Abstract Radiation induced injury is a limiting factor in radiation related approaches from earth
to space. Inductions of a wide spectrum of damages in radiotherapy patients due to unwanted normal
tissues irradiation and space radiation related diseases in astronauts have been caused many
limitations in cancer treatment and space missions. There are many radiation protection/mitigation
approaches including: physical, chemical, biological and physiological methods. Radiation protection
using these methods is expensive and also has many problems including acute toxicities and
difficulties in their targeting to normal tissues. Based on experimental and hypothetical data, showing
that medical/biological gases have many protective effects such as antioxidant, anti-inflammatory,
anti-apoptotic, and induction of radioresistance, we hypothesize that similar gases which have
been produced by microorganisms (biogases) have those properties and may be used as radiation
mitigators/protectors in radiation related approaches such as radiotherapy, radiation accidents
and in space missions. Isolation microorganism in safe laboratory conditions in enough amounts,
finding non-toxic dose of microorganisms that provide highest radioprotection percent, dose reduction
factor (DRF) calculation to compare the radioprotective efficacy of the microorganisms, finding
the best targeting techniques to deliver those microorganisms into normal tissues, genetically
manipulations of microorganism to achieve the highest amount of biogases with lowest side effects
can be done for testing the hypothesis.
ª 2015 Tehran University of Medical Sciences. Published by Elsevier Ltd. This is an open access articl