Tempest in a Taco Shell

Killer tacos they ain't. But so hot are the politics of genetically modified food that the folks at Kraft Foods last week took the extraordinary step of pulling tons of innocent-looking Taco Bell taco shells off the shelves. Reason? Someone may have been fooling with their genes.

It was the first recall of what the industry calls GM food--and others call Frankenfood. Critics have long warned that once bioengineered genes get into any part of the food chains there's no telling when they'll turn up on our plates. Sure enough, early last week Genetically Engineered Food Alert, a consumer and environmental group, reported that traces of DNA from GM corn not approved for human consumption had been discovered in Taco Bell's tacos. The corn, known as StarLink, contains a gene from a bacterium that makes the corn deadly to corn borers but not to cows. It was approved for use as cattle feed but not for human consumption, for fear it could trigger allergic reactions.

How did the tainted seed get into the tacos? They are sold by Kraft but made by a Mexican company whose corn comes from any number of U.S. farms. Farmers who grow StarLink do so on the condition that they'll keep it out of human food supplies--a promise that's easy to elicit but hard to enforce.

Kraft is pushing for new regulations that would prevent GM food not fit for humans from being approved for any use. Taco Bell, for its part, prefers to err on the side of caution. The last thing it wants is for taco eaters to start saying, "¡Yo quiero McDonald's!"

--By Jeffrey Kluger