What happened with StarLink corn?

Modern biotechnology has dramatically increased our ability to alter the agronomic traits of plants. Among the novel traits that biotechnology has made available, an important group includes Bacillus thuringiensis-derived insect resistance. This technology has been applied to potatoes, cotton, and corn. Benefits of Bt crops, and biotechnology generally, can be realized only if risks are assessed and managed properly. The case of Starlink corn, a plant modified with a gene that encodes the Bt protein Cry9c, was a severe test of U.S. regulatory agencies. The U.S. Environmental Protection Agency had restricted its use to animal feed due to concern about the potential for allergenicity. However, Starlink corn was later found throughout the human food supply, resulting in food recalls by the Food and Drug Administration and significant disruption of the food supply. Here we examine the regulatory history of Starlink, the assessment framework employed by the U.S. government, assumptions and information gaps, and the key elements of government efforts to manage the product. We explore the impacts on regulations, science, and society and conclude that only significant advances in our understanding of food allergies and improvements in monitoring and enforcement will avoid similar events in the future. Specifically, we need to develop a stronger fundamental basis for predicting allergic sensitization and reactions if novel proteins are to be introduced in this fashion. Mechanisms are needed to assure that worker and community aeroallergen risks are considered. Requirements are needed for the development of valid assays so that enforcement and post market surveillance activities can be conducted.

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By Allan Maurer, NC Biotech Writer

When technology impacts the food chain, sometimes the food chain bites back.

Those kinds of lessons were the theme for the second day of the recent two-day North Carolina Biotechnology Center AgBio Summit in Chapel Hill.

Former Aventis CropScience Chief Operating Officer John Wichtrich described for the attendees how the events surrounding the recall of genetically modified StarLink corn became the third-biggest media story of the year 2000.

StarLink, created by Aventis, included a genetic modification that incorporated into the corn plant the protein Cry9C from the soil bacterium bacillus thuringiensis (Bt). It was to kill caterpillars. Because it had never been included in a genetically modified product before, it came under close regulatory scrutiny. Ultimately, the U.S. Environmental Protection Agency (EPA) approved it for animal feed, but not human food, in 1998. The EPA expressed concerns that the StarLink protein could be a human food allergen.

Aventis licensed the Garst Seed Company to produce and sell StarLink seed.

Then, in the fall of 2000, StarLink was detected in taco shells made by Kraft Foods and sold by Taco Bell. The Washington Post reported the story. Asked by the media how much StarLink corn was considered acceptable in the food supply, an EPA administrator, Stephen Johnson, said, “None.” Any food containing StarLink would be considered adulterated and recalled.

That, Wichtrich told the AgBio Summit, started the panic. “That’s when we realized we were in for a long haul,” he said.

Death threats, recalls, lawsuits, Congressional hearings

Soon, the StarLink story was topped only by the presidential election and the Monica Lewinski scandal. “It was a big deal,” Wichtrich said. “I got death threats. More than 300 food products were recalled.  Containment efforts required 200 people. ” Lawsuits and Congressional hearings followed.

StarLink corn was found in exports, and that resulted in “a sharp decline in corn exports to major trading partners” such as Japan, Wichtrich said. “Ships literally turned around and were told to dump their corn into the sea.”

McDonald’s uses a corn product on its french fries and Anheuser-Busch uses it in its beer, Wichtrich said. “They tied up the sewer system in Philadelphia because of all the beer dumped.”

More than 40 people reported adverse effects to the U.S. Food and Drug Administration (FDA), including three deaths attributed to severe allergic reactions. The U.S. Centers for Disease Control and Prevention (CDC) believed that 28 cases were possibly StarLink related, although CDC blood tests ultimately concluded none of the people had reactions connected to the StarLink protein.

Aventis moved aggressively to fix the problem

The StarLink affair plunged the U.S. corn marketing and distribution network into disarray though 2001. Aventis initiated a series of moves though a program called the StarLink Enhanced Stewardship that included a buyback program, test kits, costs of cleaning, transport and storage. Aventis estimated the program would cost from $100 million to $1 billion.

Aventis negotiated settlements with federal agencies, state attorneys general, growers, seed companies, processors, breweries, fast-food restaurants and exporters. “We were careful to invite all the stakeholders into the process. And not one went to court,” Wichtrich said. While it cost several hundred million, at the time, its insurance covered the problem, although insurance companies no longer cover anything related to GMOs.

“The Attorney General said we set the gold standard for handling it,” Wichtrich noted. As a result, regulations changed, including a rule that DNA in a crop is not considered adulteration. Aventis got out of the crop science business, selling to Bayer.

Lesson learned, according to Wichtrich, included:

• Aventis  should not have accepted a split registration allowing StarLink only for animal feed use. Today, firms will not market a genetically engineered feed crop unless it is also approved for human consumption.
• Aventis should not have relied on smaller third-party companies to launch the technology. “It was a mistake to license a number of small companies to take it to market,” Wichtrich said. “We had the deep pockets. They were not helpful and we ended up having to do everything.”
• It’s important to cooperate with all the stakeholders if something goes wrong.
• It’s inevitable something like this is going to happen.

Wichtrich, who is also former president of Bayer BioScience Americas, is currently president of Wichtrich consulting.

To see an array of photos of the Summit, visit this Image Gallery.