This standard specifies the limit index and inspection method of lead, cadmium, hexavalent chromium and mercury in plastic materials. It is applicable to all kinds of plastic materials, masterbatch and its products, including infant products, food contact materials, electronics and electrical, automobiles, furniture, etc. The standard aims to ensure the environmental protection and safety of plastic products and reduce the potential harm of these substances to human health and the environment through the limited control of harmful heavy metals. The corresponding determination methods and testing requirements are listed in detail in the standard to ensure that plastic products meet the national environmental protection standards.