I've recently moved into a new apartment that has a fireplace. I do
not intend to use the fireplace, so I've put a small tv stand in front
of it and it has a sort of wire mesh in front of it with a slit
through the middle and I wrongly thought that would be enough to deter
the kitty from exploring. Though, one day I walk into the living room
only to see the bottom half of my cat sicking out of the fireplace
while the other half I can only assume was trying to climb through the
flue. After a stern scolding, she ran away, but I've noticed little
sooty paw prints around the house and as I spend most of my day at
work I can only assume that she's been exploring again. I know she
can't get out through the fireplace and the flue is closed so she
can't get stuck. However, my question is since she has to lick the
stuff off her paws is it any health danger to her?

I've used twisty seals to try and close up the division in the meshy
thing to keep her out but she could still go around the sides if
thoroughly motivated enough.