China probing cases of tainted baby formula

China's health ministry announced Friday a probe into the safety of all infant formulas, as a team of investigators from six government agencies descended on the milk powder factory that produced formula now linked to one baby's death and kidney problems in at least 50 more.

The producer of the suspect formula, the Sanlu Group, recalled 700 tons of its formula after determining on Thursday that it had been contaminated with melamine, an industrial chemical.

The official Xinhua news agency cited Zhao Xinchao, the vice mayor of Shijiazhuang in Hebei province, where Sanlu is based, as saying that police have already questioned 78 people, including dairy farmers and milk dealers. The police suspect that milk may have been diluted with water to increase the total volume for sale to Sanlu, and then added melamine to disguise the dilution, Zhao told the news agency.

A common industrial test for the protein content of dairy products or animal feed gives an inaccurately high reading if melamine is present.

In the United States, the Food and Drug Administration said that no infant formula from China has been approved for import. But the FDA advised consumers to be cautious since limited quantities might have found their way into some ethnic grocery stores.

The police suspicion in China that dairy farmers used melamine could also force a broader examination of foods imported from China that contain milk. The discovery of contaminated infant formula in China is a setback for the country's efforts to reassure its own citizenry and overseas buyers that the “made in China” label is trustworthy.

Contamination with melamine is especially embarrassing for the Chinese authorities. Pet food made from Chinese ingredients contaminated with melamine killed thousands of pets last year in the U.S., and China promised at the time that it would prevent melamine from entering food products for people.

China's health ministry promised “serious punishment” on Friday for those found responsible for the presence of melamine in the formula. The majority of the babies who have fallen sick had definitely been fed the Sanlu formula, the ministry said in a statement on its Web site.

Sanlu officials did not answer calls to eight different phone numbers at the company's headquarters on Friday.