394 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS Society of Cosmetic Chemists 1972 Merit Award Presentation The 1972 Society of Cosmetic Chemists Merit Award was presented to Dr. Karl Laden of Gillette Research at the December 12th luncheon during the Society's annual meeting in New York City. The award was given to Dr. Laden in recognition of his service to the Society in acting as editor of the SCC Journal for five years. The presentation of the plaque was made by President Martin Rieger, and Dr. Hyman Henkin of Helene Curtis served as Eulogist. Left to right: Merit Award Committee Chairman Hyman Henkin, Merit Award recipient Karl Laden, Mrs. Karl Laden, Society President Martin M. Rieger

I. Soc. Cosmet. Chem., 24, 395-398 (May 23, 1973) Laboratory and Clinical Evaluation of Antidandruff Preparations BERNARD IDSON, Ph.D.* Presented December 11, 1972, New York City Synopsis-Accelerated epidermal mitosis, which is characteristic of DANDRUFF, can be studied by incorporation of ISOTOPIC LABELING into cells, counting of the number of CORNEOCYTE CELLS, ULTRAVIOLET fluorescence microscopy, and determination of the levels of SULFHYDRYL in scalp skin. Reduction of the microbial flora of the scalp results in delay of reappearance of dandruff scale. The in vitro antimicrobial inhibition level is still the most widely used preclinical test. Weighing of removed scale is used principally in the LABORATORY. An animal test model using guinea pigs offers promise for it produced a dandruff-like syndrome. Clinical trial techniques are described. INTRODUCTION Dandruff represents an accelerated mitosis, or cell turnover resulting in des- quamation of visible scales. In the process of skin keratinization the normal scalp cells lose their nuclei and cytoplasmic content as they become cornified. Dandruff cells retain their nuclei and cellular fragments in their imperfect keratinization. The accelerated mitosis or reduced transit time of cells through the germinal layer of the epidermis, as well as the cytostatic action of anti- dandruff agents, has been followed by use of intradermal injection of radio- labeled compounds, particularly tritiated thymidine, and counting of the corneocyte cells (1). In the latter histological method, a plot of horny layer cells or corneocyte counts against time of use of a product is probably the best objective measurement of effectiveness. The scalp counts of individuals with•dandruff are two to three times as great as in normal subjects (1, 2). In- complete keratinization can also be detected by ultraviolet fluorescence microscopy and determination of the sulfhydryl levels of scalp skin (3). *Hoffmann-La Roche, Nutley, N.J. 07110. 395