PSEUDOMONAS CEPACIA ADAPTABILITY 203 The answer to whether or not preservative resistance was retained is shown in Table III. In this Gradient Plate Test, the inocula consisted of(a) the organisms in the formula, (b) Table III Gradient Plate Results: Contaminated Sample Versus Isolated Culture Organism Source Inoculum Formaldehyde MIC Sample Containing Formulation 125 No preservative 1 Transfer 92 12 Transfers 90 Sample Containing Formulation 220 100 ppm formaldehyde 1 Transfer 290 12 Transfers 290 Sample Containing Formulation 330 50 ppm formaldehyde 1 Transfer 320 12 Transfers 320 the isolate transferred once (Tryptic Soy Agar slants), and (c) the isolate transferred twelve items. The resistance was retained through twelve transfers outside the product. SUMMARY These studies have demonstrated the adaptability of P. cepacia. It not only could survive and grow in a hostile environment of pH 3.2, but it could also survive and become resistant to two unrelated preservative systems. Moreover, it would appear that once resistance is acquired it is retained, even when the organism is transferred to laboratory culture media. REFERENCES (1) W. Schaffner, G. Reisig, and R. A. Verrall, Outbreak of Pseudomonas cepacia infection due to contaminated anaesthetics, The Lancet, 1050-1051 (1973). (2) S. G. Geftic, H. Heymann, and F. W. Adair, Fourteen-year survival of Pseudomonas cepacia in salt solution preserved with benzalkonium chloride, Applied and Environmental Microbiology, 37 (3), 505-510 (1979). (3) L. A. Carson, M. S. Favero, W. W. Bond, and N.J. Petersen, Morphological, biochemical, and growth characteristics of Pseudomonas cepacia from distilled water, Applied Microbiology, 25 (3), 476-483 (1973). (4) J. C. Curry, Gradient plate procedure for rapid screening of antibacterials. Presented at 52nd Annual Meeting Proc., Chemical Specialties Manufacturers Association. (Copies available from author, upon request.) (5) J. C. Curry and W. V. Dudley, [IS Patent No. 3,455,788 (1969).

J. Soc. Cosmet. Chem., 34, 205-212 (July 1983) Set relaxation of human hair PENELOPE DIAZ and MICHAEL Y. M. WONG, Ph.D., Clairol Incorporated, Stamford, CT 06922. Received November 3, 1982. Presented at the SCC Annual Scientific Meeting, New York, NY, December 2-3, 1982. Synopsis Although hair can be effectively set by water, heat, or both, such temporary sets do relax over time. It has been found that the set relaxation process can be adequately described, over a wide range of humidity, by the following expression: Y = AT B, where Y is the amount of set remaining after exposure to humidity for a period of time T, with A and B being constants. These constants, which are characteristic of the set relaxation process, are readily calculated from least square analysis of experimental data. The integrated form of the equation, defined as holding power (Hp), and the "half-life" time constant (T50) are shown to be useful parameters for evaluation of setting efficacy. INTRODUCTION Hair styling frequently requires that the hair fibers be set or shaped into a new configuration. Of the several techniques available for such a purpose, heat and water setting are most widely used. Their main appeal is convenience, even though hair set this way tends to relax fast if not assisted by a hair spray. While there have been several reports (1-4) dealing with various aspects of the methodology of set impartation, little or no quantitative information is available regarding the pattern of set decay. The purpose of this paper is to evaluate the behavior of set hair and to suggest some useful approaches for a general quantification of the data. EXPERIMENTAL SETTING OF HAIR SWATCHES Swatches were prepared from Caucasian brown hair purchased from DeMeo Brothers of New York City. Each hair swatch, crimped at the root end, weighed 2g and measured 6 inches long. Before setting, the hair samples were shampooed and thoroughly rinsed. In water setting, the hair was first wet with water and then wound onto a Teflon roller having a diameter of 1.5 cm. While still on the roller, the hair was dried at 50øC for 90 205