At which of the following doses do deterministic effects typically become observable?

Deterministic effects, also known as non-stochastic effects, are directly related to the dose of radiation received; they have a threshold below which they do not occur. These effects include phenomena such as skin burns, radiation sickness, or damage to organs, and they typically manifest after a specific amount of radiation exposure.

In radiation biology, it is generally accepted that these observable effects often start to occur at doses above 1000 milligray (mGy). This threshold is significant because at or above this level, the severity and occurrence of effects become more predictable and can be correlated with dose increases.

While doses lower than 1000 mGy may lead to various biological changes at the cellular level, the observable, clinically significant endpoints do not usually manifest until the dose reaches around 1000 mGy. At higher doses, such as 2000 mGy or 3000 mGy, the severity and likelihood of deterministic effects would increase considerably, but the first signs of these effects are typically associated with the 1000 mGy level.