138 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS Table V Comparison of Stratum Corneum Swelling Response With Known Irritancy of Several Surfactants Surfactant Swelling Response •* (% Increased from Hydrated Length) In Vivo Skin Irritation ** SLS 32 - 11 Severe within 1 day LAS 21 - 6 Severe within 1 day Tallow Soap (pH 10) 17 -+ 4 Intense by day 4 AEOS-3EO 14 _+ 3 Moderate by day 5 Tween 20 0.2 _+ 0.5 None by day 5 * Values are means _+ S.D. All means are significantly different, P • 0.05. Data are obtained after 1 hour incubation. Concentration used in the swelling test was 2% (w/w). ** The in vivo skin irritation results were taken from Tavss eta/. (4). not all act by the same mechanism to produce irritation as suggested by the present findings for different surfactants. ACKNOWLEDGMENTS We wish to acknowledge Dr. A.M. Kligman, Philadelphia, for supplying the stratum corneum samples and Dr. Philip Person, Flushing, New York, Dr. Robert Cagan, Dr. Ed Tavss, Mr. Ed Eigen, and Mr. John Blake-Haskins (Colgate-Palmolive) for critically reviewing the manuscript. REFERENCES (1) K. Fernee and C. R. Robbins, A quantitative index for area swelling of epidermal membrane, J. Soc. CosmeticChem., 32, 53-54 (1981). (2) C. R. Robbins and K. M. Fernee, Some observations on the swelling behavior of human epidermal membrane, J. Soc. Cosmetic Chem., 34, 21-34 (1983). (3) G.J. Putterman, N. F. Wolejsza, M. A. Wolfram, and K. Laden, The effect of detergents on swelling of stratum corneum, J. Soc. Cosmetic Chem., 28, 521-532 (1977). (4) E. A. Tavss, E. Eigen, and A.M. Kligman, Letter to the editor, J. Soc. Cosmetic Chem., 36, 251-254 (1985). (5) A.M. Kligman and W. M. Wooding, A method for the measurement and evaluation of irritants on human skin, J. Invest. Dermatol., 49, 78-94 (1967). (6) A. M. Kligman and E. Christophers, Preparation of isolated sheets of human stratum corneum, Arch. Dermato/., 88, 702-705 (1963). (7) G. W. Snedecor and W. G. Cochran, Statistical Rlethods, 6th ed. (Iowa State University Press, Ames, Iowa, 1967), pp 419-446. (8) J. Blake-Haskins, D. Scala, L. D. Rhein, and C. R. Robbins, Predicting surfactant irritation from the swelling response of a collagen film, acceptedJ. Soc. Cosmetic Chem., 1986. (9) J. G. Dominguez, F. Balaguer, J. L. Parra, and C. M. Pelejero, The inhibitory effect of some am- photeric surfactants on the irritation potention of alkylsulphates, Int. J. of Cosmetic Sci. 3, 57-68 (1981). (10) R. L. Gotdemberg, Reduction of topical irritation, J. Soc. Cosmetic Chem., 28, 667-679 (1977). (11) J. A. Faucher and E. D. Goddard, Interaction ofkeratinous substrates with sodium lauryl sulfate: 1. Sorption,J. Soc, Cosmetic Chem., 29, 323-337 (1978). (12) M. Miyazawra, M. Ogawa, and T. Mitsui, The physico-chemical properties and protein denaturation potential of surfactant mixtures, Int. J, of Cosmetic Sci., 6, 33-46 (1984).

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