A. Iodized table salt is a ready source for potassium iodide, a very powerful restrainer. Whether the additives that PE expresses concern about would affect a developer and film one would have to experiment. It has been used for years for this purpose and some recent intertube explorations yielded no problems announced.
Originally Posted by AndreasT
B. "Forever." Like my potassium bromide, something like 25 years and doing just fine.