Wendy ~ You can buy all kinds of different paint that goes
onto mugs ,dishes,etc .... usually it is non toxic -- but I would read the labels just to be safe. Once ,I used the paint that was supposed to be permanent without baking it -- didn't last worth a darn . Now I buy paint that I can "bake"
and it's dishwasher safe & non toxic. Check in your craft store by the glass & mosaic supplies - and there is also some made by Folk Art by the regular acrylic paints that you can bake. Good luck & have fun !!!! :-)