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C Committee Reviews of the Evidence Books Sensorimotor Chapter 1 Impaired Ability to Maintain Control of Vehicles and Other Complex Systems Bone Chapter 2 Accelerated Osteoporosis Chapter 3 Bone Fracture Chapter 4 Renal Stone Formation Chapter 5 Intervertebral Disk Damage Muscle Chapter 6 Impaired Performance Errors Due to Reduced Muscle Mass, Strength, and Endurance Chapter 7 Operational Impact of Prolonged Daily Required Exercise Chapter 8 Compromised EVA Performance and Crew Health Due to Inadequate EVA Suit Systems Cardiovascular Chapter 9 Orthostatic Intolerance During Re-Exposure to Gravity Chapter 10 Cardiovascular Effects on Performance and Operational Limi- tations Chapter 11 Cardiac Rhythm Problems 31

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32 REVIEW OF NASA’S HUMAN RESEARCH PROGRAM EVIDENCE BOOKS Nutrition Chapter 12 Inadequate Nutrition Immunology Chapter 13 Crew Adverse Health Event Due to Altered Immune Response Behavioral Health and Performance Chapter 14 Performance Errors Due to Sleep Loss, Circadian Desynchro- nization, Fatigue, and Work Overload Chapter 15 Performance Errors Due to Poor Team Cohesion and Perform- ance, Inadequate Selection/Team Composition, Inadequate Training, and Poor Psychosocial Adaptation Chapter 16 Behavioral and Psychiatric Conditions Space Radiation Chapter 17 Acute Radiation Syndromes Due to Solar Particle Events Chapter 18 Degenerative Tissue or Other Health Effects from Radiation Exposure Chapter 19 Acute or Late Central Nervous System Effects from Radiation Exposure Chapter 20 Radiation Carcinogenesis Pharmacology Chapter 21 Therapeutic Failure Due to Ineffectiveness of Medication Exploration Medical Capabilities Chapter 22 Inability to Adequately Treat an Ill or Injured Crew Member Space Human Factors and Habitability Chapter 23 Lack of Human-Centered Design A. Sub-Risk of Reduced Safety and Efficiency Due to Poor Human Factors Design B. Sub-Risk of Error Due to Inadequate Information C. Sub-Risk Associated with Poor Task Design Chapter 24 Inadequate Food System Chapter 25 Adverse Health Effects from Lunar Dust Exposure

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33 APPENDIX C Chapter 1 Impaired Ability to Maintain Control of Vehicles and Other Complex Systems Does the evidence book make the case (sufficient evidence) that this risk is relevant to long-term space missions? Yes. Experimental and observational findings from prior missions, including Apollo, aviation, ground-experimental, and patient data are quite thoroughly described. Additional data and discussions would be helpful to add as described below. Is the text of the short description of the health risk provided in the PRD)clear (it should be Section I of the evidence book)? Provide suggestions of revised wording. Yes. However, an additional sentence relating the risk to existing Apollo data would be helpful. Does the evidence book make the case for the research gaps presented? Yes. The paper presents a comprehensive review of the literature. The implica- tions for future lunar and Mars missions are clearly spelled out. The documenta- tion in the appendix of apparently all U.S. and Russian neurological and sensorimotor experiments conducted in space is highly informative. Additional risks to be considered for review in this paper include the possible impact of alterations in cortical maps of motor control and somatosensation, and the physiologically relevant factors associated with cognitive and sensorimotor adaptations to abnormal force conditions. Are there any additional gaps in knowledge that should be considered for this specific risk? Yes, there should be some discussion of the relationship to the basic perform- ance measures (reaction time, short-term memory, etc.) in spaceflight. A discus- sion of fractional g-levels and sensorimotor adaptation is also needed. Does the evidence book address relevant interactions among risks? Yes. A consideration of sleep deprivation and stress effects on sensorimotor performance is indicated. Comment if relevant to the specific evidence book: Is the merging of some risks in the Bioastronautics Roadmap into a single risk appropriate? Is the omission of some risks in the Bioastronautics Roadmap appropriate? These are not relevant to this evidence book.

