Eye Problems From Space Affect At Least 21 NASA Astronauts: Study

How does microgravity affect your health? One of the chief concerns of NASA astronauts these days is changes to eyesight. Some people come back from long-duration stays in space with what appears to be permanent changes, such as requiring glasses when previously they did not.

And the numbers are interesting. A few months after NASA told Universe Today that 20% of astronauts may face this problem, a new study points out that 21 U.S. astronauts that have flown on the International Space Station for long flights (which tend to be five to six months) face visual problems.

These include “hyperopic shift, scotoma and choroidal folds to cotton wool spots, optic nerve sheath distension, globe flattening and edema of the optic nerve,” states the University of Houston, which is collaborating with NASA on a long-term study of astronauts while they’re in orbit.

The International Space Station as seen by the departing STS-134 crew aboard space shuttle Endeavour in May 2011. Credit: NASA
The International Space Station as seen by the departing STS-134 crew aboard space shuttle Endeavour in May 2011. Credit: NASA

NASA is flying an instrument on board the International Space Station that does optical coherence tomography, which acts like a microscope on the eye. The technology looks at things such as pressure in the eye and changes in the optic nerve and retinal structures.

The collaboration with the University of Houston recently won Heidelberg Engineering’s annual 2014 Xtreme Research Award. In the long term, the researchers involved are hoping to figure out what changes to make for long-duration missions. One example could be changing carbon dioxide levels on the station, if that is found to play a role.

Long-term health considerations will be one thing examined closely when an astronaut and a cosmonaut spend a year on the International Space Station in 2015, with their milestone bringing them in a small group of people who have spent a year or more consecutively in space.

Source: University of Houston

Why Is Balancing So Hard After Spaceflights? Astronaut Posture Could Hold Clues

OTTAWA, CANADA – Astronauts appear to hold their heads more rigidly in relation to their trunks after returning to Earth from multi-month spaceflights, which may affect how they balance themselves back on Earth, according to ongoing research.

A note of caution: the sample size is small (six astronauts so far) and the research is still being conducted by the University of Houston and NASA. So this isn’t finalized in any sense. The early studies, however, shows that people returning to Earth may be changing their “strategy”, said Ph.D. student Stefan Madansingh.

“The changing strategy might put you at higher risks of falls as you ambulate around your environment, and if you are on Mars and you fall and break your hip, that is the start of a very bad day,” he said in a speech.

ESA astronaut Paolo Nespoli works with an experiment on board the International Space Station. Credit: NASA
ESA astronaut Paolo Nespoli works with an experiment on board the International Space Station. Astronauts find it harder to move around on Earth after several months working in the orbiting complex. Credit: NASA

Generally, NASA is interested in learning about changes in cardiovascular, balance and muscle function after six-month spaceflights or more, when they are “like spaghetti people,” Madansingh said. Over the years, astronauts have shown changes in inner eye pressure, bone density, muscles and their balance, among other things.

To obtain the information, NASA has had astronauts walking around a simple obstacle course, which they encourage astronauts to complete at a comfortable walking pace. They’ll weave around pylons, climb ladders and do other simple tasks.

Tests are performed at 180, 60 and 30 days before launch, then one, six and 30 days after landing. (In the shuttle era, astronauts would do these types of tests immediately after landing, but these days there’s a day-long flight from Kazakhstan before arriving in Houston.) Some tests are started from a lying position, and some from a sitting position.

Artist impression of an astronaut on Mars (NASA)
Artist impression of an astronaut on Mars (NASA)

It takes more time for astronauts to complete the obstacle course after coming back from space, Madansingh said, and his ongoing research looks at the relation between the head and trunk as the astronauts are doing so.

As controls, NASA uses bed rest subjects, who are people voluntarily spending 70 days in a head-down position without getting up once, even to go to the bathroom. “I think it’s absolutely bonkers,” Madansingh joked, but added that the bed rest subjects don’t show that same head-trunk changes that returning astronauts do. More research will be needed to learn why, he said.

NASA is putting particular emphasis on these studies as astronauts spend longer times in space. The first one-year International Space Station stay is scheduled for 2015, although some cosmonauts have spent a year or more on the Russian space station Mir.

Madansingh delivered his comments Nov. 15 at the Canadian Space Society annual conference in Ottawa.

