What dose of radiation is associated with Permanent Sterility?

Permanent sterility is associated with a specific dose of radiation exposure, which is generally estimated at around 500 rems (or 5,000 mSv for clarity in SI units). This level of radiation exposure results in significant damage to the reproductive cells, specifically affecting the ovaries in females and the testes in males. At this dose, the radiation effect is so profound that it disrupts the ability of the reproductive organs to produce viable gametes, leading to a state of irreversible sterility.

It's important to understand that varying doses of radiation have different biological effects, particularly on reproductive tissue. Lower doses may cause temporary infertility or subfertility rather than permanent effects. The threshold for permanent sterility is established through extensive studies on human and animal models, providing a clear understanding of the impacts of radiation on fertility.

In this context, the other options either fall below or exceed the necessary dose for permanent sterility, thus reinforcing the significance of the 500 rems threshold.