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34 REVIEW OF NASA’S HUMAN RESEARCH PROGRAM EVIDENCE BOOKS Comment on other issues regarding the evidence book, including: • Is the author expertise sufficient? Other disciplines needed? • Literature search: Is the breadth of the search sufficient? Is informa- tion on the search strategy needed? • Overall readability: Is it appropriate for a “science professional” who is not familiar with the specific area covered? The paper is highly readable, scholarly, and quite comprehensive in its coverage. The amount of material covered and the implications of the findings for future lunar and Mars missions are highly informative. The paper clearly specifies the potential risks in future space activities based on the sensorimotor deficit find- ings from previous studies. It would be helpful if the paper had a discussion of the caveats relevant to assessing the reliability of data from these types of space flight experiments that involve few subjects and lack adequate controls. A more thorough review of the literature on vestibulo-ocular reflex function could be added. The committee had concerns that the section on tilt translation and tilt gain illusions seems exceedingly long given the sparse information actu- ally available. Discussions of the issues regarding the theories that are proposed to explain these illusions should be added, as should a discussion of oculogravic illusions. The section on computer-based simulation information presents a number of the classic early studies in the field but more recent modeling data need to be described (data based on more biological considerations than on analogies with inertial guidance systems). Future reviews would benefit from a more diverse group of contributors that could add a focus on these additional topics. Minor issue: There is an error in the table of contents in which “Risk of Accelerated Osteopo- rosis” is listed as the title of the risk. Overarching comments on the evidence book: Provide a short paragraph summary of the key issues raised in your review of the paper. The paper provides a clear and succinct review of the space and other literature related to sensorimotor problems during and after spaceflight. The extrapolation of these data to potential risks in vehicle control for lunar and Mars missions is informative, particularly discussions about landing a vehicle on the Mars sur- face. The issue of predictors of astronaut performance from preflight measures is highly relevant.

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35 APPENDIX C Please note: • Crosscutting issues and ideas for broader recommendations • Additional risks that should be added to the list (missing risks) Space motion sickness should still be considered an unsolved risk, and there is ample reason to keep it on the gap and critical path lists. Chapter 2 Accelerated Osteoporosis Does the evidence book make the case (sufficient evidence) that this risk is relevant to long-term space missions? Generally, yes. The evidence book is an excellent review and analysis of the evidence. Some areas deserve additional comment, at least in part because they may lead to the identification of more knowledge gaps. 1. Although mentioned, the considerable heterogeneity in the rate of bone loss is of potentially huge importance, and should be further emphasized. Some flight personnel apparently experience particularly rapid bone loss, and these individuals may be at particular risk. Are flights imperiled more by the astronauts with greatest bone loss rather than the average bone loss of the crew? As the evidence book notes, there is also heterogeneity in the de- gree of recovery from bone loss after landing. 2. The evidence book mentions the lack of evidence concerning the effects of long-term flight (> 6 months) on bone, but fails to discuss the relevant data concerning long-term spinal cord injury (SCI). One of the potential failings of the comparison of bone loss in spaceflight to menopause is that it could lead to the assumption that the bone loss in space is self-limited. On the other hand, long-term SCI studies suggest that bone loss continues for long periods after immobilization begins and results in truly dramatic reductions in bone mass. Moreover, some data indicate that markers of bone resorption remain elevated for long periods, further raising the concern that accelerated bone loss could be prolonged with more impressive implications for long- term flights. These considerations seem important to discuss. See the re- views of SCI and bone by Giangregorio and Blimkie (2002) and Jiang et al. (2006). 3. The paper concentrates on the effects of the unloading that accompanies weightlessness, but little attention is given to known or possible effects of long-term reduced gravity environments such as those that might be experi- enced with future lunar missions. 4. A discussion of the potential biomechanical trauma anticipated on bone during flight and planetary/lunar stays seems important. Although it could also be presented in the evidence book on fractures (and just referenced in this section), the current evidence book does a good job of presenting finite

