42 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS of such materials as polymers and environmental pollutants. MAECIS: A chemical structure and informa- tion handling system Gary S. Zander and William E. Brugger, Ph.D., IFF, 1515 Highway 36, Union Beach, NJ 07735. In order to meet an existing need for a computer- ized chemical information and structure handling system in R & D, a program was developed which integrates both chemical information management and structure manipulation capabilities into one package. Chemical information management in- cludes entry, modification, and retrieval of chemi- cal structures and associated information. Retrieval capabilities include selection by names, in-house code numbers, CAS registry numbers, structure matching, substructure searching, or by selected physical properties such as molecular weight. Structure manipulation capabilities include molec- ular modeling, rotation, conformational analysis, and calculation of various molecular parameters such as octanol/water partition coefficients. The program is highly graphics-oriented and has enjoyed wide user acceptance. HAIR & SKIN Mechanism of hair waving Linda Albrecht and Leszek J. Wolfram, Ph.D., Clairol Research Laboratories, 2 Blach!• ? Rd., Stamford, CT 06902. Comparative waving efficacy of aqueous solutions of alkali surfites and thioglycolates was evaluated using novel laboratory techniques of "slack" and coil setting. Excellent correlation with on-head waving conditions have been obtained in the case of coil setting. The waving data suggest significant differences in the waving mechanism between sulfite and thioglycolic acid. With sulfite as the reagent, the optimum setting is attained at pH 7 in spite of the fact that cleavage level of sulfite- treated hair is at maximum in the pH region 3-6. The low settability of thio-reduced hair at low pH values is due not to the lack of bond rebuilding but rather to limited conformational changes (low swelling) under such conditions. Cutaneous absorption of cosmetic ingre- dients-Realities and potentialities Gordon L. Flynn, Ph.D., University of Michigan College of Pharmacy, Ann Arbor, MI 48109. Cosmetics are complex systems which contain ingredients of wide-ranging physio-chemical prop- erties. Important questions arise as to how much of the respective ingredients passes into the viable tissues and to what extent can such percutaneous absorption be estimated a priori. An answer to the latter question requires exact knowledge of how factors such as molecular size and polarity affect partitioning into surface cutaneous structures and diffusion through them. Through direct evidence or by analogy with structurally similar compounds, certain cosmetic ingredients such as antimicrobials and organic antioxidants seem chemically well- adapted for cutaneous passage and the skin reac- tions they cause come as no surprise. Manifesta- tions seen with compounds of extreme polar and non-polar natures are generally unanticipated. To clarify this situation, available quantitative data on percutaneous absorption are reviewed with special emphasis placed on the influence of chemical structure on ease of permeation. It is seen that over part of the polarity range of common constituents, the skin (stratum corneum) acts as a lipoidal struc- ture, largely regulating passage on the basis o/w partitioning. Highly polar compounds have also been shown to measurably penetrate the barrier, suggesting that there are significant alternative means of passage. These observations are placed into perspective with respect to cosmetic use and risks. Chlorination studies in human hair Bhupender S. Gupta, Ph.D. and Nancy Fair, North Carolina State University, P.O. Box 5006, Raleigh, NC 27650. The present study examines the effect of chlorina- tion on the physical properties and morphology of human hair. Normal and cosmetically treated hair were chlorinated for a predetermined number of cycles in which parameters such as pH, chlorine concentration and cleansing treatments were varied. The physical property emphasized in this research was the inter-hair friction under low normal forces. A method is described for effec- tively characterizing this property under loads as low as 1-5 grams, which are of the same order as the level of normal combining forces. The changes in morphology were studied with a high resolution scanning electron microscope. Friction values found in chlorinated hair were significantly higher than those in control hair. Chlorination under acidic conditions produced higher values and greater changes in morphology than thos• under neutral conditions. The directional frictional effect (DFE)--a property typical of hair-like fibers-- decreased with most treatments. Examination of morphology, especially along regions of contact, supported the views that the general effects of chlorination were to partially dissolve and destroy

