Lost in space: Checking up on the health of astronauts

Astronauts heading to space undergo a series of physical and mental preparations to ensure they can withstand the pressures that come with the job. But did you know that they also get a radiation checkup?

Since 2007, Health Canada researchers have examined the blood of astronauts before and after their space missions to understand the impact of radiation on their bodies. Dr. Lindsay Beaton is part of the team responsible for this interesting work.

“Working with the Canadian Space Agency, we get a blood sample before the astronaut goes into space and build an individualized model,” says Dr. Beaton. This model is a blueprint of the astronaut’s DNA and can help predict how their body will react to radiation.

“Once they come back from their 6-month stay on the International Space Station, we test their blood again to determine the actual impact of radiation.”

Space radiation

While they are in space, astronauts are exposed to ionizing radiation, which is a type of radiation that can cause cell damage if proper measures are not taken to protect against it. This is the same type of radiation used for medical imaging, such as X-rays and CT scans.

Since astronauts get a constant low-level of exposure to radiation while they are in space, they might be at a slightly increased risk of developing health issues. “It will be interesting to know if the cell damage is different the longer someone stays in space; for example when astronauts go to Mars for a three year mission,” says Dr. Beaton.

The science of radiation health

While on a mission, astronauts must wear badges called dosimeters to measure the amount of radiation to which they are exposed. Dr. Beaton and her team are responsible for performing the biodosimetry of astronauts themselves. “This means that we are assessing their exposure to radiation by examining a biological sample, blood in our case.”

Dr. Beaton and her team look at the white blood cells, which contain the astronaut’s DNA, and they examine the very distinct characteristics of each chromosome to find any existing anomalies or defining characteristics.

The ionizing radiation in space causes the DNA strands to break and it’s possible to see very distinctive types of damage. Once the astronauts are back on earth, scientists look at the difference between their initial blood sample and the new one to understand what damage has been caused. They also take an additional sample 6 months after their return to earth to see if the cells were able to repair themselves.

“The effects are based on the amount of radiation the astronaut received, the rate at which the radiation is received, the amount of oxygen in the environment, and their individual sensitivity to radiation,” says Dr. Beaton. “Through biodosimetry, we are trying to capture this sensitivity as well as the astronaut’s biological response to stress.”

What’s next?

Biodosimetry has been completed for 10 astronauts to date, and the results show that the radiation exposure the astronauts receive isn’t a significant health concern.

Dr. Beaton and her team continue to work with the Canadian Space Agency, NASA and the European Space Agency to increase their knowledge of the effects space radiation can have on humans.

The work that Dr. Beaton and her team are doing could also be used in other events, for example, in the unlikely event of an emergency at a nuclear power plant. In that case, they would have the skills required to examine any effect the radiation could have on anyone impacted by the emergency. “We hope this never happens, but our work with astronauts helps us maintain our skills for emergency situations.”

Dr. Lindsay Beaton is a shining example of a passionate scientist who enjoys her work and is making a difference in her field.

 

Let’s draw attention to the incredible work of women in science! This article is part of a month-long series celebrating women in science, from International Day of Women and Girls in Science (February 11) to International Women’s Day (March 8).