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36 REVIEW OF NASA’S HUMAN RESEARCH PROGRAM EVIDENCE BOOKS element analyses of the strength of bone, and the corollary of that discus- sion is that of the load-to-strength ratio (factor of risk). In other words, is the level of trauma risk anticipated (load) likely to be greater than the ability of the weakened bone to resist it (strength)? The issue of trauma would seem relevant given the possibility of flight turbulence, landing, and extra- vehicular excursions. Are there forms of trauma expected that might affect specific bones, and are those bones particularly weakened (e.g., hip)? In ad- dition to the possibility of trauma from factors such as turbulence, it may be worth mentioning the possibility of physical stresses from tasks requiring forceful movements and torque (although such tasks might be more likely to put stress on the upper extremities, where the bone changes are not as great). Should space suits or in-flight clothes contain force-mitigating pads during long flights? The degree of concern for in-flight fracture ultimately rests on the ability of the bones on the flight (and potentially the weakest bones) to resist the extant trauma. 5. The emphasis on unloading as the etiology of bone loss is necessary and appropriate, but the other potential causes of bone loss during missions may deserve more discussion. Although unloading is undoubtedly a dominant factor, other possible contributors to bone loss could be considered. These include chronic stress, weight loss, sleep disturbance, gonadal abnormali- ties, etc. Some of these are suspected to be problems, while others have not been examined. The possibility that unexpected effects on bone may be en- countered during spaceflight should not be ignored. More discussion is war- ranted. This may deserve special attention in light of the interindividual variation in bone loss. The factors mentioned, such as chronic stress and sleep disturbance, would be expected to vary substantially from person to person. 6. In the introduction, the authors appropriately point out that, despite their use of the menopausal and aging comparisons, that spaceflight is neither of those things. However, the possibility that spaceflight causes a distinct form of metabolic bone disease should be more carefully considered. For exam- ple, spaceflight is not like postmenopausal osteoporosis because there may be an absolute (or more marked) reduction in bone formation during flight whereas postmenopausal bone loss is characterized by increased bone for- mation (with an even more increased rate of resorption). If the nature of flight-induced bone loss is different from the aging or postmenopausal con- ditions, perhaps more akin to glucocorticoid-induced bone loss (where— like spaceflight—there is also a state of increased bone resorption and re- duced bone formation), it could result in an altered fracture threshold. An- other example of differences may be that hip bone loss seems to out of proportion to that seen in postmenopausal women, apparently indicating distinct pathophysiological mechanisms. Should these and other potential differences be examined to best understand how to mitigate risk?

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37 APPENDIX C 7. Bone strength is the result of a number of factors, including the amount of bone, its structure, and its quality. The evidence book should mention the possibility that bone material properties could be altered by flight. Some data from the SCI literature indicate that bone formation is altered, poten- tially affecting material properties and strength. 8. Efforts undertaken so far to prevent bone loss during flight, and their effec- tiveness, should be discussed. 9. The recent occurrence of a hip fracture in a previous astronaut is potentially important, especially because traumatic fractures are highly related to lower bone mineral density (BMD) (Mackey et al., 2007). Perhaps this should be presented. Is the text of the short description of the health risk provided in the PRD clear (it should be Section I of the evidence book)? Provide suggestions of revised wording. 1. “…unloading of the skeleton. In moderate-duration flights (6 months) aver- age loss rates are approximately 1 percent per month, but some individuals lose at a greater rate. It is unclear whether this bone mineral loss will stabi- lize at a lower level or continue for the duration of longer flights. The cau- sation and specific nature of the loss are unknown. Efforts to devise methods to prevent loss during flight have not been successful. Mission- related bone loss…” 2. Also, the statement that “mission-related bone loss cannot be corrected by. . . ” may be too strong. Perhaps “ . . . cannot be reliably . . . ” or “ . . . cannot be completely . . . ” would be more correct. Does the evidence book make the case for the research gaps presented? Yes, there is an excellent presentation of research gaps. Are there any additional gaps in knowledge that should be considered for this specific risk? Additional gaps to be considered include: 1. Does the loss of bone during flight result in structural alterations that are unique (different from the aging or postmenopausal states) that have distinct biomechanical implications? 2. Apart from unweighting, the factors that contribute to bone loss are un- clear. 3. The effects of long-term flight on bone are unknown (the authors clearly note this, but it is not listed as a gap). 4. The preflight or during-flight factors that affect the rate of bone loss during flight are unknown.

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38 REVIEW OF NASA’S HUMAN RESEARCH PROGRAM EVIDENCE BOOKS 5. The expected forces (trauma) that may be exerted on bone during flight or extravehicular activity are unknown. The bones at particular risk are unknown. 6. The best methods for measuring bone structure and strength are not known. 7. The usefulness of new bone formation drugs are not known—either during flight or after return to Earth. 8. In-flight metabolic alterations that could affect bone are not known. Does the evidence book address relevant interactions among risks? Some possibilities are as follows: 1. The risk of renal stones from increased bone resorption is noted, but other possible problems may flow from alterations of bone metabolism. For instance, there are probably vitamin D reductions during flight, and muscle strength is reduced by vitamin D insufficiency. The danger of hypercalcemia is clearly increased in SCI (especially under certain cir- cumstances, such as dehydration). Hypercalcemia has been linked to nausea, mental status and mood abnormalities, cardiac arrhythmias, etc. 2. Nutrition is an area of potential overlap. 3. Human Factors Design and Task Design are areas of potential overlap. Comment if relevant to the specific evidence book: Is the merging of some risks in the Bioastronautics Roadmap into a single risk appropriate? Is the omission of some risks in the Bioastronautics Roadmap appropriate? These are not relevant to this evidence book. Comment on other issues regarding the evidence book, including: • Is the author expertise sufficient? Other disciplines needed? • Literature search: Is the breadth of the search sufficient? Is informa- tion on the search strategy needed? • Overall readability: Is it appropriate for a “science professional” who is not familiar with the specific area covered? o Author expertise appropriate: The authors are outstanding. An ex- pert in mineral metabolism and related endocrine issues would be useful. A bone biomechanic would provide benefit, and an expert in human factors engineering may be useful. o Literature presented; generally very good. As noted previously, additional areas of interest would be the long term effects of SCI and bone/mineral endocrinology. o Overall readability: excellent. Overarching comments on the evidence book: Provide a short paragraph summary of the key issues raised in your review of the paper. Key issues raised include:

