Radioactive Iodine-131 is commonly used in the treatment of thyrotoxicosis. Approximately 99% of its degradation (radioactive decay) occurs within:
1) 26 days
2) 36 days
3) 46 days
4) 56 days
📝 Explanation:
Iodine-131 half-life ≈ 8 days.
After ~6 half-lives, >9899% of the isotope is degraded.
8⋅6 = 48 days → closest option is 46 days.
This is clinically relevant because it determines radiation safety precautions and therapeutic monitoring in patients receiving I-131.
MCQ