Who is required to undergo a thyroid bioassay?

The correct answer is based on specific regulatory guidelines and safety protocols associated with handling radioiodine, a radioactive isotope commonly used in various medical and research applications. Individuals handling more than 1.0 mCi of radioiodine are required to undergo a thyroid bioassay to monitor potential exposure and ensure that any uptake of radioactive materials is detected early.

Thyroid bioassays are a vital safety measure because the thyroid gland has a high affinity for iodine, and any accumulation of radioiodine can pose significant health risks, including an increased likelihood of thyroid cancer or other health complications associated with radiation exposure. By conducting a bioassay, personnel can ensure safety compliance and evaluate the extent of any exposure.

In contrast, the other choices are not applicable because they do not represent the threshold or conditions that necessitate a bioassay. For instance, individuals handling sealed radioactive materials or those only dealing with smaller quantities of radioiodine, such as less than 1.0 mCi, typically do not require the same level of monitoring, as the risk of significant uptake is lower. Additionally, while all personnel working in radiation safety must be trained and follow safety protocols, not everyone necessarily needs to undergo a thyroid bioassay unless they meet the