origin into Earth's biosphere. The amount of material to be returned is too small to pose any concern about possible toxicity, and any potential danger to researchers analyzing the samples would be obviated by standard laboratory control procedures.
Another question posed to the task group was what scientific investigations could be undertaken to reduce uncertainty regarding the possibility of extant life on Mars. This topic is addressed in Chapter 5. The task group was also asked to assess the status of technical measures for preventing the return of uncontained and unsterilized material of martian origin and, finally, to recommend criteria for controlled distribution of sample material. Technical measures that might be deployed to reduce the risk of loss of containment of sample material are discussed in Chapter 9. No attempt has been made to be comprehensive in this regard as it is recognized that NASA is a preeminent engineering organization, and its technical expertise far outstrips that of the task group.
With regard to criteria for controlled distribution of sample material, the need is clear. In order to maximize the scientific return of a sample return mission, the sample material must be distributed to research centers with particular analytic capabilities. The task group has made several recommendations (see Chapters 4 and 6) with respect to sample containment, handling, and controlled distribution. Detailed protocols for controlled distribution ultimately will be the responsibility of an oversight panel that includes representation from other federal agencies (see Chapter 8) together with the science team associated with the sample-receiving facility (see Chapter 7).