UV-INDUCED SKIN TUMORS 195 (24) (25) (30) (31) (32) (33) (34) (35) (36) Mouse Epidermal Cell Cultures Treated With Tumor Promoters," in Mechanisms of Tumor Promotion and Carcinogenesis, T. J. Slaga, A. Sivak, and R. K. Boutwell, Eds. (Raven Press, New York, 1978), pp. 221-232. 16) D. H. Russell, "Ornithine Decarboxylase as a Marker of Carcinogenesis," in Handbook of Carcinogen Testing, H. A. Milman, and E. K. Weisburger, Eds. (Noyes Pub., Park Ridge, NJ, 1985), pp. 464- 481. 17) D. H. Russell, Ornithine decarboxylase: A key regulatory enzyme in normal and neoplastic growth, Drug Metab. Reviews, 16, 1-88 (1985). 18) G. G. Hillebrand, M. S. Winslow, M. J. Benzinger, D. A. Heitmeyer, and D. L. Bissett, Acute and chronic ultraviolet radiation induction of epidermal ornithine decarboxylase activity in hairless mice, Cancer Res., 50, 1580-1584 (1990). (19) T. G. O'Brien, R. C. Simsiman, and R. K. Boutwell, Induction of the polyamine-biosynthetic en- zymes in mouse epidermis by tumor promoting agents, Cancer Res., 35, 1662-1670 (1975). (20) T. G. O'Brien, R. C. Simsiman, and R. K. Boutwell, Induction of the polyamine-biosynthetic en- zymes in mouse epidermis and their specificity for tumor promotion, Cancer Res., 35, 2426-2433 (1975). (21) A. K. Verma, N.J. Lowe, and R. K. Boutwell, Induction of mouse epidermal ornithine decarbox- ylase activity and DNA synthesis by ultraviolet light, Cancer Res., 39, 1035-1040 (1979). (22) N. Lowe, A. K. Verma, and R. K. Boutwell, Ultraviolet light induces epidermal ornithine decar- boxylase activity, J. Invest. Dermatol., 71, 417-418 (1978). (23) R. L. Binder, M. E. Volpenhein, and A. A. Motz, Characterization of the induction of ornithine decarboxylase by benzoyl peroxide in SENCAR mouse epidermis, Carcinogenesis, 10, 2351-2357 (1989). P. Bohlen, J. Grove, M. F. Beya, J. Koch-Weser, M. H. Henry, and E. Grosshans, Skin polyamine levels in psoriasis: The effect of dithranol therapy, Eur. J. Clin. Invest., 8, 215-218 (1978). D. H. Russell, W. L. Combest, E. A. Duell, M. A. Stawiski, T. F. Anderson, and J. J. Voorhees, Glucocorticoid inhibits elevated polyamine biosynthesis in psoriasis, J. Invest. Dermatol., 71, 177-181 (1978). (26) N. J. Lowe, J. Breeding, and D. H. Russell, Cutaneous polyamines in psoriasis, Br. J. Dermatol., 107, 21-25 (1982). (27) G. Scalabrino and M. E. Ferioli, Degree of enhancement of polyamine biosynthetic decarboxylase activities in human tumors: A useful new index of degree of malignancy, Cancer Detection and Preven- tion, 8, 11-16 (1985). (28) D. L. Bissett, G. G. Hillebrand, and D. P. Harmon, The hairless mouse as a model to evaluate photoprotective materials, Photodermatol., 6, 228- 233 (1989). (29) D. L. Bissett, R. Chatterjee, and D. P. Harmon, Photoprotective effect of superoxide-scavenging anti-oxidants against ultraviolet radiation-induced chronic skin damage in the hairless mouse, Photo- dermatol. Photoimmunol. Photomed., 7, 56-62 (1990). D. L. Bissett, R. Chatterjee, and D. P. Harmon, Chronic ultraviolet radiation-induced increase in skin iron and the photoprotective effect of topically applied iron chelators, Photochem. Photobiol., 49s, 6 ls (1989). B. Halliwell, Superoxide-dependent formation of hydroxy radicals in the presence of iron salts, FEBS Lett., 96, 238-242 (1978). H. S. Black, Potential involvement of free radical reactions in ultraviolet light-mediated cutaneous damage. Photochem. Photobiol., 46, 213-221 (1987). J. Fitzpatrick, Soleil et peau, Med. Esthet., 2, 33-34 (1975). R. P. Arthur and B. S. Walter, The epidermal biopsy, Arch. Derm., 80, 133-135 (1959). G. Scalabrino, P. Pigatto, M. E. Ferioli, D. Modena, M. Puerari, and A. Caru, Levels of activity of the polyamine biosynthetic decarboxylases as indicators of degree of malignancy of human cutaneous epitheliomas,J. Invest. Dermatol., 74, 122-124 (1980). N. A. Shaath, Encyclopedia of UV absorbers for sunscreen products, Cosmet. Toilet., 102, 21-36 (1987).

j. Soc. Cosmet. Chem., 41, 197-207 (May/June 1990) Efficacy of novel hybrid powders to quench body malodors FUJIHIRO KANDA, TOSHIHIKO NAKANE, MASAHIRO MATSUOKA, and KEN-ICHI TOMITA, Shiseido Research Center, 1050 Nippa-cho, Kohoku-ku, Yokohama, Japan 223. Received May 16, 1990. Synopsis A hybrid powder consisting of a spherical resin core, with its surface uniformly covered with either zinc oxide or aluminum chlorohydrate, was developed to quench offensive body odors. This hybridization technique enables us to overcome some of the aesthetic shortcomings that deodorizing actives possess, without sacrificing any deodorizing efficacy. Improvement in powder texture of zinc oxide and aluminum chlorohydrate when hybridized with spherical polyethylene powder is demonstrated by applying them directly to skin and also by measuring their coefficients of kinetic friction. The effect of hybridization on deodorizing efficacy was also investigated by headspace gas chromatography. INTRODUCTION Certain powders, both organic and inorganic, possess unique functional characteristics of interest in cosmetic products. Unfortunately, the use of some of these compounds may be restricted due to their physical properties, depending on the system into which we wish to formulate them. For instance, titanium dioxide, a typical white pigment, is excellent in terms of its skin-covering properties, although its rough texture and rather high specific gravity limits its formulation into makeup cosmetics. On the other hand, spherical nylon powder, one of the most popular organic powders, possesses a smooth texture but is lacking in other respects. The concept of hybridization by coating one or more outer layer powders on the surface of a core powder to form a hybrid powder provides a possible means to overcome the shortcomings that each individual powder possesses and to still maintain or even enhance its original attractive properties. We first applied this technique to produce a hybrid or composite powder consisting of spherical nylon powder as the core powder whose surface is uniformly covered with fine-particle titanium dioxide. This was accomplished by mixing and compressing spherical nylon powder and titanium dioxide inside a mixer charged with ball-shaped mixing mediums. The resulting powder, which we named "hybrid fine powder," was excellent in terms of both texture and covering properties (1,2). We have recently analyzed foot odor (3-5) and axillary odor (3,4) (possibly the two most offensive body malodors) and reported that short-chain fatty acids comprise a considerable portion of the two malodors. GC/MS analyses revealed that isovaleric acid 197