Despite nationwide product recalls, traces of StarLink corn not approved for human consumption still turn up in 10% of grain samples.
The government is still investigating whether this corn can trigger life-threatening allergic reactions. CBS's Eye on America digs deeper in a hard-news investigation of gene-altered food.
Last fall, at a business lunch with co-workers, Grace Booth enjoyed three chicken enchiladas. The food, she recalls, was very good--but then something went very wrong.
"I felt my chest getting tight. It was hard to breathe," she says.
She didn't know it, but she was going into shock.
"I thought, oh my God, what is happening to me?," Booth recalls. "I felt like I was going to die."
In the emergency room in Oakland, California, the diagnosis was severe allergic reaction, and from here Grace Booth's story reached official Washington.
At the time, the national corn market was in an uproar. StarLink, a gene-modified corn not approved for human food, had been found in taco shells and recalls were emptying the shelves of corn products. The fear was possible allergic reactions.
At that moment, Booth says, she had no idea that the corn tortillas in her lunch were about to be recalled.
So when she went to the hospital, she didnt suspect that her reaction was due to modified corn. After the fact, she thought again about what had happened.
In the wake of the recalls, more than 50 Americans including Grace Booth claimed they had had reactions to StarLink corn. That forced the government to launch the first full-scale allergy investigation in the history of biotech food.
It has taken months, but the Centers for Disease Control and Prevention and the Food and Drug Administration have collected food samples and blood from two dozen people whose cases were believed most serious.
The complaints range from just abdominal pain and diarrhea to skin rashes in some patients, to very severe life-threatening reactions in a small group of people, says Dr. Marc Rothenberg, the allergy chief at Cincinnati Children's Hospital.
Rothenberg is an adviser to the government in the StarLink investigation. It's slow going, he says, because investigators first had to find the StarLink protein and then invent a blood test.
Even if the test shows allergic reactions, Rothenberg says he believes it's unlikely there's enough StarLink in the food chain to threaten the general public's health.
"My gut feeling was that this wasn't a significant concern--this was not going to be a major problem, like a peanut problem," he says, referring to the relatively large number of people who have severe allergic reactions to even trace amounts of the nut.
Right now the length of the investigation is what's eating at Grace Booth. She's waited 7 months for some answers.
"If I want a bowl of cornflakes, I want to know that it's safe to eat a bowl of cornflakes," Booth says. She says she does not feel that safe wih her food right now.
She still has half of a suspect enchilada. The government is testing the other half and says it will have results next month. Every corn farmer in America, every miller, every food maker, and the entire biotech industry now awaits the verdict on what it was that made Grace Booth sick.
In part 2 of this Eye on America investigation: Why some say trace amounts of StarLink should be allowed in food.
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