A study that kept astronauts’ blood for 20 years and looked at cancer risk found that changes to astronauts’ blood need to be closely monitored.
DNA Mutations were found, but not at significantly high levels
The study published in Nature Communications Biology found that the astronauts had a lot of DNA mutations, but it’s still below a level of concern.

The researchers found that the astronaut’s blood was not all that interesting. Instead, they said astronauts should have blood tests every so often to check for possible changes. They think that it should be looked at in the bigger picture. For example, a 2019 study reported in livescience.com found that astronauts are not getting cancer from ionizing radiation in space.
Studying health risks to astronauts because of growing interest in commercial space flights
The team decided to do the new study because “there is a growing interest in both commercial spaceflights and deep space exploration,” Dr. David Goukassian, the study’s lead author and a professor of cardiology at Icahn Mount Sinai, said in a statement.
In recent moves to bring equality, NASA changed its rules about how much radiation astronauts can be exposed to over their lifetimes. On 24th June 2021, it was reported by the US National Academies of Sciences, Engineering, and Medicine that NASA was encouraged to proceed with its plans to adopt a new standard that limits all astronauts to 600 millisieverts of radiation over their career. Before, women astronauts had lower limits than men. Now women’s radiation limits will be increased to align with men’s. Space.com notes that the population of NASA has not been shown to include people of other genders.
Researchers found more somatic mutations in the genes of the 14 astronauts studied than in the general population of people who have been to space.

Between 1998 and 2001, the space cohort flew, on average 12-day shuttle missions. About 85% of the astronauts were men, and six were on their first mission.
Blood mutations might occur, making astronauts more susceptible to heart disease and some types of cancer
The researchers obtained blood samples from the astronauts and stored them in a freezer after taking the blood samples. They looked at the samples after 20 years and found that the number of somatic mutations in the genes was less than 2%. This was discovered after looking at the samples. A mutation that occurs in the DNA sequence of a cell that is not a gamete, germ cell, or gametocyte is referred to as a somatic mutation. According to the statement, people over the specified limit have an increased risk of developing cardiovascular disease and certain types of cancer.

“The presence of these mutations doesn’t necessarily mean that the astronauts will get heart disease or cancer, but there is a chance that this could happen over time if they are exposed to the harsh environment of deep space for a long time,” said Goukassian.
Recommendations of the study
According to the findings of the latest study, it is recommended that astronauts get regular blood tests to monitor their bodies for any potential changes due to mutations.
Both the recent study and the previous study from 2019 focused their attention primarily on astronauts who were serving on short-term average 12-day shuttle missions. It is important to note by comparison that the Artemis mission has an estimated mission length of 42 days, and it will take astronauts about nine months to travel to Mars.
We can only hope that the recommendations will assist in maintaining the health of any future astronauts as space agencies work on more ambitious missions, such as moon bases and mars colonization.
Featured image credit: Tracy Caldwell Dyson in Cupola ISS by NASA