I had the original Warhammer figurines as a kid that my older brother didn't want. I remember bending the metal (I was maybe 4 or 5) and putting it in my mouth for some reason like I did with lego when I couldn't snap a piece off. I ended up swallowing a piece and vomiting up a bit of eldar soon after. Still have pleasant associations with the smell of lead thanks to warhammer.
I mean playing with small amounts of elemental mercury is pretty safe. Yeah it's toxic but if you play with it in your hands once or twice in your life nothing is going to happen.