committee did not discuss the process whereby risk assessment might achieve maximum relevance, how it might be tailored in scientific depth to match the decision-making context, or how various stakeholders might influence the question of specifically what risk assessment should focus on in specific decision contexts. Those were not central issues for the Red Book committee. They clearly are issues for today in the evolution of risk assessment.


To ensure that risk assessments are maximally useful for risk-management decisions, the questions that risk assessments need to address must be raised before risk assessment is conducted and may need to be different from the questions that risk assessors have traditionally been tasked with answering. The more complex and multifaceted the problem to be dealt with, the more important the need to operate in that fashion. As noted in the previous section, the Red Book framework was not oriented to identifying the optimal process for complex decision-making but rather to ensuring the conceptual separation of risk assessment and risk management. A framework for risk-based decision-making (Figure 8-1, “the framework”) is proposed here to provide the guidance that was missing from the Red Book. Its principal purpose, in the context of the present report, is to ensure that risk assessment is maximally useful for decision-making; as noted, this would fulfill the second of our two criteria for improving risk assessment. The framework is also intended to ensure that the methodologic changes recommended in Chapters 4-7 are put to the best use, given the repeated emphasis on analytic efforts that are appropriate to decision-making in scope and content. We offer some background on the framework in this section and then describe it more fully in the next section.

Perhaps the easiest way to explain the basic difference between the framework and the traditional assessment-management relationship is to look first at the beginnings and ends of each process. We start with an assumption that in either model no analysis would be done and no decision would be needed unless some “signal” of potential harm had come to EPA’s attention. The signal can arrive in many forms, but it would generally involve a set of environmental conditions that appear to pose a threat to human or environmental health. The traditional process receives that signal and begins immediately with the question, What are the probability and consequence of one or more adverse health (or ecologic) effects posed by the signal? The framework (in Figure 8-1), in contrast, receives the signal and asks, What options are there to reduce the hazards or exposures that have been identified, and how can risk assessments be used to evaluate the merits of the various options?

Beginning the inquiry with the latter type of question immediately focuses attention on the options for dealing with a potential problem—the risk-management options. The options are often thought of as possible interventions—actions designed both to provide adequate public-health and environmental protection and to satisfy the criterion of well-supported decision-making. We note that, in most cases, “no intervention required” is one of the options to be considered explicitly.

In the framework, the questions to be posed for risk assessment arise from early consideration of the types of assessments needed to judge the relative merits of the options considered. By examining both the options and the types of assessments available, one may expand the scope of the options considered to embrace other possible interventions. Risk management involves choosing among the options after the appropriate assessments have been undertaken and evaluated. Assessments of relevant risk-management factors other than risk—such as costs, technical feasibility, and other possible benefits—also require early planning.

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