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39 APPENDIX C 1. Concern about overreliance on the models of postmenopausal and age- related bone loss. 2. A minimal emphasis on the heterogeneity of bone loss, and the implica- tions of the “weakest link” consideration. 3. Need for linking the strength of bone to the trauma expected during flight. 4. The paucity of good data concerning the metabolic/environmental ab- normalities potentially contributing to bone loss (apart from unweight- ing). Please note: • Crosscutting issues and ideas for broader recommendations • Additional risks that should be added to the list (missing risks) Other risks: The possibility of metabolic disturbances resulting from accelerated bone remodeling/loss (vitamin D deficiency, hypercalcemia). REFERENCES CITED Giangregorio, L., and C. J. Blimkie. 2002. Skeletal adaptations to alterations in weight-bearing activity: A comparison of models of disuse osteoporosis. Sports Medicine 32(7):459-476. Jiang, S. D., L. Y. Dai, and L. S. Jiang. 2006. Osteoporosis after spinal cord injury. Osteoporosis International 17(2):180-192. Mackey, D. C., L. Y. Lui, P. M. Cawthon, D. C. Bauer, M. C. Nevitt, J. A. Cauley, T. A. Hillier, et al. 2007. High-trauma fractures and low bone min- eral density in older women and men. Journal of the American Medical As- sociation 298(20):2381-2388. Chapter 3 Bone Fracture Does the evidence book make the case (sufficient evidence) that this risk is relevant to long-term space missions? Yes. In general the evidence book is a scholarly and complete examination of the issue. There are additional knowledge gaps that should be considered. Is the text of the short description of the health risk provided in the PRD clear (it should be Section I of the evidence book)? Provide suggestions of revised wording. Yes, in general the short description is clear and complete. Consider a final sen- tence “Additional data is needed to understand the alterations in bone biology

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40 REVIEW OF NASA’S HUMAN RESEARCH PROGRAM EVIDENCE BOOKS that could increase the potential for stress fracture or impaired fracture healing in flight.” Does the evidence book make the case for the research gaps presented? Yes. The research gaps identified are well substantiated. Are there any additional gaps in knowledge that should be considered for this specific risk? Yes. Additional gaps in knowledge to be considered include: 1. The evidence book concentrates on fracture risk during flight. Although this is an appropriate concern, there is less attention paid to the risks of fracture after return from flight. As there have been several fractures now in previous astronauts, and the to-some-extent irreversible bone loss associated with flight is well known, post-flight fracture risk should be more prominently considered. 2. Fracture due to severe trauma is prominently considered (as it should be) but there may be additional mechanisms of potential importance (particularly in a situation associated with low bone formation). One is stress fracture due to repetitive lower level force. Unusual stress and impaired responses to it may be encountered during flight/EVA. An- other may be static forces and torque or torsional forces during mission activities such as construction tasks or EVAs. 3. In addition to the biomechanically oriented fracture risks considerations included in the evidence book, some attention should be paid to frac- ture healing in space. There is evidence to suggest that remodeling is altered, but little data concerning the adequacy of healing. Certainly, if a fracture occurs during flight, inadequate healing would add to the problem. Does the evidence book address relevant interactions among risks? Related risks that were not addressed. They might include: 1. Reduced muscle mass 2. Poor human factors design 3. Bone loss 4. Impact of prolonged exercise 5. Inability to provide clinical treatment 6. Nutrition 7. Poor task design 8. Orthostatic intolerance

