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NASA pretending that space radiation is sort of OK for women, but it’s not

New NASA radiation standards for astronauts seen as leveling field for women, Science, By Anil OzaJun. 29, 2021 

A blue-ribbon panel has endorsed NASA’s plans to revise its standard for exposing astronauts to radiation in a way that would allow women to spend more time in space.

A report by the U.S. National Academies of Sciences, Engineering, and Medicine released on 24 June encourages NASA to proceed with its plans to adopt a new standard that limits all astronauts to 600 millisieverts of radiation over their career. The current limit is the amount of radiation that correlates with a 3% increase in the risk of dying from a cancer caused by radiation exposure—a standard that favored men and older astronauts whose cancer risk from radiation was lower. The proposed standard would limit all astronauts to the allowable dosage for a 35-year-old woman.

The changes are in line with current data and puts women on an equal footing, says Hedvig Hricak, a radiologist at Memorial Sloan Kettering Cancer Center and chair of the committee that wrote the report. “There’s no evidence for significant gender difference in the radiation exposure, and associated risk of cancer,” she says.

The new standard comes as NASA gears up for renewed exploration of the Moon and, eventually, a mission to Mars. The change should remove gender from the list of factors used to decide who gets chosen for those missions, says Paul Locke, an environmental health expert at Johns Hopkins University who was not on the committee. “Women will not be penalized because they are, under the old model, at higher risk,” he says.

Whereas some experts lauded NASA’s intentions, others worry the proposal ignores the complexities and uncertainties of deep space travel. “I think they’ve pulled together the best data they have. But again, I think, more research is going to be needed,” says Albert Fornace, a radiobiologist at Georgetown University. With so few people having traveled beyond low-Earth orbit, most of the data for setting radiation exposure limits in space come from survivors of the atomic bombs in Japan and studies of people, like uranium miners, who work in conditions with high exposure to radiation. The long lead time for voyages to Mars also gives scientists time to develop ways to shield astronauts from higher levels of radiation, Fornace adds.

Francis Cucinotta, a biophysicist at the University of Nevada, Las Vegas, doesn’t agree with the report’s backing of a single dosage level. Instead, the former chief scientist for NASA’s radiation program thinks equity should come in the form of equal risk rather than equal dosages of radiation.

“[It] sounds like they’re just going to ignore the science and try to make it comfortable for everybody,” Cucinotta says, arguing that age, sex, and race affect an individual’s risk of developing cancer and should be factors when determining the amount of time astronauts can spend in space. “When they’re selected to be astronauts, there’s a lot of things where it’s not equal—it’s based on performance capability. But they’re not applying that model here.”

Cucinotta would stick with the 3% increase in the risk of dying of cancer. For a Mars mission, which is expected to expose astronauts to 1000 millisieverts, he proposes raising that maximum risk to 5% after conducting research on countermeasures and weighing genetic markers that lower an astronaut’s risk of developing cancer………..    https://www.sciencemag.org/news/2021/06/new-nasa-radiation-standards-astronauts-seen-leveling-field-women

July 1, 2021 - Posted by Christina Macpherson | space travel, women