Steve Taylor practically yawned when researchers at Pioneer
Hi-Bred, the giant agricultural seed company, asked him in
1995 to study a new soybean they had invented. "I didn't
think we'd find anything interesting," the University of
Nebraska scientist recently recalled.
Little did Taylor know that his findings would help trigger
a wave of anxiety over the safety of genetically engineered
food in Europe, a wave that, years later, now threatens to
engulf the United States as well.
Pioneer had spliced a Brazil nut gene into soybeans,
creating a soybean that boasted a nutritious nut protein.
Taylor's task was to find out whether the new soybean would
cause allergies in people allergic to Brazil nuts, a
potential danger because people with allergies to nuts
wouldn't think to avoid soy.
The company had put just one of the Brazil nut's thousands
of proteins into its new soybean, and the odds of that one
causing the nut's allergies were incredibly low, Taylor
said. So he could hardly believe it when first one test,
then another, and finally a third indicated that the
transferred protein was indeed a major cause of Brazil nut
allergies.
In trying to build a better soybean, the company had made a
potentially deadly one.
Pioneer immediately halted the soybean project. But
Taylor's study lives on today as a symbol of everything
that is both frightening and reassuring about genetically
altered food, which has quietly made its way into nearly
every American kitchen.
Frightening because the study proved that a gene-altered
food could cause an unexpected and potentially fatal
reaction.
Reassuring because the problem was detected before the
product was marketed.
And symbolic above all because it was, and still is, one of
the very few studies ever to look directly for any harm
from an engineered food or crop.
That dearth of studies is the legacy of a U.S. policy that
considers gene-altered plants and food to be fundamentally
the same as conventional ones, a policy some Americans are
starting to question.
It is also the legacy of the sheer scientific difficulty of
conducting the kinds of tests that might assure people that
engineered crops and food are safe.
And it is the legacy of broken promises by the Food and
Drug Administration and the Environmental Protection
Agency, both of which have said for the past five years
that they intend to write rules to minimize the chances
that gene-altered food will cause allergies or damage the
environment.
"Americans are starting to realize that this process is not
as all wrapped up as they thought it was," said Carol
Tucker Foreman, a food safety specialist at the Consumer
Federation in Washington.
Genetically engineered food, which is endowed with
bacterial, viral and other genes not native to human food,
has been widely, if mostly unknowingly, consumed in the
United States since 1996. As far as scientists can tell, no
one has ever been harmed.
But with evidence accumulating that the crops may be less
environmentally benign than biotech companies had predicted
-- most recently, gene-altered corn was found capable of
killing monarch butterflies -- some Americans are
reconsidering the technology's overall safety.
"I've had more calls about this allergy research in the
past three months than I've had in the three years since we
published it," Taylor said.
In Europe, that crisis of confidence already runs deep.
Activists regularly vandalize newly planted plots of
gene-altered crops. Major grocery chains have refused to
carry engineered food. And food processors have begun to
hire DNA fingerprinting labs to verify that their products
are free of foreign genes.
The British Medical Association has warned that the
technology may lead to the emergence of new allergies and
speed the evolution of microbes resistant to antibiotics.
Other groups worry that gene-altered crops may lead to the
growth of insecticide-resistant bugs, or "superweeds"
unfazed by herbicides.
In this country, gene-altered food is virtually
unavoidable. About one-third of the corn growing in the
United States is genetically engineered, mostly to exude
its own insecticide, as is about half of the cotton crop
(including some grown for edible cottonseed oil) and a
smaller percentage of potatoes. Half of all U.S. soybeans
are genetically modified as well, mostly to produce a
chemical that makes the plants impervious to weed-killing
sprays.
So with the exception of explicitly organic food, which
flows through independent "identity-preserved" food
streams, nearly everything made with soy, corn or cotton in
this country ends up containing at least some gene-altered
ingredients.
That's a lot of different foods. Soy protein can be found
in about 60 percent of all processed food, including frozen
meals, baby food, yogurt and other products. And corn, in
addition to being the main ingredient in tortilla chips and
corn starch, provides the high-fructose sweeteners found in
many "natural" sodas, fruit drinks and other products.
U.S. regulators and industry representatives argue that
engineered food is, if anything, safer than conventional
food. Old-fashioned plant breeding involves the random and
uncontrolled reassortment of thousands of genes with every
mating, they note. By contrast, biotechnology allows the
precise transfer of a single well-understood gene into a
plant, leaving little to chance.
Moreover, they say, since 1992 the FDA has required allergy
tests like the ones Taylor did for all new food made with
genes taken from milk, eggs, wheat, fish, shellfish,
legumes or nuts, foods that account for perhaps 90 percent
of American food allergies. The agency also insists that
gene-altered food be nutritionally equivalent to its
conventional counterparts.
Most important, advocates say, the FDA can demand extensive
safety testing if the new gene "differs substantially" from
those generally found in other food. But critics call that
a hollow promise. They note that all 44 crops that so far
have gained FDA marketing approval have avoided that
scrutiny because the agency has accepted the industry's
claims that they are "substantially equivalent" to
conventional food.
That is, they claim, because the Food, Drug and Cosmetic
Act demands safety testing on all new additives not
"generally recognized as safe." Now activists are suing the
FDA in federal court to force such testing on the bacterial
and other genes being added to food crops.
Safety testing can be difficult, as researchers found with
the Flavr Savr tomato, which was given a gene to make it
ripen more slowly. When Calgene and Zeneca Plant Science
developed that tomato in the early 1990s, no FDA rules were
in place. So the companies voluntarily agreed to conduct a
full range of tests.
