CORRESPONDENCE Louis Schwartz, M.D. 915 Nineteenth Street, N. W., Washinl•ton 6, D.C. November 5, 1954 Mr. M. G. deNavarre, Chairman Publications Committee JOVRH^L or THE SOCIETY OF COSMETIC CHEMISTS 404 Lothtop Road Grosse Pointe Farms 36, Michigan Dear Mr. aleNavarre: I would like to comment on the article by Dr. Peck in Volume V, Num- ber 2, of T•E JOVRH^L. By far the largest part of the article from page 113 to 124 is a review of material previously published. Much of it, as Peck states, is in the book "CosMETICS AND DERMATITIS," by Schwartz and Peck. From page 124 on to page 126 he comments on the article "Paraphenylenediamine Hair Dyes," ./lrch. Dermatol. and Syphilol., 66, 233 (1952), by Schwartz and Barban. Only two paragraphs on page 126 are observations by himself. There Peck states that: "In every instance of true cases of allergic contact dermatitis due to hair dye which I have studied, they not only gave a positive reaction to the hair dye which they used, but to a 1 or 2 per cent para solution. In order to avoid the primary irritant effect of the ammonia used in the hair dye it has been my habit after applying the test solution to allow it to dry thoroughly on the skin for at least ten minutes before the patch is applied. An open patch test is always used at the same time." The test solution does not "thoroughly dry" on the skin in ten min- utes. He does not state how many "true cases of allergic contact derma- titis due to hair dye" he has studied, and he does not state whether the positive patch test reaction occurred under the covered patch or over the open patch. One would expect to get a positive reaction to a patch test in a case of "true allergy." That is the basis of the pre-use test re- quired by the Food and Drug Administration. He states that, "There are always one or two of the operators who suffer from contact dermatitis from hair dyes .... " He admits this is poor argument to indicate the possible hazard of hair dyes for home use. He gives no data which proves that the beauty parlor operator's contact dermatitis is due to hair dyes. Beauty parlor operators handle many substances which are much more likely to cause dermatitis than are the hair dyes. For instance, shampoos, hair tonics containing alcohol and resorcin, nail lacquers, etc. In addition to this, when the operators handle the hair dyes they wear rubber gloves to prevent the paraphenylenediamine hair dyes from staining their hands, a stain very difficult to remove. This 316

CORRESPONDENCE--LOUIS SCHWARTZ 317 protects the hands from the dye, ammonia, and other compounds in the dye. Many operators do not use gloves when giving shampoos and other non-staining possible irritants. He "believes" that it is only a question of time before continuous use by any one person at home will result in increasing the number of those who are sensitive to paraphenylenediamine and allied compounds. With this observation I cannot entirely disagree because it is possible that by the continued use of any substance--even strawberries, fish, and tomatoes --more people will be sensitized, but the incidence of sensitization today from paraphenylenediamine is so low--1 to 40,000, or less--that even a doubling of this incidence would still make paraphenylenediamine hair dyes as they are manufactured, regulated and used today safe for use because an incidence of 1 case of dermatitis in 20,000 is certainly not alarm- ing and is certainly comparable with the incidence of dermatitis from soaps and even articles of food. Dr. Peck does not take into consideration the fact that many people become even more immune (haMened) by con- tinued use and increased exposure and that improvements in manufacture and use of paraphenylenediamine may further take place and cause a lessening of the incidence of dermatitis, as has happened in the case of indelible lipsticks using fluorescent dyes, nail lacquers, and in the case of the cold wave which when it first came out caused a high incidence of dermatitis. As for his quotation from Harry's book as to the desired properties of an ideal hair dye, which takes up the rest of the article on page 127, no one can disagree with the requisites of such an ideal hair dye, but there is no substance to which someone may not become sensitized and there have been no authentic cases of "systemic" poisoning in humans re- ported from paraphenylenediamine when properly used as a hair dye. Paraphenylenediamine answers all the other requirements given by Harry. Paraphenylenediamine hair dyes today are being used by millions of people in the United States and other parts of the world. The incidence of dermatitis from them is so low that casualty companies will insure at low rates those manufacturing and selling the dyes, provided proof is presented that they have been tested by the "prophetic patch test" or one of its modifications, conducted by a recognized dermatologist. Paraphenylenediamine is the most frequently used fur dye, yet the in- cidence of dermatitis from paraphenylenediamine dyed fur has also greatly diminished. A telephone query to the Medical Director of one of the largest manu- facturers of paraphenylenediamine elicited the statement that "they had not had a case of dermatitis from it, among their workers for as far back as he could remember, over 20 years." The United States Government through its Food and Drug Admin- istration has investigated the possible hazard and incidence of dermatitis from paraphenylenediamine hair dyes and permits them to be sold under existing Federal regulations. All the States are doing the same. The proof of the pudding is in the eating. Truly yours, LovIs SCI•WARTz, M.D. LS/as