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EDITORIAL
Chemical carcinogenesis The management of carcinogenic risk from chemical exposure is an increasing focus of public policy in the United States. A recent ES&T feature (May 1987, p. 415) summarized 132 federal regulatory decisions for management of exposure to chemical carcinogens. More than two-thirds were promulgated during the past three years. Although the legislative net has been firmly set, the regulatory harvest has just begun. We are not alone in this regard, but the level of intensity in the United States far exceeds that of other nations around the world. Why single out carcinogen risk management? Management decisions for carcinogens often result in 2 to 5 orders of magnitude more stringent controls than those required for other toxicity end points. Meeting those control levels for a growing number of chemicals showing carcinogenic activity will be a strain on our technological and financial resources. The question might be asked as to whether the health benefits will be worth the costs in terms of reduced standard of living, altered lifestyles, and new risks resulting from each regulatory action. Improvements in cancer mortality from control of chemical exposures will probably never be measurable, because lifestyle factors (e.g., diet, smoking, alcohol consumption) dominate cancer incidence. But standard-of-living changes and costs associated with control of exposures, now largely hidden, are likely to become more visible in the years ahead. Risk assessment-the analysis of scientific data to characterize the magnitude of risk to humans from exposure to carcinogens-will provide a basis for establishing the degree of control necessary to reduce risk. Risk assessment is in its infancy, but we hope that it will not stay there. A major cancer risk management program, based on poorly understood science, has great potential for economic disaster at a time when the competitiveness of the United States is severely challenged. ES&T will feaNre a series of articles during the next five months addressing several aspects of carcinogen risk assessment intended to stimulate advancement in the science. Several things need to happen to bring about advancement, and they need to happen soon! M)1%936W87/09210611$01.~/0 0 1987American Chemical Sociew
First, a concerted effort must be made to improve the science of carcinogen risk assessment. Risk assessment should be identified as a national priority. Laboratories should be designated to conduct critical investigations, and continuous monitoring is required to ensure progress toward the goal of estimating human risk more accurately from experimental data. A national focal point is needed, perhaps with a panel of scientific experts to spearhead the effort. Second, data on more substances relating to mechanism of carcinogenic action, metabolism, pharmacokinetics, and exposure should be generated and published. Clearly, it is difficult to go beyond upper-bound estimates of risk without the convincing data to support more accurate estimates of human risk. Third, the advancing science must be utilized to its fullest. Too often conservative, simplistic assumptions are used in risk assessments despite the existence of data that could improve the estimate of risk, and the risk manager has only upper-bound estimates on which to base decisions. Finally, the communication of risk-related information to the general public needs to be improved. Rarely is it required that results from an infant science be communicated beyond the scientists themselves to the general public, particularly on such an emotional subject. But the public should have a voice in where we strike a balance, and it is essential that their decision be based on all that science has to offer.
Raberl J. M d e n a a r is project director in the Dow Health and Environmental Research Department. He is a former director of Dow S Environmental Sciences Research Labomtory and former chairman of the American Industrial Health Council's Scientific Committee. He also advises EPA on test method developmentfor the Organiwtion for Economic Cooperation and Development. Environ. Sci. Technol.,\lol. 21. NO. 7. 1987 611
