💀, that stuff will kill ya dead pretty quick.
Some more info regarding hazards facing clean up efforts from this article at the International Business Times.
Live: Sodium Cyanide from Tianjin Warehouse Has Leaked into Underground Drain Water
Sodium Cyanide would not “cause a blast”... but, it sure as hell will complicate the cleanup. It generates Hydrogen Cyanide gas, which is fatal when inhaled even at very low levels.
Potassium Nitrate, on the other hand... would make one hell of a blast. This is the material that caused the Texas City ship explosion in 1947. That explosion broke windows in houses 20 miles away.
NaCN and TDI... yikes! I wouldn’t want to be on the Chinese cleanup crew.