The committee arrived at its position after extensive discussion and deliberate consideration of many factors, including primarily the great variations in risk assessments among and within federal agencies and the fact that the expertise in risk assessment in the federal government resides, for the most part, in the agencies or with those with whom the agencies work.
Risk assessment is not a monolithic process or a single method. All risk assessments share some common principles, but their application varies widely among domains. Different technical issues arise in assessing the probability of exposure to a given dose of a chemical, of a malfunction of a nuclear power plant or air-traffic control system, or of the collapse of an ecosystem or a dam. And different technical issues arise in assessing the consequences of an accidental release from a nuclear power facility and an accidental release of a pesticide.
Risk assessment is not a field peopled with all-purpose experts. There are some with expertise in toxicology, decision analysis, dose-response assessment, ecologic risk assessment, engineering, and exposure assessment. In industry, some firms that specialize in one domain would not take on work in another. Federal agencies have staff familiar with the issues that are relevant to their missions; agencies without resident expertise have contractors with whom they have been working or associations to which they can turn.
One size does not fit all, nor can one set of technical guidance make sense for the heterogeneous risk assessments undertaken by federal agencies. Although the bulletin reflects that diversity and attempts to meet it with frequent references to “where appropriate” or “where feasible,” the committee concludes that this approach is not workable for the agencies. As stated above, the committee strongly recommends that technical guidance be produced by the agencies and that agencies dealing with the same or similar hazards work together to produce common guidance to ensure an appropriately consistent approach.
As noted above, the committee agrees that there is room for improvement in risk assessment practices in the federal government and that additional guidance would help “to enhance the technical quality and objectivity of risk assessments prepared by federal agencies.” However, the bulletin conveys the impression that risk assessments can and should achieve total objectivity. Although any scientific work should be free of bias, scientifically accurate, and based on reliable evidence, risk assessments cannot be wholly objective, because some important assumptions and judgments are based on policy or statutes. The committee strongly