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41 APPENDIX C Comment if relevant to the specific evidence book: Is the merging of some risks in the Bioastronautics Roadmap into a single risk appropriate? Is the omission of some risks in the Bioastronautics Roadmap appropriate? These are not relevant to this evidence book. Comment on other issues regarding the evidence book, including: • Is the author expertise sufficient? Other disciplines needed? • Literature search: Is the breadth of the search sufficient? Is informa- tion on the search strategy needed? • Overall readability: Is it appropriate for a “science professional” who is not familiar with the specific area covered? Additional expertise in fracture biology and in human factors engineering (to give more full attention to the relationship between environmental design and physical stress on bones and joints) might be helpful. The literature search is complete. Readability is good. Overarching comments on the evidence book: Provide a short paragraph summary of the key issues raised in your review of the paper. In general the evidence book is excellent. Additional attention should be di- rected at postflight fracture risk, fracture healing during low-G situations, and the possibility of stress fracture. Although there are distinct features of this evidence book on fracture risk, it could be argued that it could be combined with that on bone loss. Two minor issues: 1. Figure 3-1 may have an error. The aBMD ascribed to the three bone ge- ometries is consistently 1, but in fact the aBMD is progressively lower going left to right. 2. On p. 3-9 it is noted that “ . . . planetary surfaces provide unique scenar- ios that may: - reduce the forces applied to bone structures.” In fact, planetary surfaces may increase forces when considered in comparison to previous 0 G conditions. That could be a critical consideration regarding frac- ture risk. Please note: • Crosscutting issues and ideas for broader recommendations • Additional risks that should be added to the list (missing risks) No additional comments.

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80 REVIEW OF NASA’S HUMAN RESEARCH PROGRAM EVIDENCE BOOKS based solely on existing in-mission and analog environment experience is likely to be insufficiently effective, and should be enhanced by best available synthesis of the other health risk categories. For example, although altered immunity has yet to be associated with clinically evident disease, consideration of treatments of conditions that might result from altered immunity, such as disseminated viral reactivation, should be included in planning for long-term missions. Does the evidence book address relevant interactions among risks? No. Inability to provide treatment is interlinked with “risk of error due to inade- quate information.” Comment if relevant to the specific evidence book: Is the merging of some risks in the Bioastronautics Roadmap into a single risk appropriate? Is the omission of some risks in the Bioastronautics Roadmap appropriate? These are not relevant to this evidence book. Comment on other issues regarding the evidence book, including: • Is the author expertise sufficient? Other disciplines needed? • Literature search: Is the breadth of the search sufficient? Is informa- tion on the search strategy needed? • Overall readability: Is it appropriate for a “science professional” who is not familiar with the specific area covered? The paper is quite readable and well formulated, with adequate citations to pub- lished and unpublished findings. Author expertise appears to be appropriate to the task. Overarching comments on the evidence book: Provide a short paragraph summary of the key issues raised in your review of the paper. This evidence book seems to be in an early stage of development. The addition of a detailed list of gaps will do much to illuminate the directions in which re- search and development will be going within NASA. As written, it describes a necessary, but not sufficient, overall approach to the provisioning of autono- mous health care resources and, at least as importantly, the enumeration of con- ditions that will be left untreated during exploration-class missions. Please note: • Crosscutting issues and ideas for broader recommendations • Additional risks that should be added to the list (missing risks) No additional comments.

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81 APPENDIX C Chapter 23A Lack of Human-Centered Design: Sub-Risk of Reduced Safety and Effi- ciency Due to Poor Human Factors Design Does the evidence book make the case (sufficient evidence) that this risk is relevant to long-term space missions? Yes. The case is made largely on the basis of anecdotal incidents that are con- vincing, but not a thorough scientific evaluation. The numerous examples are compelling, but it would be a stronger case if they were limited to the space ac- cidents rather than the ground-based accidents (e.g., aviation, ship, power plant) as well. It is far more important to demonstrate the problems that exist in long- duration spaceflight and the research required to address those problems than it is to describe the effects of general human accidents in recent history. Is the text of the short description of the health risk provided in the PRD clear (it should be Section I of the evidence book)? Provide suggestions of revised wording. No. Although the case is strong, the description is inadequate. It is filled with jargon and is not specific. Does the evidence book make the case for the research gaps presented? Yes. Are there any additional gaps in knowledge that should be considered for this specific risk? Yes. Additional gaps in knowledge to be considered include: 1. Manual control 2. Advanced displays 3. Workload assessment 4. Training, both initial and in-mission 5. Use of artificial intelligence for malfunctions 6. Spatial disorientation as it affects performance Does the evidence book address relevant interactions among risks? Yes. With human factors, everything is connected to everything else. A fatigued astronaut will need a redundant checklist. A disoriented one will need a more compelling display. Further, the authors may wish to address the potential over- lap associated with the impact of environmental design on psychosocial and behavioral adjustment issues, e.g., issues discussed in Chapters 15 and 16. Comment if relevant to the specific evidence book: Is the merging of some risks in the Bioastronautics Roadmap into a single risk appropriate? Is the omission of some risks in the Bioastronautics Roadmap appropriate? These are not relevant to this evidence book.

