worthwhile and needed research activities that are already under way, the potential difficulty of changing research directions for some of the federal career research scientists in EPA's intramural laboratories, the technical information needs of EPA's regulatory offices, and the infrastructure costs of establishing and maintaining the research centers requested by Congress.
Over time, the research investment portfolio summarized in Table 5.1 would go a long way toward meeting the needs of decisionmakers, providing some answers for the next phase of decisionmaking and others later. The results of this recommended research would fill the key gaps in the committee's framework for establishing links between particulate-matter sources and health risks. Some questions (e.g., the long-term health effects of air pollution on public health) will require sustained investigation.
The research costs estimated by this committee can be viewed as investments in the scientific foundation upon which all particulate-matter regulatory activities of EPA, state and local governments, and the private sector—planning, implementation, monitoring, compliance, and enforcement—will be built. A solid scientific foundation can help ensure that the other investments yield a sound return. An inadequate foundation will lead to continued uncertainty, contentious debates, and potentially unwise investments that fail to minimize the risks of particulate matter to public health.
The committee realizes that questions undoubtedly will remain about some of the key areas of uncertainty, even after new scientific results have been obtained. Therefore, future judgments will need to be made on the adequacy of new scientific information to address those uncertainties and on the appropriateness of moving from one phase of the committee's recommended research strategy to another. Nevertheless, a coherent and effective particulate-matter research program will require a strongly iterative process that assimilates and uses the results of the multidisciplinary research recommended in this report.