ABSTRACTS 43 the scales and to change the mechanical character of the cuticle from a hard elastic to a soft viscoelas- tic material. These and other important results on hair are discussed in detail. The guinea pig as a model for predicting photoallergic contact dermatitis William P. Jordan, Jr., M.D., Medical College of Virginia, MCV Station, Richmond, VA 23298. This report describes modifications in the tech- nique used for both the induction and elicitation of photoallergic contact dermatitis (PACD) in the guinea pig. These changes have improved the reliability of this animal as the model of choice for screening chemicals or products for their tendency to produce PACD. The induction period consists of 15 exposures of the test substance to shoulder skin that has been abraded with a nylon brush rotating at 13,000 rpm. One hour later, the test site is irradiated with broadband UVA from a source having some irradiance below 320 nm (UVA/b). The animals receive 450J/cm 2 of UVA during the three week induction period. The elicitation (chal- lenge) test is repeated for two consecutive days. Each day, the test material, if a liquid, is applied to two sites every 30 to 60 minutes for six hours then one of the sites receives 20 J/cm 2 of UVA. These photo-induction and photooelicitation procedures have demonstrated that low level concentrations (0.25% range) of 6-methyl coumarin or musk ambrette will both induce and elicit PACD in the guinea pig. This report adds more evidence that the induction of PACD in the guinea pig is dependent on broadband UVA. Studies of the epidermis using fluorescent dyes and cyanoacrylate stripping Peter T. Pugli•se, M.D., Xienta, Inc., 225 Long Ave., Hillside, NJ 07027. The purpose of this study was to develop a simple and inexpensive method of determining both the chemical and morphological characteristics of the epidermis. By adapting existing technology from several fields, a method was developed which employs specific fluorescent dyes which are capa- ble of staining certain selective epidermal proteins. The dyes are first applied to the skin in low concentrations and allowed to dry. A small drop of cyanoacrylate glue is placed on a microscope slide and gently pressed to the dyed surface. After sixty seconds the slide is removed with a peeling motion, carrying away several layers of stratum corneum. Visualization of the preparation with a microscope equipped for fluorescence allows three dimensional viewing of the topography of the skin. Hair follicles, sweat ducts, dermatoglyphs and other surface structures are easily seen. Both the inner and outer surface of the preparation may be viewed by turning the slide over and viewing through the glass to the under surface. Specific stains, such as acridine orange, berberine, and mercurochrome will allow study of the keratin of stratum corneum, nuclei, DNA and RNA, SH and S-S bonds and connective tissue. This technique may be used to demonstrate efficacy of products by taking samples before and after use. The method is applicable to establishing substantivity, cleansing, hydration, and defining certain chemical reactions. New test methodology for observing irritant and allergic reactions Robert L. Reitschel, M.D., Emory University School of Medicine, 215 Woodruff Memorial Bldg., Atlanta, GA. Methods which predict allergic contact dermatitis are many and their utility is proven. Among the more common types of testing procedures are the modified Draize test and maximization test. Irritant reactions are more varied in presentation and include stinging, urticaria, erythemas, and dermati- tis. Evaluation of irritant potential is presently studied by repeated insult patch testing and scarifi- cation. Newer technologies are being investigated in hopes of increasing the reproducibility of the predictive nature of irritancy testing. The swelling behavior of human hair and epidermal membrane Clarence R. Robbins, Ph.D. and K. M. Fernee, Colgate-Palmolive Co., 909 River Rd., Piscataway, NJ 08854. The swelling behavior of hfiman hair and of epider- mal membrane are compared. The results show that the microfibril-matrix models proposed to explain the swelling and extension behavior of wool fiber can also qualitatively account for the swelling behavior of hair and stratum corneum. The outer layers of human skin swell more in thickness than in area, and hair more in diameter than length. This behavior is consistent with the orientation of helical proteins in both substrates. Epidermal membrane is more sensitive than hair is to water, anionic surfactant, or formic acid, but less sensitive to thioglycolic acid. Anionic surfactants produce greater swelling than cationics, with highly specific surfactant-structure effects on the epidermal membrane. These results indicate that the location and immediate environment of bind-