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Every banana is slightly radioactive.

Bananas are rich in potassium, and about 0.012 % of it is the radioactive isotope potassium-40. One banana delivers roughly 0.1 microsievert of radiation dose. A person's natural annual dose is around 2 to 3 millisieverts, the equivalent of about 25,000 bananas. Your body keeps its potassium level constant, so extra bananas don't raise your exposure over time.

Useful: The banana equivalent dose is a handy yardstick for putting tiny radiation numbers in the news into perspective.

Source: en.wikipedia.org

AlltagPhysikRadioaktivitaet

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Why are bananas slightly radioactive?

  1. Because of pesticides
  2. Because of the isotope potassium-40
  3. Because of carbon-14 in the peel
  4. They aren't
Show the answer

Correct: Because of the isotope potassium-40

A tiny fraction of natural potassium is the radioactive potassium-40.

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