In the analytical lab we had been using dinitrophenylhydrazine, in very low concentrations, in the determination of trace aldehydes. When the previous bottle was almost empty, I found out it could not be reordered from our established supplier. One chemist showed me how little there was left, he had been banging the bottle against the bench to get the last gram out. I was about in shock, apparently less so than the compound itself, and advised don't do that again because it's like a cross between TNT and rocket fuel.

Then found out the DNPH was no longer available in dry form, packed under water now under a different part number and with a revised SDS.