Nothing really. The civilian use cases for depleted uranium are well known.
https://en.wikipedia.org/wiki/Depleted_uranium#Civilian_applications
It’s used in dental porcelain for example. I have a mouth full of veneers and bridgework so I’ve probably got depleted uranium in my mouth all the time.
(Hey, I’m a Brit. I could’ve stuck with shocking Brit teeth and not bothered, but I chose the American Scary Bleach White Smile look. We call that “Hobson’s Choice.”)
And of course it was used in Boeing 747-100 construction.
Russia really is just trolling with this one - Depleted Uranium rounds on the battlefield (which lest we forget is a response to Russia creating a battlezone in east Ukraine - this wasn’t an issue before Feb 22) is less harmful to the environment and far less nasty than the magnesium alloy ML-5, and 9M22S rockets with thermite incendiary submunitions.
interesting that Russia is now concerned about DU, but had no problems with shelling the Zaporizhzhia nuclear power plant last year ...