394 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS gredients and formulations, patch test kits for diag- nostic purposes, experimental or custom formula- tions, and other services to dermatologists to assist them in treating patients. An improved relation- ship between practicing dermatologists and cos- metic scientists should result from this information exchange designed to benefit the patient, who is also a cosmetic consumer. Specific suggestions will be offered on types of services the cosmetic scientist can offer and what information can be gathered in such situations. Instrumental and historical methods to identify sensitive skinned individuals Howard Maibach, M.D., University of California, School of Medicine, Department of Dermatology, Box 0989, San Francisco, CA 94143 Kaija Lam- mintausta, Turku University, Finland and Enzo Berardesca, Pavia University, Italy Many consumers and patients feel that they have "sensitive" skin and cannot tolerate soaps, deter- gents, cosmetics, textiles, moisturizers, sun screens, dermatologic drugs and fabric softeners. This paper will update our efforts to define facile and robust methods not only for demonstrating that these subjects' skins are different, but for categor- izing some of the dermatologic abnormalities. "Look Good .... Feel Better" Bernadette Toomey, B.A., M.A., The Cosmetic, Toiletry and Fragrance Association, 1110 Vermont Avenue, N.W., Suite 800, Washington DC 20005 Ms. Toomey, Vice President, CTFA Foundation, will discuss the national public service program "Look Good . . . Feel Better." This program is being developed by the CTFA Foundation in part- nership with the American Cancer Society and the National Cosmetology Association, and deals with the negative appearance changes that occur because of chemotherapy and radiation treatments. "Look Good . . . Feel Better" will provide a net- work of support by utilizing volunteers from the ACS, cosmetologists, and health professionals, to offer "Look Good . . . Feel Better" programs in a variety of settings, including hospitals, community centers, and salons. It is being piloted this fall at Memorial Sloan-Kettering in New York City, the Lombardi Cancer Center in Washington, D.C., and through the NYC Division of the American Cancer Society. A national announcement of the program will be made when the Cosmetic, Toiletry and Fragrance Association Board has its Annual Meeting at Boca Raton in February 1989. "Look Good . . . Feel Better" will then be phased into approximately ten states and Comprehensive Cancer Centers through- out the United States. "Look Good . . . Feel Better" is a unique opportunity for the cosmetic in- dustry to provide a valuable public service. SESSION C SUNSCREENS Sunlight, skin cancer, and aging of the skin Frederick Urbach, M.D., Center for Photobiology, Skin and Cancer Hospital, Temple University School of Medicine, 3322 North Broad Street, Phil- adelphia, PA 19140 Examination of the sun's role in the production of human skin cancer does not lend itself to direct ex- perimentation. However, extensive astute observa- tions have strongly suggested the etiologic signifi- cance of light energy in the induction of these tumors. Skin cancers in Caucasians in general are most prevalent in geographic areas of the greatest isolation and among people who receive the most exposure, i.e., men who work outdoors. They are rare in Negroes and other deeply pigmented indi- viduals who have the greatest protection against UV light injury. Further, the lightest complexioned in- dividuals, such as those of Scottish and Irish de- scent, appear to be the most susceptible to skin cancer formation when they live in geographic areas of high-UV exposure. "Aging" of skin is also due to chronic UVR expo- sure. Proper use of sunscreens can reduce all these effects. Prevention of skin cancer in mice by sunscreens Hans Chr. Wulf, M.D., Department of Derma- tology, Laboratory of Photobiology, University Hospital, Rigshospital, Blegdamsvej 9, 2100 Co- penhagen, Denmark Sunscreens have been tested for their capability of delaying or preventing skin cancer in hairless, pig- mented mice exposed to artificial ultraviolet (UV) radiation four times weekly. Increasing UV doses were used, so that the dose delivered to the un- treated control group was kept close to the tolerable dose. The same dose was used in the mouse groups to which sunscreens were applied. Tumorigenesis was demonstrated to be increasingly delayed the higher the SPF. However, all UV-irra- diated mice got tumors within the study period of 18 months. Histologic examinations revealed that all irradiated mice had squamous cell carcinomas. Metastases to lymph nodes and lungs were found in only 10% of the mice.

