China has returned 272 heart pacemakers imported from the United States after they failed quality control inspections, China's top quality control agency announced on Monday.

The General Administration of Quality Supervision, Inspection and Quarantine (AQSIQ) said that the heart pacemakers, valued at about US$240,000 in total, were detained by the Shanghai Entry-Exit inspection and Quarantine Bureau at the end of April.

The administration said the pulse strength of the devices, made by St. Jude Medical Inc., was not in line with its indicated properties.

The difference between the testing parameters and the default ones exceeded the two-percent limit set by the Chinese technical authorities, the AQSIQ said.

The pacemakers pose potential threats to patients' lives as they could cause misdiagnoses, the statement said, citing unnamed doctors.

In 2001, China's State Food and Drug Administration (SFDA) launched an urgent investigation into four types of pacemakers produced by St. Jude Medical Inc. due to reliability issues. The investigation has resulted in banning pacemaker imports.

The quality control agency reported that they would ask the US producers to resolve the problems and improve the product quality. Imports will be resumed once the problems are resolved, said the AQSIQ.

An official from the AQSIQ said that, generally speaking, a ban can be rescinded within six months to one year.

China and the United States have seized a number of products deemed unsafe from each other this year.

The US blamed melamine-tainted wheat proteins from China for the deaths of cats and dogs in North America. The US also claimed that some Chinese toothpastes, tires and seafood were unsafe.

Meanwhile, China has seized orange pulp and dried apricots from the United States, claiming that it contained excessive bacteria, mildew and sulfur dioxide.

The international community commonly requires to raise product quality and ensure food safety, said Wei Chuanzhong, deputy chief of the AQSIQ.

The two countries have agreed on an initial draft of a memorandum on food safety cooperation. They will hold a second summit on product safety this September in Maryland.

(Xinhua News Agency August 21, 2007)