Tobacco Documents Online

E2 I0. scale of production of which would not otherwise have justified the expense of irriga.tion. A similar "spin off" effect has occurred with tractors and cultivation equipment in West Africa. In the State of Western Nigeria, the tobacco companies' sponsored tractor schemes are used both by tobacco and by non tobacco farmers and through their example has led to the establishment of similar schemes by Government and by other operators. In the more advanced agricultural economies of Venezuela, Argentina and Brazil, the tobacco companies have established soil analytical programmes, often conducted in their own laboratories. This enables advice to be given to farmers on lime and fertilizer requirements for the best crop yields. Where tobacco is grown in rotation with other crops, the soil analysis can be used to provide a fertilizer programme for the alternate crop. The rapid spread of intensive cropping in the Third world has brought with it problems of soil erosion and loss of natural soil condition and also weeds, pests and disease. Particularly in the tropics, this loss of organic matter and soil structure are accen- tuated where primitive tools and implements are used. Subsoiling and deeper ploughing have been advised and are now common practice in Central America and parts of East and West Africa as a means of breaking up the hard pan which had developed. Water permeabi- lity has been improved and the potential root zone of the soil increased. In Northern Nigeria, the tobacco companies are evaluating alterna- tive cultivation techniques which result in reduced wind erosion at the beginning of the wet season. On land which is undulating or hilly, as in Kenya, farmers are advised and encouraged to construct contours and plant on the contour. In Brazil, 95 per cent of the tobacco crop is planted by farmers who observe the principles and practive of soil conservation. Traditionally, farmers have removed or burned crop residues. However, the use of tractors and modern equipment had enabled them to plough in crop residues to maintain the level of organic matter -in the soil. In one country, Nicaragua, many farmers are indeed growing a green manure crop specifically for this purpose. llth May 1979

ICOSI BACKGROUND BRIEFING PAPER F1 CLAIM The tobacco companies encourage farmers in Third World countries to use wood for the flue-curing of tobacco thus depriving the poor man of his national fuel resources. RESPONSE The flue-curing of tobacco requires artificial heat, though other methods of curing do not. In Canada, the United States, the Caribbean, Central America, India and Indonesia, oil or coal or sometimes natural gas is used for flue-curing. The ideal unit for the production of flue-cured tobacco is however the family farm, and in some parts of the Third world the use of wood as fuel for flue-curing has had obvious advantages. Wood was available; it was cheap; its use demanded a lower level of techno- logy and did not involve the outlay of foreign exchange. In the earlier stages of tobacco production, wood was available from land clearance in many parts of Africa, from other agricultural activi- ties such as rubber plantations in Malaysia, from Government forest reserves in Sri Lanka, or from natural forests as in Brazil. Unfortunately, although Governments in these countries have generally encouraged the development of tobacco as a cash crop within their agricultural economy, with a few notable exceptions (such as Pakistan, where Government-initiated wood fuel plantations now produce 30.5 million cubic feet of fuel a year) their forestry Departments have been slow to see the need for reafforestation programmes. Whenever natural resources are used for any purpose, it is impor- tant to conserve them. For wood, reafforestation is a necessiry programme. Therefore, the tobacco companies have taken the initia- tive. It has not been possible for them to become directly involved in plantation. They have however encouraged farmers to plant trees, either on a co-operative basis or individually. Wood fuel colopera- tires jointly owned and managed by the farmers were very successful in Uganda but the agricultural systems in other countries have not allowed them to be set up elsewhere. Tree planting by individual farmers also encounters difficulties, sometimes because of the land tenure system, sometimes because of the limited size of the farmer's holding, and sometimes because he cannot envisage the future fuel requirement. Nevertheless, in a number of countries the tobacco companies have successfully encouraged farmers to plant trees, usually exotic fast-growing species, on any free land and using seedlings provided free by the company. As a result of 03678384

F2 co-operation between the tobacco companies and the farmers, 115 million trees have been planted in Brazil since 1977 alone. Other examples are in Kenya, where 3 million seedlings have been issued during the past three years, and in Sri Lanka where 40 seedlings are issued free to each farmer every year. Ii has also been possible to reduce fuel requirements by recommen- ding improved curing techniques and by improving the efficiency of wood furnaces. Technical improvements developed to meet problems in one country have been transferred to other countries where similar problems occur. '" Several tobacco companies are conducting research into the use of waste products as fuel. For example, the conversion into briquet- tes of waste material from coir, rice husk and sawdust is currently under investigation in Sri Lanka and the results could prove useful in other countries including Brazil. Trials are being oonducted in Kenya of solar energy as a supplementary source of heat for flue- curing. llth May 1979

