The IOM (1995a, p. 13) study also noted that, ''Although there is anecdotal evidence that individual doses may have been greatly underestimated in individual cases, the overall tendency may have been to overestimate both external and internal doses.'' Even so, the doses of record for the CROSSROADS participants are comparable in magnitude and variability to the additional doses received in one decade by residents of the Rocky Mountain region as compared with those received by residents of the rest of the United States. The lifetime doses received by CROSSROADS participants are well within the range of lifetime doses to the U.S. population resulting from naturally occurring radiation sources.
It is conceivable that a subset of the CROSSROADS participants, because of their specialized training, may have pursued careers in radiation sciences either within the services or as civilians (e.g., as health physicists, nuclear reactor operators, or nuclear engineers). It is probable that this group accrued substantially higher radiation doses after CROSSROADS than during the test itself. We have no means of controlling for this possibility.
Although the radiation doses to the CROSSROADS cohort appear low, veterans have been vocal in their assertions that they are significantly below what they should be, based upon their firsthand observations of conditions at the test site. That makes it all the more desirable that this study base its analyses on exposure factors other than these dose estimates.
A summary of the DNA-assigned doses for the boarding and occupational specialty categories are shown in Figure D-1 and Table D-1. Again, note that these categories were derived independent of any dose information.