www.checkbiotech.org ; www.raupp.info ; www.czu.cz

With the use of transgenic crops expanding around the globe, we need to
decide what level of unapproved plants we are willing to accept in our
diets. Zero is not an option, says Heidi Ledford, January 2007.

Steve Linscombe still isn't quite sure how it happened. The director of
the Louisiana State University AgCenter for Rice Research knows that he grew
a few lines of transgenic rice in field trials between 2001 and 2003. He
also knows that one of those lines, LLRICE601, was grown on less than one
acre. What he is not clear on is how the line then wended its way into the
food supply. That little mystery is now the subject of an official
investigation and a class-action lawsuit.

When the escape was announced in August last year, LLRICE601 had not been
approved for human consumption. The US Department of Agriculture (USDA)
rushed to deregulate the crop, granting permission on 24 November for
LLRICE601 to be grown without a permit. By then, Japan had already declared
a month-long ban on all imports of US long-grain rice, and the European
Union had started to require all US long-grain rice imports to be tested and
certified at the expense of the exporters. Meanwhile, Bayer CropScience, the
company that created the rice strain, put the blame squarely on farmers and
an "act of God".

By that logic, this would not be the first time that a deity has aided and
abetted the escape of a genetically engineered crop. On 21 December,
Syngenta was fined $1.5 million for allowing its unapproved pest-resistant
Bt10 corn (maize) to mix into seed distributed for food. The past decade is
smattered with examples of unapproved crops sneaking through containment
barriers (see 'Some past escapes'). When they make it into the food supply -
as with LLRICE601 and Bt10 - public outcry and financial losses follow. But
amid the calls for tighter regulations, experts say one truth is being
drowned out: no amount of regulation can guarantee that these crops will not
escape and multiply.

Meanwhile, the stakes are getting higher. Since 1991, the USDA has approved
nearly 400 field tests of crops that produce pharmaceutical and industrial
compounds, leaving many concerned that future escapes could have severe
consequences for human health. A close call came in 2002, when stalks of
corn designed to produce a pig vaccine were found mixed with $2.7-million
worth of Nebraska soya beans destined for human consumption. Prodigene, the
corn's maker, was fined $250,000 and forced to buy and destroy the soya
beans.

No guarantees
Although the use of transgenic crops is spreading around the globe,
production is still concentrated in the United States, which grows more than
half of the world's genetically engineered crops. There, they are monitored
by three regulatory agencies: the USDA regulates field tests, the
Environmental Protection Agency monitors crops genetically engineered to
produce pesticides, and the Food and Drug Administration provides a
voluntary 'consultation' on the safety of crops for human consumption. That
voluntary consultation sets the United States apart from many other
countries, including China and many European countries, which require crops
to be evaluated for toxicity and allergenicity before being approved.

In the 20 years since the USDA started to regulate field tests, it has
approved nearly 50,000 field sites. But an internal audit commissioned by
the USDA inspector-general and released on 22 December 2005 was severely
critical. The report admonished the agency for lacking basic information
about test sites, failing to inspect field tests sufficiently, and
neglecting the fate of the crops after testing. USDA regulator Rebecca Besch
says that a year on, many of the report's recommendations have been enacted.
The agency now asks for detailed coordinates of field test sites, she says,
and is revising its environmental standards.

Jeffrey Wolt, an agronomist at Iowa State University in Ames, commends the
USDA for its efforts, but says that tougher regulations are no guarantee of
confinement. "There has been this strong effort by regulators and industry
to tighten this stuff up," he says. "But no matter how much you ratchet it
down, the risk is not going to be absolute zero because that's a scientific
impossibility."

Other scientists agree. Transgenic plants have many ways to escape. For
plants pollinated by wind and insects, such as canola, pollen transfer is a
constant threat. And although seed harvesting and processing equipment is
designed to keep different varieties apart, there is no guarantee of
success. "Just like anything, it is not 100%," says Linscombe. "You could
have a seed that gets caught somewhere in a planter and later jars itself
loose." And of course even if only a few seeds make their way into breeding
stock, their numbers can then multiply.

