276 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS It may be presumed that fatty acids are adsorbed to anion exchangers, ammonia to cation exchangers and indole to either of these two. That this assumption holds was shown by the experiments mentioned. In human secretions there may be many other substances producing odor. But the experiments with feces, etc., indicate that such substances, if there are any at all, can be taken up by adsorption and turned scentless when ion ex- changers are correctly used. Effective ion exchange resins may successfully be used for the abolish- ment of osmidrotic odor. For manufacturing preparations of practical use, nonionic substances with high surface activity are suitable to use as vehicles. In recent experiments observing the activity of cation exchange resins mixed with various bases, Jurist concluded that hydrophile or water soluble vehicles are superior to petrolatum base in rapidity of ion exchang- ing. Though this is confirmed by the results of the experiments on sub- jects above mentioned, it is also regarded that petrolatum, a hydrophobic base, is helpful to lengthen the adhesion'to the skin. The mechanism of deodorant action of ion exchangers may be interpreted as follows: (1) Purified ion exchange resins are not soluble in water and have no astringent action as is the case with aluminum salts. Prevention of sweat secretion is therefore not the cause for deodorization of the ion exchangers. (2) It has recently been demonstrated by Shelley, Hurley and Nichols that human apocrine sweat is odorless and sterile when it initially appears on the skin surface and that its acrid odor is only developed by the action of micro•Srganisms. They have also succeeded to prevent odor from development on the axilla for more than eighteen hours by mechanical cleansing and washing with antiseptics. There are several reports con- cerning the antiseptic and bacteria-adsorbing actions of ion exchange resins. One may therefore imagine that the deodorant effect of the ion exchangers is partly due to its germicidal action. In the experiments of Shelly, et al., however, it has been demonstrated that the antiodorant effect of antiseptics is decidedly less in vivo compared with the in vitro experiments, even when they used highly active antiseptics. It seems therefore plausible to conclude that deodorization by the antiseptic action of ion exchangers is little if there is any at all. (3) According to Thurmon and Ottenstein, pH of sweat over the skin may be kept normal for a long time when ion exchangers are used. The growth of bacteria over the skin may be promoted by changes in pH of the sweat and it may therefore be thought that deodorization by ion exchangers is helped by their action keeping pH normal. But from the above consider- ation with regard to the antiseptic action, it seems certain that this mecha- nism is of little significance. (4) From the above account, it may be concluded that the deodorant

1955 SEMINAR DISCUSSION 277 effect of the ion exchangers results almost exclusively from adsorption of odoriferous substances onto the ion exchangers. EmL G. KLARMANN (Lehn & Fink Products Corp., New York, N.Y.) (1) Concerning the relationship between protein precipitation and antiperspirant action: The capacity for protein precipitation is not the sole basis of the anti- perspirant mechanism. The current controversy should not revolve around the assertion or negation of any true antiperspirant effect which, in fact, appears to be a matter of degree. Dr. Shelley's experiments indi- cate a possibility of complete anhidrosis, probably by poral occlusion. The experiments of Dr. Sulzberger and his associates show that aluminum sulfate creams produce no such closure, but that they cause reduction of the perspiratory flow which is attributed to certain changes in the sweat duct. The two factors are not considered to be mutually exclusive. It is conceivable that one might obtain some single effect or a combination of effects depending upon the type and concentration of the aluminum salt, the duration of contact, the frequency of application, etc. (2) While not a proponent of chlorophyll, I would like to ask why this substance could not change the composition of apocrine sweat so as to pre- vent malodorous decomposition by bacteria. Sodium copper chlorophyllin is bacteriostatic therefore, if brought in direct contact with apocrine sweat under the proper conditions, it will most likely prevent its bacterial decomposition. However, the required concentration of the bacteriostatic substance is so high that 12nder normal conditions of usage, one would produce discoloration of the skin and of the garment touching it. (3) If chlorophyllin is taken internally, why could it not act on metab- olites so that the bacteria could not produce an odor? Reference was made to the deodorization by chlorophyllin of fecal mat- ter. Here the presumption is that if the chlorophyllin is not broken down while passing through the gastro-intestinal canal, it will maintain a con- tinuous inhibitory contact with material of potential decomposition, thereby reducing the intensity of malodor. However, in the case of apo- crine sweating, there is no reason to believe that following oral ingestion of chlorophyllin direct absorption will take place from the gastro-intestinal tract in such a manner as to make something appear in the apocrine sweat, unless that "something" enters circulation first it has never been demon- strated that either chlorophyllin, or any antibacterial conversion or degra- dation product of it, passes into circulation,