44 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS ing sites in the membrane determine the ability of surfactants to disrupt and to swell the outer layers of skin. We suspect similar directional interactions between hair and different surfactants, but the swelling effects were too small to permit facile measurement with that substrate. PRESERVATIVES Evaluating preservative candidates for suita- bility Thomas E. Haag, Mallinckrodt, Inc., St. Louis, MO 63147. The search for new compounds effective as antimi- crobial agents is an expensive and time consuming process. The fine balance between human toxicity and antimicrobial activity is hard to achieve, thus new preservatives entering the marketplace are few and far between. The search continues, however, for the ideal preservative. Many of the factors to consider in evaluating a new compound are similar to those encountered by formulating chemists choosing a preservative system for new formula- tions. Topics to be discussed include determining antimicrobial activity, stability, partition coeffi- cients, compatibility with formulation compo- nents, toxicity, cost, and registration. Collaborative study of procedures for deter- mining the preservation efficacy of water- miscible mascaras Leo Judge, Ph.D., Saul Tenenbaum, Donald G. Ahern, Ph.D., Kerby Farrington, Ph.D., Joe Madden, Ph.D., John L. Smith, Ph.D. and John Yablonski, Revlon Inc., 945 Zerega Ave., Bronx, NY 1O473. Two different conceptual approaches are in use for the antimicrobial challenge testing of mascaras: in one, the preservation system is challenged by moni- toring the product for a spectrum of microorga- nisms and assaying periodically for microbial survival in the other, the double-membrane chal- lenge procedure, microbial inhibitors from the product diffuse through a micro-layer of water and cause rapid death of the challenge organisms deposited on the surface of a membrane. The present collaborative study was undertaken to compare standardized versions of both procedures. Mascaras prepared by industry to be either adequately, marginally or inadequately preserved were simultaneously challenged by the participat- ing laboratories. The results show the excellent reproducibility and statistical confidence between laboratories using each method and agreement between the two procedures. Microbiological aspects of raw material pres- ervation Peter A. Nielsen, Ph.D., Vick Divisions Research and Development, Mr. Vernon, NY 10553. Raw materials used in cosmetic and toiletry prod- ucts, whether of natural or synthetic origin, may contain micro-organisms or serve as substrates for their growth. The presence of large numbers of organisms is potentially hazardous. The micro- biologist should identify troublesome raw materi- als and recommend corrective measures. Some raw materials are inherently microbiocidal and are thus self-preserving. Others, because of their physical state, will not support growth but may nevertheless contain organisms. If such a microbial load is unacceptably high or includes undesirable micro- bial species, it may be necessary to treat these raw materials with a lethal agent to reduce or eliminate the microbial population. Still other raw materials, such as protein solutions, may not only contain microorganisms but may also serve as culture media for their proliferation. These supportive materials require an added antimicrobial substance to preclude microbial growth. The choice of preservative depends upon the physical properties and chemical nature of the material, and the types of organisms present. The preservative must be compatible with the formulation in which it will be used and active against the spectrum of organisms in the material. It must also be stable as well as nontoxic. An accelerated preservation test ElizabethJ. Scibienski, Ph.D.,JohnJ. O'Neill Ph.D. and Catherine A. Mead, Avon Products Inc., Suffern, NY 10901. An accelerated preservation test (APT) procedure that involves addition of nutrient/buffer salts and glucose to aqueous products has been developed. This test can identify within 7 days: inadequately preserved products marginally preserved products which fail late in a twelve-week double-challenge test with 106 bacteria per gram products that are poorly preserved against fungal spores and which would allow persistence of viable spores. Extensive testing with APT and twelve-week challenge-test procedures have revealed excellent correlation for a wide variety of products (e.g., shampoos, condi- tioners, creams, lotions and water-based make- ups).