ABSTRACTS 395 The sun protection substances not only delayed the skin cancer development, but also delayed the time of death of the animals irradiated with the ultravi- olet rays, UV stability of sunscreens? A model for in vitro testing H. U. Gonzenbach, Ph.D., G. Klecak, MD, and R. Schwarzenbach, Givaudan S.A., 5 Chemin de la Parfumerie, CH-1214 Vernier, Geneva, Switzer- land (H.U.G., R.S.), and F. Hoffmann-LaRoche & Co Ltd. (G.K.) The question whether a sunscreen molecule is pho- tostable or not is being raised more and more often. Simple U¾-absorption measurements before and after UV exposure cannot provide a reliable answer although suggested in the literature. Such single- point measurements do not allow to distinguish be- tween irreversible degradation (case I) and reversible changes such as double-bond isomerization (case II) leading to a stable photostationary equilibrium. A kinetic study is required or a cross-check by an in- dependent method (e.g., HPLC) in order to differ- entiate case I and II. An in vitro model is proposed featuring ease of kinetic studies and an optional possibility for HPLC analysis. Examples for both cases I and II were studied with this model under natural sunlight as well as with different artificial light sources. Methods for testing sunscreens: DIN versus FDA methods R. E. Davies, Ph.D., Temple University, 3322 North Broad Street, Philadelphia, PA 19140 The sun protection factor (SPF) is an indirect index of sunscreen efficacy. Such indices have general comparative value only if they are obtained under "comparable" conditions and if they reflect ade- quately the effects of significant variables. The two most widely used methods for estimating the SPF index differ significantly with respect to the radia- tion source and the rate of application of the test material. Theoretical considerations suggest that the DIN method may produce relatively lower nu- meric SPF values for sunscreens of low protective efficacy because of a lower application rate com- pared to the FDA method. Conversely, DIN meth- odology may produce relatively higher values for sunscreens of high efficacy because of the absence of longer wavelength radiation from its radiation source. Direct evaluation indicates that these ten- dencies may cancel, but it appears that achievement of equivalent estimates is fortuitous rather than in- evitable. Methodologies for testing sunscreen UVA pro- tection C. A. Cole, Johnson & Johnson Baby Products, Grandview Road, Skillman, N.J. 08558 Standard methodologies have been established for the determination of sunscreen efficacy against acute sunburn and yield the familiar sun protection factors (SPFs). This measure indicates primarily the protection provided by the sunscreen against ultra- violet B (UVB) radiation. Similar testing of UVA protection is much more difficult because of the low sensitivity of individuals to UVA radiation for acute reactions, namely erythema. To enhance the sensi- tivity of individuals to UVA radiation for sunscreen testing, phototoxic materials such as 8-methoxy- psoralen (8-MOP) or anthracene have been utilized. These two materials cause sensitivity in two dis- tinctly different regions of the UVA and would yield different protection factors when testing one sunscreen product. In addition, the choice of the irradiation source would also have a profound effect on the outcome of the test results. In vitro testing methodologies may offer a partial solution to this dilemma and will be discussed. SESSION D HAIR Research on the mechanism by which minox- idil stimulates hair growth Gerald R. Zins, Ph.D., Hairgrowth Research, The Upjohn Company, Henrietta Street, Kalamazoo, MI 49001 Clinically, minoxidil stimulates hair growth by in- creasing the proportion of follicles in anagen. Ini- tially, many supposed this was due to enhanced fol- licular blood flow. Indeed, minoxidil is quite unique among vasodilating agents in enhancing blood flow to the skin, but this hypothesis has not been supported in man. A basic question con- cerning how minoxidil works is whether the parent molecule or a metabolite is responsible. Minoxidil sulfate accounts for the relaxation of vascular smooth muscle and works by opening potassium channels in the cell membrane. It is not clear whether a similar action is exerted on the hair fol- licle either by minoxidil or its sulfated derivative. Nevertheless, both agents stimulate hair shaft growth in cultured follicles, making it clear that an action independent of vasodilitation is being ex- erted. Studies of gene expression suggest that min- oxidil's action in cultured follicles involves activa- tion at the beginning of a normal process of cell division.