STABILITY TESTS ON MAKE-UP ITEMS 303 Bactericidal Actions of Some Mercurial Compounds on Hemolytic Strepto- cocci," •.A.MA., 136, 3641 (1948). (5) Klarmann, E.G., and Wright, Eleanor S., "Are Quaternary Ammonium Com- pounds Sporicidal?," Am. 5 •. Pharm., 122, 330-336 (1950). (6) Blank, 1. H., "Degerming the Cutane- ousSurface, 1. Quaternary Ammonium Compounds," •. Investig. DermatoL, 15, 249-256 (1950). (7) Price, P. B., and Bonnett, Alberta," "The Antibacterial Effects of G-5, G-11, and A-151 With S•pecial Reference to Their Use in the Production of a Germi- cidal Soap," Surgery, 24, 542-554 (1948). (8) Kelner, Albert, "Revival by Light," Sci. dm., 184, 22-25 (May, 1951). (9) Flett, L. H., Haring, R. C., Guiteras, A. F., and Shapiro, Rebecca L., "The Revival of Organisms Presumably Killed by Phenol," •. Bacteriol., 50, 591-595 (1945). (10) Price, P. B., "Reevaluation of Ethyl Alcohol as a Germicide," alrch. Surg., 60, 492-502 (1950). STABILITY TESTS ON LIPSTICK, FACE POWDER, AND MAKE-UP ITEMS* By H. HEINRICH, PH.D. Kolmar Laboratories, _inc., Milwaukee, [d/is. STABILITY TESTS for the pur- pose of this talk will be defined as tests made in the laboratory to guarantee stability while the prod- uct is in the stores and in the hands of the ultimate consumer. In this sense we may speak of stability tests as tests which assure the sal- ability of a product over an extended period of time. Everybody fully realizes that the requirements of salability vary and that every day standards become more rigid what constituted salability some years ago, may not constitute salability now. Let's assume that we have de- veloped a new product in the lab- oratory. We have made enough consumer tests to be sure that it is a desirable product. So the next step is to get into production. * Presented at the May 18, 1951, Meeting, New York City. We realize, at once, that our experi- ence with this new product is, after all, limited and we do not know whether the product would stand up under the conditions encountered in the stores and homes. We know from past experience approximately what conditions are encountered dur- ing shipping, storing, displaying, and use. We know, for instance, that a shipment during the winter months may encounter temperature varia- tions of some 70øF in addition to con- tinued jolting and rough treatment during shipment. In storage, the cosmetic may be on a shelf for a year or longer because of the habit of some storekeepers of picking up the nearest package regardless of age. We, furthermore, know that a cos- metic may be displayed in showcases under hot lights and the tempera- tures may go as high as 120øF. The consumer may leave the cosmetic

STABILITY TESTS ON MAKE-UP ITEMS 303 Bactericidal Actions of Some Mercurial Compounds on Hemolytic Strepto- cocci," •.A.MA., 136, 3641 (1948). (5) Klarmann, E.G., and Wright, Eleanor S., "Are Quaternary Ammonium Com- pounds Sporicidal?," Am. 5 •. Pharm., 122, 330-336 (1950). (6) Blank, 1. H., "Degerming the Cutane- ousSurface, 1. Quaternary Ammonium Compounds," •. Investig. DermatoL, 15, 249-256 (1950). (7) Price, P. B., and Bonnett, Alberta," "The Antibacterial Effects of G-5, G-11, and A-151 With S•pecial Reference to Their Use in the Production of a Germi- cidal Soap," Surgery, 24, 542-554 (1948). (8) Kelner, Albert, "Revival by Light," Sci. dm., 184, 22-25 (May, 1951). (9) Flett, L. H., Haring, R. C., Guiteras, A. F., and Shapiro, Rebecca L., "The Revival of Organisms Presumably Killed by Phenol," •. Bacteriol., 50, 591-595 (1945). (10) Price, P. B., "Reevaluation of Ethyl Alcohol as a Germicide," alrch. Surg., 60, 492-502 (1950). STABILITY TESTS ON LIPSTICK, FACE POWDER, AND MAKE-UP ITEMS* By H. HEINRICH, PH.D. Kolmar Laboratories, _inc., Milwaukee, [d/is. STABILITY TESTS for the pur- pose of this talk will be defined as tests made in the laboratory to guarantee stability while the prod- uct is in the stores and in the hands of the ultimate consumer. In this sense we may speak of stability tests as tests which assure the sal- ability of a product over an extended period of time. Everybody fully realizes that the requirements of salability vary and that every day standards become more rigid what constituted salability some years ago, may not constitute salability now. Let's assume that we have de- veloped a new product in the lab- oratory. We have made enough consumer tests to be sure that it is a desirable product. So the next step is to get into production. * Presented at the May 18, 1951, Meeting, New York City. We realize, at once, that our experi- ence with this new product is, after all, limited and we do not know whether the product would stand up under the conditions encountered in the stores and homes. We know from past experience approximately what conditions are encountered dur- ing shipping, storing, displaying, and use. We know, for instance, that a shipment during the winter months may encounter temperature varia- tions of some 70øF in addition to con- tinued jolting and rough treatment during shipment. In storage, the cosmetic may be on a shelf for a year or longer because of the habit of some storekeepers of picking up the nearest package regardless of age. We, furthermore, know that a cos- metic may be displayed in showcases under hot lights and the tempera- tures may go as high as 120øF. The consumer may leave the cosmetic