BEIJING (AP) — Chinese authorities have ordered the recall of tainted leukemia drugs blamed for causing leg pains and other problems, state media reported Sunday, the latest crisis to strike the country's embattled food and drug industries.

 

Most of the drugs involved — methotrexate and cytarabin hydrochloride — have been recovered and authorities have traced the remainder, the Xinhua News Agency said.

 

Authorities banned the sale and distribution of the drugs, produced by the Shanghai Hualian Pharmaceutical Co. in early July after some patients complained of adverse reactions.

 

The announcement came as Chinese food, drugs and other products ranging from toothpaste to seafood are under intense scrutiny because they have been found to contain potentially deadly substances.

 

China has been eager to cast itself as a victim too of unsafe imports and Xinhua on Saturday announced that inspectors recently found residue of the banned stimulant ractopamine in frozen pig kidney imported from the United States and frozen pork spareribs from Canada. Ractopamine is forbidden for use as veterinary medicine in China.

 

Xinhua said the 18.37 tons of frozen pork kidney and 24 tons of frozen pork ribs had been returned to the exporters, said the General Administration of Quality Supervision, Inspection and Quarantine.

 

Ractopamine, a hormone that promotes the growth of lean meat in pigs and cattle, is banned by China and most other countries as a health hazard, although its use in stock animals is permitted in the United States. China has also banned imports of U.S. meat contaminated with salmonella, additives, and prohibited veterinary drugs.

 

The State Food and Drug Administration and the Health Ministry banned the two leukemia drugs after several children who were taking them complained of leg pains and experienced difficulty walking. Xinhua said some patients also complained of urine retention.

 

It said the Health Ministry and the drug regulator found the problems were caused by the medicine being tainted with vincristine sulfate, an anticancer drug. Xinhua said factories manufacturing the drugs had been closed.

 

China has taken a series of steps to crackdown on tainted drugs and other unsafe products, in part from concern over the reputation of its exports.

 

In the harshest action so far, the country's former top drug regulator was executed in July for taking millions of yuan in bribes to approve substandard medicines, including an antibiotic that killed at least 10 people.