ABSTRACTS 327 importance as chemical raw materials. Sucrose esters, for instance, are historically known for their non-toxic, non-irritating, and rapid biodegradable properties. The reluctance to the use of sucrose esters in the manufacture of cosmetics in early days was due to the risk of contamination by the residual solvent dimethyl formamide. New solvent-free su- crose and glucose esters are described. The paper also covers studies on moisturizing and emolliency properties of sucrose esters. Further, sucrose esters and their blends with sodium lauryl sulfate, sodium laureth sulfate, and quats are studied in detail to establish the anti-irritant properties of sucrose esters with optimum performance. Finally, in vitro and in vivo studies are presented to explore the non-de- gressing properties of sucrose esters. SESSION G CONSIDERATIONS IN THE FORMULA- TION OF COSMETICS Microbiological considerations in cosmetic for- mula development and evaluation D. S. Orth, Ph.D., The Andrew Jergens Company, 2535 Spring Grove Avenue, Cincinnati, OH 45214 The microbiological considerations in cosmetic for- mula development begin with a microbiological risk assessment of raw materials and a review of for- mula components to determine their influence on preservative requirements. Factors to consider in se- lecting preservatives and the preservative efficacy test method are presented. The linear regression method of preservative efficacy testing is useful for obtaining decimal reduction times (D-values) for test organisms in cosmetic products, screening tests, stability studies, and product abuse experi- ments. The principles of preservative efficacy testing and method validation are discussed. The microbiological considerations of in vitro and in vivo testing are presented. Microbiological control of manufacturing operations is obtained by adherence to process validation guidelines to insure that the product meets acceptance criteria for microbial limits and is in compliance with governmental re- quirements. Preformulation and formulations of disperse systems Jonas C. T. Wang, Ph.D., Johnson & Johnson Baby Products Company, Grandview Road, Skillman, NJ 08558 Only those disperse systems intended for topical ap- plication will be discussed in this presentation. The paper will give an overview of the theories and basic principles pertinent to the disperse systems, and also the developing sequence of preformulation and for- mulations studies. The purpose of preformulation studies is to gather pertinent physicochemical and biological data which permit the rational develop- ment of stable, safe, and efficacious topical formu- lations. Characteristics of the actives and/or vehicle ingredients which may affect the performance of the topical dosage form, the biological availability, or clinical efficacy of the actives should be evaluated frequently during the preformulation stage. The physicochemical properties of active ingredients in- clude solubility, pka, partition coefficient, pH deg- radation rate profile, and effects of external factors (light, RH, and 02). The formulation optimization includes the factors affecting the formulation per- formances, e.g., cosmetic elegance, emulsification stability, phase-volume ratio, viscosity or consis- tency, etc. Factors affecting the bioavailability of topical formulations are assessed by volatility and transepidermal water loss determination in vitro re- lease and skin penetration studies and an in vivo clinical efficacy test. Ingredients which might po- tentially affect the safety parameters, i.e., irrita- tion, sensitization, and allergic reaction, will also be briefed in the presentation. Aerosols: The system of choice for cosmetics John J. Sciarra, Ph.D., and Anthony J. Cuties, Ar- nold & Marie Schwartz College of Pharmacy & Health Sciences, Long Island University, DeKalb Ave, Brooklyn, NY 11201 Aerosols have been used for cosmetic products since the early 1950's and to date include such product categories as perfumes and colognes, hair sprays, deodorants and antiperspirants, hair mousse, various cosmetic creams and lotions, shave foams, and a host of other cosmetic products. Recent years have seen the emergence of a new "high tech" which is applicable to the aerosol system and cos- metics. While the basic solution, suspension, foam, and semi-solid systems remain basically unchanged, new propellants and components are now being uti- lized along with active ingredients which are highly sophisticated and border on the edge of "phar- maceuticals." This, coupled with the fact that the propellants of the past--namely, dichlorodiflu- oromethane (Propellant 12), trichloromonoflu- oromethane (Propellant 11) and dichlo- rotetrafluoromethane (Propellant 114)--can no longer be used and will no longer be available, has resulted in the development of alternatives. Envi- ronmentally acceptable propellants such as di- methyl ether, Propellants 22, 142, and 152, and several others in various stages of development have been shown to be viable alternatives to the saturated fluorocarbons used in the past. These propellants, along with hydrocarbons and compressed gases, represent the propellants available to the cosmetic formulator of aerosol products. Previously discarded or poorly utilized systems are also being used at this

328 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS time since reasons for their past rejections (such as price, poor performance, etc.) are no longer valid. Compartmental containers and similar systems rep- resent a system that falls into this category. The role of stability testing in pre-formulations and formulation of cosmetic products Donald E. Cadwallader, Ph.D., Department of Pharmaceutics, College of Pharmacy, University of Georgia, Athens, Georgia A well planned stability and formulation screening program during the formulation phase of product development can aid in the efficient selection of the proposed cosmetic product and its package and ap- proximation of shelf life. Accelerated stability studies and factorial design for analyzing different formulation variables may serve as efficient proce- dures for screening and evaluation purposes how- ever, their usefulness is limited because of the com- plexity of cosmetic product formulations. Design considerations, stability protocols, and screening procedures will be presented for specific cosmetic formulations. The role of antioxidants in skin immune reac- tions Lawrence A. Rheins, Ph.D., Richard Moravec, Mi- chael L. Nordlund, Linda S. Trinkle, and James J. Norlund, University of Cincinnati College of Medi- cine, 231 Bethesda Avenue, Cincinnati, OH 45267 (L.A.R., R.M., M.L.N., L.S.T., J.J.N.), and The Procter & Gamble Company, Ivorydale Technical Center 5299 Spring Grove Avenue, Cincinnati, OH 45217 (L.A.R.) Earlier studies from our laboratory demonstrated that topical application of common parasubstituted phenols (PSP) (i.e., monobenzyl ether of hydro- quinone), butylated hydroxytoluene, and butylated hydroxyanisole, ingredients commonly found in medications and cosmetics, can markedly increase the density (cells/mm 2) and/or enhance expression if Ia + Langerhans cells (LC) (i.e., epidermal immune macrophages). These same compounds exacerbate allergic contact dermatitis (ACD) in mice. Further, these effects can be duplicated using a biologically relevant molecule arachidonic acid (AA). The cur- rent studies were performed to determine if changes in LC density and Ia + marker expression following PSP and AA exposure correlated with using more precise in vitro techniques i.e., fluorescent-acti- vated cell sorting (FACS). FACS analysis demon- strated a significant increase in LC density and changes in IA+ marker expression. Our results suggest FACS technology may prove useful in as- sessing subtle changes in skin immune cells, and thereby serve as a useful model for assaying ACD to cosmetics or other dermatological preparations.