Study says space radiation less of a risk

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A newly released study now claims that, based on a long term review of astronauts who have spent a considerable time in space, it appears that space radiation does not cause an increase in cancer later in life.

The new study analyzed information from 418 space travelers, including 301 NASA astronauts who had traveled to space at least once since 1959, and 117 Russian or Soviet cosmonauts who had traveled to space at least once since 1961. These participants were followed for about 25 years, on average.

During this time, 89 of the participants died. Among the 53 NASA astronauts who died, 30% died from cancer and 15% from heart disease; while among the 36 Russian or Soviet cosmonauts who died, 50% died from heart disease and 28% from cancer.

The researchers used a special statistical technique to determine whether deaths from cancer and heart disease likely had a common cause — in this case, the common cause would be space radiation. But their results did not point to a common cause of death. “If ionizing radiation is impacting the risk of death due to cancer and cardiovascular disease, the effect is not dramatic,” the authors wrote in their study, published July 4 in the journal Scientific Reports.

This story first appeared about two weeks ago, but I didn’t think it significant, and still don’t. The sample is just not large enough to draw any solid conclusions. Moreover, this is exposure in low Earth orbit, not on interplanetary missions where the radiation risk is higher. It would be a big mistake for future space engineering to accept these findings blindly.

Still, news reports keep popping up about it, and I decided I should at least note it here on Behind the Black.


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  • Phill O

    Trying to relate to the general population would be difficult since the people were chosen for exemplary physical attributes. Where could one fine a reasonable control group? This is probably why only space travelers were included in the data set. It would be interesting to see a comparison to a similar group who did not “fly”.

  • pzatchok

    Cancer and heart disease don’t care if your were an astronaut. And over half of the people sampled were never pilots of fighter aircraft. Plus after 40 unless you really work at it you loose muscle mass and develop heart disease just like everyone else.
    They are not special.

    And their rates of heart disease and cancer are not significantly different than their general populations numbers.

    What this study really helps are the plans for private space tourists. Proof that a week in low orbit space will not increase their risk of death. Plus no reason to increase their personal health insurance premiums.

  • fred

    I agree with you (and the study) that the number of data points is too low provide overwhelming evidence.

    However, In the spirit of Rand’s “Safe is not an option” I think that results show that the increased cancer risk from relatively short space flights is negligible. By negligible, I mean close enough to the non-astronaut population ….

    A reasonable person would be making spaceflight decisions based upon the much, much more significant risk of being accidentally blown up, or depressurized, etc.

  • Edward

    Perhaps Rand got his idea from Bill Whittle: (7 minutes)

    Or maybe it was the other way around:
    My friend and noted space expert Rand Simberg summed it up perfectly when he said that we’ll know we’re serious about space travel when we have entire cemeteries full of dead astronauts who lost their lives showing us how to do it right, just like Gann’s generation did, because that’s the deal. That’s what it costs.”

    You see, either you live for something, something worth dying for, or you just rot on the installment plan. That’s the Deal.

    But we lost the stomach for it because we didn’t go anywhere or do anything new. Part of the deal, you see, is that you pay in blood for progress. If there’s no progress, what’s the point?

    Someone has to take some risks in order to show us how to do it right. Otherwise we will make no progress and go nowhere.

    In the meantime, if — IF — radiation in low Earth orbit is not as dangerous as we had feared, then we have learned something, including something about how to do it right.

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