Tobacco Documents Online

- 10 - the same sort by Harold Dorn of the National Institutes of Health (8) upon veterans who have Government insurance. This is a captive population and if the study can be }ept up long enough something valuable is sure to be learned, particularly if a few more questions can be asked the veterans. And we must not omit the long continued studies of Dr. Lombard in this State (19). There is one point of difference in Dr. Lombard's results from those of others. They plot death against rate of smoking as of a particu- lar time such as the time the study started; he plots against total life- time packs of cigarettes smoked. He then finds that there is little or no increase of lung cancer deaths until something like 9000 packs have been smoked. This indicates that there is a threshold, a substantial threshold so that one cou7ld smoke half a pack a day for 50 years before he reached it. There have been those who have maintained that there is no threshold, which seems to me unbiological. I shall use Dorn's figures (8) to give you some idea of the sort of results that are found. The general death rate of smokers of all kinds from all causes is about 22% greater than that of nonsmokers, meaning there- by those who never smoked. You may be surprised that there are veterans who never smoked, but nearly one fifth of the total experience of these veterans was in the never smoked class. The pipe and cigar smokers are up less than 10`/6and the figure is not too well established because the total experience is small. The regular cigarette smoker is up 58%. So much for the general death rate. When it comes to lung cancer the picture is very bad. Compared with those who never smoked, those who have used tobacco have six times as much lung cancer and the regular smoker of cigarettes alone has nine and a third times as much. It is only fair to point out that the total number of lung cancer deaths among nonsmokers was only 17 so that the ratio must have

a very large sampling error and could not be consid'ered as well established were there not other studies which give comparably large ratios. One of the interesting phenomena is that those who smoke cigarettes and something else have lower rates than those who smoke cigarettes alone. I have been told that this is so even for those who smoke as many cigarettes and some- thing else in addition'. Tb some this would seem a bit of an enigma and I cannot say how well established it is. I doubt if any explanation offered for it is we11 establiished. There are so few deaths from lung,cancer among cigar and pipe smokers that the ratio, though' above uni;ty, is not well established. This discussion could be pushed much further but it is not very interesting listening,to figures. So here is the great Enigma. Why does the mild little cigarette show up so badly when the big strong cigar and the stinking old pipe get off practically scot-free? Why is "up to 2 a pack" a day more harmful than 5 to 8'cigars or more than 20 pipes a day? (8), In the past decade I have read hundreds of pages of the literature (I somehow hate to call it science and I would not give the impression that it is elegant as literature) on the resolution of this enigma, and while there are suggestions of this or that for a possible answer, I do not find any decent proof of any. You might be interested to hear of some of the suggestions. Fiirst there is the paper. If you will disembowel a couple of cigarettes and burn the paper and the tobacco separately for comparison you will probably find ~I the burning paper the more acrid. There is very little paper in a ciga- Cf~ ® rette and probably most of its fomes goes off in the side-stream rather than ~ into the smoker's mouth'. Most chemists who have studied the matter think O there is not enough carcinogenic materi.al in the paper to do any damage. ~

- 12 - Then there is the tobacco itself. When burned' its smoke is a very complex mixture of chemicals, acid, alkaline and neutral, very labile and varying with the temperature of burning. There are undoubtedly in the mixture traces of a number of substances which would be carcinogenic if applied in suffi- cient concentration; but I recently heard~a very distinguished biochemist say that he had spent 5 years of his life and a good deal of somebody's money trying to find enough of any or all carcinogens in cigarette smoke to be carcinogenic to the lung in the concentrations to which it is exposed'y and he was through, was going to quit and do something else. Then there is the inhaling. It is believed that cigarette smokers inhale and other smokers do not. Dolll and Hill decided'(2, 3, 6) 7) on;the basis of some statistical trials that inhaling did not matter. There is a French study (1) which shows that i;nhalers have a little more lung cancer than non-inhalers, but the ad- dition is no more for the very heavy smokers than for the very light ones, which seems rather queer. When the association between cigarette smoking and~lung cancer was first revealed both in England and in this country we all felt that a first class prima facie case had been made for the smoking of cigarettes being,the cause of most of the lung cancer deaths, and it is doubtless true that, until somebody finds something else on which the blame can be as easily laid, the temptation to lay it on the cigarette will be practically irresist- ible. This much was certain 5 years ago when I attend'ed'the Glenburnie con- ference called'by the American Cancer Society to consider the situation. N Since then more statistical findings of much the same sort have come out ~ without adding much to the evidence. In the intervening five years millions 0 of dollars have been spent altogether by the American Cancer Society, by M the National Cancer Institute, by the Tobacco Industry Research Committee, ~ .41

