122 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS REFERENCES (1) Haberle, J. E., and Sperandio, G. J., J. Am. Pharm. Assoc., NS1,306 (1961). (2) Ward, J. B., and Sperandio, G. J., Am. Perfumer Cosmetics, 79, 53 (1964). (3) Ward, J. B., and Sperandio, G. J., J. Soc. Cosmetic Chemists, 15,327 (1964). (4) Lange, W. E., and Gonet, F. R., Ibid., 16, 563 (1965). (5) Sanders, P. A., Freon Aerosol Report A-59, E. I. du Pont de Nemours & Co., Wilming- ton, Delaware, 1963.

J. Soc. Uosmetic Chemists, 17, 123-130 (1966) A Guinea Pig Assay of the Photosensitizing Potential of Topical Germicides LEONARD J. VINSON, Ph.D., and VINCENT F. BORSELLI, B.S.* Presented September 8, 1965, New York Chapter Synopsis--In recent years there has been increasing use of germicides in soaps, detergents, and cosmetic products to provide significant benefits in the control of odor and minor second- ary infections. Even though these agents are carefully screened for safety and effectiveness, an occasional one which reaches the mass market is found to be a marginal sensitizer that escaped detection in animal tests and limited human panel studies. A guinea pig assay procedure is described which measures the photosensitizing potential of topical germicides. Data are presented relating the photosensitizing and cross photo- sensitizing activities of commercial germicides, viz., bisphenolics, halogenated salicylanilides, and halogenated carbanilides. Tetrachlorosalicylanilide and, to a lesser degree, bithionol are observed to be photosensitizers. The significance of these findings and results on other germicides in predicting the acceptability of a topical agent in soaps and cosmetics is dis- cussed. INTRODUCTION Photodermatitis is a phenomenon that has been known for many years. As far back as 1897, Stowers (1) described a case of skin eruption due to exposure to sunlight after contact with wild parsnips. Derma- titis in some individuals following use of eau de Cologne and exposure to sunlight was found to be due to certain essential oils oil of bergamot being chiefly responsible. Klaber (2) coined the name phytophoto- dermatitis for the skin condition resulting from contact with certain * Lever Brothers Co., Research Center, Edgewater, N.J. 123