Paints and glazes labeled "food safe" or "lead-free" can be used on dinnerware. However, the paint or glaze must cover the entire surface of the dishes.
Ceramic dinnerware can leach lead and other contaminants if even the smallest speck of surface remains insufficiently covered by paint or glaze. Therefore, it is best to start with smooth pieces unmarred by cracks, crevices or rough patches that might be difficult to cover.
Use caution when purchasing earthenware pieces already painted or glazed by private artisans outside of the United States. The Food and Drug Administration warns that even pieces marked "lead-free" or "food safe" can be dangerous if they were fired in kilns previously used to fire pieces with lead-based glazes.