"Our regulatory system is based on the most rigorous scientific information available, is credible, is defensible and will serve to protect the environment and public health," Jane Anderson, an Environmental Protection Agency official, told the Senate Agriculture Committee.
EPA is one of three agencies responsible for regulating genetically modified crops and foods, with the Food and Drug Administration and the Agriculture Department.
"We're very confident about the assurances that are put forward," said James Maryanski, biotechonolgy coordinator for FDA's food safety office.
Critics of the technology say the agencies depend too heavily on companies to conduct research and report problems, and that the science is not advanced enough to guarantee the safety of the food. Environmental and consumer groups are pushing the Clinton administration to require the labeling of foods that contain biotech ingredients.
In Europe, consumer uproar has prompted the European Union to begin imposing mandatory labeling for some foods with genetically modified ingredients.
"We don't know what the products will prove to be in the long run. To say we know is an expression of faith, not of knowledge," said Mark Silbergeld, a representative of Consumers Union.
Backers of genetic engineering insist it is not fundamentally different from traditional breeding, in which one plant might be cross-pollinated with a wild cousin to produce a hardier variety. Genetic engineering involves splicing a single gene from one organism to another.
A major concern of scientists is making sure transplanted genes do not cause allergic reactions. Biotech ingredients, primarily from soybeans and corn, already are in wide use in supermarkets and fast-food restaurants, in everything from tortilla chips to soda and baby formula.
When consumers realize that, they will demand such foods be labeled, Silbergeld said. "They want to make the choice for themselves."
The food industry fears such labeling would stigmatize genetically modified ingredients. The FDA does not consider biotech ingredients fundamentally different from conventional ones and says there is no need for the labels.
Half the soybeans that U.S. farmers are growing this year were engineered to withstand a popular weedkiller, and a third of the corn crop is biotech, having been altered to produce its own pesticide. There also are genetically modified tomatoes, melons and potatoes. Crops are in development that would be nutritionally enhanced or engineered to deliver vaccines or medicine.
American scientists and farmers have been surprised by the growing public resistance to genetic engineering in Europe. In Britain, where biotech products are derided as "Frankenstein foods," supermarkets have stared advertising their goods as free of genetically modified ingredients.
Concern about the technology has grown since a laboratory study at Cornell University found evidence that pollen from a genetically modified corn can kill larvae of the monarch butterfly.
EPA scientists knew that the pollen could kill insects but do not believe the butterflies, which feed on milkweed, not corn, would be exposed to the toxin outside the laboratory, said Anderson, director of EPA's biopesticides and pollution prevention division.
EPA is monitoring field tests of the corn and could impose restrictions on its use, if necessary, she said.
Written By Philip Brasher