Are there drugs in my corn flakes?

The food industry has already found out the dangers - and costs - of letting unauthorized biotech crops seep into the food supply. Now, another threat has emerged: seeds.

Traditional corn, soybeans, and canola seeds available for sale to American farmers have a tiny percentage of genetically modified (GM) seeds mixed in with them, a new study shows. The finding poses immediate challenges for farmers and nations trying to keep their crops GM-free.

It also raises key questions as GM acreage continues to increase worldwide. If the genie is out of the bottle for GM seeds approved for human consumption, what's to prevent other experimental GM crops from moving into the food supply? Do consumers want genes meant to produce drugs, plastics, and vaccines hiding in their corn flakes?

"There is no reason to believe that the transgenes detected in this study are the only ones moving into the traditional seed supply," concludes the study, released Feb. 23 by the Union of Concerned Scientists (UCS), a watchdog group based in Cambridge, Mass.

It also says GM crops not approved for human consumption have been and continue to be field tested, leaving possible the contamination of traditional varieties.

Not so fast, industry groups counter. The UCS study found levels of GM seeds varying from only 0.05 percent to 1 percent mixed with traditional seeds, they point out. Shipments regularly contain similar amounts of other "off type" seed varieties that have nothing to do with genetic modification. Nor are there any indications that GM-modified crops pose any health hazard, these groups point out.

They add that as biotech crops become commercialized, their seeds will naturally find their way into traditional seed lots - but at very small levels.

"It is expected they will be held to reasonably low levels by the quality assurance procedures," the American Seed Trade Association (ASTA) said in a statement.

In other words, "there are low levels that are there, but they're allowed under seed laws," says Christopher Novak, a spokesman for Syngenta, a multinational agribusiness that develops GM crops, in a phone interview. "There's not a question of safety because all of these products have been approved for food use."

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.

Not surprisingly, both seed producers and critics agree that no GM crops designed for nonfood use should enter the food chain. But the tricky question, experts suggest, is what level of GM seed deemed safe by the United States should be allowed in shipments labeled as non-GM seed?

"There is no worldwide uniform standard about what constitutes an appropriate level of seed purity," says Michael Fernandez of the Pew Initiative on Food and Biotechnology, an independent think tank. This fall, Pew plans to host a conference that will look at ways to set testing standards of GM crops and seed purity.

In the US, producers are required to reveal only how much "off-type" seed is mixed in with the labeled seed, along with any foreign substances, such as weeds.

These are "marketplace standards," Mr. Fernandez says. "They're not designed as safety standards." GM seeds approved for consumption would simply be listed as one of the other varieties present, he says. "The assumption is that no seed [on the market] is 100 percent pure."

However, GM "contamination" of traditional seed could become a problem for trade with nations who are much more skittish about GM foods, the UCS report suggests.

The British government announced Tuesday that it would allow the first commercial GM crop, a type of corn, to be planted there, despite howls of protest. The British Medical Association reported that GM foods were highly unlikely to be a health hazard. But a recent poll cited in the London Times showed that only 4 percent of Britons strongly favored GM food and would eat it, while 85 percent said GM crops would have a negative impact on the environment.

Skepticism also remains high in the rest of the European Union and Africa. Even in the US, Mendocino County in northern California voted last week to ban genetically engineered crops and animals. Other local governments are considering similar laws.

Last month, a meeting in Malaysia of more than 80 countries that have signed a UN protocol on biosafety agreed to require detailed labeling on international shipments of GM crops. (They did not deal with the issue of standard seeds that contain traces of GM seeds.) The US disagreed with the labeling plan, but because it has not signed the UN protocol it could attend the meeting only as an observer.

However, a report by the International Service for the Acquisition of Agri-Biotech Applications (ISAAA) shows "hope for the future that biotech is continuing to gain acceptance as people have more understanding of the safety of these products," Syngenta's Novak says.

Global acreage devoted to GM crops grew by 15 percent to 167.3 million acres between 2002 and 2003, according to the ISAAA. Nearly 61 percent of that acreage was in the US, and 99 percent was grown in just six countries (US, Canada, China, South Africa, Argentina, and Brazil). In a boost for GM crops, China just gave a green light for seven varieties of foreign-grown GM crops to enter its market.

The UCS report concludes that the mixing of GM traits into traditional seed supplies is "not entirely reversible," but argues that it can be "substantially reduced." More and deeper studies of GM "contamination" need to be done, the UCS says.

The UCS also calls for the Department of Agriculture (USDA) to conduct an investigation and for the USDA, the Food and Drug Administration, and the Environmental Protection Agency to amend regulations for GM pharmaceutical and industrial crops "to ensure that the seed supply for food and feed crops is not contaminated at any level with drugs, vaccines, plastics, or related substances."

These government agencies have yet to respond to the UCS study, Rissler says.

When samples of traditional corn, soybean, and canola seeds were tested by the Union of Concerned Scientists, the seeds were found to be contaminated with transgenic DNA at levels of roughly 0.05 to 1 percent. If these proportions were in US supplies, as much as 6,250 total tons of GM seeds would be entering the US food supply without proper labeling. A 1 percent level would be higher than the purity standards for certified soybean and canola seeds set by the Association of Official Seed Certifying Agencies (AOSCA), below:

Maximum contamination Hybrid corn Soybeans Canola
Inert matter 2.00% 2.00% 1.00%
Weed seed 0 0.05 25/lb.
Other crop seed No standards 0.60 0.25%
Other contaminants 0.50 0.50 0.25

SOURCE: Union of Concerned Scientists/AOSCA