Not sure how many are familiar with black market Soviet vinyl on X-ray film, but it's a fascinating story.
en.wikipedia.org
Examples can be found on eBay.
I am surprised xray film was being tossed.
Of course the silver in it might have already been leached out.
X ray film usually has thick emulsion coating, and so usually has twice the silver in it as conventional film.
I still dabble in the old school wet darkroom in my basement.
In that wet photo technology you keep silver from going down the drain, as it messes up biologic proceses once in the wider environment.
And there are still companies that will pay you for silver recovery cartridges.
You mail them away once you dry them out.
Basically a flow through can of steel wool.
Fe iron ion binds with what the Na silver ion was linked to, and the silver, by now metallic, plates onto the remaining elemental steel.
Or falls as black sludge to the bottom of the container.
You can mix a solution to strip the emulsion off raw film.
Basically break down the gelatin that holds all in place.
I sometimes use xray film to make enlarged negatives for way old school contect exposure processes.
It can be bought cheaply and in large sizes.
Then recover the xray film silver when I am done woth them.
Xray fills the recovery cartridge faster.
You dont get rich this way, but do make a few bucks and know you are doing the right thing.