Life Sciences in the Space Program 



Before the start of long-duration missions, attempts should be made to identify 

 organic or psychological health problems that could threaten the mission. For 

 example, whole-body magnetic resonance imaging should be considered to screen 

 for occult rumors. Also, based upon a probabilistic model of radiation exposure, a 

 crew member may be encouraged to store bone marrow for autologous bone 

 marrow transplant, should that become necessary. To maximize the fidelity of 

 such a model, every effort must be made to measure the relevant radiation 

 environment accurately. 



Operational Medicine has a prime responsibility for inflight occupational health 

 issues, including monitoring the environment and the crew's response to the 

 environment. Detection, identification, modification, and adherence to the limits of 

 spacecraft maximum allowable concentrations (SMAC) for toxic atmospheric 

 contaminants become more important with longer missions, as indicated in 

 "Systems Engineering." SMAC standards need periodic review and revision based 

 on new experience and data. The microbiological atmospheric and surface 

 environments should be continually monitored in a longitudinal manner during 

 long-duration space flight. In addition, the pathogenicity of spacecraft flora in 

 relation to any possible alterations in the host immune system should be evaluated 

 (12). Furthermore, environmental factors, such as temperature, humidity, odor, 

 noise, electromagnetism, and vibration, require scrutiny with respect to health and 

 performance. 



Another high priority item for preventing potential inflight medical problems is 

 perfecting the development of the high-pressure extravehicular activity (EVA) 

 spacesuit. The current suits are pressurized at 4.3 pounds per square inch (psi). 

 The ambient Shuttle pressure is 14.7 psi. To avoid decompression symptoms or 

 bends, prolonged periods of prebreathing 100-percent oxygen are mandatory. This 

 procedure, however, has a major impact on flight operations and still leaves a risk 

 of decompression sickness. The development of a high-pressure EVA suit will, 

 therefore, obviate the need for extended prebreathing and significantly reduce the 

 risk of decompression sickness (13). 



As spacecraft and missions become more complex, human factors issues, 

 including the design of efficient, compatible human-machine interfaces, become 

 critical to crew safety, satisfaction, and performance. Standards for allowable 

 recreational and personal time consonant with mission requirements will need 

 careful attention, for long-duration missions, development of interpersonal 

 relationships among the crew needs particular consideration. Crew members who 

 will be participating in such missions should be trained in communication skills 

 and in techniques for resolving interpersonal conflicts. 



Dietary requirements for prolonged space flight must be established. Any possible 

 dietary manipulations that may help prevent deleterious physiological alterations 

 induced by space flight should be fully explored. To aid in this process, attention 

 should be focused upon developing innovative methods (such as identification ot 

 radio-labeled or naturally occurring markers) for dietary monitoring to determine 

 nutritional and/or physiologic status 





