The Chalk River reactor was shut down for almost a month in November and December over safety concerns, sparking a critical shortage of medical isotopes used in diagnosing and treating cancer and heart ailments.
Atomic Energy of Canada Ltd. provides isotopes exclusively to MDS Nordion, which then reprocesses them and sells them to pharmaceutical companies.
The report in the medical journal said MDS Nordion wouldn't co-operate with Europe's two-large-scale isotope suppliers Â– Nuclear Research and Consultancy Group in the Netherlands and the Institut National des Radioelements in Belgium.
However, a response posted on the CMAJ website by MDS Nordion spokeswoman Tamra Benjamin said the company immediately began to co-ordinate a backup supply of isotopes.
"Given that the extended shutdown of AECL's NRU reactor was a precipitous event, any type of advanced international schedule collaboration would not have mitigated this unplanned event," Benjamin wrote.
Her letter also takes issue with comments in the article from Alan J. Kuperman, a policy analyst with the U.S-based Nuclear Control Institute, that suggested AECL and MDS Nordion didn't want their competitors to pick up the slack, and chose to go to the public and government first instead of approaching other suppliers.
"On Nov. 23, in accordance with our existing supply agreements, MDS Nordion initiated communication with our competitors/backup suppliers in an attempt to mitigate the unplanned shortage by obtaining backup supply and placing orders for all available material," Benjamin said.
Noting that South Africa, the Netherlands and Belgium are the only three commercial sources of medical isotopes to call upon, Benjamin added their efforts included unprecedented conference calls with all three.
"All backup received by MDS Nordion prior to Dec. 14 came from South Africa. Despite our requests to other suppliers on Nov. 23, we were unable to obtain any backup supply from Europe before Bill C-38 was passed on Dec. 12."
Bill C-38 is the emergency legislation passed by Parliament that overruled the safety objections of the Canadian Nuclear Safety Commission, and allowed the Chalk River reactor to be restarted Dec. 16.
The CMAJ, however, is unmoved by the arguments laid out in Benjamin's e-letter.
"In short, nothing in the MDS Nordion e-letter undermines the fundamental tenet of the news article, which CMAJ stands firmly behind," wrote Deputy Editor Barbara Sibbald in a response posted on the website.