Meanwhile, says Michelle Marvier, an ecologist at Santa Clara University in
California, the focus on designing effective biological containment has kept
attention away from an even more slippery culprit: human error. "The reality
is that humans are involved, and we inevitably make mistakes." She warns
that any risk evaluation of a genetically engineered crop should consider
that crop likely to escape.

Several countries have opted not to take that risk. After the news of
LLRICE601 contamination, major exporters in Vietnam announced that they
would not be growing any transgenic rice. And even some countries that grow
genetically modified crops are cautious about the ones they will accept.
Argentina, for example, the world's second largest producer, refuses to grow
any genetically engineered crop that has not been approved for consumption
in its major export markets, including the European Union. That policy is
intended to prevent unintended mixing of crops from hurting Argentina's
robust agricultural export sector (although it hasn't protected neighbouring
Brazil - which did not allow genetically engineered crops until last year -
from repeated contamination from Argentina's transgenic stocks).

Harsh punishments
In the United States, the idea is that escape can be prevented if producers
know that they will be punished if unapproved plant material is detected in
the food supply. If a company is responsible for contamination, it typically
has to remove the unapproved material at its own expense, and as an
additional deterrent, deal with the flurry of negative press that
undoubtedly follows. "It is really bad for the reputation of these firms and
the technology itself," says Guillaume Gruere, an agricultural economist at
the International Food Policy Research Institute in Washington DC. But he
says that the regulatory agencies' zero-tolerance policy clashes with the
inevitability of escape. "The problem is the threshold. If you want zero
percent, it's going to be pretty much impossible."

And despite the negative press, US public opinion of genetically modified
crops seems to have been changed little by the escapes so far, judging from
the results of a survey done by the Pew Initiative on Food and Biotechnology
last year. The number of Americans who approve of genetically modified food
has hovered unchanged at around 26% for the past five years, whereas the
number that explicitly disapproves has shrunk from 58% to 46%.

What about crops that produce pharmaceuticals and industrial compounds? In
2003, the USDA issued stricter guidelines for containment of these plants.
Isolation distances from food crops were increased, and field test sites
were to be inspected more frequently. And so far, no such strains have been
deregulated, meaning that they must always be contained no matter how well
they are tested.

But Margaret Mellon, director of the Union of Concerned Scientists' Food and
Environment programme, doubts that those regulations will be enough. Her
organization has called for a ban on the outdoor production of
pharmaceuticals in food crops, arguing that the amount of regulation needed
to guarantee containment would be prohibitively expensive both to the
government and to researchers. The union has gone through the USDA
regulations and analysed points at which transgenic crops could still
escape, such as machine cleaning and seed transport. "Regulations that are
sufficiently stringent to plug all of those holes really are not feasible,"
says Mellon. "We see how much trouble the agency is having even with the
current ones." Instead, she argues, production of pharmaceuticals or
industrial compounds should take place only in non-food crops such as
tobacco.

The problem is that such a ban would have a chilling effect on research,
because the technology for creating and processing transgenic food crops is
well understood and therefore much cheaper. At this stage, a US ban seems
unlikely, and no other country has an official ban on
pharmaceutical-producing crops. In 2005, the Oregon Department of
Agriculture convened a panel to evaluate the risks and potential economic
benefits of growing animals and plants that produce pharmaceuticals in the
state. The panel concluded last October that the benefits outweigh the
risks.

Back in Louisiana, Linscombe plans to enact a few new regulations of his
own. After his experience with LLRICE601, he says that he will be taking
drastic measures to separate any experimental crops from his breeding stock,
to at least minimize the chance of contamination. He is considering buying
separate processing equipment for genetically modified crops. And he plans
to greatly exceed the typical three-metre distance that is required between
strains. "We have two farms that are located five miles apart," he says.
"Any transgenic work in the future is going to be on one farm, and the
breeding work on the other."

[www.nature.com]