Science and politics: the possible regulation of cancer promoters.

To address the problems associated with the regulation of tumor promoters, one must recognize that a regulatory agency's actions in the formulation of policy redound from a matrix of political, social and scientific pressures; each affecting the other, and all influencing the final policy outcome. Scientific understanding of the mechanism(s) of tumor promotion plays a determinant role in such interaction, for the selection of particular biological tests as surrogates for human response to chemical exposure provides the radical upon which such interaction occurs, industry responding to the legal, regulatory instrument that relies in turn on scientific confidence in required tests. These parties operate within the penumbra cast by political expedients, environmental action groups, and special interest lobbies whose concerns involve the cost of testing, the availability of resources, the consideration of particular chemicals of economic or symbolic value, and other such aspects of regulatory policy or its consequence. In examining the complex development of policy for future regulation of tumor promoters, we must attend first to the legal instrument framing such regulations, assessing probable impact on these various scientific, economic, social and political factors. Potential regulation of most tumor promoters would fall within the regulatory ambit of the U.S. Environmental Protection Agency, specifically the Toxic Substances Control Act of 1976 (TSCA). As with other regulatory acts, the making of public policy, in this case concerning the manufacture and use of chemicals, derives from two major concerns: the attempt to achieve technical analyses of risks and benefits as one base for regulation, and a gener-