New Study Shows Cosmic Rays Could Cause Alzheimer’s

Humans explore Mars in “Distant Shores,” an illustration by NASA artist Pat Rawlins

Cosmic rays from deep space could pose serious health risks to future astronauts on long-duration missions to Mars — even bringing on the memory-destroying symptoms of Alzheimer’s disease, according to the results of a new study from the University of Rochester Medical Center.

While NASA has its sights set on the human exploration of Mars within the next several decades, even with the best propulsion technology currently available such a mission would take about three years. Within that time, crew members would be constantly exposed to large amounts of radiation that we are protected from here by Earth’s magnetic field and atmosphere. Some of this radiation comes in the form of protons from the Sun and can be blocked by adequate spacecraft shielding materials, but a much bigger danger comes from heavy high-energy particles that are constantly whipping across the galaxy, shot out of the hearts of exploding giant stars.

“Because iron particles pack a bigger wallop it is extremely difficult from an engineering perspective to effectively shield against them. One would have to essentially wrap a spacecraft in a six-foot block of lead or concrete.” 

– M. Kerry O’Banion, M.D., Ph.D.

S047While health risks from these high-mass, high-charged (HZE) particles have long been known, the exact nature of the damages they can cause to human physiology is still being researched — even more so now that Mars and asteroid exploration is on NASA’s short list.

Now, a team from the University of Rochester Medical Center (URMC) in New York has announced the results of their research linking high-energy radiation — just like what would be encountered during a trip to Mars — to the degeneration of brain function, and possibly even the onset of Alzheimer’s disease.

“Galactic cosmic radiation poses a significant threat to future astronauts,” said M. Kerry O’Banion, M.D., Ph.D., a professor in the University of Rochester Medical Center (URMC) Department of Neurobiology and Anatomy and the senior author of the study. “The possibility that radiation exposure in space may give rise to health problems such as cancer has long been recognized. However, this study shows for the first time that exposure to radiation levels equivalent to a mission to Mars could produce cognitive problems and speed up changes in the brain that are associated with Alzheimer’s disease.”

In particular the team focused on iron ions, which are blasted into space by supernovae and are massive enough to punch through a spacecraft’s protective shielding.

“Because iron particles pack a bigger wallop it is extremely difficult from an engineering perspective to effectively shield against them,” O’Banion said. “One would have to essentially wrap a spacecraft in a six-foot block of lead or concrete.”

advances-in-treating-alzheimers-afBy exposing lab mice to increasing levels of radiation and measuring their cognitive ability the researchers were able to determine the neurologically destructive nature of high-energy particles, which caused the animals to more readily fail cognitive tasks. In addition the exposed mice developed accumulations of a protein plaque within their brains, beta amyloid, the spread of which is associated with Alzheimer’s disease in humans.

“These findings clearly suggest that exposure to radiation in space has the potential to accelerate the development of Alzheimer’s disease,” said O’Banion. “This is yet another factor that NASA, which is clearly concerned about the health risks to its astronauts, will need to take into account as it plans future missions.”

Read more: Space Travel is Bad For Your Eyes

While Mars explorers could potentially protect themselves from cosmic radiation by setting up bases in caves, empty lava tubes or beneath rocky ledges, which would offer the sort of physical shielding necessary to stop dangerous HZE particles, that would obviously present a new set of challenges to astronauts working in an already alien environment. And there’s always the trip there (and back again) during which time a crew would be very much exposed.

While this won’t — and shouldn’t — prevent a Mars mission from eventually taking place, it does add yet another element of danger that will need to be factored in and either dealt with from both health and engineering standpoints… or accepted as an unavoidable risk by all involved, including the public.

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How much risk will be considered acceptable for the human exploration of Mars — and beyond? (NASA/Pat Rawlings)

Read more on the URMC news page here, and see the full experiment report here.

Illustrations for NASA by Pat Rawlings. See more of Rawling’s artwork here. Inset image: comparison of human brains without and with Alzheimer’s. Source: WHYY.

 

The Moon Is Toxic

As our closest neighbor in space, a time-capsule of planetary evolution and the only world outside of Earth that humans have stepped foot on, the Moon is an obvious and ever-present location for future exploration by humans. The research that can be done on the Moon — as well as from it — will be invaluable to science. But the only times humans have visited the Moon were during quick, dusty  jaunts on its surface, lasting only 2-3 days each before departing. Long-term human exposure to the lunar environment has never been studied in depth, and it’s quite possible that — in addition to the many inherent dangers of living and working in space — the Moon itself may be toxic to humans.

