NRC – Stop Using Cesium-137 Irradiators
Late last week the National Research Council issued a report titled “Government should spur replacement of radioactive cesium chloride in medical and research equipment,” urging hospitals and universities, along with the developers of certain medical devices, to stop using the 1,300 machines that are used to irradiate blood for transplant patients. While the cesium-137 is usually contained in stainless steel capsules, the material is radioactive and if combined with conventional explosives could become a dirty bomb or radiological dispersal device.
At a time when the number of these devices is increasing the disposal of the material is problematic.
About 400 of the cesium chloride irradiators in use in the United States were made by Canada's MDS Nordion, said Leonard Connell of the US Department of Energy's Sandia National Laboratories in Albuquerque, a member of the panel that produced the report. The number of cesium chloride irradiators appears to be on the rise in the United States, the report said. In addition, Connell said, there is no disposal facility for them in the United States.
The report argued that the storage of such large amounts of the deadly ingredient in potentially attractive targets poses a threat. Again, according to the NRC report, the concern over the toxicity of the cesium-137 is very real. Some might ask if it worth the concern? The report argues that phasing out the use of the material, especially in light of the on-going concern over the threat of a dirty bomb, is warranted.
Eight radionuclides account for more than 99 percent of the sealed sources that pose the highest security risks in the United States. Cesium-137 in the form of cesium chloride poses greater concern than the others because it is widely used in significant quantities and is soluble and dispersible. If ingested or inhaled, it delivers a dose to the whole body. The concern about the availability of sources is exacerbated by the lack of permanent disposal options, which increases the likelihood that unwanted cesium-137 will remain in storage where it could be vulnerable to theft, the committee emphasized.
The NRC is usually pretty objective and especially since they acknowledge that alternative, safer materials, including other forms of cesium could be used as substitutes, industry and academia should listen - - - “Possible options include less-hazardous forms of radioactive cesium (not currently commercially available), radioactive cobalt and other chemicals that cost more but work just as well in medical and research equipment, according to the council's report.” Frankly, I would probably conclude that the threat is real and the concern is valid.
The NRC offered a number of steps to achieve the phasing out of the cesium-137 that include the stoppage of licensing new cesium chloride irradiators (including their import/export), create government incentives for owners to decommission and dispose of the radioactive sources and devices, provide incentives to lower the cost of less dangerous materials, and possibly to create a government buy-back program (that’s a big WOW with the estimated cost of each irradiator being $200,000).
Is it worth the concern? Is it worth $260 million? It might be, considering the continuing threat of a dirty bomb, despite the fact that the real threat of a dirty bomb probably lies more in the bomb part of it.