ICOSI BACKGROUND BRIEFING PAPER SMOKING AND HEALTH -- A PERSPECTIVE For centuries, millions of people throughout the world have enjoyed smoking tobacco in various forms. The explorer, Christopher Columbus, encountered natives in the West Indies smoking tobacco when he discovered the New World in 1492. Tobacco was introduced to Western Europe in the sixteenth century, and it was not long before the custom of smoking began to spread. Nor was it long before smoking began to be attacked. G1 Today, tobacco use continues to be opposed primarily on the grounds that it is a health hazard--a claimed cause of lung cancer, cardiovascular disease and other disorders. The claims that are made about imoking and health rely mainly on reported statistical associations, but it is a scientific principle that such associations cannot establish causal relationships. Even the 1964 U.S. Terry Report noted that "statistical methods cannot establish proof of a causal relationship in an association." What statistical associations can do, however, is point to the need for further clinical and laboratory research to determine the precise relationships.l Moreover, considerable scientific data are inconsisten~ with the smoking-disease hypothesis. Indeed, there is ample scientific evidence showing that the smoking and health question is unresolved. 0~783~6

G2 This is illustrated by an examination of the accusation that tobacco use is a major cause of premature death. Some of the major statistical studies of select populations contain findings inconsistent with this accusation. In separate studies of Canadian and U.S. veterans, it was found that veterans with longer smoking histories did not necessarily experience higher mortality rates. One showed that persons who had smoked for 25-34 years had lower mortality rates than persons who had smoked for 15-24 years, and the other that smokers of 15-29 years had lower rates than persons who smoked for less than 15 years.2 Also of interest is the 10-year study of residents of towns in Denmark and England.3 In the Danish town, researchers found that nonsmokers had a higher death rate than those who smoked cigarettes, pipes and cigarettes, and other forms of tobacco. In the English town, they found that the "heavier" smokers had lower death rates than the "lighter" smokers. The reported statistical associations between smoking and higher mortality rates may be more consistent with a genetic hypothesis than a causal one, according to certain highly respected scientists. Studies of identical human twins provide support for this theory. Because identical twins have the same genetic makeup, they are excellent subjects for the study of extrinsic factors which may affect mortality. These studies have indicated~ that in identical twin pairs who have different smoking habits, no excess mortality has been observed in the twins who smoked more heavily.4 ~

In view of such scientific uncertainties, it is unfortu- nate that discussions of smoking and health questions have frequently become strident. Rationality is often replaced by emotionalism, a situation commented on recently by Dr. Gary Huber of Harvard University: "When it comes to tobacco, opinions are given often with such emotionalism that there is very little discussion, much less scientific objectivity."5 However, scientific objectivity is needed in considering complex questions of disease causation. Despite the many claims made about smoking and health, a legitimate and continuing scientific controversy surrounds the subject. The smoking and health question is unresolved and answers will be found cnly through unbiased scientific inquiry. May 1979

G4 References Berkson, J., "Smoking and Cancer of the Lung," Mayo Clin Proc 35: 367-385, 1960. Berkson, J.,. "Mortality and Marital Status: Reflections on the Derivation of Etiology from Statistics," Amer J Pub Hlth 52(8) : 1318-1329, 1962. Berkson, J., "Smoking and Lung Cancer," Med Proc i0: 327-336, 1964. Burch, P. R. J., "Problems in the Interpretation of Cancer Statistics with Special Reference to Lung Cancer," J Soc Occup Med 25(1): 2-10, 1975. Fisher, R. A., "Dangers of Cigarette-Smoking," Brit Med J 2(5039): 297-298, 1957. Fisher, .R.A., "Cigarettes, Cancer and Statistics," Centennial Rev Arts Sci 2: 151-166, 1958. Fisher, R. A., "Lung Cancer and Cigarettes?" Nature 182(4628): 108, 1958. Fisher, R. A., Smoking: The Cancer Controversy.' London: oliver & Boyd, 1959, pp. 7-47. Rigdon, R. H., "Cigarette Smoking and Lung Cancer: A Consideration of This Relationship," South Med J 62(2): 232-235, 1969. Rigdon, R. H., Statement presented at Hearings before the Committee on Interstate and Foreign Commerce, House of Representatives, April 15 - May I, 1969. Serial No. 91-12, pp. 1018-1025. Schoolman, H. M., et al., "Statistics in Medical Research: Principles Versus Practices," J Lab Clin Med 71(3): 357-367, 1968. Seltzer, C. C., "An Evaluation of the Effect of Smoking on Coronary Heart Disease," JAMA 203(3): 193-200, 196S. Yerushalmy, J., "On Inferring Causality from Observed Associations," Controversy in Internal Medicine, F. J. Ingelfinger, et al. (eds.).--Philadel~hia: W. B. Saunders Co., pp. 659-668, 1966.

