China has sent back more than 100 tons of powdered milk made in the United States because it contained excessive nitrite.

The 102,000 kilograms of milk powder, produced by West Farm Inc., was worth about 200,000 U.S. dollars, according to the General Administration of Quality Supervision, Inspection and Quarantine.

The Beijing Entry-Exit Inspection and Quarantine Bureau said the Chinese company imported the milk powder as raw material for making chocolates.

Samples from the three batches of imported milk powder were found to contain 2.8 mg, 4.4 mg, and 2.7 mg of nitrite for every kilogram of milk powder, exceeding the allowable limit of nitrite in milk powder of two mg per kilogram, the administration said.

All of the powdered milk in question had been returned to the United States under the supervision of the administration and none had entered the Chinese market, the administration said in a statement.

Imported food must pass the quality supervision checks and meet China's national standards before entering the Chinese market, said Li Yuanping, director of import and export food safety.

Excessive nitrite intake can cause methemoglobinemia, which reduces the oxygen-carrying capacity in the body, dilatation of blood vessels and reduced blood pressure. An intake of 0.3 to 0.5 grams of nitrite can lead to poisoning of an adult and three grams to death.

In June 2002, a Wyeth brand milk powder designed for babies aged three to seven years was recalled from China because it contained excessive nitrite levels of 2.25 to 3.83 mg in every kilogram. The powder was produced by the U.S.-based Wyeth Irish affiliate.

In June last year, Swiss food maker Nestle issued an apology for violating government limits on iodine content in infant formula sold in China.

Chinese standards set a limit of 30 to 150 micrograms of iodine per 100 grams of milk powder. The Nestle product contained 198 micrograms of iodine per 100 grams. Excessive iodine can lead to a swollen thyroid gland.
 
Editor: Yan