724 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS tissues and common buffer systems. Sweat inhibition by aluminum can be related to some degree to tissue sorption and that relative sorption can now be measured as a function of impedance change on excised stratum corneum. Aluminum chlorohydroxide sorbs to skin more quickly than aluminum chloride and this is reflected in a five-fold greater effect on impedance. The skin impedance data for aluminum chloride and aluminum chlorohydrox- ide correlate well with dextran and guinea pig stratum corneum binding data as determined by gel filtration chromatography and morin fluorescence analysis. The electrometric technique discussed in this report can be used as a laboratory method for estimating the sorption and/or antiperspirant potential of ionic salts. REFERENCES (1) E. S. Bretschneider, A.M. Rubino and J. j. Margres, Antiperspirant efficacy, Presented at 9th Congress, International Federation of Societies of Cosmetic Chemists, Boston, June 7, 1976. (2) Author's personal communication. (3) M. Ainsworth, Methods for measuring percutaneous absorption, J. Soc. Cosmet. Chem., 11, 69 (1960). (4) I. H. Blank, Percutaneous absorption, J. Occup. Med., 2, 5 (1960). (5) I. H. Blank, Cutaneous barriers, J. Invest. Dermatol., 45, 249 (1965). (6) R. T. Tregear, "Physical Functions of Skin," Academic Press, New York, 1966, pp 6-13. (7) R.J. Scheuplein and I. H. Blank, Permeability of the skin, Physiol. Rev., 51, 702 (1971). (8) A.M. Kligman, The biology of the stratum comeurn, in W. Montagna and W. Lobitz, "The Epidermis," Academic Press, New York, 1964, Chapter XX. (9) F. N. Marzulli, Barriers to skin penetration, J. Invest. Dermatol., 39, 387 (1962). (10) C. A. Squier and R. M. Hopps, A study of the permeability barrier in epidermis and oral epithelium using horseraddish peroxidase as tracer in vitro, Brit. J. Dermatol., 95, 123 (1976). (11) R. T. Tregear, Interpretation of skin impedance measurements, Nature, 205, 600 (Feb. 1965). (! 2) J. D. Montagu and E. M. Coles, Mechanism and measurement of the galvanic skin response, ?sychol. Bull., 65, 261 (196). (13) A. C. Allenby, J. Fletcher, C. Schock and T. F. S. Tees, The effect of heat, pH and organic solvents on the electrical impedance and permeability of excised human skin, Brit. J. Dermatol., 81 (Suppl. 4), 31 (1969). (14) P. H. Duggard and R.J. Scheuplein, Effects of ionic surfactants on the permeability of human epidermis: an electrometric study, J. Invest. Dermatol., 60, 263 (1973). (15) K. E. Malten and F. A.J. Thiele, Evaluation of skin damage II, Brit. J. Dermatol., 89, 565 (1973). (16) F. A.J. Thiele and K. E. Malten, Evaluation of skin damage, Brit. J. Dermatol., 89, 373 (1973). (17) H. Kramer and P. Meares, Correlation of electrical and permeability properties of ion-selected membranes, BiophysicalJourn., 9, 1006 (1969). (18) R. Edelberg, "Biophysical Properties of the Skin," Wiley-Interscience, New York, 1971. (19) O. Kadem and A. Leaf, The relation between salt and ionic transport, J. Gen. ?hysiol., 49, 655 (1966). (20) N. Lakshminarayanaiah, Transport phenomena in artificial membranes, Chem. Rev., 65, 491 (1965). (21) M.J. Bartek, J. A. LaBudde and H. I. Maibach, Skin permeability in vivo: comparison in rat, rabbit, pig and man, J. Invest. Dermatol., 58, 114 (1972). (22) R.J. Scheuplein, Mechanism of percutaneous adsorption, J. Invest. Dermatol., 45, 334 (1965). (23) R.J. Scheuplein and L. W. Ross, Mechanism of percutaneous absorption, J. Invest. Dermatol., 62, 353 (1974). (24) I. H. Blank and R.J. Scheuplein, The relationship of the structure of the epidermis to percutaneous absorption, Brit. J. Dermatol., 89(Suppl. 4), 4 (1969). (25) S. Riegelman, Pharmacokinetic factors affecting epidermal penetration and percutaneous absorption, Pharmacokinetics, 16, 873 (1975). (26) R.J. Scheuplein, I. H. Blank, G.J. Brauner and D.J. MacFarlane, Percutaneous absorption of steroids, J. Invest. Dermatol., 52, 63 (1969). (27) R. B. Stoughton, Percutaneous absorption: a personal view, J. Invest. Dermatol., 63, 305 (1974). (28) P. Grasso and A. B. G. Lansdown, Methods of measuring and factors affecting percutaneous absorption, J. Soc. Cosmet. Chem., 23, 481 (1972).

CHARACTERIZING ALUMINUM SKIN INTERACTION 725 (29) J. C. Lawler, M.J. Davis and E. C. Griffith, The impedance of the surface sheath and deep tissues,J. Invest. Dermatol., 34, 301 (1960). (30) R. Plutchik and H. R. Hirsch, Skin impedance and phase angle as a function of frequency and current, Science, 141,927 (1963). (31) G.J. Putterman, J. Strassburger, A. H. Waldman and J. J. Fitzgerald, Methods for estimating aluminum sorption to skin, Blochem. Med., 18, 21 (1977). (32) J. j. Fitzgerald and J. R. Rand, Application of gel filtration chromatography to metal ion hydrolysis studies, Presented at First Chemical Congress of North American Continent, Mexico City, December 5, 1975. (33) J. J. Fitzgerald, Application of gel filtration chromatography to the understanding of basic aluminum polymers, J. coil Inter. $ci., (in press). (34) J.J. Fitzgerald, Macromolecular properties of aluminum hydroxychloride polymers, Presented at National ACS Meeting, Inorg. Div., New Orleans, March 24, 1977.