21 Feb (NucNet): The US government should promote the replacement of radioactive caesium chloride radiation sources used in some medical and research equipment, according to a new report by the country’s National Academies’ National Research Council.
The report, unveiled yesterday, was requested by Congress because of concerns that devices containing caesium-137 and other high-risk radionuclides could be stolen for use in a ‘dirty bomb’.
Caesium-137 in the form of radioactive caesium chloride in stainless steel capsules is used in self-contained irradiators at hospitals and universities for blood irradiation and in biomedical and radiation research, as well as other industrial uses.
The report says replacements for radioactive caesium chloride and some other high-risk radioactive materials used in commercial devices are available, but they are more expensive, creating little incentive for users to switch.
For most applications, radioactive caesium chloride can be replaced by “lower-hazard alternatives” that will not change the performance of the medical and research equipment.
However, the report says alternatives should be implemented with caution, “ensuring that essential functions that the radionuclide radiation sources perform are preserved”.
The report says that eight radionuclides account for more than 99 of the sealed sources that pose the highest security risks in the US.
“Caesium-137 in the form of caesium 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 study was sponsored by the US Nuclear Regulatory Commission (NRC). The NRC said yesterday that the agency is already addressing many of the issues raised.
Further details are available on the National Academies’ web site (www.nationalacademies.org).
– Compiled by John Shepherd
