Which substance is a major source of contamination during I-131 therapy?

Saliva is considered a major source of contamination during I-131 therapy primarily because iodine-131 (I-131) can be excreted in salivary glands and subsequently secreted into saliva. Patients receiving I-131 treatment, often for thyroid conditions, may experience increased levels of radioactive material in their saliva, which can lead to contamination of surfaces and individuals around them. This contamination risk emphasizes the importance of proper hygiene precautions and restricted interactions after administration of I-131, especially in the initial days following the therapy when the radioactive dose is highest.

In terms of risk management, understanding that saliva can carry radioactivity helps healthcare professionals implement strategies to minimize exposure to others, particularly vulnerable populations. While blood, skin cells, and hair can also potentially carry radioactivity, they are less significant compared to the volume of saliva produced and the nature of its contact during daily activities.