LANCASTER, Calif. — Doctors and astronauts told a House panel June 15 that they support proposals that would authorize NASA to provide improved health care for former astronauts.

Witnesses told the House Science Committee’s space subcommittee that giving NASA more responsibility for the health care of former astronauts would both ensure those people receive better treatment for the long-term effects of spaceflight as well as expand the agency’s knowledge about those effects.

“The question should not be whether we provide these services to our astronauts, but rather how to do it in a way that best addresses the current and future needs of our space explorers,” said Rep. Lamar Smith (R-Texas), chairman of the full committee.

Proposals under consideration by the committee would have NASA provide health care directly to former astronauts for their rest of their lives. Currently, NASA provides optional annual health screenings for former astronauts, but any additional treatment is handled through programs administered by the Department of Labor and Department of Veteran Affairs.

Richard Williams, the chief health and medical officer at NASA, said there two problems with this approach. One is that doctors outside the agency often don’t understand the health risks associated with long-duration spaceflight. “An average doctor or nurse practitioner, no matter how skilled they are, has no exposure to or understanding of these issues,” he said.

Another issue, he said, is the limited data available on the effects of spaceflight. About 280 former astronauts are alive today, a small sample size by the standards of traditional clinical studies. Moreover, only about 60 percent of them participate in NASA’s existing screening program. “Expanding our authority to provide for extensive testing would be a great incentive to increase this number,” he said.

“Every additional astronaut who can be a part of this population is vital,” said Chris Cassidy, chief of the NASA astronaut office.

Michael Lopez-Alegria, a former astronaut who is president of Association of Space Explorers-USA, noted that many former astronauts drop out of the current screening program because of the limited benefits it offers. That’s especially true, he added, for those who don’t live near the Johnson Space Center, where the screenings take place.

“A relatively routine physical that lacks targeted surveillance of known space-related health hazards, let alone any kind of in-depth diagnosis or provision of treatment, is simply not compelling enough for many former astronauts who might live far from Houston to take time from work and family to make the trip,” he said. His association’s members, he said, unanimously support enhanced medical treatment for former astronauts.

Those health risks, and the lack of data, are of particular concern for long-duration missions where extended exposure to radiation and weightlessness may prove to be particularly hazardous. Former astronaut Scott Kelly, who returned to Earth earlier this year after spending nearly one year on the International Space Station, said he noticed the difference between that mission and an earlier half-year stay on the station. That included conditions ranging from rashes to flu-like symptoms he said he suffered in the weeks after landing in March.

“Exposure to the space environment has permanent effects we simply do not fully understand,” he said. The current monitoring system, he argued, “is too limited to provide the data needed to ensure the safety of our space explorers.”

Both Republican and Democratic members of the committee appeared to support giving NASA the authority to provide additional healthcare and monitoring services. One issue raised by some members, including space subcommittee chairman Rep. Brian Babin (R-Texas), was the additional cost of that monitoring, citing one study that estimated annual healthcare costs for astronauts and their families could be as high as $6.5 million.

Williams said NASA concluded that expanding the screening program would roughly double its cost to $800,000 a year. He didn’t identify the cost of the additional healthcare, but noted astronauts tended to be healthier than the general population. He estimated there would be one or two cases of “significant illness” each year among former astronauts, like cancer, that would cost up to $500,000 each.

Jeffrey Kahn, a bioethicist, argued that NASA had a responsibility to take care of the health of astronauts. “Employers who knowingly expose employees to risk have an ethical responsibility to provide protection to the extent possible and to address the harms that occur when protections fail or turn out to be inadequate,” he said.

Collecting additional data about health risks from long-duration spaceflight is critical, Williams said, “if we’re serious about going anywhere beyond low Earth orbit.”