Not good. Have some stored in a brown plastic container from a few years ago. Got this unrelenting head/lung issue so tried the saline flush with no good results. Broke out the silver stash my wife made 2-3 years ago. Did the nasal sinus thing and it burns like hell. Figures it's cause my sinuses are jacked. After doing that It smelled like China, here where you burn your crap a lot of people burn plastic. So a couple days I realize it's actually this stashed silver crap eating at the plastic (I assume) So it still works kinda but the plastic burning in my sinus just isn't right. Need to make more in a glass container but just thought I would throw this out here. Sheesh.