October 6/USA TODAY -- No level of the chemical melamine, which has been found in milk from China, is acceptable in baby formula, the FDA has ruled.

In other foods, only a tiny amount -- 2.5 parts per million -- is considered acceptable, the agency says.

Formula tainted with melamine has killed at least four babies and sickened more than 54,000 children in China. It is now turning up in products containing milk proteins across Asia. In the U.S., White Rabbit candies imported from China have been recalled because of melamine contamination.

However, according to the FDA, no U.S. formula producers use ingredients sourced from China.

Melamine was added to watered-down milk in China to make it appear to have appropriate protein levels when tested.

Last year, the nation's largest recall of pet food occurred when melamine-contaminated foods were found to be injuring and killing dogs and cats. The chemical damages kidneys.

From the October 13, 2008, Prepared Foods e-Flash