Ceramics are mostly used as kitchen ware. As ceramics are made from natural materials such as clay, quartz and kaolin they may be contaminated with heavy metals. These have the potential to migrate into food contained within. Aside from being regulated under the EU ,  regulates the Specific Maximum Migration Levels (SML) of cadmium and lead into food. The directive further requires that the producer of ceramics declares on each product that it does indeed not exceed this migration limit. Ceramics regulation is currently being revised.