NRC Lukewarm About NASA's Proposed Space Radiation Cancer Risk Model

The National Research Council (NRC) issued a report today evaluating changes NASA is proposing to make on how it estimates the risk that astronauts could develop cancer because of exposure to radiation in space.   The report concluded that the proposed changes are better than the current model NASA is using, but still needs improvements.

The study committee, chaired by R. Julian Preston of the Environmental Protection Agency, assessed changes NASA is proposing to its current model for estimating the risk of radiation-induced cancer in astronauts.   The existing model was most recently updated in 2005.  Last year NASA proposed changes based on new findings from a number of sources. 

Overall, the NRC committee concluded that the proposed changes represent the state-of-the-art, but  “There remains a need for additional data to be developed to enhance the current approach and to reduce uncertainty in the model.”

The committee complained that “NASA’s proposed model and associated uncertainties are complex” and “require a very clear and precise set of descriptions,” that were not provided in NASA’s published report.  Thus, the committee found it difficult to review, and while it asked NASA for clarifications throughout its deliberations, not all of the ambiguities were resolved.

“The overall evaluation of the committee is that NASA’s proposed model represents a definite improvement over the previous one. However, the committee urges that the necessary improvements identified by the specific recommendations provided [herein] be incorporated before the proposed integrated model is implemented.”