When scientists tried to feed rodents the tomatoes,
however, the animals wouldn't eat them, recalled Roger
Salquist, one of the scientists involved in creating the
Flavr Savr. "I gotta tell you, you can be Chef Boyardee and
mice are still not going to like them."
The researchers went so far as to force-feed the tomatoes
to rodents through gastric tubes and stomach washes. The
procedure made the rodents sick, of course, and revealed
nothing about the food's safety. The tomato ultimately won
approval from the FDA but failed in the market in part
because it was so expensive.
Safety testing is also difficult because there's no widely
accepted way to predict a new food's potential to cause an
allergy. The FDA is now five years behind in its promise to
develop guidelines for doing so. With no formal guidelines
in place, it's largely up to the industry to decide whether
and how to test for the allergy potential of new food not
already on the FDA's "must test" list.
That means there is a small chance that someone will suffer
an allergic reaction, and perhaps a serious one, but
science can never assure safety with 100 percent certainty,
said University of Wisconsin professor Robert Bush, chief
of allergies at the Veterans Affairs Hospital in Madison.
And when deciding how much effort and expense should be
rallied to minimize that risk, Bush said, people should
remember that new foods are introduced all the time from
other parts of the world without regulators demanding
studies on their allergy potential.
"I don't think there was a hue and cry about introducing
kiwis onto the U.S. market," Bush said, even though many
Americans have proven allergic to them.
The effects of gene-altered crops on the environment are at
least as complicated as those on the human body. The EPA
requires companies to conduct limited ecological impact
tests before marketing gene-altered crops. But while the
agency has promised to spell out in detail what crop
developers should do to ensure that their gene-altered
plants won't damage the environment, it has failed to do so
for the past five years.
Meanwhile, several recent scientific studies have
highlighted a of potential problems that may be arising
from engineered crops.
The most publicized of those was the recent finding that
pollen from corn that has been engineered to produce an
insecticide called Bt is toxic not only to the caterpillar
pest it is aimed at, but also to the monarch butterfly. The
laboratory study leaves unresolved whether monarchs are
actually being harmed around cornfields. But it inspired a
coalition of national environmental groups, including
several that had not weighed in on agricultural
biotechnology before, to ask the EPA to stop its
registration of new varieties of Bt corn until the agency
comes up with a more complete ecological safety plan.
At the same time, recent studies have pointed to a variety
of other problems that seem to be emerging from Bt corn.
One report, for example, suggests that the EPA's primary
strategy for preventing the emergence of Bt-resistant
insects -- a plan that calls for planting "refuges" of
conventional corn in nearby fields -- may be doomed to fail
because Bt resistance genes in insects behave differently
than scientists had thought.
Another study showed that Bt can alter the time it takes an
insect to reach adulthood. That could dash the EPA's hopes
that Bt-resistant insects will mate with Bt-susceptible
ones and give birth to offspring still vulnerable to the
chemical.
Still other studies suggest that Bt corn may be
inadvertently killing beneficial insects such as ladybugs
and lacewings, which eat insect pests. If true, then the
insecticidal crops may be giving reprieves to as many
insect pests as they are killing.
And scientists are finding that some engineered crops, such
as herbicide-resistant canola in Canada, are
cross-pollinating with wild relatives more widely than had
been predicted, creating hardy weeds that can survive
herbicidal sprays.
Now, the EPA faces a potentially larger problem: whether to
approve a new kind of Bt corn called Bt cry9C. It's a
decision that many observers see as a test case of just
where the agency will draw the line on the degree of risk
it is willing to accept.
While other versions of Bt break down harmlessly in the
human digestive tract, the cry9C protein remains stable in
the human stomach. And because the protein can survive
digestion, it has increased potential to cause allergies.
The FDA demands extra allergy testing for new food that
contains such stable proteins. And AgrEvo, the German
company that is seeking approval for cry9C corn, has
conducted some additional tests, including a comparison of
cry9C's molecular structure with known allergy-causing
proteins. Reassuringly no similarities exist.
But as the agency considers whether to approve the corn for
human ingestion, it is up against the reality that there is
no surefire way of testing a new protein like cry9C for its
potential to cause allergies in people.
"We all wish there was a test where you plug in a protein
and out pops a 'yes' or 'no' answer," said Sue MacIntosh, a
protein chemist with AgrEvo.
But there is no such test, short of giving it to a lot of
people and seeing what happens.
The EPA is considering the company's application and hopes
to make a decision by fall.
THE NEW BIOLOGY
Human cloning, once thought impossible, today seems
possible, and perhaps even probable. Growing spare body
parts in the lab, once the stuff of science fiction, is
being pursued by scientists everywhere. Embryos are being
genetically selected to be healthy, or male; "designer
babies" may not be too far behind. Plants genetically
engineered to produce their own pesticides, and even
certain types of plastics, are growing in fields. Science
is entering a new world where the once-unthinkable is
suddenly doable. The Washington Post is examining this
scientific revolution in a series of occasional articles
about this new biology exploding at the turn of the
century.
ON THE SHELF
Much of the corn, soy and cotton grown in the United States
is genetically engineered. Therefore, ingesting food made
from genetically engineered crops is almost inevitable.
Percentage of U.S. crop that's genetically engineered:
Corn 33%
Soy 50%
Cotton 50%
Products that may contain one or more genetically
engineered ingredient:
Corn
* Juice
* Soda
Cotton
* Nuts
Soy
* Tuna
Corn & Soy
* Frozen pizza
* Spaghetti sauce
* Crackers
* Cookies
* Salad dressing
Corn, Soy & Cotton
* Soup
© Copyright 1999 The Washington Post Company
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