Why should ceramic tableware undergo lead and cadmium migration testing?

Please verify the following points and require itemized written supplier responses:（ceramic tableware migration testing） Lead and cadmium migration testing assesses release under specified food simulant, time and temperature. GB 4806.4-2016 uses 4% acetic acid as the food simulant. Reports should show product type, batch, method, limits and conclusion, and should be reconfirmed when decals or glazes change. Define capacity, accuracy, materials and operating environment before requesting quotes on a uniform basis. Request specification sheets, test reports, certificates, maintenance manuals and spare-part lists. During acceptance, verify appearance, dimensions, functions, safety protection and packaging, and keep test records. Do not compare unit price alone; include customization, freight, spare parts, after-sales support and downtime risk. Keep written records of inquiries, confirmations, FAT, acceptance and warranty commitments.