I think yellow is actually fine - a lick is 3 seconds of contact maximum and you’re not sucking on it or ingesting it…
Sodium’s the only one you’ll ingest decent quantities of and it’s just gonna taste fizzy and soapy with no real lasting damage, stuff like lead you won’t even ingest and even if you did it’d probably be fine in such low quantities, even mercury is probably ok to lick if you’re careful
That said, with the radioactive ones you need to be careful of what isotope and sample size you’re licking, so licking a huge ingot of U235 would probably do some lasting damage just by being near it, but licking a small piece of U238 is more than likely fine so long as it’s solid and not dust
I think yellow is actually fine - a lick is 3 seconds of contact maximum and you’re not sucking on it or ingesting it…
Sodium’s the only one you’ll ingest decent quantities of and it’s just gonna taste fizzy and soapy with no real lasting damage, stuff like lead you won’t even ingest and even if you did it’d probably be fine in such low quantities, even mercury is probably ok to lick if you’re careful
That said, with the radioactive ones you need to be careful of what isotope and sample size you’re licking, so licking a huge ingot of U235 would probably do some lasting damage just by being near it, but licking a small piece of U238 is more than likely fine so long as it’s solid and not dust