Application of Conservative Assumptions and Precaution

Other experts have expressed concern that while the use of conservative assumptions may be appropriate initially when uncertainty is large, it is problematic if the initial use of such assumptions prevents revision of risk estimates when new data become available for political reasons One implication of the inherent conservatism in risk assessment is that the inevitable consequence of most scientific advances related to the assessment of risk for individual chemicals is to lower the calculated risk. The worst thing that we can do is to set up a situation so that we cannot use this increased scientific information because of the political aspects of changing numbers (Goldstein 1989). Still others argue that risk assessments are not conservative enough and that they underestimate risks because, for example, they fail to fully account for susceptible subpopulations and the synergistic effects of some toxic exposures (Finkel 1996 Latin 1988). 

The court added that [w]hile the EPA may err on the side of overprotection, it may not engage in sheer guesswork.  

Science policy issues and controversies underlie almost every aspect of cancer risk assessment. These policy issues are primarily a function of the scientific uncertainties inherent in risk assessment. As new scientific methods and data begin to fill in some of the data gaps and uncertainties in risk assessment, the role of policy will gradually recede, although there is no prospect of policy issues being mooted entirely in the foreseeable future. Moreover, the extent to which we substitute novel scientific data and models for preexisting policy inferences is itself an ongoing policy debate, as is the appropriate role of precaution and conservatism in risk assessment. 

AFL-CIO (1992). American Federation of Labor and Congress of Industrial Organizations v. Occupational Safety and Health Administration, U.S. Department of Labor, 965 F.2d 962 (C.A. 11). 

Albert, R. E. (1994). Carcinogen risk assessment in the U.S. Environmental Protection Agency. Crit Rev Toxicol 24, 75-85. 

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