Lesson: Nuclear Radiation in Medicine

Polonium-210 is a radioactive isotope of polonium with a half-life of 138 days. It decays via alpha decay to lead. Which of the following are reasons why polonium-210 cannot be used as a radioactive tracer?

1. Polonium-210 is too expensive to be used as a radioactive tracer.
2. Polonium-210 decays too slowly and thus would remain in a person’s system for too long.
3. Polonium-210 is a very rare isotope, and thus refining it for use in medicine is too difficult.
4. Polonium-210 decays too quickly and thus would not remain in a person’s system long enough to be useful.
5. Polonium-210 decays to lead, which is highly toxic.
6. Polonium-210 decays via alpha decay. Radioactive tracers have to emit gamma rays. The alpha particles released by polonium would be absorbed by the body’s cells.

Which of the following correctly explains why gamma radiation is used for radiation beam therapy rather than alpha or beta particles?

Which of the following is the correct unit for ionizing radiation dose?