Jacksonville restaurateur Elaine Wheeler pays attention to how farmers grow food. Her vegetarian Heartworks Gallery and Cafe buys fresh produce only from farmers who grow organically and limit their use of pesticides.
But Wheeler has decided she needs to learn more about agriculture, after discovering last week the taco shells she buys include StarLink corn, a genetically altered variety approved for livestock but not for human consumption.
For now, Wheeler's supplier has switched taco shell brands. Meanwhile, farmers and other food producers are backing away from the production of genetically altered foods -- afraid a public backlash will saddle them with products they can't sell.
Farmers and researchers say genetic engineering helps them grow better food more efficiently and at less cost.
But opponents, including environmentalists and organic farmers, claim the technology could possibly harm people and the environment.
They say last year's controversy over StarLink corn finally awakened U.S. consumers to the risks -- and to what they call the government's inadequate oversight.
The corn is given a bacterium gene called Bt so it can produce its own pest toxin and require less pesticide. The government is concerned that the altered corn might trigger an allergic reaction in some people.
An environmental group found the corn being used in human foods last year. Companies and farmers had to scrap their products, leading to billions of dollars in losses.
"It's easy to scare people," said Curt Hannah, a researcher at the University of Florida's Institute for Food and Agricultural Sciences. "Someone did a survey one time asking people, 'Do you want to eat plants with DNA?' And people said no."
But consumers deserve more information about how the food they eat has been altered, said Marty Mesh, executive director of the Gainesville-based Florida Organic Growers. The member farmers work about 10,000 acres in the state. They oppose the use of genetic engineering in agriculture.
Mesh said people allergic to nuts, for example, need to know whether they might be at risk for illness if they ate a food altered with a nut gene.
Critics also claim that altered plants could change the environment. For example, crops developed to resist a certain herbicide could cross-pollinate with weeds to create "superweeds" that then would force farmers to use stronger herbicides.
Mesh noted that two university studies last year concluded the pollen of Bt corn may pose a toxic threat to the monarch butterfly caterpillar, though later studies found caterpillars were at no greater risk from the corn.
Some farmers are confounded by the brewing opposition.
"The hope was we would be able to put a product out there the American public would think is wonderful because we weren't putting all these [chemical] products on it," said Hastings farmer Wayne Smith, who has grown genetically engineered potatoes and cotton. "Son of a gun, if they don't think that's a terrible thing."
Agricultural researchers have been inserting the genes of one variety or species into the cell of another since the 1980s, and farmers have been growing genetically altered plant varieties for several years, without much notice. A notable exception was olestra, the zero-calorie fat replacement first added to some snack foods in 1996. Products containing it had to start carry a warning because it might cause cramping and diarrhea.
Scientists are developing crops with higher yields, better taste or looks, and resistance to bugs and viruses so farmers can reduce their use of pesticides. Researchers also have created a more nutritious rice, and are experimenting with making plants that could fight human disease.
Hannah said the new technology is quicker and more precise than conventional methods, which include saving the seed of plants with favorable characteristics; cross-pollinating plants to get hybrids; "mutation breeding," which is the treating of plants with chemicals to cause mutations, then selecting the plants that produced favorable mutations; and the so-called "wide-crossing" of plants that would not successfully breed in nature. …