China, the world's toy giant, has asserted that latest lab tests have proven the toys recalled by US company Mattel Inc. for a third time are up to the Chinese and European standards and are 'safe' for children.

The problem was that the US imposes a different measurement of lead content from other countries, the General Administration for Quality Supervision, Inspection and Quarantine, the safety watchdog of China, said in a report.

The GAQSIQ said that China and most other countries determine the safety of toy based on the lead release, or the amount of lead dissolvable out of toy paint, which may be harmful to human health.

China requires the lead release should be kept under 90 mg per kilogram, which is in line with the international standard (ISO8124-3) and the European standard (EN 71-3). But the US adds an extra standard to limit the lead content to 600 mg per kilogram, the administration said.

On September 4, the world's largest toy maker Mattel recalled 848,000 Chinese-made toys, after having recalling the toys twice, 85 per cent of which were due to design and 15 per cent for quality concerns.

The third recall of China-made toys by Mattel concerned 675,000 Barbie toys from a toy maker in Shenzhen in the southern province of Guangdong.

The product quality watchdog, however, said it would make further investigations into the matter as different labs produced "quite different" results, with some claiming the recalled products were substandard.