- 13 - by the various tobacco companies in their own laboratories and by similar organizations in Britain a.nd France trying to find out what it can be about the mild little cigarette which gives it this bad statistical picture. Thus far nobody has found out; there have been claims but so far as I have learned they have not stood.the test of time. I presume that if we knew that something specific in the cigarette caused the trouble the very good industrial chemists of the industry could take it out -- unless it were the nicotine -- and give the public a "safe" cigarette which would be en- tirely acceptable; I doubt if a dsnicotinized product would be satisfactory, for I believe we want the nicotine. Denatured wine) coffee and other prod- ucts do not seem to be popular. I do not know why we want the nicotine. Most of us have un- pleasant experiences from our first contacts with tobacco and on the Pavlovian theory of conditioning should tend to be conditioned against it. Perhaps it is only that we see that those habituated to it seem to get so much pleasure or comfort or some sort of satisfaction from its use. I remember talking about this matter many years ago with the great food chemist and generally learned scientist Carl Alsberg as we were passing the time smoking on a trip across the continent. Alsberg remarked that, so #'sx as he knew; the human race sometime somewhere had tried to use in its diet every plant like tobacco which contained some poisonous alkaloid like nicotine or morphine or caffeine. Whea I suggested that sometime somewhere the human group may have been short enough of rations to try anything that was edible; he said that that was not what he had in mind but that for some unknown reason the human animal needed one or another of these poisonous alkaloids in moderation. In an introductory paragraph to a brief note in 1938 on tobacco smoking and longevity; Raymond Pearl (22) estiroe,ted that

- 14 - 90% of the world's adult population used one or another of some such prod- ucts, including alcohol, and~said that the purely hedonistic elements in behavior, present in the lower animals as well as in man, have real importance. I mentioned earlier that Lombard and Doering found'that native stock had less cancer than the foreign~born. The Registrar-General in Britain tabulates deaths by social class in some of his studies. Recently Herdan of the department of Public Health in the University of Bristol, England (15)1, has discussed lung cancer by social class on the basis of these figures of R.-G. (1958): Standardized Mortality Rates for ages 20-64 and Years 1949-53: Males Married Women Class I II III IV V I II III IV V Rate 81 82 107 91 118' 119 95 102 98 96 The correlation coefficient for males is 0.81 and for females - 0.69. I really cannot compare these figures withiours because we have not the same classification and I do not know how meaningful they are anyhow, for to cor- relate on the basis of 5 classes is not very satisfactory. I do it not to criticize Herdan (who does not do it) but to point out that if we take these correlations seriously, they mean that in England 66% of the variance of the death rate for men and 48y6 for women is accounted for by their social class, leaving only 34% and 52% respectively to be explained by the amount of smok- ing, except as that is correlated with social class and thus includ'ed~with it~ automatically in the figures. [jt In my concluding remarks I wishistrongly to emphasize this point. ~ The problemlof the explanation of the association of lung cancer andiciga- rette smoking, or of any two ve.riables, in a mulitivariate situation cannot

be solved'by considering just two of the variables of which one is assigned'the role of effect and the other the role of cause of that supposed effect. It is rare that the real cause of any cancer in anybody is known. Various types of cancer in a population are associated in~various degrees with a variety of variables, none of which may be a real cause any more than bad'air was the real cause of malaria or typhoid (or other diseases) which the Century Dictionary had mixed together in the definition I quoted at the start. Some of the variables known to be associated with the lung cancer d'eath rate in Britain are: social class, urbanizationy atmospheric pollution, sex, age, and smoking. It is probable that individual genetic constitution is also important, but very hard to specify in a species so heterozygous as man. In Britain there seems to be a very high~correllation between lung cancer, urban. izatiomand atmospheric pollution; in this country the impression seems to prevail that these correlations are lower; for neither country have I seen any satisfactory multivariate analysis of the problem. Although the statistical situation is far from satisfactory as an analysis of possible causation, and the chemical situation is enigmatical in its inability to find in the cigarette anything in sufficient quantity to~ cause lung cancer, the statistical association of lung cancer and cigarette smoking continues to keep alive the hypothesis that smoking cigarettes is somehow responsible for a good many of the cases of lung cancer, and there- fore leads to speculation that if nobody smoked cigarettes there possibly would be less lung cancer. Certainly, however, if nobody smoked cigarettes N there would be amarked decrease in one of those hed'onistic elements in our F~.l ~ living which Pearl seemed to feel so important humanly as often to overbear Q ~ both reason and'physiological]1y inhibiting influences. ~ ~ d