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82 REVIEW OF NASA’S HUMAN RESEARCH PROGRAM EVIDENCE BOOKS Comment on other issues regarding the evidence book, including: • Is the author expertise sufficient? Other disciplines needed? • Literature search: Is the breadth of the search sufficient? Is informa- tion on the search strategy needed? • Overall readability: Is it appropriate for a “science professional” who is not familiar with the specific area covered? The literature should be divided into the specific accounts associated with the Human Factors examples, and the broader references dealing with space experi- ences and human factors methodology. The expertise and examples are ade- quate, though not all are directly applicable. The overall readability is poor because of too much jargon and too much repetition. The evidence book list of authors includes many from “inside” the NASA system, and may be improved with additional external academic perspectives. Overarching comments on the evidence book: Provide a short paragraph summary of the key issues raised in your review of the paper. This section is a full and provocative primer on the general issue of dangers as- sociated with the various aspects of human-centered design, and what can hap- pen if the principles are ignored. It suffers from being too long—but especially in not distinguishing between the dangers associated with the failure to follow known procedures, and the absence of information about what procedures to employ for long-duration spaceflight. The first is a matter of training and the second is the subject for NASA’s Human Research Program (HRP) research. Please note: • Crosscutting issues and ideas for broader recommendations • Additional risks that should be added to the list (missing risks) 1. Manual control 2. Displays 3. Spatial disorientation 4. Fatigue Chapter 23B Lack of Human-Centered Design: Sub-Risk of Error Due to Inadequate Information Does the evidence book make the case (sufficient evidence) that this risk is relevant to long-term space missions? Yes. As discussed below; however, the case could be made more compelling. Is the text of the short description of the health risk provided in the PRD clear (it should be Section I of the evidence book)? Provide suggestions of revised wording.

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83 APPENDIX C Yes. It is clear. but incomplete. “Lack of information can be a problem, but so can too much information if the means of separating the important information are inadequate or poorly designed.” A suggested revision follows: “Task errors can be due to lack of, or inadequate ability to dis- cern, appropriate information, which in turn may be due to any of the following: [(a), (b), (c), (d) as shown] (e) excessive information, with unclear or otherwise inade- quate demarcation between the information that is important or useful for the situation and the information that is not.” Does the evidence book make the case for the research gaps presented? Yes. The supporting evidence from spaceflight is very strong, and NASA is cer- tainly one of the world’s leading experts. However, the categorization of the spaceflight examples could have been more logically presented in some in- stances. The ground-based supporting evidence is not adequate. For example, using an occurrence that is nearly 30 years old (the Three Mile Island nuclear accident in Pennsylvania) as an example of inadequate displays and controls certainly raises the question of whether there are more recent examples. If so, these should be cited as examples, and if not, query whether a problem still ex- ists. In addition, because the risk definition does not adequately address having too much information, none of the examples relates to that issue. There is a large amount of supporting ground-based evidence that is available concerning every category enumerated in the evidence book, involving both inadequate and too much information. The evidence book would be stronger if such issues were also included. Are there any additional gaps in knowledge that should be considered for this specific risk? Yes. There are undoubtedly gaps associated with the issue of too much informa- tion, which is not adequately discussed in the report. Does the evidence book address relevant interactions among risks? Yes. Comment if relevant to the specific evidence book: Is the merging of some risks in the Bioastronautics Roadmap into a single risk appropriate? Is the omission of some risks in the Bioastronautics Roadmap appropriate? These are not relevant to this evidence book. Comment on other issues regarding the evidence book, including: • Is the author expertise sufficient? Other disciplines needed?

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84 REVIEW OF NASA’S HUMAN RESEARCH PROGRAM EVIDENCE BOOKS • Literature search: Is the breadth of the search sufficient? Is informa- tion on the search strategy needed? • Overall readability: Is it appropriate for a “science professional” who is not familiar with the specific area covered? No additional comments. Overarching comments on the evidence book: Provide a short paragraph summary of the key issues raised in your review of the paper. The paper satisfactorily addresses issues associated with inadequate information, but the paper should also address issues associated with too much information, which can also lead to undesirable outcomes. Please note: • Crosscutting issues and ideas for broader recommendations • Additional risks that should be added to the list (missing risks) No additional comments. Chapter 23C Lack of Human-Centered Design: Sub-Risk Associated with Poor Task Design Does the evidence book make the case (sufficient evidence) that this risk is relevant to long-term space missions? Yes. As discussed below, however, the case could be more compelling. Is the text of the short description of the health risk provided in the PRD clear (it should be Section I of the evidence book)? Provide suggestions of revised wording. Yes. It is clear but incomplete. Focusing solely on reducing operator error is politically popular, but can result in serious inefficiencies when applied in actual operation. Moreover, the issue relates to all tasks, not just critical tasks. A sug- gested revision to the second sentence follows: “All tasks, especially critical tasks, must be designed to minimize human error in a way that improves effi- ciency as much as possible, or at least minimally degrades efficiency.” Does the evidence book make the case for the research gaps presented? Yes. Similar to Chapter 23B: Inadequate Information, the supporting evidence from spaceflight is very strong, and NASA is certainly one of the world’s lead- ing experts. However, the categorization of the spaceflight examples could have been more logically presented in some instances. The ground-based supporting evidence is not adequate. For example, using an occurrence that is more than 60 years old (a cargo ship explosion in 1947) as an example of which cargo com- partments should and should not be adjacent to each other (not to mention the

