Instructions for After Your Radioactive Implants of Iodine-125 for Localization

The radioactive implant that was placed in your body is a tiny metal seed containing radioactive material. It is about the size of a thin sesame seed. The seed is sealed, meaning that the radioactive material will stay in the seed. None of the items you touch, the people you come into contact with, or the clothes you wear will become radioactive. 

People who are in close physical contact with you may be exposed to very small amounts of radiation. While there is no evidence that this exposure causes harm, follow the recommendations below to minimize radiation exposure to others:

  • Distance. The amount of radiation coming from your body is very small. It decreases significantly when someone is 1 foot away from the implanted site. Almost no radiation reaches a distance of 3 feet away.
  • Time. Radiation exposure to others depends on how long you remain in close contact with them. You cannot harm anyone by hugging, kissing, or shaking hands. Avoid placing an infant or child on your chest for more than 30 minutes per day for 1 month after the seed is placed or until the seed is removed during surgery.

If you have any questions, please contact the Radiation Safety Service in the Department of Medical Physics at 212-639-7391.