G5 U. S. Public Health Service. Smoking and Health, Report of the Advisory Committee to the Surgeon General of the Public Health Service. Washington, U. S. Department of Health, Education, and Welfare, Public Health Service Publication No. 1103, p. 20, 1964. 2. Doll, R. and A. B. Hill, Mortality Study in British Doctors, and Best, E. W. Ro, et al., Mortality of Canadian War Pensioners, as Reported in: U. S. Public Health Service. Smoking and Health, Report of the Advisory Committee to the Surgeon of the Public Health Service. Washington, U. S° Department of Health, Education, and Welfare, Public Health Service Publication No. 1103, p. 93, 1964. 3. Cole, T. J., et al., "Bronchitis, Smoking and Obesity in an English and a Danish Town: Male Deaths After a 10-Year Follow-up," Bull Physio Path Resp 10(5): 657- 679, 1974. 4. Cederlof, R., et al., "Morbidity Among Monozygotic Twins," Arch Environ Health 10(2): 346-350, 1965. Cederlof, R., et al., "Respiratory Symptoms and 'Angina Pectoris' in Twins with Reference to Smoking Habits. An Epidemiological Study with Mailed Questionnaire," Arch Environ Health 13(6): 726-737, 1966. Cederlof, R., et al., "Hereditary Factors and 'Angina Pectoris,'" Arch Environ Health 14(3) : 397-400, 1967. Cederlof, R., et al., "Hereditary Factors, 'Spontaneous Cough' and 'Smoker's Cough,'" Arch Environ Health 14(3): 401-406, March, 1967. Cederlof, R. and L. Friberg, "Tobacco Smoking and Health: Results of Epidemiologic Studies in Twins," Lakartidningen 65(27): 2727-2734, July 3, 1968. Cederlof, R., et al., "Cardiovascular and Respiratory Symptoms in Relation to Tobacco Smoking: A Study on American Twins," Arch Environ Health 18(6): 934-940, 1969. Cederlof, R., Statement presented at Hearings Before the Committee of Interstate and Foreign Commerce, House of Representatives, April 15 - May i, 1969. Serial No. 91-11, pp. 873-882.

G6 De Faire, U., et al., '"Concordance with Respect to Mortality in Ischaemic Heart Disease and Cerebrovascular Disease, A Study on the Swedish Twin Registry," CVD Epidemiol Newsl 18(1): 21, 1975. Friberg, L., et al., "Smoking Habits of Monozygotic and Dizygotic Twins," Br Med J 1(5129): 1090-1092, 1959. Friberg, L., et al., "Mortality in Smoking Discordant Monozygotic and Dizygotic Twins," Arch Environ Health 21(4): 508-512, 1970. Friberg, L., et al., "Mortality in Twins in Relation to Smoking Habits and Alcohol Problems," Arch Environ Health 27(5): 294-304, 1973. Huber, Gary, "State of the Art on Tobacco and Health," Paper presented at the American Thoracic Society Annual Meeting, May 15, 1978.

ICOSI BACKGROUND BRIEFING PAPER HI Smoking and Lung Cancer The accusation that smoking causes lung cancer is well publicized. What is perhaps not so well publicized is the considerable amount of scientific evidence that questions this causal hypothesis. The claim that smoking causes lung cancer is based mainly on studies in which smoking was reported to be statistically associated with lung cancer mortality. But this reasoning ignores the important question of whether or not such associations have causal significance. Scientists generally agree that statistical associations do not establish causal relationships. Dr. Joseph Berkson, the distinguished medical statistician now retired from the famed Mayo Clinic in the United States, has stated that "Cancer is a biologic, not a statistical, problem" and that "if biologists permit statisticians to become the arbiters of biologic questions, scientific disaster is inevitable.''I However, such associations do point to the need for further ..~ 2 clinical and laboratory investigations. A number of laboratory and clinical findings have raised serious questions about the alleged causal relationship between smoking and lung cancer. These include the fact