PERMANENT WAVING OF HUMAN HAIR: THE COLD PROCESS 121 structure. This obviously is not true. As yet very little is known as to. what role the cuticle, the cortex, and the medulla play in the process of cold waving. Until such time as more data and new experimental tools become available, it seems ad- visable to use the oversimplified concept to further the understanding of the cold wave process. The re- cent publications by Phillips (8), Stoves (11, 17), Lehmann (18), Mercer and Rees (19), Hock and McMurdie (20), and others indicate that the problem of the structure of -keratin fibers as related to their chemical reactivity is receiving more and more attention. Current widespread interest in the toxicological properties of thiogly- colares has revealed the fact that very few experimental data on this subject have been published. It is obvious that neither eloquent editor- ials nor vociferous accusations or denials will lead to the solution of the problem. In private correspondence from clinicians, several of these have stated that they have patients which show "typical" symptoms of thioglycolate poisoning. It is strange that these "typical" symp- toms which one clinician describes, often 3iffer radically from those de- scribed by another clinician. As yet ho authoritative work has been published on the mode of action of thioglycolate on the living organism and on the symtomatology of thio- glycolate poisoning. In this labora- tory, using rabbits as test animals, it was found that it is possible to kill the animals if sufficiently large doses of ammonium thioglycolate are applied percutaneously over a long enough time. When the organs and tissues of animals which had thus succumbed were examined macroscopically and microscopically by a competent pathologist, no pro- nounced changes from the normal controls could be observed. Work now in progress suggests the at- tractive hypothesis that the action of thioglycolates may be to deprive the body of labile methyl groups (from methionine and choline), these being used to detoxify the thiogly- colate. In this connection, it is interesting to note that thiodigly- colic acid, given either percutane- ousl? or orally by stomach tube, seems to be quite well tolerated by experimental animals. Percutaneous.applications of mod- erate amounts of thioglycolates are readily tolerated by experimental animals. Using the Draize tech- nique (21) it was found that the daily application of a commercial cold wave lotion for twenty days in amounts equivalent to 100 mi. per 50 kg. of body weight produced no apparent ill effects on rabbits as evidenced by the growth curve, red and white cell counts, as well as ex- amination of the organs at necropsy. While it is not justifiable to trans- late these findings directly to the human being without further work, they do seem to indicate that the factor of safety is quite large, since only a very small fraction of 100 mi. can possibly be abs6rbed by the patron during a cold wave.

122 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS Patch test studies using the Schwartz and Peck method (22) have shown that the incidence of sensitization to cold waving lotion is quite small, and that when the concentration of thioglycolate is kept below 1 N, the danger of'pri- mary irritation is negligible. More than 400 patches were applied to employees, some of whom come in contact with thioglycolates daily, while others have come into con- tact with the material only occa- sionally, and •till others had never been exposed to it before. Out of this relatively large series, only one definite positive (+) response has been obtained. BIBLIOGRAPHY 1. Schnitzler, A.,"Theode und Hilfsmittel des Dauerwellens" Verlag fiir Chemische Industrie H. Ziolkowsky• Augsburg, Germany (1936). 2. Neville, H. A., and Harris, M., 5tour. Research Nat. Bur. Stand., 1•t, 765 (1935). 3. Steinhardt, J., Fugitt, C. H., and Harris, M., Ibid., 25, 519 (1940). 4. Speakman, J. B., and Elliott, G. H., Proc. Sym. Fibrous Proteins, Univ. Leeds (May, 19•,6). 5. Sullivan, M. X., _publ. Health Rep. U. 8._P.H.S., 41, 1030 (1926) 44, 1421 (1929). '. 6. Sanford, D., and Humoller, F. H., •tnalytical Chem. (in press). 7. Sookne, A.M., and Harris, M., your. Research Nat. Bur. Stand.• 19, 5.35 (1937). 8. Phillips, H., _proc. Syrnp. Fibrous Pro- teins, Univ. Leeds (May, 1946). 9. Bull, H. B., and Gutmann, M., 5t.-4. C.S., 66, 1253 (1944). 10. Jones, C. B., and Mechan, D. K., •trch. Biochern., 2, 209 (1943) 3, 193 (1943-1944). 11. Stoves, J. L., Trans. Faraday Soc.• 38, 501 (1942). 12. Rutherford, H. A., and Harris, M., SCour. Research Nat. Bur. Stand., 20, 559 (1938). 13. Rutherford, 59H3 A., and Harris, M., Ibid., 23, (1939). Cf. Harris, M., and Smith, A. L., Ibid., 20, 563 (1938). 14. Lemin, D. R., and Vickerstaff, T., Proc. Symp. Fibrous Proteins, Univ.. Leeds (May, 1946). 15. Blackburn, Middlebrook, and Phillips, Nature, 150, 57 (1942). 16. Rykland, L. R., and Schmidt, C. L. A., Univ. Calif. _publ. _physioL, 8, 257 (1944). 17. Stoves, J. L., _proc. Royal Soc. Edin- burgh B, 62, 132 (1945). 18. Lehmann (Wolfen), E., KoL Zeitsch., 108, 6 (1944). 19 Mercer, E. H., and Rees, A. L. G.• •tustralian 5 e. ExptL BioL Med. Sci., 24, 147 (1946). 20. Hock, C. W., and McMurdie, H. F., 5eour. Research Nat. Bur. Stand., 31, 229 (1943). 21. Draize, J. H., Woodard, G., and Cal- very, H. O., 5eour. _pharm. and Exp. Therap., 82, 377 (1944). 22. Schwartz, L., and Peck, S. M., _Pub. Health Rep. U.S._P.H.S., 59, 546 (1944).