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85 APPENDIX C issue of why this is an example of poor task design) certainly raises the question of whether there are better and more recent examples. If so, why aren’t more recent examples cited, and if not, query whether this is still a problem. Are there any additional gaps in knowledge that should be considered for this specific risk? Yes. There are gaps associated with determining the impact on efficiency of an error-reducing task design. Does the evidence book address relevant interactions among risks? No. The design of tasks that necessitate EVA must consider the physical and other limitations created by the EVA suit. Comment if relevant to the specific evidence book: Is the merging of some risks in the Bioastronautics Roadmap into a single risk appropriate? Is the omission of some risks in the Bioastronautics Roadmap appropriate? These are not relevant to this evidence book. Comment on other issues regarding the evidence book, including: • Is the author expertise sufficient? Other disciplines needed? • Literature search: Is the breadth of the search sufficient? Is informa- tion on the search strategy needed? • Overall readability: Is it appropriate for a “science professional” who is not familiar with the specific area covered? No additional comments. Overarching comments on the evidence book: Provide a short paragraph summary of the key issues raised in your review of the paper. The paper should address not only the error potential of task designs, but also the impact on efficiency. In addition, task design of activities that involve EVA must also consider the physical and other limitations of the EVA suit. Please note: • Crosscutting issues and ideas for broader recommendations • Additional risks that should be added to the list (missing risks) No additional comments. Chapter 24 Inadequate Food System Does the evidence book make the case (sufficient evidence) that this risk is relevant to long-term space missions? Yes.

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86 REVIEW OF NASA’S HUMAN RESEARCH PROGRAM EVIDENCE BOOKS Is the text of the short description of the health risk provided in the PRD clear (it should be Section I of the evidence book)? Provide suggestions of revised wording. No. The last sentence suggests that an allocation of resources for food has al- ready been made, which is unlikely at this early stage. The following is a sug- gested replacement for the last sentence: “Furthermore, careful attention must be paid to the resources allocated to creating a satisfactory food system in order to avoid unduly depriving other systems of needed resources.” Does the evidence book make the case for the research gaps presented? Yes. Are there any additional gaps in knowledge that should be considered for this specific risk? Yes. One gap that is not mentioned is whether acceptable food will grow on Mars, the Moon, or enroute, given the reduced gravity, reduced sunlight, avail- able water, radiation, and other aspects of the growing environment. This uncer- tainty may necessitate carrying enough on-board food to provide adequate and acceptable nutrition in case biogeneration is not successful. If enough on-board nutrition has to be carried, as a contingency, a potential query is whether bio- generation should be part of the overall nutrition plan. Does the evidence book address relevant interactions among risks? No. The paper addresses several interactions, most notably the relation between adequate and acceptable food and the crew’s physical and mental well-being, but at least one risk interaction is missing. The evidence book on central nervous system effects from radiation exposure mentions some dietary countermeasures, but there is no indication in this food system paper regarding giving any special consideration to those dietary items. Comment if relevant to the specific evidence book: Is the merging of some risks in the Bioastronautics Roadmap into a single risk appropriate? Is the omission of some risks in the Bioastronautics Roadmap appropriate? These are not relevant to this evidence book. Comment on other issues regarding the evidence book, including: • Is the author expertise sufficient? Other disciplines needed? • Literature search: Is the breadth of the search sufficient? Is informa- tion on the search strategy needed? • Overall readability: Is it appropriate for a “science professional” who is not familiar with the specific area covered? No additional comments.

