The emergency shutdown of the Atomic Energy of Canada Ltd's National Research Universal (NRU) reactor at Chalk River ON will last much longer than originally anticipated. The NRU — contracted by MDS Nordion, Kanata ON, to produce the majority of medical isotopes used for medical procedures in North America — will now remain idle for at least three months. The interruption halts treatments for thousands of patients and will costs MDS more than $4 million a month in foregone revenue. The shutdown was caused by a heavy water leak. The NRU is one of four reactors globally producing commercial quantities of molybdenum-99. MDS says a significant shortage is certain and that it is examining its limited options for alternative sources of supply....