Document LpG1OwL1Bk1w37npEMZgxQokq

V. . * 76, R. N. Sawyer. Environ, firs. 13, 146 (1977). > 77. TLV's, Threshold Limit Vuhu-s for Chemical * Substances In Workroom Air Adopted by : fjACGlHfor I960 (American Conference of Gov* ' eramental Industrial Hygienists, Cincinnati. Ohio, 1980). - 78. Asbestos--General Information (Asbestos In* formation Association of North America. Wash* "''ington. D.C.. 1075). 79. M. Villeco. Archil. Forum 133. 30 (1970). 80. ' A. 14. Rohl and R. N. Sawyer, paper presented at the International Symposium on Indoor Air Pollution, Health, and Energy Conservation, Amherst. Mass.. 13 to 16 October 1981. 81. R. L. Murphy. S. W. Levine, F. J. A) Bazzaz.J. J. Lynch, w. A. Burgess. Am. Rev. Respir. Dis. 104,576(1971). 82. Occupational Safety and Health Administration, "Standard for exposure to asbestos dust," Fed. Regist.37, 11318 (1972). , 8). "Revised recommended asbestos standard." ' U.S. Dept. Health Educ. Welfare Pub!. (NIOSH) 77-169 0977), 84. R. N. Sawyer and C. M. Spooner. U S. Environ. Frol. Agency Publ. EPA-450/2-7a-OI4 (1978). 83. U.S. Environmental protection Agency, "Amendments to asbestos standard," Fed. Re- ist. 43, 26372 (1978). tarfcthop on Indoor Air Quality Research Needs, Interagency Research Group on Indoor Air Quality, Leesburg. Va., 3 to 5 December 1980. 87. "Position statement on indoor quality," J. Air PoUut. Control Assoc. 32. 348 0982). . /'^yy f^ 88. The American Society of Heating, Refrigera tion. and Air Conditioning Engineers, Inc., `Po sition statement on indoor sir quality," ap- Cved by the ASHRAE board ofdirectors on 1 j 1981. 89. J. L- Repace. Environ. Int. 8, 21 (1982). 90. K. Sexton and R. Repetto, Ibid., p. S. 91. This work wu supported in part by NIEHS grant ES-01108. EPR1 grant RP-1001, end EPA grants 68-02*3201 end 2974. We thank the mem bers of the staffand faculty at Harvard University who commented on earlier versions of this manuscript: M. J. Ellenbecker, J. S. Evans. M. W. First, R. Leu, D. W. Moeller. P. B. Ryan, S. R. Thomas, R. D. Treitman, and W. A. Turner. We are also grateful to A. Maskcll who typed the article and provided editorial comments. | 1 1 1 ,| : t / '* t Cost-Effective Priorities for Cancer Prevention Milton C. Weinstein Environmental factors are responsible pie, but current understanding leaves us for 80 to 90 percent of cancer deaths m. far short of being able to prevent most the United States (7,2). This conclusion, 'cancer in fact. The challenge of the comwhich once aroused considerable contra- ing decades will be to identify the specifversy, is now generally accepted, pro- ic agents that cause or prevent cancer vided that the '`environment" is broadly and, after identifying them, to develop Summary. Faced with limited resources, the United States must set priorities for research to identify preventable causes of cancer. A quantitative approach to priority setting, based on principles of decision analysis and cost-effectiveness analysis, can offer guidance In this process. An illustrative application of such a model suggests that the National institutes of Health-supported clinical trial of dietary p-carotene offers a greater expected reduction in cancer mortality per research dollar than carcinogen bioassays of high-volume industrial chemicals such as p-dichlorobenzene. National research priorities should reflect the relative cost-effectiveness of such investments. defined to include not only industrial chemicals and pollution, but also diet, reproductive behavior, and other ele ments of life-style and culture, as well as such natural phenomena as infectious agents and nonionizing radiation. Doll and Peto have placed the contribution to U-S. cancer mortality of occupational and environmental exposures to industri al chemicals at less than 5 percent, in cluding 2 percent due to asbestos (2). . Growing hope during the 1970's that cancer could be controlled in large part by detecting and eliminating carcinogens has been tempered during the 1980'$ by the sober realization that preventing can cer will not be simple. Epidemiologic data firmly support the proposition that most cancers are preventable in princi- and implement interventions to alter hu man exposure to them. The problem of identifying carcino gens in the environment seems formida ble enough when attention is focused on the 70,000 or so industrial chemicals in production. The cost of testing this in ventory of chemicals, let alone the thou sands of new chemicals entering produc tion each year, would be huge. Even if financial cost were not a constraint, the limited supply of toxicologists and laboratories would constrain the volume of long-term bjoassays. Epidemiologic insights should, howev er, lead us to examine the priority-setting problem in a broader framework. If in dustrial chemicals other than asbestos account for 3 percent of cancer deaths. I JULY 1983 V ' the prospect of saving 12,000 lives each year (out of 400,000 cancer deaths) should encourage us to discover the key industrial agents and control exposure to them. But if 35 percent of cancer deaths are related to diet (2), efforts to discover dietary factors in cancer might deserve an even greater claim on resources. Toxicologic studies of industrial chem icals and epidemiologic studies of dietary agents are, in general, funded from dif ferent budgets, and might seem not to be in competition for the same limited re sources. For the society as a whole, however, it is imperative to ask how best to spend resources in the general domain of cancer prevention. Priorities need to be set among alternative research strate gies for detecting carcinogenic and anti- ^ carcinogenic agents, and such priority setting should encompass the full range of environmental factors (broadly de fined) in cancer prevention. This article illustrates a quantitative approach to priority setting, based on principles of cost-effectiveness and deci sion analysis. It also shows how the approach may be used to compare the cost-effectiveness of toxicologic studies of industrial chemicals and prospective trials of dietary constituents. The indus trial chemical examined is /7-dichloro benzene, the active ingredient in moth balls. The cost-effectiveness of a ran domized prospective trial of dietary Elcarotene, a close relative of vitamin A, is also assessed. This comparison and oth er considerations lead to policy implica tions regarding the optimal use of re sources in investigating the cancer-relat ed effects of environmental agents. Uncertainty is inherent in this kind of prospective analysis, and the attempt to quantitate this uncertainty may make some readers Uncomfortable. However, policy decisions must and will be made in the face of uncertainty, and analysis ' The author Is professor of Policy and Decision Sciences. Department of Biosutistics, Harvard School of Public Health. Boston, Massachusetts 02115. 17 URL 05407