The People for the Ethical Treatment of Animals has obtained documents discussing a controversial NASA-funded project that would expose squirrel monkeys to radiation.
Citing an exemption under the federal law, the U.S. Department of Energy redacted essentially all of the content of the emails and the draft decision it forwarded to PETA.
A statement on PETA's website read: "Unfortunately, before the government sent us these documents, it blacked out Brookhaven's decision, so we don't know if plans to hurt these animals are moving forward or not."
A decision is pending, a spokesman for Brookhaven National Laboratory told SPACE.com. The time frame was not available.
New NASA radiation experiments
The proposed project would expose 27 squirrel monkeys to high-energy gamma-ray radiation, then researchers would observe its effects on the monkeys' health and task performance.
The objective would be to help NASA predict the neurobehavioral effects of space radiation — the most poorly understood health risks for astronauts, NASA officials have said.
In November 2009, when plans for the study were first announced, NASA officials told SPACE.com that research that simulated the effects of space radiation showed that it affected nerve cells in cultures, and could affect behavior in mice and rats. But those studies were limited by the amount of extrapolation required for human behavior and performance.
"Studies in nonhuman primates are essential to be able to best predict neurobehavioral effects of radiation on humans," NASA spokesperson Bill Jeffs of the Johnson Space Center in Houston said at the time.
The study would reportedly expose the monkeys to radiation similar to what astronauts would experience on a three-year voyage.
Over the past year, animal rights advocates have protested the plans.
As part of a letter-writing campaign to thwart the experiment, PETA describes it as not only cruel but also attacks the design of the experiment, saying the differences between the monkeys and humans will make it impossible to generate usable data, and that the single large dose of radiation will not simulate astronauts' extended exposure.
Russian project draws protests
NASA isn't the only space agency looking to use monkeys to advance spaceflight by exposing them to radiation. And PETA is not the only animal rights group filing protests.
The advocacy group Animal Defenders International is rallying against a Russian Federal Space Agency (Roscosmos) project called Mars500. Like the proposed NASA project, this study uses monkeys as proxies for humans exposed to radiation during extended space travel, ADI officials said.
ADI officials say the Russian tests severely restrain the monkeys and cause horrific side effects.
Officials from the European Space Agency have reportedly said they view using monkeys to simulate space travel as unnecessary, ADI officials added.
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