Waste Technology Section
Source Recovery
What are the risks with sealed sources?
Having a small size, existing in a large number worldwide and looking like a normal piece of metal, sealed sources can too easily be lost, misplaced or fall out of control of the competent authority. If not properly managed, they can be a threat to human health and cause contamination of large areas of the environment. Exposure to large doses of radiation can be lethal, causing severe acute effects and, in lower doses, inducing cancer.
Sources that are no longer in use are usually called "disused" or "spent". If the sources cannot be traced to an owner/user they are called "orphaned". Worldwide, the number of sources that are considered spent, disused or orphaned is very large and warrants dedicated efforts for their management in a safe and secure manner. The risk involved with such sources has been perceived by the international community to be large and unacceptable. Within the IAEA, priority is given to assist developing countries through a subprogram for the management of disused sealed radioactive sources.
Disused sealed sources are frequently found in unexpected places. While the number of disused sources does not influence the consequences of an accident, it does, however, increase the likelihood of one occurring. The risk particularly increases when sources are taken out of everyday use or when sources are inappropriately transferred between two users or facilities. Illicit trafficking of sealed sources has also become of concern over the last decade. Several hundred sources have been reported lost, stolen or found abandoned. Every year several people are killed due to over exposure and several tens or hundreds are being exposed to unacceptable doses.