Reports out of China claim that milk powder produced by Sanlu Group Co. may have been tainted with the chemical melamine and could be linked to kidney stones in infants.  According to the Xinhua News Agency, Sanlu Group recalled 700 tons of milk powder after more than 50 babies suffered kidney stones and one died.

The Food and Drug Administration is warning American consumers to avoid infant formula from China.  Although Chinese formula is not approved for importation into the United States, it might be sold at ethnic grocery stores.

Chinese products have been at the center of safety incidents involving tainted toothpaste, toys, pet food and other products that caused deaths or injuries.  Melamine is the chemical involved in a massive pet food recall in the United States in 2007.  A settlement was reached in a consolidated class action filed by pet owners earlier this year.  A settlement hearing is set for Oct. 14 in that case.

Melamine is not supposed to be added to food, but suppliers in China allegedly mix it in to make products appear to be high in protein because it is nitrogen rich, and tests for protein in bulk food ingredients measure levels of nitrogen.