An international team of researchers has attempted to quantify the health dangers of the Moon — or at least its dust-filled regolith. In a paper titled “Toxicity of Lunar Dust” (D. Linnarsson et al.) the health hazards of the Moon’s fine, powdery dust — which plagued Apollo astronauts both in and out of their suits — are investigated in detail (or as best as they can be without actually being on the Moon with the ability to collect pristine samples.)

Within their research the team, which included physiologists, pharmacologists, radiologists and toxicologists from 5 countries, investigated some of the following potential health hazards of lunar dust:

Inhalation. By far the most harmful effects of lunar dust would come from inhalation of the particulates. Even though lunar explorers would be wearing protective gear, suit-bound dust can easily make its way back into living and working areas — as Apollo astronauts quickly discovered. Once inside the lungs the super-fine, sharp-edged lunar dust could cause a slew of health issues, affecting the respiratory and cardiovascular system and causing anything from airway inflammation to increased risks of various cancers. Like pollutants encountered on Earth, such as asbestos and volcanic ash, lunar dust particles are small enough to penetrate deep within lung tissues, and may be made even more dangerous by their long-term exposure to proton and UV radiation. In addition, the research suggests a microgravity environment may only serve to ease the transportation of dust particles throughout the lungs.

Skin Damage. Lunar regolith has been found to be very sharp-edged, mainly because it hasn’t undergone the same kind of erosive processes that soil on Earth has. Lunar soil particles are sometimes even coated in a glassy shell, the result of rock vaporization by meteorite impacts. Even the finer particles of dust — which constitute about 20% of returned lunar soil samples — are rather sharp, and as such pose a risk of skin irritation in instances of exposure. Of particular note by the research team is abrasive damage to the outer layer of skin at sites of “anatomical prominence”, i.e., fingers, knuckles, elbows, knees, etc.

“The dust was so abrasive that it actually wore through three layers of Kevlar-like material on Jack [Schmitt’s] boot.”

– Professor Larry Taylor, Director of the Planetary Geosciences Institute, University of Tennessee (2008)

Eye Damage. Needless to say, if particles can pose abrasive damage to human skin, similar danger to the eyes is also a concern. Whether lunar dust makes its way into the eye via airborne movement (again, much more of a concern in microgravity) or through direct contact from fingers or another dust-coated object, the result is the same: danger of abrasion. Having a scratched cornea is no fun, but if you’re busy working on the Moon at the time it could turn into a real emergency.

While the research behind the paper used data about airborne pollutants known to exist on Earth and simulated lunar dust particles, actual lunar dust is harder to test. The samples returned by the Apollo missions have not been kept in a true lunar-like environment — being removed from exposure to radiation and not stored in a vacuum, for instance — and as such may not accurately exhibit the properties of actual dust as it would be encountered on the Moon. The researchers conclude that only studies conducted on-site will fill the gaps in our knowledge of lunar dust toxicity. Still, the research is a step in the right direction as it looks to ensure a safe environment for future explorers on the Moon, our familiar — yet still alien — satellite world.

Read the team’s paper in full here.

“The Apollo astronauts reported undesirable effects affecting the skin, eyes and airways that could be related to exposure to the dust that had adhered to their space suits during their extravehicular activities and was subsequently brought into their spacecraft.”

– Dag Linnarsson, lead author, Toxicity of Lunar Dust

Top image: Apollo 16 astronaut Charlie Duke with a dust-coated LRV. Side image: a dusty Gene Cernan in the LM at the end of an Apollo 17 EVA. (NASA/JSC)

How Plasma Technology From Space Will Save Our Lives

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It might sound obvious to anyone who’s ever played a video game in the past thirty years, but plasma has been found to be very effective at destroying some truly dangerous beasts. Except in this case, the battlefields aren’t space bases, they’re hospitals… and the creatures aren’t CGI alien monsters, they’re very real — and very dangerous — bacteria right here on Earth.

Scarier than any alien: 20,000x magnification of drug-resistant staphylococcus aureus bacteria (CDC)

Long-running experiments performed aboard the International Space Station have been instrumental in the development of plasma-based tools that can be used to kill bacteria in hospitals — especially potentially deadly strains of Methicillin-resistant staphylococcus aureus, also known as MRSA.

