132 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS very likely convert all red, blond and brown haired individuals to complete platinum blonds. It might ultimately convert them all to brunettes. Since the melanocytes of the skin do not contain a pheomelanin system, there would be no effect on skin color. Bleaching of dark hair would involve blocking the tyrosinase system. The melanocytes of the skin contain the same enzyme and there would be an excellent chance of altering skin color. In two patients with guanofuracin depigmentation the eye- lashes became white but not the eyelids (17). In only twenty-seven per cent of the cases did depigmentation of the eyelids and eyelashes appear at the same time (19). There is a differential in the sensitivity, not well defined, between the hair melanocyte and the skin melanocyte. These reactions are so far beyond our basic knowledge that the only way to find out what will happen is to try it. In light of past experience future chem- icals will probably produce more surprises. SUMMA RY The hair pigment is more complex than has been assumed. Dark hair contains melanin it is a good assumption that blond, red and light brown hair contains pheomelanin and there is a slight possibility that red hair also contains trichosiderin. The control of hair pigment is extremely complex and mostly a mystery. The theoretically perfect bleach, i.e. cessa- tion of pigment formation in all hair is scientifically possible. Practicality of this reaction awaits evaluation. REFEKENCES (1) Zimmerman, A. A., and Becker, S. W., Jr., "Illinois Monographs in Medical Sciences," Vol. 6, No. 3, Urbana, Univ. of Illinois Press (1959). (2) Chase, H. B., "Biology of Hair Growth," Montagna, W., and Ellis, R. A., editors, New York, Academic Press, Inc. (1958), p. 229. (3) Barnicot, N. A., and Bitbeck, M. S. C.,Ibid., p. 329. (4) "Pigment Cell Biology," Gordon, editor, New York, Academic Press, Inc., (1959), p. 549. (5) Lerner, A. B., and Fitzpatrick, T. B., Physiol. Revs., 30, 91 (1950). (6) Fitzpatrick, T. B., and Kukita, A., "Pigment Cell Biology," Gordon, editor, New York, Academic Press, Inc. (1959), p. 489. (7) Commoner, B., Townsend, J., and Pake, G. E., Nature, 174, 689 (1954). (8) White, L. P., Ibid., 182, 1427 (1958). (9) Alving, A. S., Eichelberger, L., Craige, B., Jones, R., Whorton, C. M., and Pullman, T. N., 5 t. Clin. Invest., 27, 60 (1948). (10) Saunders, T. S., Fitzpatrick, T. B., Seiji, M., Brunet, P., and Rosenbaum, E. E., 5 t. In- vest. Dermatol., 33, 87 (1959). (11) Butenandt, A., Biekert, E., and Linzen, B., Z. physiol. Chem., 305, 284 (1956). (12) Butenandt, A., Keck, J., and Neubert, G., Ann., 602, 61 (1957). (13) Butenandt, A., Biekert, E., and Neubert, G., Ann. 602, 72 (1957). (14) Rothman. S., and Flesch, P., Proc. Soc. Exptl. Biol. Med., 53, 134 (1943). (15) Fitzpatrick, T. B., Brunet, P., and Kukita, A., "Biology of Hair Growth," Montagna, W., and Ellis, R. A., editors, New York, Academic Press, Inc. (1958), p. 255. (16) Van Scott, E.,Ibid., p. 441. (17) Yamada, M., 5tapan. 5 t. Dermatol., 66, 435 (1956). (18) Pinkus, H., A.M.A. Arch. Dermatol., 82, 263 (1960). (19) Kobori, T., and Yamada, M., personal communication.

PROPERTIES OF PEROXIDE-BLEACHED HAIR By WALTER W. EDMAN and MAX E. MARTI* Presented September 15-16,1960, Seminar, Chicago DAMAGE OCCURRING from the bleaching of hair has largely been a subjective response. This paper, sponsored by Becco Chemical Division, Food Machinery and Chemical Corporation, deals with objective physical and chemical changes that occur in hair treated with hydrogen peroxide. The bleaching or lightening of human hair has been widely practiced. Only within the last few years has anything been published about the physical and chemical changes resulting from bleaching hair. Although much has been published about the effect of oxidizing agents on wool, it is not very useful, since there are important chemical and physical differences between hair and wool. Moreover, differences in the mode of treatment and final end use of wool make many findings on wool partially or com- pletely irrelevant to those for which we look in human hair. It has been reported many years ago that after a strong oxidizing treat- ment with hydrogen peroxide, sulfuric acid can be detected in such bleach solutions (1). Harris and Smith (2) have done extensive work on wool and they found that, after up to three hours in 3 per cent hydrogen per- oxide at 50øC., no severe damage could be seen. According to them the sulfur content stays constant whereas the nitrogen content decreases. By increasing the peroxide concentration or the treatment time, the sulfur content decreases also. It is assumed that oxidation products (3) are formed as intermediate products (RSO=--SO=R, etc.) which are not stable in aqueous solutions, and decompose to sulfonic-, sulfinic- and cysteic acids. Therefore, they concluded that hydrogen peroxide attacks the disulfide linkages in wool. E16d and co-workers (1) have shown that wool dissolves in 3 per cent H=O2 at 60øC., pH 4, after eighteen hours, and concluded that this was due to the attack of HsOs on the peptide bonds. If disulfide- and peptide linkage breakdown occurs in wool when treated with H20=, are there also similar linkage breakdowns in human hair during HsO= treatments ? In answering this important question, several tests and methods have been chosen. The measurement of the tensile strength of the fiber, con- * Evans Research and Development Corp., New York 17, N.Y. 133