Migration tests of cadmium and lead from paint film of baby toys

Abstract

The migration tests of cadmium (Cd) and lead (Pb) from paint film on baby toys set out in the Japanese Food Sanitation Law (official standard) and International Standard 8124-3 (ISO) were compared. Vinyl chloride resin enamel and acrylic resin enamel containing 1,000 mg/kg Cd and Pb on a dried basis were painted on glass plates and then dried. According to the official standard, the paint films on the glass plates were soaked in water at 40°C for 30 min and the solutions were analyzed by ICP-AES. Cd and Pb were below the limit of determinotion (<0.1 μg/mL) and were less than 1/5-1/10 of the official standard limits. When the solvent was changed to 4% acetic acid or 0.07 mol/L HCl, we found that 0.3-2.3 μg/mL Cd and Pb migrated from the acrylic resin enamel, but no migration was observed from the vinyl chloride resin enamel. Meanwhile, according to the ISO method, paint was scratched from the glass plates and the powder was soaked in 0.07 mol/L HCl at 37°C for 1 hr either with shaking and without shaking. The migration of Cd and Pb reached 310 to 910 mg/kg, i.e., 3.5-12 times more than the migration limits. Cd migrated more extensively than Pb, and they both migrated more readily from the acrylic resin enamel than from the vinyl chloride enamel. In conclusion, the migration test of Cd and Pb from paint films on toys based on the ISO standards is stricter than that based on the Japanese Food Sanitation Low.