Bioassays: Internal Exposure Monitoring

Bioassays are performed on persons who use unsealed quantities of radioactive materials to determine whether any activity has entered the body. The results are used to:

1. Estimate internal organ doses.

2. Determine the presence of airborne radioactive materials.

3. Evaluate work habits, experimental and facility design. Bioassays are performed either by:

a. Analyzing samples of blood, urine, or tissue. OR

b. Monitoring the organ of interest to determine the presence and quantity of radioisotopes. The method chosen depends upon the type of radioisotope involved (e.g. urine analysis for 3H or thyroid scanning for 125I).