If the expectant mother is exposed to a significant amount of radiation, which risks in children have studies shown to increase?

• A. Leukemia
• B. Cancers
• C. None
• D. Both leukemia and cancers

Answer: (D)

Radiation can damage DNA in developing fetal cells, and that damage can lead to cancer later on. When a fetus is exposed to significant ionizing radiation, the risk of leukemia in children rises because blood-forming cells are highly susceptible to mutagenesis during development. At the same time, radiation can initiate other types of cancer in childhood, as other developing tissues may accumulate mutations that later manifest as solid tumors. Studies show a dose-response relationship: higher exposure increases the likelihood of cancer, with leukemia often presenting earlier in life and other cancers potentially appearing later. So, the observed increased risks include both leukemia and other cancers.