8
Recommendations
The U.S. Army Surgeon General requested guidance from the Institute of Medicine Committee on Battlefield Radiation Exposure Criteria on the management of military operations in which exposures to effective doses of radiation in a range of up to 700 millisievert occur. The committee has formulated recommendations that cover a number of areas. Some of these areas have already been addressed by the military but are included here because they are important and the report would not be complete without their consideration.
Balancing Future and Present Harm
Current doctrine and risk evaluation by military commanders focus on numbers of acute injuries and fatalities and on those factors that may affect the ability to achieve a military objective. The U.S. Department of Veterans Affairs deals with long-term health effects and disability. A focus on the acute effects from any cause is still largely appropriate for hostile situations, but it discounts or ignores long-term detriment and is inappropriate for less emergent situations in which the military may be asked to participate.
The Army asked the committee to consider exposure to doses of less than 700 mSv. Although no significant acute effects are expected to result from such radiation doses, excess risks of many types of cancer and leukemia have statistically significant associations with doses in this range. Although the long-term effects of radiation are relatively well known, the long-term detriment associated with other exposures or potential exposures, such as psychological stress, are less well understood and quantified. The committee thinks that these should not be ignored.
Recommendation 1: When making decisions, commanders should consider the long-term health effects that any action may have on their troops.
- This should become standard operating policy.
- In addition, the U.S. Department of Defense should attempt to quantify long-term detriments from a number of causes, including radiation, and develop training materials and scenarios that address these effects.
- The long-term effects to be considered when making operational decisions should include not only those from radiation but also those from conventional injuries, chemical and biological agents, and psychological stress.
Philosophy of Radiation Protection
A philosophy for dealing with any potential harm should be clearly stated, widely disseminated, ethically based, practical, and comprehensive. This will allow commanders to make informed decisions and be flexible rather than having to deal with prescribed limits when they may be inappropriate or impractical. This philosophy should be focused on minimizing the risk of harm while allowing the performance of the required military objective. Radiation exposure is clearly justified in some situations because the risk of radiation-induced harm is less than the risks from other hazards associated with the action. A policy that completely avoids radiation exposure is inappropriate and may expose troops, and perhaps others, to greater risks of harm from other, nonradiation, causes.
Recommendation 2: The U.S. Department of Defense should develop and clearly express an underlying philosophy for radiation protection.
-
A.
The committee suggests application and adaptation of the system recommended by the International Commission on Radiological Protection.
- This system includes practices as well as interventions.
- These are required to be initially justified (more benefit than risk) and then optimized (dose minimized) in the context of the situation.
-
B.
The committee recommends that in peacetime or nonemergent situations, soldiers should be accorded the same level of protection accorded civilians.
- Examples of these settings include emergent or lifesaving actions, actions to prevent exposure of large populations, and hostile situations.
C. |
In settings in which an intervention is required and specific numerical dose limits are neither applicable nor practical, the committee recommends that commanders justify the mission (there is more benefit than risk), examine competing risks, and optimize the mission (identify ways to minimize dose without jeopardizing the mission). |
Communicating Risk
Training and risk communication are extremely important not only so the troops can adequately achieve their objective but also so they can understand the risks and can protect themselves.
Recommendation 3: Military personnel should receive appropriate training in both radiation effects and protection. Their training will need to vary on the basis of the particular level of potential exposure and the task at hand.
Radiation Dosimetry, Records, and Reporting
For risk management during and after a mission, it is important to estimate or quantify current and past exposures. This is optimally done through the use of radiation detection devices, environmental sampling, personnel dosimeters, bioassays, and, possibly, whole-body counting. Even in certain hostile situations when all of these may not be possible, estimates of exposure conditions and dose can still be made. Such information should be available to military personnel during active duty and after discharge.
Recommendation 4: A program of measurement, recording, maintenance, and use of dosimetry and exposure information is essential.
-
A.
Troops expected to be in areas where there is a risk of radiation exposure should have individual dosimeters.
-
B.
Systematic individual radiation dose records—external and internal doses—should be maintained and should follow the soldier from one operational unit to another.
-
C.
A system that includes the capability to field monitor, and estimate or measure and then record internal doses needs to be developed.
-
•
When appropriate, organ-absorbed doses should be recorded in addition to the effective dose.
-
D.
The U.S. Department of Defense should also maintain exposure records in a confidential manner that contains strong privacy assurances. Records should be kept in a secure form and should be available to the individual.
-
E.
Annually and upon deactivation or discharge, potentially exposed military personnel should be given a written record of their radiation exposures with estimated doses (annual and cumulative), even if they are zero.
Follow-up
The exposure of troops to agents and situations that may have long-term health effects raises the issue of whether there is any appropriate medical monitoring (screening) that will detect such effects before they are evident clinically and that may positively affect disease progression or outcome. The primary effect in the cumulative radiation dose range that the committee considers in this report is an excess risk of certain types of cancer and leukemia. Unfortunately, at this time only a few screening tests are clearly effective; these tests are used to detect breast, cervical, and colon cancers. Physician-directed individual diagnostic testing may be useful in selected situations, particularly when radiation absorbed doses are extremely high. It should be noted that cancer occurs in about 40 percent of the U.S. population (NCI, 1994). For doses in the highest dose range addressed in this report (500-700 mSv), the increased risk of cancer attributable to the radiation dose is about 1/10 the normal baseline incidence rate for unexposed individuals. Although this is a low percentage, a large number of troops exposed at these doses could result in a large number of excess cancers.
Recommendation 5: Given the tests that are currently available, and their limitations, testing and monitoring programs for cancer (whether spontaneous or radiogenic) should be limited to those testing and monitoring programs included in guidelines for the general population.
- Specific periodic screening or medical monitoring of radiation exposed populations is not warranted solely on the basis of radiation exposure in the dose range considered in this report.
- If effective tests for other cancer types do become available, screening may be useful on the basis of the normal cancer incidence in the general population.
- For persons who have received cumulative effective doses in excess of 50 mSv, the establishment of well-designed and dynamic registries may be helpful in addressing future health-related issues on an individual or population basis.