Study says space radiation less of a risk

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.

NASA study says deep space will cause cancer and destroy stomachs

We’re all gonna die! A NASA study on rats using simulated space radiation suggests that long duration space missions beyond Earth orbit will cause cancer as well as significant harm to human intestines.

The study, published by cancer researchers at Georgetown University Medical Center, used mice to test exposure to heavy ion radiation, which mimics the galactic cosmic radiation found in deep space. If that sounds complicated, essentially researchers compared “space” radiation to X-ray radiation and found its effects to be much more dangerous.

After long exposures to a low dose of galactic radiation, mice had permanent damage to their gastrointestinal tracts and could no longer absorb nutrients in food. The mice also developed cancerous growths in their intestines — raising concerns that astronauts who venture far into space would face the same deadly health issues. “While short trips, like the times astronauts traveled to the moon, may not expose them to this level of damage, the real concern is lasting injury from a long trip,” said Kamal Datta, head of Georgetown’s NASA Specialized Center of Research, in a press release.

More here.

Must I point out the uncertainties and weaknesses of this study? They did the test on rats. They simulated the radiation. And it appears they simulated the radiation dosages assuming the spacecraft would have little or no shielding, an absurd approach.

Space is dangerous, but there is no reason to exaggerate the dangers wildly, unless you wish to generate fake reasons for additional funding, as NASA is prone to do.