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j. Soc. Cosmet. Chem., 33,407-420 (December 1982) Cosmetic analytical chemistry--coming of age IRA E. ROSENBERG, Clairol Incorporated, 2 Blachley Road, Stamj•rd, CT 06922. Received October 28, 1982. INTRODUCTION The last 10 years have seen a rapid growth in both the activity and the importance of the analytical laboratories in the cosmetic industry. Two factors seem to have spurred this change. The first has its base in the increased types of raw materials available to cosmetic chemists. The fact that the 3rd Edition of the C.T.F.A. Ingredient Dictionary now contains 3,400 entries is a poignant reminder of progress in this area. The second has roots in the diversity of the analytical tools with which cosmetic laboratories are equipped nowadays. Advanced instrumentation coupled with microprocessor technol- ogy has allowed the researcher to probe more critically into the quality of supplied raw materials and formulated finished products. Techniques such as nuclear magnetic resonance spectroscopy (NMR), high pressure liquid chromatography (HPLC), mass spectroscopy (MS), and capillary gas chromatography (CGC) are standard equipment in many cosmetic laboratories. The influx of computers has given the analytical chemist greater flexibility in data acquisition and their evaluation and interpretation. Raw data can be stored and manipulated at will, yielding more extensive information per experimental run. Introduction of these instruments has also brought an increase in analytical sensitivity. Ten years ago, routine analysis or structure elucidation required milligram to gram quantities of sample. Today, nanogram to microgram quantities are needed to obtain the same information. There has been a visible impact on the more traditional analytical tools, such as ultraviolet, visible, and infrared spectroscopy. Data stations now interface with these spectrometers, supplying computer assisted interpretation of data. Libraries of spectra are available which can be interfaced with the instruments and recalled at will for comparison with freshly generated spectra. A transformation of cosmetic analytical chemistry is emerging in all areas of the industry, from basic research to quality control. The purpose of this review is to elaborate on the current trends in the use of advanced instrumentation and on the analysis of important cosmetic raw materials such as surfactants, cosmetic preservatives, fragrances, etc. 4O7