GREAT BARRINGTON, Mass. -- On a recent morning, Cynthia LaPier parked her cart in the cereal aisle of a supermarket. With a glance over her shoulder and a quick check of the ingredients, she plastered several boxes with hand-designed stickers from a roll in her purse.
"Warning," they read. "May Contain GMOs (Genetically Modified Organisms)."
For more than a decade, almost all processed foods in the United States -- cereals, snack foods, salad dressings -- have contained ingredients from plants whose DNA was manipulated in a laboratory.
Regulators and many scientists say these pose no danger. But as Americans ask more pointed questions about what they are eating, popular suspicions about the health and environmental effects of biotechnology are fueling a movement to require that food from genetically modified crops be labeled, if not eliminated.
When asked if they want genetically engineered foods to be labeled, about 9 in 10 Americans said they did, according to a 2010 Thomson Reuters-NPR poll.
Labeling bills have been proposed in more than a dozen states over the past year, and an appeal to the Food and Drug Administration last fall to mandate labels nationally drew more than a million signatures. There is an iPhone app: ShopNoGMO.
The most closely watched labeling effort is a proposed ballot initiative in California that cleared a crucial hurdle this month, setting the stage for a probable November vote that could influence not just food packaging but the future of agriculture.
Millions at the ready
Tens of millions of dollars are expected to be spent on the election showdown. It pits consumer groups and the organic food industry, both of which support mandatory labeling, against more conventional farmers, agricultural biotechnology companies, such as Monsanto, and many of the nation's best-known food brands, such as Kellogg's and Kraft.
The heightened stakes have added fuel to a long-simmering debate over the merits of genetically engineered crops, which many scientists and farmers believe could be useful in meeting the world's rapidly expanding food needs.