The future of long term space missions may be in jeopardy. A new study undertaken by a team of scientists at the Johnson Space Center in Houston, Texas has revealed the efficacy of pharmaceutical drugs tends to diminish rapidly in space.
A science information adviser at the Royal Pharmaceutical Society, Dr. Colin Cable, told the BBC that “On Earth, medicines are tested to assess the effects of, for example, temperature, moisture, oxygen and light, and are packaged and stored to ensure they remain stable and effective over their shelf life.
“Repackaging of medicines into containers that do not give the medicines the protection required to moisture, oxygen and light can have a detrimental effect on their stability.”
Whether exposure to cosmic radiation plays a role is not known, but Cable believes it might as radiation does affect medicine adversely.
Lower potency after space storage
The research team’s study bluntly states that “A number of formulations tested had a lower potency after storage in space.”
The team arranged an experiment to be conducted on the orbiting International Space Station (ISS). Transporting 35 separate drugs in four boxes to the station, they were stored for various times aboard the craft. According to the study, one remained aboard the space station just under two weeks while another stayed on board for a 28-month duration.
Concurrently, for identical boxes containing exactly the same drugs with the same strengths and dosages were kept in storage at the Johnson facility.
Upon comparison of the Earth-bound control group and the ones that spent time in space, the study revealed that “A number of formulations tested had a lower potency after storage in space with consistently higher numbers of formulations failing United States Pharmacopeia potency requirement after each storage period interval in space than on Earth.
“This reduction in potency of flight samples occurred sooner than the labelled expiration date for many formulations suggesting that storage conditions unique to the spacecraft environment may influence stability of pharmaceuticals in space.”
Various conditions were monitored including the microgravity present in orbit, exposure to radiation, vibrations during the launch into space and re-entry into the atmosphere, the increased carbon dioxide levels in the ISS and subtle differences in temperature and humidity.
All those factors were measured to determine if any played a significant role in reducing the drugs’ potency.
Not all conditions detrimental
Cable added that not all conditions in space may be detrimental to medicines. “One potential benefit of keeping medicines in a space station is that the medicines will be exposed to a carbon dioxide-rich environment, this may help minimize the degradation of those medicines prone to oxidation, such as adrenaline, vitamin C and vitamin A.”
The study concludes: “Characterization of degradation profiles of unstable formulations and identification of chemical attributes of stability in space analog environments on Earth will facilitate development of space-hardy medications.”
Some theorize that radiation may have had little impact upon the efficacy of the medicine over the long term and that a microgravity environment may have affected the actual molecular bonding of the various serums, antibiotics and other medicines.
If that is the case, longer range space craft need only to incorporate an area of the ship that has artificial gravity to protect the strength of drugs. That can be accomplished by rotation creating centrifugal force.