In this chapter, the committee sets forth its recommendations. For convenience, it does so under four subject areas.
Estimates of dose from Nevada Test Site and global fallout
The committee recommends that changes be made in the draft report to clarify the assumptions, methods, and uncertainties related to dose estimation. Tables should be used to lay out the sources of uncertainty in the dosimetry and in the estimation of risk. The basis of a “credibility interval” of a factor of 3 for dose estimates should be described in the text in a manner analogous to description of the credibility interval for the risk estimation (given some dose).
CDC and NCI should consider performing a reanalysis of the 131I exposures to the American public that would incorporate new dosimetry-related information from Chernobyl and elsewhere, the contribution of global fallout, a more comprehensive uncertainty analysis, and correction of acknowledged errors in the previous dosimetry. However, the committee does not recommend an expanded study of exposure to radionuclides other than 131I inasmuch as the human doses were much lower than those of 131I, they confer essentially non-detectable increases in individual risk, and the risks are of little public-health significance.
Document location and retrieval
The committee recommends an effort to retrieve and archive additional relevant information about the nuclear-weapons testing program. That means collecting data preserved in various repositories that have not been cataloged and may be in danger of imminent destruction.
CDC should also
Continue its search for documents not held by governmental agencies and take steps necessary to ensure their preservation.
Enroll other government agencies, especially the Department of Defense, in the effort to identify, preserve, and publish information.
Make copies of key documents, the data derived from them, and relevant computer codes or other calculation tools and make them all publicly available, including archiving and providing public access to all the databases and spreadsheets generated by the feasibility study and mentioned in it and its appendixes, together with inputs and calculation tools used for other studies performed for NCI and CDC.
The committee also recommends that CDC urge Congress to declare a government-wide moratorium on the destruction of documents that are potentially pertinent to measuring fallout in the United States and to mandate declassification of historical fallout-related records.
Estimates of cancer and non-cancer risks
The committee recommends that more emphasis be placed on levels of individual risk and the associated uncertainty and less on population risk from collective dose. Although collective dose and population risk may have some public health utility if the doses are significant in the context of doses and risks from other sources, they fail to show the size of the risk that individuals are likely to experience, which is the key consideration for concerned citizens and for most public-health implications. It is also important that the executive summary and text compare putative lifetime risks posed by fallout with risks posed by natural background irradiation and with natural lifetime risks. Such comparisons will help to provide a perspective for the general public to better understand the risks related to fallout.
The potential that the dose-response association might have a substantial upward quadratic component or a threshold should be considered in modeling the risk of leukemia posed by fallout radiation.
There is no evidence that radiation doses of the magnitude sustained from NTS or global fallout cause any of the major non-cancer diseases (cardiovascular, respiratory, digestive or genitourinary). A conclusion to this effect would therefore be appropriate.
Communication with the public about exposure and cancer risk
The committee recommends that CDC follow these steps related to communication issues
Develop a detailed public summary and a communication plan for its distribution. The public summary should provide information that can be readily understood by the lay public, including comparison of background radiation with the radiation doses
discussed in the report of the feasibility study and a description of the important uncertainties (related to dose and risk) that apply to the feasibility study.
Phase information from the feasibility study into the 131I/Nevada Test Site Communication Plan in a timely fashion to give interested American citizens a more complete picture of their exposure to NTS and global fallout with appropriate explanations of relative health risks.
If Option 5 is adopted and important new scientific work develops, produce a timely major educational effort that builds on the efforts of the communication plan for the 131I/Nevada Test Site study.
Make studies on radiation exposure of US citizens transparent and accessible to interested individuals. The committee recommends that interested citizens take part in the study process and, with scientific and social science experts, serve as members of advisory boards for such studies.
Hold a follow-up conference, similar to the one sponsored by NCI on risk communication (January 2000), as part of the continuing CDC effort to develop effective guidelines for communicating radiation risk to the American public.