Sudden radioisotope shortage threatens patient care.

Threatens Patient Care I n what members of the nuclear medicine community referred to as a ‘‘devastating’’ and ‘‘catastrophic’’ series of events, the Canadian supplier of more than 50% of the world’s marketed radioisotopes shut down its reactor in late November. The result was an immediate shortage of 99mTc generators that forced a scramble for alternative suppliers and drastic reductions in the numbers of nuclear imaging studies performed in North and South America and the Far East. At Newsline press time in mid-December, no resolution had been reached, and the effects of the shortages were being felt in almost every nuclear medicine department and practice. On November 18, Atomic Energy of Canada Ltd. (AECL) shut down its Chalk River, Ontario, National Research Universal (NRU) reactor for what was initially described as 5 days of routine maintenance. Twelve days later, when shortages were already being felt, MDS Nordion, which manages wholesale marketing and distribution of radioisotopes from the reactor, alerted customers to a more serious interruption in the supply of 99Mo used in the manufacture of 99mTc generators and 131I. MDS reported ‘‘a scheduled reactor maintenance shutdown has been extended to complete an upgrade to the electrical system, addressing a technical regulatory issue.’’ Although concerned with identifying stopgap supplies and/or identifying alternative procedures, most users were encouraged by the news that ‘‘an approval of the upgrade plan is anticipated shortly with a targeted return to full production in mid-December.’’ But only a few days later, a longer and indefinite delay in production was announced. On December 4, AECL explained in a press release that ‘‘a decision was made to remain in shutdown and make the modifications required for the installation of 2 new motor starters for the reactor cooling pumps, and to connect the motors to an additional back-up power supply.’’ However, AECL provided no firm date for when production could be expected to resume. In comments to the media, AECL official Brian McGee speculated on a 75% probability that the reactor would be in operation by the end of December and a 95% chance that it would return to service by the end of the first week in January. MDS Nordion, cognizant of the effect the announcement would have on customers worldwide, provided a more informative and sobering assessment on the following day: the shutdown would definitely extend ‘‘into January 2008.’’ As the media in both Canada and the United States soon reported, the NRU shutdown was in fact the result of noncompliance with safety orders that were part of the AECL license from the Canadian Nuclear Safety Commission (CNSC). According to the CNSC, the license was renewed in 2006 only after the AECL stipulated that a requisite emergency power system had been connected to the 50-year-old reactor’s cooling pumps. A routine inspection during the November 18 shutdown revealed that the system was not and had never been operative. ‘‘It was a surprise to us because our expectation was that it was in place and in service,’’ Barclay Howden, a CNSC director general, told The Canadian Press. ‘‘From a nuclear safety point of view, this is a very serious situation.’’ During an emergency government hearing on December 6, AECL representatives responded that they had believed the powersystem upgrade to be a recommendation and not a compulsory requirement. Because parts to complete the upgrade were not immediately available, the timeline for resumption of radioisotope production remained unclear. After the parts are acquired and installed, the reactor cannot go back on line until it is reinspected by the CNSC and, even then, the regular supply of radioisotopes will not resume for at least 1 week.