In January 2006, small amounts of genetically engineered rice turned up in a shipment that was tested ... by a French customer of Riceland Foods, a big rice mill based in Stuttgart, Ark. Testing revealed that the genetically modified rice contained a strain of Liberty Link that had not been approved for human consumption. What's more, trace amounts of the Liberty Link had mysteriously made their way into the commercial rice supply in all five of the Southern states where long-grain rice is grown. Aventis Crop Science had contracted with a handful of farmers to grow the rice, which was known as Liberty Link because its genes had been altered to resist a weed killer called Liberty, also made by Aventis. Then, the French pharmaceutical giant that owned Aventis Crop Science decided to sell the U.S. biotech unit and abandon the very emotional business of reengineering the foods we eat. "We didn't want to take any chances," says a former Aventis executive. "We burned and buried enough rice to feed 20 million people." Last November, the USDA retroactively approved the Liberty Link rice for human consumption.