MEASUREMENT OF ODORS IN COSMETICS 11 present in cosmetics of any kind can be tested and measured im- mediately after manufacturing and also after various periods of aging and storage. Therefore, the manu- facturers have at their disposal numerical data that can be kept for further reference and compared at any time. This is most valuable when comparison is involved with new and old formulas, more or less aged batches, or competitive brands of various strengths. Such measurements make possible the study of combinations of odors that often occur during the mixing or aging of various cosmetics. Finally, it is the only method for actually measuring the fixative properties of musk and similar products. All cosmetics should be tested with the Osmometer and their odors measured. Among the solid cos- metics we will mention mascara, face powders, cake soaps, lipsticks, cake make-up, hemostatic cakes, rouge, and foot powders. Among the liquid preparations are kohl, eye lotions, face lotions, shampoos, detergents, hair lacquers, hair dyes and bleaches, hair tonics, hair rinses, cold wave lotions, dentifrices, mouth washes, nail polishes, cuticle soften- ers, after shave lotions, sun tan lotions, deodorizers, antiperspirants, hand lotions, leg make-up, and per- fumes, to which can also be added tooth pastes and shaving creams. The tests are conducted on weighed samples of a size inversely proportional to the intensity of the odor. When essential odors and concentrations of perfumes are con- sidered, it is amazing to realize the small amount that has to be used in the Osmometer to obtain a quick determination of the odor threshold number. Scores of odor measure- ment tests conducted on cosmetics have established the fact that there are great variations between various samples, and various similar prod- ucts, in the retained intensity of odor after various periods of time. They have also established that such differences could not very well be found by other methods. This also applies to the retained odors of fixatives and to the ratio of the per- fume odor and fixative odor. PACKAGING MATERIALS This short study would not be complete without mentioning the odor measurements conducted on packaging materials used for cos- metics. Odor measurements are very important because the protec- tion of the packaging material should work two ways first, the retention of odor inside the package, and second, the prevention of out- side odors penetrating the package. You certainly realize the impor- tance of the imperviousness to odors of packaging materials in the cos- metic industry and of the retention of odors of these materials when precious odors have to be retained in products such as cake soaps, face powders, detergents, lipsticks, foot powders, and cosmetics which are generally wrapped and packed in such materials as paper board, card- board, and plastics, whose stanch- ness is not always easily obtained.

12 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS CONCLUSION There are many other uses of the Osmometer which have not yet been perfected or even tried. We have mentioned only the applica- tions for which we had the greatest number of requests, and in which our staff has ac•tuired a recognized experience. The demonstrations which will follow will prove to you that its use is simple, and that any- body in good health and with a normal sense of smell can use it. Any beginner is able to measure odors of great intensity with a rela- tive approximation. However, in order to measure odors of small intensity and to make comparative examinations, it is necessary to have a scientific and progressive training in the use of the apparatus. From our experience we have found that a methodical training of about six months is required to enable a technician to make all kinds of odor measurements and comparative studies with great accuracy. This is not a long period of training when one realizes that nobody can meas- ure odors all day long and continue to obtain accurate results. There should be sufficient rest periods be- tween various measurements in order to obtain reproducible results, and of course this applies as well to the training period as to the normal periods of use after training we would say that it is even more im- portant during the training period, as the beginner feels much more fatigue after a few odor measure- ments than the seasoned Osmometer technician. As an interesting feature of the use of the Osmometer, we like to mention that we never saw a case yet where the practice in its use had been forgotten at any time, even after relatively long periods of in- activity, such as vacations, illness, etc. Those who have had training in the use of the Osmometer are also able at any time to obtain results that can be compared with those of any other trained technicians. Consequently, it can be said that to the cosmetic chemist the Osmom- eter is a most useful apparatus. In no other industry does it have as many applications as in the manu- facturing of all kinds of perfumes and cosmetics. It is indispensable in laboratory research and produc- tion control of deodorants. It is also useful in the evaluation of the O.T.N. of Samples Sample Alone O. T. N. of Samples and O.T.N. of Control Samples q- Odor Perspiration Perspiration Removed Deodorant No. 1 6.2 21.3 8.3 13.0 Deodorant No. 2 6.0 21.1 7.9 13.2 Deodorant No. 3 7.9 23.0 10.7 12 3 Deodorant No. 4 6.5 21.6 7.2 14.4 Deodorant No. 5 6.5 21.6 7.5 14.1 Deodorant No. 6 8.3 23.4 11.3 12.1 Control perspiration alone-- no sample 15.1 .... 0.0