Abstract: An improved radiation dense container for transporting radioactive iodine and the like, including a cup-shaped base having a cavity with an opening that is sized to receive radioactive iodine in the form of either one or more iodine capsules or a vial of iodine solution. The vial has a cap with a septum through which the radioactive iodine solution can be withdrawn from the vial in situ by an oral radioisotope administration set. A lid threadedly engages the base over the cavity opening to substantially seal it when threaded in place and to allow the insertion and removal of the radioactive iodine when removed. The base and the lid are both formed of tungsten. The container includes one or more activated charcoal filters to absorb any gases given off by the radioactive iodine when sealed in the cavity. An inner cup-shaped container and cap, made of plastic and sized and configured for a close fit within the base cavity, may be utilized to conveniently hold the capsules or, optionally, the vial.