118 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS I must emphasize that it is not enough to limit the amount or concentra- tion of estrogen in the cosmetic it is also important to tell the woman how much of that cosmetic she might use with impunity by limiting her to a three-ounce supply for a month's time, we prevent her from smearing the cosmetic all over her whole anatomy outside or maybe even inside and, thus, getting such large amounts of hormone into her circulation which may be- come biologically effective in a systemic way. With these criteria and these precautions, however, the cosmetic use of estrogen is entirely harmless. The first estrogenic cosmetic called Endocreme was my own brainchild and was introduced in the late 1930's. A medical article was published which accused this cosmetic of being a potential carcinogen. The editorial offered no evidence. I shall not discuss the plausible motives of this pe- culiar editorial which started a litigation, later settled out of court. The fact remains that no evidence was ever offered to show that estrogen ap- plied topically to the skin can produce cancer either in humans or in animals. There is not a single case on record after twenty years of use of estrogenic cosmetics. It is a fact, however, that under certain circumstances estro- gens are capable of producing cancer in animals. That statement itself sounds frightening, but if you extend your information a little bit further you find that we are dealing with a bird of an entirely different plumage. First of all, the experiments in wtdch cancer was produced by estrogen were limited to mice and not only to mice in general but to a special highly inbred strain of mice which have a high spontaneous incidence of mammary cancer. In this special breed of mice, the application of estrogen by injec- tion, innplantation or feeding will produce a greater incidence and an earlier appearance of mammary cancer than in the untreated mice. That, again, sounds formidable, but let us listen to the whole evidence. The amounts of estrogen needed to produce cancer or the premature ap- pearance of cancer in the e specially-bred mice is, weight for weight, about a thousand times the maximum given to a hunnan female, for therapeutic purposes, whereas smaller amounts will not suffice to produce cancer in the nlouse. But that is not the whole story yet. Cancer does not start overnight. One has to use estrogen for a period of time which is about one-third or more of the life span of the mouse. So, if you would treat a woman with one thousand times the therapeutic dose of estrogen over one-third of her life span or more, and she would belong to a cancer race, she might get a cancer of the breast. Let us not talk now about the cosmetic application of minimal physio- logically ineffective doses of estrogen, but consider therapeutic doses of estrogen used by gynecologists or endocrinologists for the past three dec- ades.

ESTROGENS 119 The last statistics I have seen on this subject were by two gynecologists, both eminent in their field their joint experience related to ten thousand treatment years in women in the course of these ten thousand treatment years in women given estrogen, the incidence of cancer of the breast or the womb was slightly less than in ten thousand other women of the same age and race but not treated with estrogen. The difference was statistically not significant. Let us say there was no difference. Certainly there was no more cancer in the women who were treated with estrogen than in those who were not. Thus, the wide spread cancerophobia of estrogen is utterly unwarranted and not based on fact it is still fostered by people who have the least experience with the use of estrogen. Those of us who are using estrogen daily on a large number of women do not fear cancer. Cancer. does not occur in the course of the use of estrogen more often than in people who do not receive any estrogen at all. This is the main message I wanted to convey to you. And, I would like to close with the hope that you have heard evidence that estrogen in cosmetics does something to the skin, and heard that the use of estrogen in cosmetics properly limited in quantity is harmless.