And what about the GM crops being field tested for pharmaceutical and industrial purposes?
The conclusion that these crops will comingle with traditional crops is not supported "by science, law, or practice," Mr. Novak says. Companies like Syngenta have a self-interest not to allow pharma and industrial biotech crops into the food chain, he says, if for no other reason than "because of liability for us as a company."
Syngenta uses several methods to keep experimental GM crops separate, including growing them in locations away from traditional crops. The GM crops also may be planted at a different time, meaning they wouldn't flower when traditional crops do, making cross-pollination impossible. Physical alterations, such as detassling corn, can also be used to prevent the spread of pollen.
But Jane Rissler, a scientist at the UCS and coauthor of the study, says these steps aren't enough. While she concedes that experimental GM crops are raised under tougher standards than other crops, the standards were only tightened recently.
"For many years they were not grown under as strict requirements as they are now, so in fact, contamination could have occurred then," she says in a phone interview. "And I fear it still could occur now."
With corn, for example, the possibility of gene flow from one variety to another is high. "Corn pollen can travel so far," Dr. Rissler says. The insistence of seed companies that their pharmaceutical and industrial farming is safe "is not convincing to us and frankly it's not convincing to the food industry," which, she says, has "suggested very, very strongly that [only] nonfood crops be used to produce pharmaceuticals."
The industry has already experienced the costs of letting unapproved GM crops enter the food supply.
In 2000, StarLink, a variety of GM corn designed for livestock feed and not approved for human consumption, was found in taco shells and other grocery items, causing a public fury.
StarLink was removed from the market and its manufacturer, the French drugmaker Aventis, was forced to pay millions of dollars in legal settlements to corn farmers and grain handlers whose businesses were damaged by the controversy.