JeremyR,
You are right. Even if cyanide is cleaned 100% by tomorrow, there are serious problems related to handling and holding at every level of the trade in exporting countries, mainly Phi, Ind, and other developing countries.
The cyanide problem is not only related to physiological damage on fish, but most important, its impact on coral reefs. No a trace of cyanide should be allowed in the collection of MO.
Peter has more information regarding concentration of CN in tested fish. It is true that tested fish with readings of CN lower than a certain concentration are considered negative.
jaime