While the term "radiation" is quite generic, encompassing such phenomena as radio waves and visible light in addition to damaging rays, high-energy radiation has the potential to cause significant biological harm. In particular, ionizing radiation—waves of sufficient energy to cause bonds in biological molecules to break—leads to structural and genetic damage to cells. This can result in mutations, cancers and cell death. Because rapidly dividing cells are more susceptible to ionizing radiation than less active cells, developing babies are at particular risk for radiation damage.
Delayed Growth and Development
Jefferson Lab, which publishes a list of possible effects of radiation on developing embryos, notes that prenatal radiation exposure can result in delayed growth or development. This is because ionizing radiation has the potential to kill cells, meaning that the baby has to produce many more cells to reach a particular level of growth or development.
Developmental Abnormalities
The U.S. Nuclear Regulatory Committee, or NRC, publishes a manual on the biological effects of radiation that includes possible consequences to an unborn baby. Among the possible effects they include developmental abnormalities or failure of the organs to form and function normally. In particular, embryos—babies of less than eight weeks gestational age—are susceptible to organ damage because it is during the embryonic period that organs form and begin to function. Cellular damage sustained during this period can be particularly detrimental to normal development.
Death
If radiation exposure occurs in a single high dose, or if exposure is repeated over a period of time and accumulates to high levels, unborn babies may not survive the exposure, notes the U.S. Centers for Disease Control and Prevention, or CDC. High doses of radiation before implantation will cause a zygote to fail to implant, whereas radiation exposure during embryonic or fetal periods can cause such severe developmental and chromosomal abnormalities that the developing baby is spontaneously aborted.
Cancer
Provided that high doses of radiation don’t result in miscarriage, the CDC notes that they increase the probability of neonatal death or cancers during childhood. Cancer is the result of damage to a cell’s genetic material. If the cell then divides, it spreads its erroneous genetic material to both daughter cells, which later divide, further replicating the genetic errors. Eventually, a large ball of cells with errors in their genetic information develops, and often these errors cause unrestrained cellular division and growth, which can lead to tumor development. Cancerous cells can then break off of the tumor and spread throughout the body, settling in other organs and stealing nutrition from normal cells.
References
- Jefferson Lab: Radiation Effects
- "Reactor Concepts Manual"; Biological Effects of Radiation; U.S. Nuclear Regulatory Committee
- Centers for Disease Control: Radiation Effects
