Sodium cyanide is acutely toxic to any living thing.
Incredibly small amounts of cyanide can kill fish. For example, cyanide measured at between 20-80 parts per billion can kill rainbow and brown trout. The same amount would be fatally toxic to humans. A one month inventory then would consist of 18-20 tons of cyanide. The use of sodium cyanide at other mines throughout the United States has resulted in numerous environmental disasters .