Governments and the private sector should develop a more effective system for securing radiological sources and accelerate work to replace radiological materials in medicine and other sectors with alternative technologies, where feasible, according to a report released yesterday by the Nuclear Threat Initiative. “This is the case particularly for the use of one of the most dangerous isotopes – cesium-137, which is used primarily in medical equipment,” the report states. “X-ray technology, which does not require the use of radioactive sources, is the most common and widely available alternative to cesium-137 used in blood irradiation. All hospitals should replace these irradiators to reduce risk and potential liability if the radiological sources are stolen.” Irradiators are used to irradiate blood prior to transfusion. The report looks at progress since the 2014 Nuclear Security Summit, when the U.S. and 22 other nations pledged to secure their most dangerous radiological sources by the end of 2016. While all but one of the countries is expected to meet that commitment, “much more needs to be done by many more governments and by the private sector to effectively secure and prevent the theft of radiological sources,” the report concludes. President Obama will host a fourth and final Nuclear Security Summit March 31-April 1 in Washington, D.C.