MRSA infections can occur in people who have undergone surgery or other invasive hospital procedures, or have weakened immune systems and are exposed to the bacteria in a hospital or other health care environment. A form of staph that’s become resistant to many antibiotics, MRSA is notoriously difficult to treat, easily transmitted — both in and out of hospitals — and deadly.

Various strains of MRSA infections have been found to be linked to mortality rates ranging from 10% to 50%.

Dr. Gregor Morfill, director of the Max Planck Institute for Extraterrestrial Physics, has been researching the antimicrobial abilities of plasma in experiments running aboard the ISS since 2001. What he and his team have found is that cold plasma can effectively sanitize skin and surfaces, getting into cracks and crevices that soap and even UV light cannot. Even though bacteria like staphylococcus are constantly evolving resistances to medications, they wither under a barrage of plasma.

Eventually, Dr. Morfill’s research, funded by ESA, helped with the creation of a working prototype that could be used in hospitals — literally a plasma weapon for fighting microbes.

It's no BFG, but it can kill flesh-eating monsters in mass quantities (Photo: Max-Planck Institute for Extraterrestrial Physics)

This is yet another example of “trickle-down” technology developed in space. Over two dozen astronauts and cosmonauts have worked on the research aboard the ISS over the past decade, and one day you may have cold plasma disinfecting devices in your home, cleaning your toothbrushes and countertops.

In addition the technology could be used to clean exploration spacecraft, preventing contamination of other worlds with Earthly organisms.

“It has many practical applications, from hand hygiene to food hygiene, disinfection of medical instruments, personal hygiene, even dentistry,” said Dr. Morfill. “This could be used in many, many fields.”

Bacteria, prepare to get fragged.

News source: ScienceDaily. Top Doom3 image from http://www.moddb.com/.

Yum! Dirty fingers! (MPE)

Space Travel Is Bad For Your Eyes

Microgravity — or “zero-g” as it’s sometimes called — is not a natural state for the human body to live in for prolonged periods of time. But that is what today’s astronauts are often expected to do, whether while on expedition aboard Space Station or during a future voyage to the Moon or Mars. A host of physical issues can result from the space environment, from bone loss and muscle atrophy to the risks associated from increased exposure to radiation.

Now, there’s another downside to long-term life in orbit: eye and brain damage.

A team of radiologists led by Dr. Larry A. Kramer from The University of Texas Medical School at Houston performed MRIs on 27 astronauts, measuring in each the shape and thickness of the rear of the eyes, optic nerve, optic nerve sheath and pituitary gland.

In 7 of the 27 astronauts flattening of the backs of the eyes was noted, and enlargement of the optic nerve was detected in nearly all of them — 26 out of 27.

In addition, four exhibited deformation of the pituitary gland.

The optic nerve. (NIH)

The changes to the eyes and optic nerves are similar to what are typically seen in those suffering from idiopathic intracranial hypertension (IIH), a disorder characterized by increased pressure within the skull. Symptoms typically include headache, dizziness and nausea, and if left untreated it can produce permanent vision loss through optic nerve damage.

“The MRI findings revealed various combinations of abnormalities following both short- and long-term cumulative exposure to microgravity also seen with idiopathic intracranial hypertension,” said Dr. Kramer. “Microgravity-induced intracranial hypertension represents a hypothetical risk factor and a potential limitation to long-duration space travel.”

Chief of flight medicine at NASA’s Johnson Space Center, Dr. William J. Tarver, noted that although no astronaut has been kept from flight duties as a result of such risks, NASA will continue to “closely monitor the situation” and has placed the potential danger “high on its list of human risks.”

The team’s paper was accepted into the journal Radiology on Feb. 1.

“Orbital and Intracranial Effects of Microgravity: Findings at 3-T MR Imaging.” Collaborating with Dr. Kramer were Ashot Sargsyan, M.D., Khader M. Hasan, Ph.D., James D. Polk, D.O., and Douglas R. Hamilton, M.D., Ph.D.

Update Oct. 24, 2013: Further investigation by researchers at Houston Methodist and Johnson Space Center have shown more evidence of long-term eye damage after just two weeks in orbit. Read more.