Outside of the Earth's protective magnetosphere, astronauts are at risk from exposure to radiation from solar particle events and high-energy galactic cosmic rays. Cell and tissue damage caused by exposure to these types of radiation are distinct from that caused by terrestrial radiation sources such as x-rays, and the biological consequences are poorly understood.
Current work is focused on developing the knowledge base and tools required for accurate assessment of health risks resulting from space radiation exposure including cancer and circulatory and central nervous system diseases, as well as acute risks from solar particle events. USRA's Division of Space Life Sciences Space Radiation Team scientists work at multiple levels to advance this goal with major projects in biological risk research, epidemiology, physical, biophysical, and biological modeling.
The risk of radiation carcinogenesis for epithelial cancers of the lung, breast, esophagus, stomach, colon, and bladder is particularly high. To better understand the molecular mechanisms of space radiation-induced initiation and progression of epithelial cell carcinomas, USRA scientists in the Space Radiation Laboratory use both 2D and 3D esophageal tissue analogs in culture. Three-dimensional organotypic cell culture (a form of tissue engineering) provides a realistic model that mimics the structure and growth characteristics of fully differentiated human tissue. Their ongoing work with these model systems will provide insight into the mechanisms by which radiation drives cancerous changes in cells, thereby allowing for more accurate cancer risk assessment in astronauts.