Efforts to trace shipments of a bioengineered corn unapproved for human consumption have raised concern among food and grain industry officials that the corn which has already been discovered in two brands of grocery products may have made its way more widely into production channels for the nation's food supply.
Millions of bushels of the unapproved corn, known as StarLink, have been delivered to more than 350 grain elevators around the country. Government and industry officials, uncertain how much of the corn has been properly segregated and identified, are now pushing the operators to test their supplies for evidence of contamination.
There is no evidence that the corn causes health problems in humans, but the discoveries have led to nationwide recalls of two brands of store-bought taco shells, a move that was extended yesterday to a larger group of brands and products.
Food companies, many of which are now testing every shipment of corn for signs of the unapproved grain, have reacted with dismay to growing evidence of contamination, saying that it demonstrates a breakdown in the procedures intended to keep products grown from genetically modified seeds separate from conventional grains.
"This whole system has been self- policing by the seed industry," one food company executive said, speaking on condition of anonymity. "And obviously it hasn't worked."
The concern about StarLink has strained relations between the nation's grain companies and the developer of the corn, Aventis Crop Science, a subsidiary of Aventis S.A. of France. For example, according to a communication to the organization's members, the National Grain and Feed Association has demanded that the company reveal the names of the more than 2,000 farmers growing StarLink crops, information that would allow the industry to track potentially contaminated shipments more quickly.
But those requests have been refused. The grain association has since filed a request with the Environmental Protection Agency under the Freedom of Information Act, seeking the names of those farmers.
The StarLink corn is engineered to produce a protein toxic to a common pest, the corn borer. It was cleared for animal feed or industrial products in 1998, but the E.P.A. withheld approval for use in food meant for human consumption because tests showed properties indicating that it might cause allergies.
On Sept. 29, shortly after the first detection of contaminated taco shells, Aventis CropScience said it had reached an agreement with three federal agencies to work together to buy up all of this year's StarLink crop and to ensure that it had not entered the food supply.
Since then, the company has contacted the farmers, urging them to store the corn until further notice and questioning them about how the product had been handled.
What was found, according to industry officials who have been briefed on the results, is that not all farmers had signed required contracts obligating them to follow certain procedures intended to keep StarLink out of the food supply. As a result, the company is now urging elevator operators to begin testing corn shipments for the presence of the modified grain.
"This is a very sensitive matter, and everyone's role in preventing StarLink corn from entering unapproved channels is critical," John Wichtrich, vice president and general manager of Aventis CropScience, wrote to elevator operators. In the letter, Mr. Wichtrich urged the elevator operators "to take those measures you believe necessary to insure that the corn you purchase is suitable for the use you intend."
Mr. Wichtrich did not respond to a telephone message seeking comment.
Among the measures the company recommends is that elevator operators ask corn growers about each delivery to determine if it contains StarLink, or if it was grown less than 660 feet from a crop of the bioengineered corn. Corn fields grown in that proximity risk contamination by the bioengineered crop. While Aventis informed farmers that "buffer zones" of that size were necessary between StarLink and other corn crops, some farmers have been found not to have strictly adhered to the instruction.
"The food industry is very concerned that StarLink has contaminated a larger portion of the grain supply," one government official involved in the matter said.
Two grain industry officials said that based on the information they had received, as much as 100,000 acres of corn may have been grown within the buffer zones, in addition to the 315,000 acres for which StarLink seed was sold.
In the scramble to keep StarLink out of the food supply, a cottage industry has emerged in the last two weeks for testing kits to determine evidence of Cry9C protein, which is present in the bioengineered corn. The kits, which are used to test corn grain but not processed food, are manufactured by Strategic Diagnostics of Newark, Del.
The most common kit, known as a strip test, is used by food and grain companies at the point of delivery, providing information within minutes whether a corn shipment has been contaminated with StarLink. An individual strip test is designed to detect the StarLink protein in concentrations greater than 0.25 percent, although the sensitivity of the test can be improved by repeating the test or by increasing the number of kernels of corn sampled from 125 to as many as 400.
At a meeting on Tuesday with officials from the Department of Agriculture, the Environmental Protection Agency and the Food and Drug Administration, the company spelled out details of its contacts with 2,070 farmers who have grown the StarLink crops.
In the presentation, according to industry executives who have been briefed on the results, Aventis CropScience said that it had determined that 10.7 million bushels of StarLink had been fed to livestock, while 47 million bushels remained on the farm or unharvested. Slightly less than nine million bushels has been delivered into commercial channels.
Altogether, the StarLink grain represents roughly one-half of 1 percent of this year's corn harvest, which totaled more than 10 billion bushels.
In registered letters to growers of StarLink, the company has urged them to keep the bioengineered corn stored on the farm until they receive further instructions about where it should be delivered. The farmers will be paid a premium over the market price for the corn in exchange for keeping it stored.
The StarLink corn was first found last month in store-bought taco shells distributed under the Taco Bell brand by Kraft Foods, which issued a nationwide recall. On Wednesday, a similar finding was made in house-brand taco shells sold by the Safeway supermarket chain. The two products were made of yellow corn from the same mill, run by Azteca Milling in Plainview, Tex.
Yesterday, Mission Foods, which produced the Safeway shells, announced a recall of all its tortilla products made with yellow corn on the chance that some might contain StarLink corn. The company, a subsidiary of the Gruma Group of Mexico, which is based in Irving, Tex., sells products under the Mission name as well as numerous private- label brands.
Mission declined to name which other major grocery chains carried its private-label products, citing confidentiality agreements.
"This is a voluntary recall but we have strongly recommended it to them," said Peter Pitts, a spokesman for Mission. "We did this after conversations with our customers and the F.D.A. It's prudent. The most important thing is confidence in the safety of the food chain."
The company said it stopped buying corn on Sept. 23 from the Plainview mill. Now it plans to take the additional step of making all of its products from white corn "until there is clarification from the government on the safety of the yellow corn supply."
Azteca Milling, also a Gruma subsidiary based in Irving, announced its own voluntary recall of all yellow corn flour yesterday. Dan Lynn, the company's president, said it would mill only white corn because that was the "surest way to bolster confidence" that no corn unapproved for human consumption had entered the food chain.
All efforts to keep StarLink out of the food supply entail costs, whether for testing kits, storage or diversion of corn purchased for food into channels for feed. And already, in preparation for potential litigation, grain operators and food companies are reviewing the original registration for StarLink that the E.P.A. granted Aventis. That registration was effectively revoked earlier this week, grain and food companies are hoping but it can be used to force Aventis to pick up the ultimate cost of the current effort.
For example, one term in the registration states that Aventis "is liable for the actions of its customers in regard to meeting the terms and limitations of this registration."
In a communication this week with grain processors and elevator operators, the grain and feed association cited that statement. "Thus," the association wrote, "companies may wish to carefully document for future action instances in which StarLink corn was unknowingly delivered to a facility."
** NOTICE: In accordance with Title 17 U.S.C. Section 107, this material is distributed for research and educational purposes only. **
Last Updated on 10/18/00