J. Cosmet. Sci., 58, 109–133 (2007). (4) M. J. Fevola, R. M. Walters, and J. J. LBrizzi, A new approach to formulating mild cleansers: Hydrophobically-modified polymers for irritation mitigation, in Polymeric Delivery of Therapeutics, S. E. Morgan and R. Y. Lochhead, eds. (American Chemical Society, New York, 2010), pp. 221–242. Table IV Treatments, Sample Sizes, and 14 C-SDS Disposition for 2-min Exposure on Human Skin (Expt. 2) Treatment μg/cm2 14 C-SDS equivalents Wipe Receptor Penetration (+) SE (-) SE 50 mM SLS (control) (n = 20) 3.2 ± 0.6 0.06 ± 0.04 7.3 1.2 1.0 50 mM SLS + 2% PEO (n = 21) 3.1 ± 1.5 0.07 ± 0.05 3.5 0.5 0.5 50 mM SLS + 2% PVA (n = 21) 3.2 ± 0.4 0.11 ± 0.07 5.3 0.8 0.7 Columns have the same meaning as in Table III. Table III Treatments, Sample Sizes, and 14 C-SDS Disposition for 10-min Exposure on Human Skin (Expt. 1) Treatment μg/cm2 14 C-SDS equivalents Wipea Receptorb Penetrationc (+) SE (-) SE 50 mM SLS (control) (n = 14) 8.0 ± 1.9 0.03 ± 0.01 16.0 2.3 2.0 50 mM SLS + 2% PEO (n = 15) 2.8 ± 0.6 0.05 ± 0.03 6.5 0.8 0.7 50 mM SLS + 2% PVA (n = 14) 12.9 ± 7.0 0.09 ± 0.05 11.3 1.5 1.3 a Radioactivity removed with wetted fi lter papers after the wash step. b Radioactivity measured in receptor solution. c Geometric mean of the total radioactivity found in all layers of skin + receptor solution.

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