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87 APPENDIX C Overarching comments on the evidence book: Provide a short paragraph summary of the key issues raised in your review of the paper. The paper provides a good description and analysis of the many difficult issues involved. Please note: • Crosscutting issues and ideas for broader recommendations • Additional risks that should be added to the list (missing risks) No additional comments. Chapter 25 Adverse Health Effects from Lunar Dust Exposure Does the evidence book make the case (sufficient evidence) that this risk is relevant to long-term space missions? No. 1. The evidence book would be strengthened by the addition of a system- atic introduction to the toxicology of airborne particulates, so that the reader would have a set of benchmarks against which the evidence re- garding lunar dust can be considered. As a related consequence, the document jumps from one topic to another, including some examples (e.g., Hawks Nest tunnel disaster) that have little relevance for the task at hand. It makes the assumption that activation/passivation is the key issue, but does not adequately justify this. The draft does not do an adequate job of presenting and discussing the potential health effects of dust exposure. These would include at least fibrogenicity, carcinogenic- ity, allergic sensitization, and respiratory/dermal irritant properties. 2. This evidence book should include a more complete and systematic presentation concerning what is known about the characteristics of lu- nar dust in order to consider adequately the potential health risks. This is another prerequisite for an evaluation of risk and gaps. The human health risks from airborne dust exposure vary according to chemical composition, particle size, physical characteristics (e.g., crystalline structure, particle shape, fibrous character), and a variety of human fac- tors (e.g., pre-existing illness, respiratory rate). As an example, the draft paper seems to presume that lunar dust is respirable (see first sen- tence of executive summary), but there is no discussion about the parti- cle size distribution of lunar dust and not all evidence supports this assumption. More attention is necessary for this important issue. 3. Similarly, the current draft fails to consider potential allergic/immune consequences of lunar dust. Indeed, terms such as “airborne allergen” and “IgE” never appear, and the word “immune” (or related) appears only once. This is despite the evidence that two individuals who were

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88 REVIEW OF NASA’S HUMAN RESEARCH PROGRAM EVIDENCE BOOKS exposed to lunar dust reported allergic symptoms or findings. The first, an Apollo astronaut, described his response as “hay fever” (i.e., pollen allergy); the second, a ground-based physician-scientist, described an “allergic-type” reaction, apparently supported by changes in basophil and eosinophil counts. This oversight should be considered and ad- dressed to ensure the development of effective countermeasures. 4. The draft offers two Earth-based analogs (silicosis among miners and volcanic ash exposure) without convincingly explaining how these compare with possible lunar dust exposures. It fails to explore another body of evidence that may be relevant—environmental exposure to PM10 particulate dust (10µM-diameter particulate matter) and its effect on respiratory and cardiovascular function. Is the text of the short description of the health risk provided in the PRD clear (it should be Section I of the evidence book)? Provide suggestions of revised wording. No. The text is not an affirmative statement describing the problem. Rather it is simply a critique of the risk statement in the PRD. It is suggested that it be re- written, not just revised. Does the evidence book make the case for the research gaps presented? Yes. Most of the gaps identified seem reasonable; however, the paper may be strengthened if it begins to establish relative importance to each. Are there any additional gaps in knowledge that should be considered for this specific risk? Yes. Additional gaps in knowledge to be considered include: 1. Respiratory dynamics under conditions of reduced gravity or weight- lessness. Does particle distribution and deposition in the respiratory tract differ from Earth-based conditions? 2. Effectiveness of available control methods to reduce exposure. 3. Role of lunar dust as a possible airborne allergen. 4. Countermeasure development, ranging from physical to pharmaceuti- cal, to deal with the airborne allergen potential. Does the evidence book address relevant interactions among risks? No. Only EVA suits are mentioned. Other topics for consideration include im- pact of prolonged exercise, poor human factors design, and cognitive errors. Comment if relevant to the specific evidence book: Is the merging of some risks in the Bioastronautics Roadmap into a single risk appropriate? Is the omission of some risks in the Bioastronautics Roadmap appropriate? These are not relevant to this evidence book.

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89 APPENDIX C Comment on other issues regarding the evidence book, including: • Is the author expertise sufficient? Other disciplines needed? • Literature search: Is the breadth of the search sufficient? Is informa- tion on the search strategy needed? • Overall readability: Is it appropriate for a “science professional” who is not familiar with the specific area covered? See comments above regarding the literature base. The authors seem highly skilled and knowledgeable in a variety of areas, but the draft suggests the need for more input from the clinical, epidemiological, and environmental health sci- entists who are familiar with the occupational and environmental health risks of long-term, low-level exposures to a variety of airborne particulates. Overarching comments on the evidence book: Provide a short paragraph summary of the key issues raised in your review of the paper. No additional comments. Please note: • Crosscutting issues and ideas for broader recommendations • Additional risks that should be added to the list (missing risks) No additional comments.

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