ANTIPERSPIRANT ACTION OF ALUMINUM SALTS 367 (2) H. H. Relier, Factors affecting axillary sweating,J. $oc. Cosmet. Chem., 15, 99-110 (1%4). (3) E. H•51zle and A.M. Kligman, Mechanism of antiperspirant action of aluminum salts,J. Soc. Cosmet. Chem., (submitted for publication). (4) H. Tronnier and G. Rentschler, Experimentelle Untersuchungen zur Wirkungsweise aluminiumhal- tiger Antiperspiranzien,J. Soc. Cosmet. Chem., 24, 281-290 (1973). (5) W. B. Shelley and P. N. Horvath, Comparative study of the effect of anticholinergic compounds on sweating,J. Invest. Dermatol., 16, 267-274 (1951). (6) W. B. Shelley, P. N. Horvath, F. D. Weidman and D. M. Pillsbury, Experimental miliaria in man. I. Production of sweat retention anhidrosis and vesicles by means of iontophoresis,J. Invest. Dermatol., 11,275-291 (1978). (7) F. Herrmann and M. B. Sulzberger, Control of axillary sweating and of body odor, J. Amer. Med. x'zlJJ0oe., 167, 1115 (1958). (8) N. Hunziker and R. Brun, Experiences sur la transpiration. Action et dur•e d'effect de solutions de sels d'aluminium • divers pH, Dermatologica, 117,200-204 (1958). (9) R. Brun, Studies on perspiration,J. Soc. Cosmet. Chem., 10, 70-77 (1959). (10) H. P. Fiedler, "Der Schweiss," 2nd ed., Aulendorf, Cantor: 1%8 pp 303-377. (11) U. Schmid, N. Hunziker, R. Brun and W. Jadassohn, The protective effect of the sebaceous layer, Brit. J. Dermatol., 76, 395-397 (1964). (12) A.M. Kligman, The uses of sebum, Brit. J. Dermatol., 75,307-319 (1%3). (13) H. H. Reller and W. L. Luedders, Pharmacologic and toxicologic effects of topically applied agents on the eccrine sweat glands, in "Advances in Modern Toxicology, Vol. 4. Dermatotoxicology and Pharmacology," Francis N. Marzulli and Howard I. Maibach, Eds., Hemisphere Publishing Co.: Washington, London, 1977.

j. $oc. Cosmet. Chem., 30, 369-373 (November 1979) A skin moisturiation assay ROBERT L. RIETSCHEL Present Address Emory University School of Medicine, 215 IVoodruff Memorial Bldg., Atlanta, GA 30322. Received June 1, 1979. Presented at Annual Scientific Seminar, Society of Cosmetic Chemists, May 1979, Dallas, Texas. Synopsis The addition of WATER to STRATUM CORNEUM can be reflected in TRANSEPIDERMAL WATER LOSS (TWL) measurements obtained with an electrolytic water analyzer. Inhibition of TWL by occlusive moisturizers has been documented and, conversely, increases in TWL can be shown to reflect the hydration state achieved by occlusive plastic wrap, wet dressings, and skin moisturizers. INTRODUCTION Stratum corneum moisturization is accomplished fundamentally by the addition of water. This basic tenant of cutaneous biology was expounded in 1952 by Irvin Blank (1). Since then efforts to moisturize skin have taken two divergent directions. Products capable of occluding the skin are generally accepted as moisturizing enhancing and act by blocking evaporative water loss. However, they tend to be cosmetically unappeal- ing. The alternative has been to add water by applying hydroscopic agents to skin. The goal is to attract enough moisture to the area that stratum corneum will be plasticized. Objective evaluation of product occlusivity has been achieved by monitoring decreases in transepidermal water loss (TWL) (2,3). This same technology can be used to examine the moisture enhancing properties of humectants (4). If a product is applied to a normal individual's skin and the TWL is lowered, the product is considered occlusive. However, it may also have dried the skin by decreasing insensible sweating or diminished the amount of water present in the stratum comeurn. If higher than normal TWL readings are achieved, the product may have 1) damaged the horny layer allowing an increase in exudation of body fluids, 2) altered the horny layer in such a way as to increase water transpiration without damage to the integretity of the layer, 3) stimulated insensible sweating or 4) added and held moisture within the stratum corneum and it is being detected. Moisture added by methods 2, 3, or 4 should be useful in the treatment of dry skin. The higher than normal TWL readings which occur Dermatology Service, Department of Medicine, Brooke Army Medical Center, Fort Sam Houston, Texas 78234. 369