[Comparative study of Acid extraction tests of metal products containing lead]

The international standard ISO 8124-3: 1997 "Safety of toys -Part 3: Migration of certain elements" and "Interim Enforcement Policy for Children's Metal Jewelry Containing Lead- 2/3/2005" by the U.S. Consumer Product Safety Commission (CPSC) to control the amount of eluted lead from metal accessories cannot be simply compared, because the acid extraction methods and the limit values are different from each other. Therefore acid extraction tests based on the ISO standard and the CPSC policy were conducted and the amounts of eluted lead from small metal products were compared between both tests. There was less eluted lead in the ISO method than in the CPSC method. Moreover, the amount of eluted lead in the ISO method did not even reach that of the first elution in the CPSC method. It became clear that the acid extraction test of the ISO standard was not as good as that of the CPSC policy, because of the difference in test conditions. In 16 small metal products, seven products were unsuitable for the ISO standard and 14 products were unsuitable for the CPSC policy; however, all these products were originally inapplicable to the ISO standard and the CPSC policy. The calculation grounds of the limit values were also different between the ISO standard and the CPSC policy. The standardization of an acid extraction test that simulates the lead elution to gastric juice is required so as to prevent adverse health effects in children due to their accidental ingestion of small metal products containing lead.