Orphan Sources Overview
J. O. Lubenau
Orphan sources are radioactive sources that have escaped institutional control. Although the term is relatively new, problems caused by orphan sources date to the early days of the use of radium. Of the many differences between the problems associated with radium orphan sources and today's orphan sources, perhaps the most significant is the difference in the populations. At its peak, U.S. radium users numbered about 6,000 in contrast to 170,000 specific and general licensees using Atomic Energy Act materials. About 2,000,000 devices containing sources have been distributed to these licensees. Yearly, about 375 sources are reported lost, stolen or abandoned but it is believed that the actual figure is higher. The lack of available or inexpensive disposal options is resulting in many licensees placing unwanted sources into unplanned long term storage where they become vulnerable to loss, theft, or abandonment. This population may be as high as 25% of the total, or 500,000 sources. Orphan sources have caused radiation injuries and deaths and environmental radioactive contamination. Orphan sources frequently become mixed with scrap metals destined for recycling. When melted with the scrap metal they cause mill, mill product, and environmental contamination. Internationally, orphan sources are a recognized concern. In the U.S. there are no orphan nuclear power reactors but there are orphan radioactive sources. There have been no public overexposures from licensed U.S. reactor operations but the same cannot be said for material licensees. Do U.S. priorities reflect this?
This abstract was presented at the 34th Annual Midyear Meeting, "Radiation Safety and ALARA Considerations for the 21st Century", Orphan Source Session, 2/4/2001 - 2/7/2001, held in Anaheim, CA.