Safety Alert on U.S. Feed Export Turns the Tables

The U.S. Food and Drug Administration has alerted health officials in more than a dozen countries about U.S.-made shrimp-feed products that could be contaminated with small amounts of a potentially dangerous chemical, a turnabout likely to complicate the debate over the safety and export of food.

The chemical, melamine, is used in plastics and fire retardants, but it isn't allowed to be added to food in the U.S. or in China. It is the...