ABSTRACTS 45 TESTING COSMETICS & TOILETRIES Use of the raman microprobe in characteriza- tion of organic materials Fran Adar, Ph.D., Instruments SA, Inc., 173 Essex Ave., Metuchen, NJ 08840. The Raman Microprobe-MOLE produced by Instruments SA combines the capabilities of optical microscopy with the ability for chemical and phase characterization. Exploitation of its potential to identify organic as well as inorganic materials, in dtu with 1/zm spatial resolution, will be considered. Examples of applications which enable possible problems in the cosmetic industry to be extrapolated will be selected. Aspects of wax interactions in the formula- tions of cosmetic cold creams David F. Bernstein, Ph.D., Revlon Health Care Group, 1 Scarsdale Rd., Tuckahoe, NY 10707. In the development of original formulas or replace- ment of ingredients in existing cosmetic formula- tions, the art of the formulator can be enhanced by a working knowledge of all physical and chemical data. This is particularly valid with petroleum waxes, as the complexity of the composition of hydrocarbon waxes makes it difficult to utilize typical specifications as the sole basis for substitu- tion. Additionally, the petroleum industry classifies waxes solely by origin and generally disregards the hydrocarbon structure, which provides for nomen- clature inconsistencies. Although this communica- tion is concerned with the performance of petro- leum hydrocarbon waxes in simple cold cream formulations, the findings are applicable to cosmetic formulation in general. The chemical composition of waxes used in conjunction with beeswax was shown to affect finished product viscosity. Waxes with predominantly straight chains (e.g., paraffinic hydrocarbons) yielded high- viscosity products branched chain waxes generally yielded lower-viscosity products. Typical raw mate- rial specifications as would be used in quality control were not sufficient to predict product viscosity, although the congealing point-refractive index relationship could be used as an indicator of the n-paraffinic composition, which was shown to be predictive of product viscosity. The chemistry and formulation properties of sodium Cx4-x6 olefin sulfonates Phillip L. Cotrell, Cyclo Chemicals Corp., 7500 N.W. 66th St., Miami, FL 33166. Sodium C•4_x6 olefin sulfonates (AOS) have been widely promoted in recent years as economical replacements for alcohol and alcohol ether sulfates in shampoo and personal care products. Their excellent performance and physical properties make them quite attractive to formulators who are attempting to develop high foaming, inexpensive systems. Despite the obvious advantages of these compounds, their formulation properties vary substantially from alcohol and alcohol ether sulfates and, therefore, cannot be indiscriminately used as direct replacements for them. To adjust for these variances, formulation modifiers such as fatty diethanolamides or ampholytic surfactants must be added to AOS-based systems to produce aestheti- cally attractive, functional products. This paper summarizes some of the formulation and perfor- mance properties of AOS and describes techniques to prepare optimized shampoo or detergent prod- ucts. The data clearly illustrate the many advan- tages of AOS and point out mechanisms to over- come its potential formulation shortcomings. This paper is a critical examination of AOS and covers specific topics which have not been fully examined in recent publications. Alternate color systems for replacing D&C Red 9 and D&C Red 19 R. Kerry Haines and Jan Rempe, Hilton-Davis Chemical Co., 2235 Langdon Farm Rd., Cincinnati, OH 45237. Potential delistment by the FDA of the certified organic colors, D&C Red 9 and D&C Red 19, has created a need for alternative colors. The range of organic colors in wide commercial use today can be used in various combinations to approximate the shades of these two colors. However, more exacting matches have been developed using certi- fied colors such as D&C Red 27, D&C Red 36, FD&C Yellow 6, and FD&C Blue 1--colors which traditionally have not received much attention by the color chemist. Additionally, manufacturing modifications in the predominantly used colors, D&C Red 6 and D&D Red 7, can broaden their shade ranges from bluehess to yellowhess to provide better options in developing closer color matches. Ideally, the cosmetic chemist needs an exact duplication of shade that can be directly substituted for D&C Red 9 or for D&C Red 19 in existing cosmetic formulas. The specific applica- tion, whether lipstick or powder, and the percent- age level of the color to be substituted will dictate different alternate color systems. Structural analysis by acoustic microscopy Larry W. Kessler, Ph.D. and D. E. Yuhas, Soho- scan, Inc., 530 E. Green St., Bensenville, IL 60106. Acoustic microscopy is a technique which illu- minates a sample with ultrasonic energy and