A strain of genetically engineered wheat never approved for sale or consumption by authorities was found sprouting on a farm in Oregon, the U.S. Agriculture Department said on Wednesday.
The wheat was developed years ago by biotechnology company Monsanto Co. but never put into use because of worldwide opposition to genetically engineered wheat.
The most recent field test of such wheat was in 2005.
Roughly half of the U.S. wheat crop is exported and most of the crop is used in making food such as breads, pastries, cookies and noodles. USDA officials said the Food and Drug Administration determined years ago there is no health risk to humans from the strain, though.
“Hopefully, our trading partners will be very understanding,” Michael Scuse, the acting U.S. deputy agriculture secretary, said at a briefing with reporters.
Scuse said trading partners and major customers for U.S. wheat had been informed of the discovery over the past day.
Genetically modified crops cannot be grown legally in the United States unless the government approves them after a review to ensure they pose no threat to the environment or to people.
Monsanto entered four strains of glyphosate-resistant wheat for U.S. approval in the 1990s but there was no final decision by regulators because the company decided there was no market.
The genetically modified wheat sprouted this spring on an Oregon farm, in a field that grew winter wheat in 2012.
When the farmer sprayed the so-called “volunteer” plants with a glyphosate herbicide, some of them unexpectedly survived. Samples were then sent to Oregon State University and to USDA for analysis.
Testing showed the wheat was a Monsanto-developed strain resistant to glyphosate. Monsanto is assisting in the investigation, USDA said.
Monsanto tested Roundup-Ready wheat varieties, those resistant to spraying by the widely-used herbicide, in 16 states from 1998 to 2005, said USDA.
Scuse and Michael Firko, who oversees USDA's biotechnology approval process, said USDA was investigating how the strain appeared on the farm when no seeds should have been available for several years.
“I think it will have a significant impact,” said Ronnie Cummins, national director of the Organic Consumers Association, which battled to keep genetically modified wheat out of the marketplace years ago.
The U.S. Senate last week rejected by a wide margin a measure to allow states to order labeling of food made with genetically engineered, or GE, crops. Cummins said the discovery of the rogue plants in Oregon would accelerate efforts to require GE food labels.