- 16 - If as the great British geneticist R'. A. Fisher* and the great American geneticist C. C. Little seem to feel, the individual constitu- tion is primarily the cause of an individual's susceptibility to lung can- cer, the whole matter must come d'own to the balancing by the individual of his willingness to take whatever risk there may be with the pleasure he has in smoking cigarettes. Sometime we may know more about the individ!ual, the cigarette and lung cancer in their mutual relationships. *Sir Ronald Fisher has recently published from the house of Oliver and Boyd a brochure of about 50 pages in which he has collected some of his essays under the title "Smoking: The Cancer Controversy: Some Attempts to Assess the Evidence." BIBLIOGRAPHY 1. DENOIX, P. F., SCHWARTZ, D. & ANGUERA, G., Bulletin de l'Association Francaise pour l'Etude du Cancer 45/1:1-37, Jan.-March 1958 2. DOLL, R. & HILL, A. B., British Medical Journal, Sept. 30, 1950:739-748 3. Ib id~. , De c. 13, 1952':1!271-1286 4. IbU., June 26, 1954:1451-14~55 5. Ibid., Nov. 10, 1956:1071-1081 6. DOLL, R'., Acta Unio~Intl. Contra Cancrum, 15/2:417-423, 1959 7. Ibid., 15/6:1283,1296, 1959 ~ O 8. DORN!, H. F'., Public Health Reports, 74/7:581-593, July 1959 0 9. GILLIAM, A. G., Military Medicine, 116/3!:163-174, March 1955 a) 10. GILLIAM, A. G., J. Nat. Cancer Institute, 15/5:1307-1312, April 1955 ~ 11. GILLIAM, A. G., Cancer, 8/6:1130-1136, Nov.-Dec. 1955 ~ 12. GREENWOOD, M., J. Royal Statistical Soc., Series A, Part III:230-234, ]1948 13'. HANASOND; E. C. & HORN, D., J. Am. Med. Assn., Aug. 7, 1954:1316-1328' 14. Ibid., March 8, 1958:1159-1172 and March 15, 1958:1294-1308' 15. HERDAN, G., Brit. J. of Cancer, 12/6:492-506, Dec. 1958 16. LEW, E. A., J. Intl. College of Surgeons, 24/1:12-27, July 1955

- 17 - 17. LO W H. L. & DOERING, C. R., Proc. Nat. Academy of Sciences, 13/10:728- 735, Oct. 1927 18. LONISARD, H. L. & DOERING, C. R., J. Am. Med. Assn., April 26, 1928: 481-487 19. LOMBARD, H. L. & SNEGIREFF, L. S., Cancer, 12/2:406-413, March-April 1959 20. MYERSON, M. C., California Medicine, 82/2:111-113, Feb. 1955 21. MYERSON, M. C., Annals of Oto. Rhino. Lar., 64/2:412-417, June 1955 22. PEARL, R., Science, March 4, 1938:216-217 23. RIGDON, R. H. & KIRCHOFF, H., Texas Rep. Biol. & Med., 10/1:76-91, Spring 1952 24. Ibid., 11f4:715-727, Winter, 1953 25. RIGDON, R. H., Southern Med. J., 50/4:524-532, April 1957 26. ROSENBLATT, M. B. & LISA, J. R., "Cancer of the Lung," Oxford U. Press, 1956 27. ROSENBLATT, M. B., J. Kentucky State Med. Assn., 56/2:131-136, Feb. 1958 28. SCHERESCHEFISKY, J. W., U.S. Public Health~Bulletin #155: "The Course of Cancer Mortality in the Ten Original Registration States for the 21- year Period 1900-1920 (with Statistical Appendix by Edwin B. Wilson.)" 29. SCHERESCHEWSKY, J. W., J. Am. Med. Assn., Oct. 17, 1925:1175-1180 30. WILKIl3S, E'. E. Jr. & SWEET, R. H., New Eng. J. of Med., Feb. 21, 1957: 346-351